Commit Graph

22141 Commits

Author SHA1 Message Date
Andy Lutomirski
cced0b24bb selftests/x86: Consolidate and fix get/set_eflags() helpers
There are several copies of get_eflags() and set_eflags() and they all are
buggy.  Consolidate them and fix them.  The fixes are:

Add memory clobbers.  These are probably unnecessary but they make sure
that the compiler doesn't move something past one of these calls when it
shouldn't.

Respect the redzone on x86_64.  There has no failure been observed related
to this, but it's definitely a bug.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/982ce58ae8dea2f1e57093ee894760e35267e751.1593191971.git.luto@kernel.org
2020-07-01 10:00:27 +02:00
Andy Lutomirski
a61fa2799e selftests/x86/syscall_nt: Clear weird flags after each test
Clear the weird flags before logging to improve strace output --
logging results while, say, TF is set does no one any favors.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/907bfa5a42d4475b8245e18b67a04b13ca51ffdb.1593191971.git.luto@kernel.org
2020-07-01 10:00:26 +02:00
Andy Lutomirski
e4ef7de160 selftests/x86/syscall_nt: Add more flag combinations
Add EFLAGS.AC to the mix.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/12924e2fe2c5826568b7fc9436d85ca7f5eb1743.1593191971.git.luto@kernel.org
2020-07-01 10:00:26 +02:00
Andrii Nakryiko
8c18311067 selftests/bpf: Add byte swapping selftest
Add simple selftest validating byte swap built-ins and compile-time macros.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20200630152125.3631920-3-andriin@fb.com
2020-07-01 09:06:12 +02:00
Andrii Nakryiko
30ad688094 libbpf: Make bpf_endian co-exist with vmlinux.h
Make bpf_endian.h compatible with vmlinux.h. It is a frequent request from
users wanting to use bpf_endian.h in their BPF applications using CO-RE and
vmlinux.h.

To achieve that, re-implement byte swap macros and drop all the header
includes. This way it can be used both with linux header includes, as well as
with a vmlinux.h.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20200630152125.3631920-2-andriin@fb.com
2020-07-01 09:06:12 +02:00
Andrii Nakryiko
ca4db6389d selftests/bpf: Allow substituting custom vmlinux.h for selftests build
Similarly to bpftool Makefile, allow to specify custom location of vmlinux.h
to be used during the build. This allows simpler testing setups with
checked-in pre-generated vmlinux.h.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20200630004759.521530-2-andriin@fb.com
2020-06-30 15:50:11 -07:00
Andrii Nakryiko
ec23eb7056 tools/bpftool: Allow substituting custom vmlinux.h for the build
In some build contexts (e.g., Travis CI build for outdated kernel), vmlinux.h,
generated from available kernel, doesn't contain all the types necessary for
BPF program compilation. For such set up, the most maintainable way to deal
with this problem is to keep pre-generated (almost up-to-date) vmlinux.h
checked in and use it for compilation purposes. bpftool after that can deal
with kernel missing some of the features in runtime with no problems.

To that effect, allow to specify path to custom vmlinux.h to bpftool's
Makefile with VMLINUX_H variable.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20200630004759.521530-1-andriin@fb.com
2020-06-30 15:50:11 -07:00
David S. Miller
e708e2bd55 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf
Daniel Borkmann says:

====================
pull-request: bpf 2020-06-30

The following pull-request contains BPF updates for your *net* tree.

We've added 28 non-merge commits during the last 9 day(s) which contain
a total of 35 files changed, 486 insertions(+), 232 deletions(-).

The main changes are:

1) Fix an incorrect verifier branch elimination for PTR_TO_BTF_ID pointer
   types, from Yonghong Song.

2) Fix UAPI for sockmap and flow_dissector progs that were ignoring various
   arguments passed to BPF_PROG_{ATTACH,DETACH}, from Lorenz Bauer & Jakub Sitnicki.

3) Fix broken AF_XDP DMA hacks that are poking into dma-direct and swiotlb
   internals and integrate it properly into DMA core, from Christoph Hellwig.

4) Fix RCU splat from recent changes to avoid skipping ingress policy when
   kTLS is enabled, from John Fastabend.

5) Fix BPF ringbuf map to enforce size to be the power of 2 in order for its
   position masking to work, from Andrii Nakryiko.

6) Fix regression from CAP_BPF work to re-allow CAP_SYS_ADMIN for loading
   of network programs, from Maciej Żenczykowski.

7) Fix libbpf section name prefix for devmap progs, from Jesper Dangaard Brouer.

8) Fix formatting in UAPI documentation for BPF helpers, from Quentin Monnet.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2020-06-30 14:20:45 -07:00
Yonghong Song
d923021c2c bpf: Add tests for PTR_TO_BTF_ID vs. null comparison
Add two tests for PTR_TO_BTF_ID vs. null ptr comparison,
one for PTR_TO_BTF_ID in the ctx structure and the
other for PTR_TO_BTF_ID after one level pointer chasing.
In both cases, the test ensures condition is not
removed.

For example, for this test
 struct bpf_fentry_test_t {
     struct bpf_fentry_test_t *a;
 };
 int BPF_PROG(test7, struct bpf_fentry_test_t *arg)
 {
     if (arg == 0)
         test7_result = 1;
     return 0;
 }
Before the previous verifier change, we have xlated codes:
  int test7(long long unsigned int * ctx):
  ; int BPF_PROG(test7, struct bpf_fentry_test_t *arg)
     0: (79) r1 = *(u64 *)(r1 +0)
  ; int BPF_PROG(test7, struct bpf_fentry_test_t *arg)
     1: (b4) w0 = 0
     2: (95) exit
After the previous verifier change, we have:
  int test7(long long unsigned int * ctx):
  ; int BPF_PROG(test7, struct bpf_fentry_test_t *arg)
     0: (79) r1 = *(u64 *)(r1 +0)
  ; if (arg == 0)
     1: (55) if r1 != 0x0 goto pc+4
  ; test7_result = 1;
     2: (18) r1 = map[id:6][0]+48
     4: (b7) r2 = 1
     5: (7b) *(u64 *)(r1 +0) = r2
  ; int BPF_PROG(test7, struct bpf_fentry_test_t *arg)
     6: (b4) w0 = 0
     7: (95) exit

Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200630171241.2523875-1-yhs@fb.com
2020-06-30 22:21:29 +02:00
Lorenz Bauer
1a1ad3c20a selftests: bpf: Pass program to bpf_prog_detach in flow_dissector
Calling bpf_prog_detach is incorrect, since it takes target_fd as
its argument. The intention here is to pass it as attach_bpf_fd,
so use bpf_prog_detach2 and pass zero for target_fd.

Fixes: 06716e04a0 ("selftests/bpf: Extend test_flow_dissector to cover link creation")
Signed-off-by: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200629095630.7933-7-lmb@cloudflare.com
2020-06-30 10:46:39 -07:00
Lorenz Bauer
0434296c72 selftests: bpf: Pass program and target_fd in flow_dissector_reattach
Pass 0 as target_fd when attaching and detaching flow dissector.
Additionally, pass the expected program when detaching.

Fixes: 1f043f87bb ("selftests/bpf: Add tests for attaching bpf_link to netns")
Signed-off-by: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200629095630.7933-6-lmb@cloudflare.com
2020-06-30 10:46:39 -07:00
Jakub Sitnicki
6ebb85c83a selftests/bpf: Test updating flow_dissector link with same program
This case, while not particularly useful, is worth covering because we
expect the operation to succeed as opposed when re-attaching the same
program directly with PROG_ATTACH.

While at it, update the tests summary that fell out of sync when tests
extended to cover links.

Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20200625141357.910330-5-jakub@cloudflare.com
2020-06-30 10:45:08 -07:00
Amit Cohen
7d10bcce98 selftests: forwarding: Add tests for ethtool extended state
Add tests to check ethtool report about extended state.
The tests configure several states and verify that the correct extended
state is reported by ethtool.

Check extended state with substate (Autoneg) and extended state without
substate (No cable).

Signed-off-by: Amit Cohen <amitc@mellanox.com>
Reviewed-by: Petr Machata <petrm@mellanox.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-06-29 17:45:02 -07:00
Amit Cohen
0433045c27 selftests: forwarding: forwarding.config.sample: Add port with no cable connected
Add NETIF_NO_CABLE port to tests topology.

The port can also be declared as an environment variable and tests can be
run like that:
NETIF_NO_CABLE=eth9 ./test.sh eth{1..8}

The NETIF_NO_CABLE port will be used by ethtool_extended_state test.

Signed-off-by: Amit Cohen <amitc@mellanox.com>
Reviewed-by: Petr Machata <petrm@mellanox.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-06-29 17:45:02 -07:00
Amit Cohen
dd9e67ff80 selftests: forwarding: ethtool: Move different_speeds_get() to ethtool_lib
Currently different_speeds_get() is used only by ethtool.sh tests.
The function can be useful for another tests that check ethtool
configurations.

Move the function to ethtool_lib in order to allow other tests to use
it.

Signed-off-by: Amit Cohen <amitc@mellanox.com>
Reviewed-by: Petr Machata <petrm@mellanox.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-06-29 17:45:02 -07:00
Petr Machata
6cf0291f95 selftests: forwarding: Add a RED test for SW datapath
This test is inspired by the mlxsw RED selftest. It is much simpler to set
up (also because there is no point in testing PRIO / RED encapsulation). It
tests bare RED, ECN and ECN+nodrop modes of operation. On top of that it
tests RED early_drop and mark qevents.

Signed-off-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-06-29 17:08:28 -07:00
Jarkko Sakkinen
377ff83083 selftests: tpm: Use /bin/sh instead of /bin/bash
It's better to use /bin/sh instead of /bin/bash in order to run the tests
in the BusyBox shell.

Fixes: 6ea3dfe1e0 ("selftests: add TPM 2.0 tests")
Cc: stable@vger.kernel.org
Cc: linux-integrity@vger.kernel.org
Cc: linux-kselftest@vger.kernel.org
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2020-06-29 14:19:38 -06:00
Jarkko Sakkinen
88a16840f4 selftests: tpm: Use 'test -e' instead of 'test -f'
'test -f' is suitable only for *regular* files. Use 'test -e' instead.

Cc: Nikita Sobolev <Nikita.Sobolev@synopsys.com>
Cc: linux-integrity@vger.kernel.org
Cc: linux-kselftest@vger.kernel.org
Fixes: 5627f9cffe ("Kernel selftests: Add check if TPM devices are supported")
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2020-06-29 14:19:23 -06:00
Jarkko Sakkinen
5be206eaac Revert "tpm: selftest: cleanup after unseal with wrong auth/policy test"
The reverted commit illegitly uses tpm2-tools. External dependencies are
absolutely forbidden from these tests. There is also the problem that
clearing is not necessarily wanted behavior if the test/target computer is
not used only solely for testing.

Fixes: a9920d3bad ("tpm: selftest: cleanup after unseal with wrong auth/policy test")
Cc: Tadeusz Struk <tadeusz.struk@intel.com>
Cc: stable@vger.kernel.org
Cc: linux-integrity@vger.kernel.org
Cc: linux-kselftest@vger.kernel.org
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2020-06-29 14:18:15 -06:00
Linus Torvalds
7ecb59a566 Peter Zijlstra says:
Address KCOV vs noinstr. There is no function attribute to selectively
 suppress KCOV instrumentation, instead teach objtool to NOP out the
 calls in noinstr functions.
 
 This cures a bunch of KCOV crashes (as used by syzcaller).
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Merge tag 'objtool_urgent_for_5.8_rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull objtool fixes from Borislav Petkov:
 "Three fixes from Peter Zijlstra suppressing KCOV instrumentation in
  noinstr sections.

  Peter Zijlstra says:
    "Address KCOV vs noinstr. There is no function attribute to
     selectively suppress KCOV instrumentation, instead teach objtool
     to NOP out the calls in noinstr functions"

  This cures a bunch of KCOV crashes (as used by syzcaller)"

* tag 'objtool_urgent_for_5.8_rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  objtool: Fix noinstr vs KCOV
  objtool: Provide elf_write_{insn,reloc}()
  objtool: Clean up elf_write() condition
2020-06-28 10:16:15 -07:00
Andrii Nakryiko
5712174c5c selftests/bpf: Test auto-load disabling logic for BPF programs
Validate that BPF object with broken (in multiple ways) BPF program can still
be successfully loaded, if that broken BPF program is disabled.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200625232629.3444003-3-andriin@fb.com
2020-06-28 10:06:53 -07:00
Andrii Nakryiko
d929758101 libbpf: Support disabling auto-loading BPF programs
Currently, bpf_object__load() (and by induction skeleton's load), will always
attempt to prepare, relocate, and load into kernel every single BPF program
found inside the BPF object file. This is often convenient and the right thing
to do and what users expect.

But there are plenty of cases (especially with BPF development constantly
picking up the pace), where BPF application is intended to work with old
kernels, with potentially reduced set of features. But on kernels supporting
extra features, it would like to take a full advantage of them, by employing
extra BPF program. This could be a choice of using fentry/fexit over
kprobe/kretprobe, if kernel is recent enough and is built with BTF. Or BPF
program might be providing optimized bpf_iter-based solution that user-space
might want to use, whenever available. And so on.

With libbpf and BPF CO-RE in particular, it's advantageous to not have to
maintain two separate BPF object files to achieve this. So to enable such use
cases, this patch adds ability to request not auto-loading chosen BPF
programs. In such case, libbpf won't attempt to perform relocations (which
might fail due to old kernel), won't try to resolve BTF types for
BTF-aware (tp_btf/fentry/fexit/etc) program types, because BTF might not be
present, and so on. Skeleton will also automatically skip auto-attachment step
for such not loaded BPF programs.

Overall, this feature allows to simplify development and deployment of
real-world BPF applications with complicated compatibility requirements.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200625232629.3444003-2-andriin@fb.com
2020-06-28 10:06:53 -07:00
Linus Torvalds
a358505d8a Peter Zijlstra says:
These patches address a number of instrumentation issues that were found after
 the x86/entry overhaul. When combined with rcu/urgent and objtool/urgent, these
 patches make UBSAN/KASAN/KCSAN happy again.
 
 Part of making this all work is bumping the minimum GCC version for KASAN
 builds to gcc-8.3, the reason for this is that the __no_sanitize_address
 function attribute is broken in GCC releases before that.
 
 No known GCC version has a working __no_sanitize_undefined, however because the
 only noinstr violation that results from this happens when an UB is found, we
 treat it like WARN. That is, we allow it to violate the noinstr rules in order
 to get the warning out.
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Merge tag 'x86_entry_for_5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 entry fixes from Borislav Petkov:
 "This is the x86/entry urgent pile which has accumulated since the
  merge window.

  It is not the smallest but considering the almost complete entry core
  rewrite, the amount of fixes to follow is somewhat higher than usual,
  which is to be expected.

  Peter Zijlstra says:
   'These patches address a number of instrumentation issues that were
    found after the x86/entry overhaul. When combined with rcu/urgent
    and objtool/urgent, these patches make UBSAN/KASAN/KCSAN happy
    again.

    Part of making this all work is bumping the minimum GCC version for
    KASAN builds to gcc-8.3, the reason for this is that the
    __no_sanitize_address function attribute is broken in GCC releases
    before that.

    No known GCC version has a working __no_sanitize_undefined, however
    because the only noinstr violation that results from this happens
    when an UB is found, we treat it like WARN. That is, we allow it to
    violate the noinstr rules in order to get the warning out'"

* tag 'x86_entry_for_5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/entry: Fix #UD vs WARN more
  x86/entry: Increase entry_stack size to a full page
  x86/entry: Fixup bad_iret vs noinstr
  objtool: Don't consider vmlinux a C-file
  kasan: Fix required compiler version
  compiler_attributes.h: Support no_sanitize_undefined check with GCC 4
  x86/entry, bug: Comment the instrumentation_begin() usage for WARN()
  x86/entry, ubsan, objtool: Whitelist __ubsan_handle_*()
  x86/entry, cpumask: Provide non-instrumented variant of cpu_is_offline()
  compiler_types.h: Add __no_sanitize_{address,undefined} to noinstr
  kasan: Bump required compiler version
  x86, kcsan: Add __no_kcsan to noinstr
  kcsan: Remove __no_kcsan_or_inline
  x86, kcsan: Remove __no_kcsan_or_inline usage
2020-06-28 09:42:47 -07:00
John Fastabend
53792fa45b bpf, sockmap: Add ingres skb tests that utilize merge skbs
Add a test to check strparser merging skbs is working.

Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/159312681884.18340.4922800172600252370.stgit@john-XPS-13-9370
2020-06-28 08:33:28 -07:00
Linus Torvalds
21d2f6850c powerpc fixes for 5.8 #4
A fix for a crash in nested KVM when CONFIG_DEBUG_VIRTUAL=y.
 
 Two minor build fixes.
 
 Thanks to:
   Aneesh Kumar K.V, Arseny Solokha, Harish.
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Merge tag 'powerpc-5.8-4' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc fixes from Michael Ellerman:

 - A fix for a crash in nested KVM when CONFIG_DEBUG_VIRTUAL=y.

 - Two minor build fixes.

Thanks to: Aneesh Kumar K.V, Arseny Solokha, Harish.

* tag 'powerpc-5.8-4' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  selftests/powerpc: Fix build failure in ebb tests
  powerpc/kvm/book3s64: Fix kernel crash with nested kvm & DEBUG_VIRTUAL
  powerpc/fsl_booke/32: Fix build with CONFIG_RANDOMIZE_BASE
2020-06-27 08:51:35 -07:00
Linus Torvalds
8530684fd3 arm64 fixes for -rc3
- Fix unwinding through vDSO sigreturn trampoline
 
 - Fix build warnings by raising minimum LD version for PAC
 
 - Whitelist some Kryo Cortex-A55 derivatives for Meltdown and SSB
 
 - Fix perf register PC reporting for compat tasks
 
 - Fix 'make clean' warning for arm64 signal selftests
 
 - Fix ftrace when BTI is compiled in
 
 - Avoid building the compat vDSO using GCC plugins
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Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

Pull arm64 fixes from Will Deacon:
 "The big fix here is to our vDSO sigreturn trampoline as, after a
  painfully long stint of debugging, it turned out that fixing some of
  our CFI directives in the merge window lit up a bunch of logic in
  libgcc which has been shown to SEGV in some cases during asynchronous
  pthread cancellation.

  It looks like we can fix this by extending the directives to restore
  most of the interrupted register state from the sigcontext, but it's
  risky and hard to test so we opted to remove the CFI directives for
  now and rely on the unwinder fallback path like we used to.

   - Fix unwinding through vDSO sigreturn trampoline

   - Fix build warnings by raising minimum LD version for PAC

   - Whitelist some Kryo Cortex-A55 derivatives for Meltdown and SSB

   - Fix perf register PC reporting for compat tasks

   - Fix 'make clean' warning for arm64 signal selftests

   - Fix ftrace when BTI is compiled in

   - Avoid building the compat vDSO using GCC plugins"

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  arm64: Add KRYO{3,4}XX silver CPU cores to SSB safelist
  arm64: perf: Report the PC value in REGS_ABI_32 mode
  kselftest: arm64: Remove redundant clean target
  arm64: kpti: Add KRYO{3, 4}XX silver CPU cores to kpti safelist
  arm64: Don't insert a BTI instruction at inner labels
  arm64: vdso: Don't use gcc plugins for building vgettimeofday.c
  arm64: vdso: Only pass --no-eh-frame-hdr when linker supports it
  arm64: Depend on newer binutils when building PAC
  arm64: compat: Remove 32-bit sigreturn code from the vDSO
  arm64: compat: Always use sigpage for sigreturn trampoline
  arm64: compat: Allow 32-bit vdso and sigpage to co-exist
  arm64: vdso: Disable dwarf unwinding through the sigreturn trampoline
2020-06-27 08:47:18 -07:00
David Gow
ee61492ab9 kunit: kunit_tool: Fix invalid result when build fails
When separating out different phases of running tests[1]
(build/exec/parse/etc), the format of the KunitResult tuple changed
(adding an elapsed_time variable). This is not populated during a build
failure, causing kunit.py to crash.

This fixes [1] to probably populate the result variable, causing a
failing build to be reported properly.

[1]:
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=45ba7a893ad89114e773b3dc32f6431354c465d6

Signed-off-by: David Gow <davidgow@google.com>
Reviewed-by: Brendan Higgins <brendanhiggins@google.com>
Tested-by: Brendan Higgins <brendanhiggins@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2020-06-26 14:29:31 -06:00
Uriel Guajardo
e173b8b8c4 kunit: show error if kunit results are not present
Currently, if the kernel is configured incorrectly or if it crashes before any
kunit tests are run, kunit finishes without error, reporting
that 0 test cases were run.

To fix this, an error is shown when the tap header is not found, which
indicates that kunit was not able to run at all.

Signed-off-by: Uriel Guajardo <urielguajardo@google.com>
Reviewed-by: Brendan Higgins <brendanhiggins@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2020-06-26 14:29:10 -06:00
Rikard Falkeborn
3f37d14b8a kunit: kunit_config: Fix parsing of CONFIG options with space
Commit 8b59cd81dc ("kbuild: ensure full rebuild when the compiler is
updated") introduced a new CONFIG option CONFIG_CC_VERSION_TEXT. On my
system, this is set to "gcc (GCC) 10.1.0" which breaks KUnit config
parsing which did not like the spaces in the string.

Fix this by updating the regex to allow strings containing spaces.

Fixes: 8b59cd81dc ("kbuild: ensure full rebuild when the compiler is updated")
Signed-off-by: Rikard Falkeborn <rikard.falkeborn@gmail.com>
Reviewed-by: Brendan Higgins <brendanhiggins@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2020-06-26 14:27:35 -06:00
Ingo Molnar
2c92d787cc Merge branch 'linus' into x86/entry, to resolve conflicts
Conflicts:
	arch/x86/kernel/traps.c

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-06-26 12:24:42 +02:00
Harish
896066aa06 selftests/powerpc: Fix build failure in ebb tests
We use OUTPUT directory as TMPOUT for checking no-pie option.

Since commit f2f02ebd8f ("kbuild: improve cc-option to clean up all
temporary files") when building powerpc/ from selftests directory, the
OUTPUT directory points to powerpc/pmu/ebb/ and gets removed when
checking for -no-pie option in try-run routine, subsequently build
fails with the following:

  $ make -C powerpc
  ...
  TARGET=ebb; BUILD_TARGET=$OUTPUT/$TARGET; mkdir -p $BUILD_TARGET; make OUTPUT=$BUILD_TARGET -k -C $TARGET all
  make[2]: Entering directory '/home/linux-master/tools/testing/selftests/powerpc/pmu/ebb'
  make[2]: *** No rule to make target 'Makefile'.
  make[2]: Failed to remake makefile 'Makefile'.
  make[2]: *** No rule to make target 'ebb.c', needed by '/home/linux-master/tools/testing/selftests/powerpc/pmu/ebb/reg_access_test'.
  make[2]: *** No rule to make target 'ebb_handler.S', needed by '/home/linux-master/tools/testing/selftests/powerpc/pmu/ebb/reg_access_test'.
  make[2]: *** No rule to make target 'trace.c', needed by '/home/linux-master/tools/testing/selftests/powerpc/pmu/ebb/reg_access_test'.
  make[2]: *** No rule to make target 'busy_loop.S', needed by '/home/linux-master/tools/testing/selftests/powerpc/pmu/ebb/reg_access_test'.
  make[2]: Target 'all' not remade because of errors.

Fix this by adding a suffix to the OUTPUT directory so that the
failure is avoided.

Fixes: 9686813f6e ("selftests/powerpc: Fix try-run when source tree is not writable")
Signed-off-by: Harish <harish@linux.ibm.com>
[mpe: Mention that commit that triggered the breakage]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200625165721.264904-1-harish@linux.ibm.com
2020-06-26 12:53:09 +10:00
David S. Miller
7bed145516 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Minor overlapping changes in xfrm_device.c, between the double
ESP trailing bug fix setting the XFRM_INIT flag and the changes
in net-next preparing for bonding encryption support.

Signed-off-by: David S. Miller <davem@davemloft.net>
2020-06-25 19:29:51 -07:00
Linus Torvalds
4a21185cda Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Pull networking fixes from David Miller:

 1) Don't insert ESP trailer twice in IPSEC code, from Huy Nguyen.

 2) The default crypto algorithm selection in Kconfig for IPSEC is out
    of touch with modern reality, fix this up. From Eric Biggers.

 3) bpftool is missing an entry for BPF_MAP_TYPE_RINGBUF, from Andrii
    Nakryiko.

 4) Missing init of ->frame_sz in xdp_convert_zc_to_xdp_frame(), from
    Hangbin Liu.

 5) Adjust packet alignment handling in ax88179_178a driver to match
    what the hardware actually does. From Jeremy Kerr.

 6) register_netdevice can leak in the case one of the notifiers fail,
    from Yang Yingliang.

 7) Use after free in ip_tunnel_lookup(), from Taehee Yoo.

 8) VLAN checks in sja1105 DSA driver need adjustments, from Vladimir
    Oltean.

 9) tg3 driver can sleep forever when we get enough EEH errors, fix from
    David Christensen.

10) Missing {READ,WRITE}_ONCE() annotations in various Intel ethernet
    drivers, from Ciara Loftus.

11) Fix scanning loop break condition in of_mdiobus_register(), from
    Florian Fainelli.

12) MTU limit is incorrect in ibmveth driver, from Thomas Falcon.

13) Endianness fix in mlxsw, from Ido Schimmel.

14) Use after free in smsc95xx usbnet driver, from Tuomas Tynkkynen.

15) Missing bridge mrp configuration validation, from Horatiu Vultur.

16) Fix circular netns references in wireguard, from Jason A. Donenfeld.

17) PTP initialization on recovery is not done properly in qed driver,
    from Alexander Lobakin.

18) Endian conversion of L4 ports in filters of cxgb4 driver is wrong,
    from Rahul Lakkireddy.

19) Don't clear bound device TX queue of socket prematurely otherwise we
    get problems with ktls hw offloading, from Tariq Toukan.

20) ipset can do atomics on unaligned memory, fix from Russell King.

21) Align ethernet addresses properly in bridging code, from Thomas
    Martitz.

22) Don't advertise ipv4 addresses on SCTP sockets having ipv6only set,
    from Marcelo Ricardo Leitner.

* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (149 commits)
  rds: transport module should be auto loaded when transport is set
  sch_cake: fix a few style nits
  sch_cake: don't call diffserv parsing code when it is not needed
  sch_cake: don't try to reallocate or unshare skb unconditionally
  ethtool: fix error handling in linkstate_prepare_data()
  wil6210: account for napi_gro_receive never returning GRO_DROP
  hns: do not cast return value of napi_gro_receive to null
  socionext: account for napi_gro_receive never returning GRO_DROP
  wireguard: receive: account for napi_gro_receive never returning GRO_DROP
  vxlan: fix last fdb index during dump of fdb with nhid
  sctp: Don't advertise IPv4 addresses if ipv6only is set on the socket
  tc-testing: avoid action cookies with odd length.
  bpf: tcp: bpf_cubic: fix spurious HYSTART_DELAY exit upon drop in min RTT
  tcp_cubic: fix spurious HYSTART_DELAY exit upon drop in min RTT
  net: dsa: sja1105: fix tc-gate schedule with single element
  net: dsa: sja1105: recalculate gating subschedule after deleting tc-gate rules
  net: dsa: sja1105: unconditionally free old gating config
  net: dsa: sja1105: move sja1105_compose_gating_subschedule at the top
  net: macb: free resources on failure path of at91ether_open()
  net: macb: call pm_runtime_put_sync on failure path
  ...
2020-06-25 18:27:40 -07:00
Briana Oursler
b6186d413b tc-testing: avoid action cookies with odd length.
Update odd length cookie hexstrings in csum.json, tunnel_key.json and
bpf.json to be even length to comply with check enforced in commit
0149dabf2a1b ("tc: m_actions: check cookie hexstring len") in iproute2.

Signed-off-by: Briana Oursler <briana.oursler@gmail.com>
Reviewed-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: Davide Caratti <dcaratti@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-06-25 16:10:45 -07:00
Neal Cardwell
7d21d54d62 bpf: tcp: bpf_cubic: fix spurious HYSTART_DELAY exit upon drop in min RTT
Apply the fix from:
 "tcp_cubic: fix spurious HYSTART_DELAY exit upon drop in min RTT"
to the BPF implementation of TCP CUBIC congestion control.

Repeating the commit description here for completeness:

Mirja Kuehlewind reported a bug in Linux TCP CUBIC Hystart, where
Hystart HYSTART_DELAY mechanism can exit Slow Start spuriously on an
ACK when the minimum rtt of a connection goes down. From inspection it
is clear from the existing code that this could happen in an example
like the following:

o The first 8 RTT samples in a round trip are 150ms, resulting in a
  curr_rtt of 150ms and a delay_min of 150ms.

o The 9th RTT sample is 100ms. The curr_rtt does not change after the
  first 8 samples, so curr_rtt remains 150ms. But delay_min can be
  lowered at any time, so delay_min falls to 100ms. The code executes
  the HYSTART_DELAY comparison between curr_rtt of 150ms and delay_min
  of 100ms, and the curr_rtt is declared far enough above delay_min to
  force a (spurious) exit of Slow start.

The fix here is simple: allow every RTT sample in a round trip to
lower the curr_rtt.

Fixes: 6de4a9c430 ("bpf: tcp: Add bpf_cubic example")
Reported-by: Mirja Kuehlewind <mirja.kuehlewind@ericsson.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-06-25 16:08:47 -07:00
Jesper Dangaard Brouer
7a64135f32 libbpf: Adjust SEC short cut for expected attach type BPF_XDP_DEVMAP
Adjust the SEC("xdp_devmap/") prog type prefix to contain a
slash "/" for expected attach type BPF_XDP_DEVMAP.  This is consistent
with other prog types like tracing.

Fixes: 2778797037 ("libbpf: Add SEC name for xdp programs attached to device map")
Suggested-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/159309521882.821855.6873145686353617509.stgit@firesoul
2020-06-25 22:36:00 +02:00
David S. Miller
f4926d513b Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf
Pablo Neira Ayuso says:

====================
Netfilter fixes for net

The following patchset contains Netfilter fixes for net, they are:

1) Unaligned atomic access in ipset, from Russell King.

2) Missing module description, from Rob Gill.

3) Patches to fix a module unload causing NULL pointer dereference in
   xtables, from David Wilder. For the record, I posting here his cover
   letter explaining the problem:

    A crash happened on ppc64le when running ltp network tests triggered by
    "rmmod iptable_mangle".

    See previous discussion in this thread:
    https://lists.openwall.net/netdev/2020/06/03/161 .

    In the crash I found in iptable_mangle_hook() that
    state->net->ipv4.iptable_mangle=NULL causing a NULL pointer dereference.
    net->ipv4.iptable_mangle is set to NULL in +iptable_mangle_net_exit() and
    called when ip_mangle modules is unloaded. A rmmod task was found running
    in the crash dump.  A 2nd crash showed the same problem when running
    "rmmod iptable_filter" (net->ipv4.iptable_filter=NULL).

    To fix this I added .pre_exit hook in all iptable_foo.c. The pre_exit will
    un-register the underlying hook and exit would do the table freeing. The
    netns core does an unconditional +synchronize_rcu after the pre_exit hooks
    insuring no packets are in flight that have picked up the pointer before
    completing the un-register.

    These patches include changes for both iptables and ip6tables.

    We tested this fix with ltp running iptables01.sh and iptables01.sh -6 a
    loop for 72 hours.

4) Add a selftest for conntrack helper assignment, from Florian Westphal.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2020-06-25 12:52:41 -07:00
Tobias Klauser
16d37ee3d2 tools, bpftool: Define attach_type_name array only once
Define attach_type_name in common.c instead of main.h so it is only
defined once. This leads to a slight decrease in the binary size of
bpftool.

Before:

   text	   data	    bss	    dec	    hex	filename
 399024	  11168	1573160	1983352	 1e4378	bpftool

After:

   text	   data	    bss	    dec	    hex	filename
 398256	  10880	1573160	1982296	 1e3f58	bpftool

Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/20200624143154.13145-1-tklauser@distanz.ch
2020-06-25 16:06:01 +02:00
Tobias Klauser
9023497d87 tools, bpftool: Define prog_type_name array only once
Define prog_type_name in prog.c instead of main.h so it is only defined
once. This leads to a slight decrease in the binary size of bpftool.

Before:

   text	   data	    bss	    dec	    hex	filename
 401032	  11936	1573160	1986128	 1e4e50	bpftool

After:

   text	   data	    bss	    dec	    hex	filename
 399024	  11168	1573160	1983352	 1e4378	bpftool

Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/20200624143124.12914-1-tklauser@distanz.ch
2020-06-25 16:06:01 +02:00
Peter Zijlstra
734d099ba6 objtool: Don't consider vmlinux a C-file
Avoids issuing C-file warnings for vmlinux.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200618144801.701257527@infradead.org
2020-06-25 13:45:39 +02:00
Yonghong Song
cfcd75f9bf selftests/bpf: Add tcp/udp iterator programs to selftests
Added tcp{4,6} and udp{4,6} bpf programs into test_progs
selftest so that they at least can load successfully.
  $ ./test_progs -n 3
  ...
  #3/7 tcp4:OK
  #3/8 tcp6:OK
  #3/9 udp4:OK
  #3/10 udp6:OK
  ...
  #3 bpf_iter:OK
  Summary: 1/16 PASSED, 0 SKIPPED, 0 FAILED

Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20200623230823.3989372-1-yhs@fb.com
2020-06-24 18:38:00 -07:00
Yonghong Song
ace6d6ec9e selftests/bpf: Implement sample udp/udp6 bpf_iter programs
On my VM, I got identical results between /proc/net/udp[6] and
the udp{4,6} bpf iterator.

For udp6:
  $ cat /sys/fs/bpf/p1
    sl  local_address                         remote_address                        st tx_queue rx_queue tr tm->when retrnsmt   uid  timeout inode ref pointer drops
   1405: 000080FE00000000FF7CC4D0D9EFE4FE:0222 00000000000000000000000000000000:0000 07 00000000:00000000 00:00000000 00000000   193        0 19183 2 0000000029eab111 0
  $ cat /proc/net/udp6
    sl  local_address                         remote_address                        st tx_queue rx_queue tr tm->when retrnsmt   uid  timeout inode ref pointer drops
   1405: 000080FE00000000FF7CC4D0D9EFE4FE:0222 00000000000000000000000000000000:0000 07 00000000:00000000 00:00000000 00000000   193        0 19183 2 0000000029eab111 0

For udp4:
  $ cat /sys/fs/bpf/p4
    sl  local_address rem_address   st tx_queue rx_queue tr tm->when retrnsmt   uid  timeout inode ref pointer drops
   2007: 00000000:1F90 00000000:0000 07 00000000:00000000 00:00000000 00000000     0        0 72540 2 000000004ede477a 0
  $ cat /proc/net/udp
    sl  local_address rem_address   st tx_queue rx_queue tr tm->when retrnsmt   uid  timeout inode ref pointer drops
   2007: 00000000:1F90 00000000:0000 07 00000000:00000000 00:00000000 00000000     0        0 72540 2 000000004ede477a 0

Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20200623230822.3989299-1-yhs@fb.com
2020-06-24 18:37:59 -07:00
Yonghong Song
2767c97765 selftests/bpf: Implement sample tcp/tcp6 bpf_iter programs
In my VM, I got identical result compared to /proc/net/{tcp,tcp6}.
For tcp6:
  $ cat /proc/net/tcp6
    sl  local_address                         remote_address                        st tx_queue rx_queue tr tm->when retrnsmt   uid  timeout inode
     0: 00000000000000000000000000000000:0016 00000000000000000000000000000000:0000 0A 00000000:00000000 00:00000001 00000000     0        0 17955 1 000000003eb3102e 100 0 0 10 0

  $ cat /sys/fs/bpf/p1
    sl  local_address                         remote_address                        st tx_queue rx_queue tr tm->when retrnsmt   uid  timeout inode
     0: 00000000000000000000000000000000:0016 00000000000000000000000000000000:0000 0A 00000000:00000000 00:00000000 00000000     0        0 17955 1 000000003eb3102e 100 0 0 10 0

For tcp:
  $ cat /proc/net/tcp
  sl  local_address rem_address   st tx_queue rx_queue tr tm->when retrnsmt   uid  timeout inode
   0: 00000000:0016 00000000:0000 0A 00000000:00000000 00:00000000 00000000     0        0 2666 1 000000007152e43f 100 0 0 10 0
  $ cat /sys/fs/bpf/p2
  sl  local_address                         remote_address                        st tx_queue rx_queue tr tm->when retrnsmt   uid  timeout inode
   1: 00000000:0016 00000000:0000 0A 00000000:00000000 00:00000000 00000000     0        0 2666 1 000000007152e43f 100 0 0 10 0

Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20200623230820.3989165-1-yhs@fb.com
2020-06-24 18:37:59 -07:00
Yonghong Song
3982bfaaef selftests/bpf: Add more common macros to bpf_tracing_net.h
These newly added macros will be used in subsequent bpf iterator
tcp{4,6} and udp{4,6} programs.

Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20200623230819.3989050-1-yhs@fb.com
2020-06-24 18:37:59 -07:00
Yonghong Song
647b502e3d selftests/bpf: Refactor some net macros to bpf_tracing_net.h
Refactor bpf_iter_ipv6_route.c and bpf_iter_netlink.c
so net macros, originally from various include/linux header
files, are moved to a new header file
bpf_tracing_net.h. The goal is to improve reuse so
networking tracing programs do not need to
copy these macros every time they use them.

Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20200623230817.3988962-1-yhs@fb.com
2020-06-24 18:37:59 -07:00
Yonghong Song
84544f5637 selftests/bpf: Move newer bpf_iter_* type redefining to a new header file
Commit b9f4c01f3e ("selftest/bpf: Make bpf_iter selftest
compilable against old vmlinux.h") and Commit dda18a5c0b
("selftests/bpf: Convert bpf_iter_test_kern{3, 4}.c to define
own bpf_iter_meta") redefined newly introduced types
in bpf programs so the bpf program can still compile
properly with old kernels although loading may fail.

Since this patch set introduced new types and the same
workaround is needed, so let us move the workaround
to a separate header file so they do not clutter
bpf programs.

Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20200623230816.3988656-1-yhs@fb.com
2020-06-24 18:37:59 -07:00
Yonghong Song
0d4fad3e57 bpf: Add bpf_skc_to_udp6_sock() helper
The helper is used in tracing programs to cast a socket
pointer to a udp6_sock pointer.
The return value could be NULL if the casting is illegal.

Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Cc: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/bpf/20200623230815.3988481-1-yhs@fb.com
2020-06-24 18:37:59 -07:00
Yonghong Song
478cfbdf5f bpf: Add bpf_skc_to_{tcp, tcp_timewait, tcp_request}_sock() helpers
Three more helpers are added to cast a sock_common pointer to
an tcp_sock, tcp_timewait_sock or a tcp_request_sock for
tracing programs.

Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20200623230811.3988277-1-yhs@fb.com
2020-06-24 18:37:59 -07:00
Yonghong Song
af7ec13833 bpf: Add bpf_skc_to_tcp6_sock() helper
The helper is used in tracing programs to cast a socket
pointer to a tcp6_sock pointer.
The return value could be NULL if the casting is illegal.

A new helper return type RET_PTR_TO_BTF_ID_OR_NULL is added
so the verifier is able to deduce proper return types for the helper.

Different from the previous BTF_ID based helpers,
the bpf_skc_to_tcp6_sock() argument can be several possible
btf_ids. More specifically, all possible socket data structures
with sock_common appearing in the first in the memory layout.
This patch only added socket types related to tcp and udp.

All possible argument btf_id and return value btf_id
for helper bpf_skc_to_tcp6_sock() are pre-calculcated and
cached. In the future, it is even possible to precompute
these btf_id's at kernel build time.

Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20200623230809.3988195-1-yhs@fb.com
2020-06-24 18:37:59 -07:00
Florian Westphal
619ae8e069 selftests: netfilter: add test case for conntrack helper assignment
check that 'nft ... ct helper set <foo>' works:
 1. configure ftp helper via nft and assign it to
    connections on port 2121
 2. check with 'conntrack -L' that the next connection
    has the ftp helper attached to it.

Also add a test for auto-assign (old behaviour).

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2020-06-25 00:50:31 +02:00
Linus Torvalds
fc10807db5 virtio: fixes, tests
Fixes all over the place.
 
 This includes a couple of tests that I would normally defer,
 but since they have already been helpful in catching some bugs,
 don't build for any users at all, and having them
 upstream makes life easier for everyone, I think it's
 ok even at this late stage.
 
 Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost

Pull virtio fixes from Michael Tsirkin:
 "Fixes all over the place.

  This includes a couple of tests that I would normally defer, but since
  they have already been helpful in catching some bugs, don't build for
  any users at all, and having them upstream makes life easier for
  everyone, I think it's ok even at this late stage"

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
  tools/virtio: Use tools/include/list.h instead of stubs
  tools/virtio: Reset index in virtio_test --reset.
  tools/virtio: Extract virtqueue initialization in vq_reset
  tools/virtio: Use __vring_new_virtqueue in virtio_test.c
  tools/virtio: Add --reset
  tools/virtio: Add --batch=random option
  tools/virtio: Add --batch option
  virtio-mem: add memory via add_memory_driver_managed()
  virtio-mem: silence a static checker warning
  vhost_vdpa: Fix potential underflow in vhost_vdpa_mmap()
  vdpa: fix typos in the comments for __vdpa_alloc_device()
2020-06-24 14:26:28 -07:00
Linus Torvalds
fbb58011fd for-linus-2020-06-24
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Merge tag 'for-linus-2020-06-24' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux

Pull thread fix from Christian Brauner:
 "This fixes a regression introduced with 303cc571d1 ("nsproxy: attach
  to namespaces via pidfds").

  The LTP testsuite reported a regression where users would now see
  EBADF returned instead of EINVAL when an fd was passed that referred
  to an open file but the file was not a namespace file.

  Fix this by continuing to report EINVAL and add a regression test"

* tag 'for-linus-2020-06-24' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux:
  tests: test for setns() EINVAL regression
  nsproxy: restore EINVAL for non-namespace file descriptor
2020-06-24 14:19:45 -07:00
Dmitry Yakunin
f9bcf96837 bpf: Add SO_KEEPALIVE and related options to bpf_setsockopt
This patch adds support of SO_KEEPALIVE flag and TCP related options
to bpf_setsockopt() routine. This is helpful if we want to enable or tune
TCP keepalive for applications which don't do it in the userspace code.

v3:
  - update kernel-doc in uapi (Nikita Vetoshkin <nekto0n@yandex-team.ru>)

v4:
  - update kernel-doc in tools too (Alexei Starovoitov)
  - add test to selftests (Alexei Starovoitov)

Signed-off-by: Dmitry Yakunin <zeil@yandex-team.ru>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20200620153052.9439-3-zeil@yandex-team.ru
2020-06-24 11:21:03 -07:00
Alexei Starovoitov
fea549b030 selftests/bpf: Workaround for get_stack_rawtp test.
./test_progs-no_alu32 -t get_stack_raw_tp
fails due to:

52: (85) call bpf_get_stack#67
53: (bf) r8 = r0
54: (bf) r1 = r8
55: (67) r1 <<= 32
56: (c7) r1 s>>= 32
; if (usize < 0)
57: (c5) if r1 s< 0x0 goto pc+26
 R0=inv(id=0,smax_value=800) R1_w=inv(id=0,umax_value=800,var_off=(0x0; 0x3ff)) R6=ctx(id=0,off=0,imm=0) R7=map_value(id=0,off=0,ks=4,vs=1600,imm=0) R8_w=inv(id=0,smax_value=800) R9=inv800
; ksize = bpf_get_stack(ctx, raw_data + usize, max_len - usize, 0);
58: (1f) r9 -= r8
; ksize = bpf_get_stack(ctx, raw_data + usize, max_len - usize, 0);
59: (bf) r2 = r7
60: (0f) r2 += r1
regs=1 stack=0 before 52: (85) call bpf_get_stack#67
; ksize = bpf_get_stack(ctx, raw_data + usize, max_len - usize, 0);
61: (bf) r1 = r6
62: (bf) r3 = r9
63: (b7) r4 = 0
64: (85) call bpf_get_stack#67
 R0=inv(id=0,smax_value=800) R1_w=ctx(id=0,off=0,imm=0) R2_w=map_value(id=0,off=0,ks=4,vs=1600,umax_value=800,var_off=(0x0; 0x3ff),s32_max_value=1023,u32_max_value=1023) R3_w=inv(id=0,umax_value=9223372036854776608)
R3 unbounded memory access, use 'var &= const' or 'if (var < const)'

In the C code:
  usize = bpf_get_stack(ctx, raw_data, max_len, BPF_F_USER_STACK);
  if (usize < 0)
          return 0;

  ksize = bpf_get_stack(ctx, raw_data + usize, max_len - usize, 0);
  if (ksize < 0)
          return 0;

We used to have problem with pointer arith in R2.
Now it's a problem with two integers in R3.
'if (usize < 0)' is comparing R1 and makes it [0,800], but R8 stays [-inf,800].
Both registers represent the same 'usize' variable.
Then R9 -= R8 is doing 800 - [-inf, 800]
so the result of "max_len - usize" looks unbounded to the verifier while
it's obvious in C code that "max_len - usize" should be [0, 800].

To workaround the problem convert ksize and usize variables from int to long.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2020-06-24 11:10:59 -07:00
Andrii Nakryiko
192b6638ee libbpf: Prevent loading vmlinux BTF twice
Prevent loading/parsing vmlinux BTF twice in some cases: for CO-RE relocations
and for BTF-aware hooks (tp_btf, fentry/fexit, etc).

Fixes: a6ed02cac6 ("libbpf: Load btf_vmlinux only once per object.")
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200624043805.1794620-1-andriin@fb.com
2020-06-24 16:08:17 +02:00
Colin Ian King
135c783f47 libbpf: Fix spelling mistake "kallasyms" -> "kallsyms"
There is a spelling mistake in a pr_warn message. Fix it.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200623084207.149253-1-colin.king@canonical.com
2020-06-24 15:53:53 +02:00
Quentin Monnet
54b66c2255 tools, bpftool: Fix variable shadowing in emit_obj_refs_json()
Building bpftool yields the following complaint:

    pids.c: In function 'emit_obj_refs_json':
    pids.c:175:80: warning: declaration of 'json_wtr' shadows a global declaration [-Wshadow]
      175 | void emit_obj_refs_json(struct obj_refs_table *table, __u32 id, json_writer_t *json_wtr)
          |                                                                 ~~~~~~~~~~~~~~~^~~~~~~~
    In file included from pids.c:11:
    main.h:141:23: note: shadowed declaration is here
      141 | extern json_writer_t *json_wtr;
          |                       ^~~~~~~~

Let's rename the variable.

v2:
- Rename the variable instead of calling the global json_wtr directly.

Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200623213600.16643-1-quentin@isovalent.com
2020-06-24 15:46:28 +02:00
Mark Brown
cb944f02d0 kselftest: arm64: Remove redundant clean target
The arm64 signal tests generate warnings during build since both they and
the toplevel lib.mk define a clean target:

Makefile:25: warning: overriding recipe for target 'clean'
../../lib.mk:126: warning: ignoring old recipe for target 'clean'

Since the inclusion of lib.mk is in the signal Makefile there is no
situation where this warning could be avoided so just remove the redundant
clean target.

Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20200624104933.21125-1-broonie@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
2020-06-24 14:25:59 +01:00
tannerlove
0558c39604 selftests/net: plug rxtimestamp test into kselftest framework
Run rxtimestamp as part of TEST_PROGS. Analogous to other tests, add
new rxtimestamp.sh wrapper script, so that the test runs isolated
from background traffic in a private network namespace.

Also ignore failures of test case #6 by default. This case verifies
that a receive timestamp is not reported if timestamp reporting is
enabled for a socket, but generation is disabled. Receive timestamp
generation has to be enabled globally, as no associated socket is
known yet. A background process that enables rx timestamp generation
therefore causes a false positive. Ntpd is one example that does.

Add a "--strict" option to cause failure in the event that any test
case fails, including test #6. This is useful for environments that
are known to not have such background processes.

Tested:
make -C tools/testing/selftests TARGETS="net" run_tests

Signed-off-by: Tanner Love <tannerlove@google.com>
Acked-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-06-23 20:36:46 -07:00
Quentin Monnet
bcc7f554cf bpf: Fix formatting in documentation for BPF helpers
When producing the bpf-helpers.7 man page from the documentation from
the BPF user space header file, rst2man complains:

    <stdin>:2636: (ERROR/3) Unexpected indentation.
    <stdin>:2640: (WARNING/2) Block quote ends without a blank line; unexpected unindent.

Let's fix formatting for the relevant chunk (item list in
bpf_ringbuf_query()'s description), and for a couple other functions.

Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200623153935.6215-1-quentin@isovalent.com
2020-06-23 17:57:02 -07:00
Andrii Nakryiko
9c82a63cf3 libbpf: Fix CO-RE relocs against .text section
bpf_object__find_program_by_title(), used by CO-RE relocation code, doesn't
return .text "BPF program", if it is a function storage for sub-programs.
Because of that, any CO-RE relocation in helper non-inlined functions will
fail. Fix this by searching for .text-corresponding BPF program manually.

Adjust one of bpf_iter selftest to exhibit this pattern.

Fixes: ddc7c30426 ("libbpf: implement BPF CO-RE offset relocation algorithm")
Reported-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20200619230423.691274-1-andriin@fb.com
2020-06-23 17:01:43 -07:00
Alexei Starovoitov
4e608675e7 Merge up to bpf_probe_read_kernel_str() fix into bpf-next 2020-06-23 15:33:41 -07:00
Tobias Klauser
9d9d8cc21e tools, bpftool: Correctly evaluate $(BUILD_BPF_SKELS) in Makefile
Currently, if the clang-bpf-co-re feature is not available, the build
fails with e.g.

  CC       prog.o
prog.c:1462:10: fatal error: profiler.skel.h: No such file or directory
 1462 | #include "profiler.skel.h"
      |          ^~~~~~~~~~~~~~~~~

This is due to the fact that the BPFTOOL_WITHOUT_SKELETONS macro is not
defined, despite BUILD_BPF_SKELS not being set. Fix this by correctly
evaluating $(BUILD_BPF_SKELS) when deciding on whether to add
-DBPFTOOL_WITHOUT_SKELETONS to CFLAGS.

Fixes: 05aca6da3b ("tools/bpftool: Generalize BPF skeleton support and generate vmlinux.h")
Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200623103710.10370-1-tklauser@distanz.ch
2020-06-24 00:06:46 +02:00
John Fastabend
2fde1747c9 selftests/bpf: Add variable-length data concat pattern less than test
Extend original variable-length tests with a case to catch a common
existing pattern of testing for < 0 for errors. Note because
verifier also tracks upper bounds and we know it can not be greater
than MAX_LEN here we can skip upper bound check.

In ALU64 enabled compilation converting from long->int return types
in probe helpers results in extra instruction pattern, <<= 32, s >>= 32.
The trade-off is the non-ALU64 case works. If you really care about
every extra insn (XDP case?) then you probably should be using original
int type.

In addition adding a sext insn to bpf might help the verifier in the
general case to avoid these types of tricks.

Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200623032224.4020118-3-andriin@fb.com
2020-06-24 00:04:36 +02:00
Andrii Nakryiko
5e85c6bb8e selftests/bpf: Add variable-length data concatenation pattern test
Add selftest that validates variable-length data reading and concatentation
with one big shared data array. This is a common pattern in production use for
monitoring and tracing applications, that potentially can read a lot of data,
but overall read much less. Such pattern allows to determine precisely what
amount of data needs to be sent over perfbuf/ringbuf and maximize efficiency.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200623032224.4020118-2-andriin@fb.com
2020-06-24 00:04:36 +02:00
Andrii Nakryiko
bdb7b79b4c bpf: Switch most helper return values from 32-bit int to 64-bit long
Switch most of BPF helper definitions from returning int to long. These
definitions are coming from comments in BPF UAPI header and are used to
generate bpf_helper_defs.h (under libbpf) to be later included and used from
BPF programs.

In actual in-kernel implementation, all the helpers are defined as returning
u64, but due to some historical reasons, most of them are actually defined as
returning int in UAPI (usually, to return 0 on success, and negative value on
error).

This actually causes Clang to quite often generate sub-optimal code, because
compiler believes that return value is 32-bit, and in a lot of cases has to be
up-converted (usually with a pair of 32-bit bit shifts) to 64-bit values,
before they can be used further in BPF code.

Besides just "polluting" the code, these 32-bit shifts quite often cause
problems for cases in which return value matters. This is especially the case
for the family of bpf_probe_read_str() functions. There are few other similar
helpers (e.g., bpf_read_branch_records()), in which return value is used by
BPF program logic to record variable-length data and process it. For such
cases, BPF program logic carefully manages offsets within some array or map to
read variable-length data. For such uses, it's crucial for BPF verifier to
track possible range of register values to prove that all the accesses happen
within given memory bounds. Those extraneous zero-extending bit shifts,
inserted by Clang (and quite often interleaved with other code, which makes
the issues even more challenging and sometimes requires employing extra
per-variable compiler barriers), throws off verifier logic and makes it mark
registers as having unknown variable offset. We'll study this pattern a bit
later below.

Another common pattern is to check return of BPF helper for non-zero state to
detect error conditions and attempt alternative actions in such case. Even in
this simple and straightforward case, this 32-bit vs BPF's native 64-bit mode
quite often leads to sub-optimal and unnecessary extra code. We'll look at
this pattern as well.

Clang's BPF target supports two modes of code generation: ALU32, in which it
is capable of using lower 32-bit parts of registers, and no-ALU32, in which
only full 64-bit registers are being used. ALU32 mode somewhat mitigates the
above described problems, but not in all cases.

This patch switches all the cases in which BPF helpers return 0 or negative
error from returning int to returning long. It is shown below that such change
in definition leads to equivalent or better code. No-ALU32 mode benefits more,
but ALU32 mode doesn't degrade or still gets improved code generation.

Another class of cases switched from int to long are bpf_probe_read_str()-like
helpers, which encode successful case as non-negative values, while still
returning negative value for errors.

In all of such cases, correctness is preserved due to two's complement
encoding of negative values and the fact that all helpers return values with
32-bit absolute value. Two's complement ensures that for negative values
higher 32 bits are all ones and when truncated, leave valid negative 32-bit
value with the same value. Non-negative values have upper 32 bits set to zero
and similarly preserve value when high 32 bits are truncated. This means that
just casting to int/u32 is correct and efficient (and in ALU32 mode doesn't
require any extra shifts).

To minimize the chances of regressions, two code patterns were investigated,
as mentioned above. For both patterns, BPF assembly was analyzed in
ALU32/NO-ALU32 compiler modes, both with current 32-bit int return type and
new 64-bit long return type.

Case 1. Variable-length data reading and concatenation. This is quite
ubiquitous pattern in tracing/monitoring applications, reading data like
process's environment variables, file path, etc. In such case, many pieces of
string-like variable-length data are read into a single big buffer, and at the
end of the process, only a part of array containing actual data is sent to
user-space for further processing. This case is tested in test_varlen.c
selftest (in the next patch). Code flow is roughly as follows:

  void *payload = &sample->payload;
  u64 len;

  len = bpf_probe_read_kernel_str(payload, MAX_SZ1, &source_data1);
  if (len <= MAX_SZ1) {
      payload += len;
      sample->len1 = len;
  }
  len = bpf_probe_read_kernel_str(payload, MAX_SZ2, &source_data2);
  if (len <= MAX_SZ2) {
      payload += len;
      sample->len2 = len;
  }
  /* and so on */
  sample->total_len = payload - &sample->payload;
  /* send over, e.g., perf buffer */

There could be two variations with slightly different code generated: when len
is 64-bit integer and when it is 32-bit integer. Both variations were analysed.
BPF assembly instructions between two successive invocations of
bpf_probe_read_kernel_str() were used to check code regressions. Results are
below, followed by short analysis. Left side is using helpers with int return
type, the right one is after the switch to long.

ALU32 + INT                                ALU32 + LONG
===========                                ============

64-BIT (13 insns):                         64-BIT (10 insns):
------------------------------------       ------------------------------------
  17:   call 115                             17:   call 115
  18:   if w0 > 256 goto +9 <LBB0_4>         18:   if r0 > 256 goto +6 <LBB0_4>
  19:   w1 = w0                              19:   r1 = 0 ll
  20:   r1 <<= 32                            21:   *(u64 *)(r1 + 0) = r0
  21:   r1 s>>= 32                           22:   r6 = 0 ll
  22:   r2 = 0 ll                            24:   r6 += r0
  24:   *(u64 *)(r2 + 0) = r1              00000000000000c8 <LBB0_4>:
  25:   r6 = 0 ll                            25:   r1 = r6
  27:   r6 += r1                             26:   w2 = 256
00000000000000e0 <LBB0_4>:                   27:   r3 = 0 ll
  28:   r1 = r6                              29:   call 115
  29:   w2 = 256
  30:   r3 = 0 ll
  32:   call 115

32-BIT (11 insns):                         32-BIT (12 insns):
------------------------------------       ------------------------------------
  17:   call 115                             17:   call 115
  18:   if w0 > 256 goto +7 <LBB1_4>         18:   if w0 > 256 goto +8 <LBB1_4>
  19:   r1 = 0 ll                            19:   r1 = 0 ll
  21:   *(u32 *)(r1 + 0) = r0                21:   *(u32 *)(r1 + 0) = r0
  22:   w1 = w0                              22:   r0 <<= 32
  23:   r6 = 0 ll                            23:   r0 >>= 32
  25:   r6 += r1                             24:   r6 = 0 ll
00000000000000d0 <LBB1_4>:                   26:   r6 += r0
  26:   r1 = r6                            00000000000000d8 <LBB1_4>:
  27:   w2 = 256                             27:   r1 = r6
  28:   r3 = 0 ll                            28:   w2 = 256
  30:   call 115                             29:   r3 = 0 ll
                                             31:   call 115

In ALU32 mode, the variant using 64-bit length variable clearly wins and
avoids unnecessary zero-extension bit shifts. In practice, this is even more
important and good, because BPF code won't need to do extra checks to "prove"
that payload/len are within good bounds.

32-bit len is one instruction longer. Clang decided to do 64-to-32 casting
with two bit shifts, instead of equivalent `w1 = w0` assignment. The former
uses extra register. The latter might potentially lose some range information,
but not for 32-bit value. So in this case, verifier infers that r0 is [0, 256]
after check at 18:, and shifting 32 bits left/right keeps that range intact.
We should probably look into Clang's logic and see why it chooses bitshifts
over sub-register assignments for this.

NO-ALU32 + INT                             NO-ALU32 + LONG
==============                             ===============

64-BIT (14 insns):                         64-BIT (10 insns):
------------------------------------       ------------------------------------
  17:   call 115                             17:   call 115
  18:   r0 <<= 32                            18:   if r0 > 256 goto +6 <LBB0_4>
  19:   r1 = r0                              19:   r1 = 0 ll
  20:   r1 >>= 32                            21:   *(u64 *)(r1 + 0) = r0
  21:   if r1 > 256 goto +7 <LBB0_4>         22:   r6 = 0 ll
  22:   r0 s>>= 32                           24:   r6 += r0
  23:   r1 = 0 ll                          00000000000000c8 <LBB0_4>:
  25:   *(u64 *)(r1 + 0) = r0                25:   r1 = r6
  26:   r6 = 0 ll                            26:   r2 = 256
  28:   r6 += r0                             27:   r3 = 0 ll
00000000000000e8 <LBB0_4>:                   29:   call 115
  29:   r1 = r6
  30:   r2 = 256
  31:   r3 = 0 ll
  33:   call 115

32-BIT (13 insns):                         32-BIT (13 insns):
------------------------------------       ------------------------------------
  17:   call 115                             17:   call 115
  18:   r1 = r0                              18:   r1 = r0
  19:   r1 <<= 32                            19:   r1 <<= 32
  20:   r1 >>= 32                            20:   r1 >>= 32
  21:   if r1 > 256 goto +6 <LBB1_4>         21:   if r1 > 256 goto +6 <LBB1_4>
  22:   r2 = 0 ll                            22:   r2 = 0 ll
  24:   *(u32 *)(r2 + 0) = r0                24:   *(u32 *)(r2 + 0) = r0
  25:   r6 = 0 ll                            25:   r6 = 0 ll
  27:   r6 += r1                             27:   r6 += r1
00000000000000e0 <LBB1_4>:                 00000000000000e0 <LBB1_4>:
  28:   r1 = r6                              28:   r1 = r6
  29:   r2 = 256                             29:   r2 = 256
  30:   r3 = 0 ll                            30:   r3 = 0 ll
  32:   call 115                             32:   call 115

In NO-ALU32 mode, for the case of 64-bit len variable, Clang generates much
superior code, as expected, eliminating unnecessary bit shifts. For 32-bit
len, code is identical.

So overall, only ALU-32 32-bit len case is more-or-less equivalent and the
difference stems from internal Clang decision, rather than compiler lacking
enough information about types.

Case 2. Let's look at the simpler case of checking return result of BPF helper
for errors. The code is very simple:

  long bla;
  if (bpf_probe_read_kenerl(&bla, sizeof(bla), 0))
      return 1;
  else
      return 0;

ALU32 + CHECK (9 insns)                    ALU32 + CHECK (9 insns)
====================================       ====================================
  0:    r1 = r10                             0:    r1 = r10
  1:    r1 += -8                             1:    r1 += -8
  2:    w2 = 8                               2:    w2 = 8
  3:    r3 = 0                               3:    r3 = 0
  4:    call 113                             4:    call 113
  5:    w1 = w0                              5:    r1 = r0
  6:    w0 = 1                               6:    w0 = 1
  7:    if w1 != 0 goto +1 <LBB2_2>          7:    if r1 != 0 goto +1 <LBB2_2>
  8:    w0 = 0                               8:    w0 = 0
0000000000000048 <LBB2_2>:                 0000000000000048 <LBB2_2>:
  9:    exit                                 9:    exit

Almost identical code, the only difference is the use of full register
assignment (r1 = r0) vs half-registers (w1 = w0) in instruction #5. On 32-bit
architectures, new BPF assembly might be slightly less optimal, in theory. But
one can argue that's not a big issue, given that use of full registers is
still prevalent (e.g., for parameter passing).

NO-ALU32 + CHECK (11 insns)                NO-ALU32 + CHECK (9 insns)
====================================       ====================================
  0:    r1 = r10                             0:    r1 = r10
  1:    r1 += -8                             1:    r1 += -8
  2:    r2 = 8                               2:    r2 = 8
  3:    r3 = 0                               3:    r3 = 0
  4:    call 113                             4:    call 113
  5:    r1 = r0                              5:    r1 = r0
  6:    r1 <<= 32                            6:    r0 = 1
  7:    r1 >>= 32                            7:    if r1 != 0 goto +1 <LBB2_2>
  8:    r0 = 1                               8:    r0 = 0
  9:    if r1 != 0 goto +1 <LBB2_2>        0000000000000048 <LBB2_2>:
 10:    r0 = 0                               9:    exit
0000000000000058 <LBB2_2>:
 11:    exit

NO-ALU32 is a clear improvement, getting rid of unnecessary zero-extension bit
shifts.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200623032224.4020118-1-andriin@fb.com
2020-06-24 00:04:36 +02:00
Jason A. Donenfeld
900575aa33 wireguard: device: avoid circular netns references
Before, we took a reference to the creating netns if the new netns was
different. This caused issues with circular references, with two
wireguard interfaces swapping namespaces. The solution is to rather not
take any extra references at all, but instead simply invalidate the
creating netns pointer when that netns is deleted.

In order to prevent this from happening again, this commit improves the
rough object leak tracking by allowing it to account for created and
destroyed interfaces, aside from just peers and keys. That then makes it
possible to check for the object leak when having two interfaces take a
reference to each others' namespaces.

Fixes: e7096c131e ("net: WireGuard secure network tunnel")
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-06-23 14:50:34 -07:00
Andrii Nakryiko
075c776658 tools/bpftool: Add documentation and sample output for process info
Add statements about bpftool being able to discover process info, holding
reference to BPF map, prog, link, or BTF. Show example output as well.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/20200619231703.738941-10-andriin@fb.com
2020-06-22 17:01:49 -07:00
Andrii Nakryiko
d53dee3fe0 tools/bpftool: Show info for processes holding BPF map/prog/link/btf FDs
Add bpf_iter-based way to find all the processes that hold open FDs against
BPF object (map, prog, link, btf). bpftool always attempts to discover this,
but will silently give up if kernel doesn't yet support bpf_iter BPF programs.
Process name and PID are emitted for each process (task group).

Sample output for each of 4 BPF objects:

$ sudo ./bpftool prog show
2694: cgroup_device  tag 8c42dee26e8cd4c2  gpl
        loaded_at 2020-06-16T15:34:32-0700  uid 0
        xlated 648B  jited 409B  memlock 4096B
        pids systemd(1)
2907: cgroup_skb  name egress  tag 9ad187367cf2b9e8  gpl
        loaded_at 2020-06-16T18:06:54-0700  uid 0
        xlated 48B  jited 59B  memlock 4096B  map_ids 2436
        btf_id 1202
        pids test_progs(2238417), test_progs(2238445)

$ sudo ./bpftool map show
2436: array  name test_cgr.bss  flags 0x400
        key 4B  value 8B  max_entries 1  memlock 8192B
        btf_id 1202
        pids test_progs(2238417), test_progs(2238445)
2445: array  name pid_iter.rodata  flags 0x480
        key 4B  value 4B  max_entries 1  memlock 8192B
        btf_id 1214  frozen
        pids bpftool(2239612)

$ sudo ./bpftool link show
61: cgroup  prog 2908
        cgroup_id 375301  attach_type egress
        pids test_progs(2238417), test_progs(2238445)
62: cgroup  prog 2908
        cgroup_id 375344  attach_type egress
        pids test_progs(2238417), test_progs(2238445)

$ sudo ./bpftool btf show
1202: size 1527B  prog_ids 2908,2907  map_ids 2436
        pids test_progs(2238417), test_progs(2238445)
1242: size 34684B
        pids bpftool(2258892)

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/20200619231703.738941-9-andriin@fb.com
2020-06-22 17:01:49 -07:00
Andrii Nakryiko
bd9bedf84b libbpf: Wrap source argument of BPF_CORE_READ macro in parentheses
Wrap source argument of BPF_CORE_READ family of macros into parentheses to
allow uses like this:

BPF_CORE_READ((struct cast_struct *)src, a, b, c);

Fixes: 7db3822ab9 ("libbpf: Add BPF_CORE_READ/BPF_CORE_READ_INTO helpers")
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200619231703.738941-8-andriin@fb.com
2020-06-22 17:01:48 -07:00
Andrii Nakryiko
05aca6da3b tools/bpftool: Generalize BPF skeleton support and generate vmlinux.h
Adapt Makefile to support BPF skeleton generation beyond single profiler.bpf.c
case. Also add vmlinux.h generation and switch profiler.bpf.c to use it.

clang-bpf-global-var feature is extended and renamed to clang-bpf-co-re to
check for support of preserve_access_index attribute, which, together with BTF
for global variables, is the minimum requirement for modern BPF programs.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/20200619231703.738941-7-andriin@fb.com
2020-06-22 17:01:48 -07:00
Andrii Nakryiko
16e9b187ab tools/bpftool: Minimize bootstrap bpftool
Build minimal "bootstrap mode" bpftool to enable skeleton (and, later,
vmlinux.h generation), instead of building almost complete, but slightly
different (w/o skeletons, etc) bpftool to bootstrap complete bpftool build.

Current approach doesn't scale well (engineering-wise) when adding more BPF
programs to bpftool and other complicated functionality, as it requires
constant adjusting of the code to work in both bootstrapped mode and normal
mode.

So it's better to build only minimal bpftool version that supports only BPF
skeleton code generation and BTF-to-C conversion. Thankfully, this is quite
easy to accomplish due to internal modularity of bpftool commands. This will
also allow to keep adding new functionality to bpftool in general, without the
need to care about bootstrap mode for those new parts of bpftool.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/20200619231703.738941-6-andriin@fb.com
2020-06-22 17:01:48 -07:00
Andrii Nakryiko
a479b8ce4e tools/bpftool: Move map/prog parsing logic into common
Move functions that parse map and prog by id/tag/name/etc outside of
map.c/prog.c, respectively. These functions are used outside of those files
and are generic enough to be in common. This also makes heavy-weight map.c and
prog.c more decoupled from the rest of bpftool files and facilitates more
lightweight bootstrap bpftool variant.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/20200619231703.738941-5-andriin@fb.com
2020-06-22 17:01:48 -07:00
Andrii Nakryiko
b7ddfab20a selftests/bpf: Add __ksym extern selftest
Validate libbpf is able to handle weak and strong kernel symbol externs in BPF
code correctly.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Reviewed-by: Hao Luo <haoluo@google.com>
Link: https://lore.kernel.org/bpf/20200619231703.738941-4-andriin@fb.com
2020-06-22 17:01:48 -07:00
Andrii Nakryiko
1c0c7074fe libbpf: Add support for extracting kernel symbol addresses
Add support for another (in addition to existing Kconfig) special kind of
externs in BPF code, kernel symbol externs. Such externs allow BPF code to
"know" kernel symbol address and either use it for comparisons with kernel
data structures (e.g., struct file's f_op pointer, to distinguish different
kinds of file), or, with the help of bpf_probe_user_kernel(), to follow
pointers and read data from global variables. Kernel symbol addresses are
found through /proc/kallsyms, which should be present in the system.

Currently, such kernel symbol variables are typeless: they have to be defined
as `extern const void <symbol>` and the only operation you can do (in C code)
with them is to take its address. Such extern should reside in a special
section '.ksyms'. bpf_helpers.h header provides __ksym macro for this. Strong
vs weak semantics stays the same as with Kconfig externs. If symbol is not
found in /proc/kallsyms, this will be a failure for strong (non-weak) extern,
but will be defaulted to 0 for weak externs.

If the same symbol is defined multiple times in /proc/kallsyms, then it will
be error if any of the associated addresses differs. In that case, address is
ambiguous, so libbpf falls on the side of caution, rather than confusing user
with randomly chosen address.

In the future, once kernel is extended with variables BTF information, such
ksym externs will be supported in a typed version, which will allow BPF
program to read variable's contents directly, similarly to how it's done for
fentry/fexit input arguments.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Reviewed-by: Hao Luo <haoluo@google.com>
Link: https://lore.kernel.org/bpf/20200619231703.738941-3-andriin@fb.com
2020-06-22 17:01:48 -07:00
Andrii Nakryiko
2e33efe32e libbpf: Generalize libbpf externs support
Switch existing Kconfig externs to be just one of few possible kinds of more
generic externs. This refactoring is in preparation for ksymbol extern
support, added in the follow up patch. There are no functional changes
intended.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Reviewed-by: Hao Luo <haoluo@google.com>
Link: https://lore.kernel.org/bpf/20200619231703.738941-2-andriin@fb.com
2020-06-22 17:01:48 -07:00
Petr Machata
13bd5d0256 selftests: forwarding: Add a test for pedit munge tcp, udp sport, dport
Add a test that checks that pedit adjusts port numbers of tcp and udp
packets.

Signed-off-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-06-22 16:32:11 -07:00
Andrii Nakryiko
1bdb6c9a1c libbpf: Add a bunch of attribute getters/setters for map definitions
Add a bunch of getter for various aspects of BPF map. Some of these attribute
(e.g., key_size, value_size, type, etc) are available right now in struct
bpf_map_def, but this patch adds getter allowing to fetch them individually.
bpf_map_def approach isn't very scalable, when ABI stability requirements are
taken into account. It's much easier to extend libbpf and add support for new
features, when each aspect of BPF map has separate getter/setter.

Getters follow the common naming convention of not explicitly having "get" in
its name: bpf_map__type() returns map type, bpf_map__key_size() returns
key_size. Setters, though, explicitly have set in their name:
bpf_map__set_type(), bpf_map__set_key_size().

This patch ensures we now have a getter and a setter for the following
map attributes:
  - type;
  - max_entries;
  - map_flags;
  - numa_node;
  - key_size;
  - value_size;
  - ifindex.

bpf_map__resize() enforces unnecessary restriction of max_entries > 0. It is
unnecessary, because libbpf actually supports zero max_entries for some cases
(e.g., for PERF_EVENT_ARRAY map) and treats it specially during map creation
time. To allow setting max_entries=0, new bpf_map__set_max_entries() setter is
added. bpf_map__resize()'s behavior is preserved for backwards compatibility
reasons.

Map ifindex getter is added as well. There is a setter already, but no
corresponding getter. Fix this assymetry as well. bpf_map__set_ifindex()
itself is converted from void function into error-returning one, similar to
other setters. The only error returned right now is -EBUSY, if BPF map is
already loaded and has corresponding FD.

One lacking attribute with no ability to get/set or even specify it
declaratively is numa_node. This patch fixes this gap and both adds
programmatic getter/setter, as well as adds support for numa_node field in
BTF-defined map.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/bpf/20200621062112.3006313-1-andriin@fb.com
2020-06-23 00:01:32 +02:00
Andrii Nakryiko
4e15507fea libbpf: Forward-declare bpf_stats_type for systems with outdated UAPI headers
Systems that doesn't yet have the very latest linux/bpf.h header, enum
bpf_stats_type will be undefined, causing compilation warnings. Prevents this
by forward-declaring enum.

Fixes: 0bee106716 ("libbpf: Add support for command BPF_ENABLE_STATS")
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20200621031159.2279101-1-andriin@fb.com
2020-06-22 23:23:49 +02:00
Andrey Ignatov
b1b53d413f selftests/bpf: Test access to bpf map pointer
Add selftests to test access to map pointers from bpf program for all
map types except struct_ops (that one would need additional work).

verifier test focuses mostly on scenarios that must be rejected.

prog_tests test focuses on accessing multiple fields both scalar and a
nested struct from bpf program and verifies that those fields have
expected values.

Signed-off-by: Andrey Ignatov <rdna@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/139a6a17f8016491e39347849b951525335c6eb4.1592600985.git.rdna@fb.com
2020-06-22 22:22:59 +02:00
Andrey Ignatov
41c48f3a98 bpf: Support access to bpf map fields
There are multiple use-cases when it's convenient to have access to bpf
map fields, both `struct bpf_map` and map type specific struct-s such as
`struct bpf_array`, `struct bpf_htab`, etc.

For example while working with sock arrays it can be necessary to
calculate the key based on map->max_entries (some_hash % max_entries).
Currently this is solved by communicating max_entries via "out-of-band"
channel, e.g. via additional map with known key to get info about target
map. That works, but is not very convenient and error-prone while
working with many maps.

In other cases necessary data is dynamic (i.e. unknown at loading time)
and it's impossible to get it at all. For example while working with a
hash table it can be convenient to know how much capacity is already
used (bpf_htab.count.counter for BPF_F_NO_PREALLOC case).

At the same time kernel knows this info and can provide it to bpf
program.

Fill this gap by adding support to access bpf map fields from bpf
program for both `struct bpf_map` and map type specific fields.

Support is implemented via btf_struct_access() so that a user can define
their own `struct bpf_map` or map type specific struct in their program
with only necessary fields and preserve_access_index attribute, cast a
map to this struct and use a field.

For example:

	struct bpf_map {
		__u32 max_entries;
	} __attribute__((preserve_access_index));

	struct bpf_array {
		struct bpf_map map;
		__u32 elem_size;
	} __attribute__((preserve_access_index));

	struct {
		__uint(type, BPF_MAP_TYPE_ARRAY);
		__uint(max_entries, 4);
		__type(key, __u32);
		__type(value, __u32);
	} m_array SEC(".maps");

	SEC("cgroup_skb/egress")
	int cg_skb(void *ctx)
	{
		struct bpf_array *array = (struct bpf_array *)&m_array;
		struct bpf_map *map = (struct bpf_map *)&m_array;

		/* .. use map->max_entries or array->map.max_entries .. */
	}

Similarly to other btf_struct_access() use-cases (e.g. struct tcp_sock
in net/ipv4/bpf_tcp_ca.c) the patch allows access to any fields of
corresponding struct. Only reading from map fields is supported.

For btf_struct_access() to work there should be a way to know btf id of
a struct that corresponds to a map type. To get btf id there should be a
way to get a stringified name of map-specific struct, such as
"bpf_array", "bpf_htab", etc for a map type. Two new fields are added to
`struct bpf_map_ops` to handle it:
* .map_btf_name keeps a btf name of a struct returned by map_alloc();
* .map_btf_id is used to cache btf id of that struct.

To make btf ids calculation cheaper they're calculated once while
preparing btf_vmlinux and cached same way as it's done for btf_id field
of `struct bpf_func_proto`

While calculating btf ids, struct names are NOT checked for collision.
Collisions will be checked as a part of the work to prepare btf ids used
in verifier in compile time that should land soon. The only known
collision for `struct bpf_htab` (kernel/bpf/hashtab.c vs
net/core/sock_map.c) was fixed earlier.

Both new fields .map_btf_name and .map_btf_id must be set for a map type
for the feature to work. If neither is set for a map type, verifier will
return ENOTSUPP on a try to access map_ptr of corresponding type. If
just one of them set, it's verifier misconfiguration.

Only `struct bpf_array` for BPF_MAP_TYPE_ARRAY and `struct bpf_htab` for
BPF_MAP_TYPE_HASH are supported by this patch. Other map types will be
supported separately.

The feature is available only for CONFIG_DEBUG_INFO_BTF=y and gated by
perfmon_capable() so that unpriv programs won't have access to bpf map
fields.

Signed-off-by: Andrey Ignatov <rdna@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/6479686a0cd1e9067993df57b4c3eef0e276fec9.1592600985.git.rdna@fb.com
2020-06-22 22:22:58 +02:00
Linus Torvalds
dd0d718152 spi: Fixes for v5.8
Quite a lot of fixes here for no single reason.  There's a collection of
 the usual sort of device specific fixes and also a bunch of people have
 been working on spidev and the userspace test program spidev_test so
 they've got an unusually large collection of small fixes.
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Merge tag 'spi-fix-v5.8-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi

Pull spi fixes from Mark Brown:
 "Quite a lot of fixes here for no single reason.

  There's a collection of the usual sort of device specific fixes and
  also a bunch of people have been working on spidev and the userspace
  test program spidev_test so they've got an unusually large collection
  of small fixes"

* tag 'spi-fix-v5.8-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi:
  spi: spidev: fix a potential use-after-free in spidev_release()
  spi: spidev: fix a race between spidev_release and spidev_remove
  spi: stm32-qspi: Fix error path in case of -EPROBE_DEFER
  spi: uapi: spidev: Use TABs for alignment
  spi: spi-fsl-dspi: Free DMA memory with matching function
  spi: tools: Add macro definitions to fix build errors
  spi: tools: Make default_tx/rx and input_tx static
  spi: dt-bindings: amlogic, meson-gx-spicc: Fix schema for meson-g12a
  spi: rspi: Use requested instead of maximum bit rate
  spi: spidev_test: Use %u to format unsigned numbers
  spi: sprd: switch the sequence of setting WDG_LOAD_LOW and _HIGH
2020-06-22 09:49:59 -07:00
Eugenio Pérez
cb91909e48 tools/virtio: Use tools/include/list.h instead of stubs
It should not make any significant difference but reduce stub code.

Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Link: https://lore.kernel.org/r/20200418102217.32327-9-eperezma@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-06-22 12:34:22 -04:00
Eugenio Pérez
1d8bf5c3a3 tools/virtio: Reset index in virtio_test --reset.
This way behavior for vhost is more like a VM.

Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Link: https://lore.kernel.org/r/20200418102217.32327-8-eperezma@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-06-22 12:34:22 -04:00
Eugenio Pérez
6741239260 tools/virtio: Extract virtqueue initialization in vq_reset
So we can reset after that in the main loop.

Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Link: https://lore.kernel.org/r/20200418102217.32327-7-eperezma@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-06-22 12:34:22 -04:00
Eugenio Pérez
4cfb939353 tools/virtio: Use __vring_new_virtqueue in virtio_test.c
As updated in ("2a2d1382fe9d virtio: Add improved queue allocation API")

Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Link: https://lore.kernel.org/r/20200418102217.32327-6-eperezma@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-06-22 12:34:22 -04:00
Eugenio Pérez
264ee5aa81 tools/virtio: Add --reset
Currently, it only removes and add backend, but it will reset vq
position in future commits.

Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Link: https://lore.kernel.org/r/20200418102217.32327-5-eperezma@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-06-22 12:34:21 -04:00
Eugenio Pérez
7add78b2a6 tools/virtio: Add --batch=random option
So we can test with non-deterministic batches in flight.

Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Link: https://lore.kernel.org/r/20200418102217.32327-4-eperezma@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-06-22 12:34:21 -04:00
Eugenio Pérez
633fae33d5 tools/virtio: Add --batch option
This allow to test vhost having >1 buffers in flight

Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Link: https://lore.kernel.org/r/20200401183118.8334-5-eperezma@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Link: https://lore.kernel.org/r/20200418102217.32327-3-eperezma@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-06-22 12:34:21 -04:00
Andreas Gerstmayr
c42ad5d435 perf flamegraph: Explicitly set utf-8 encoding
On some platforms the default encoding is not utf-8, which causes an
UnicodeDecodeError when reading the flamegraph template and writing the
flamegraph

Signed-off-by: Andreas Gerstmayr <agerstmayr@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20200619153232.203537-1-agerstmayr@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-06-22 13:30:55 -03:00
Hangbin Liu
54eeea0d70 tc-testing: update geneve options match in tunnel_key unit tests
Since iproute2 commit f72c3ad00f3b ("tc: m_tunnel_key: add options
support for vxlan"), the geneve opt output use key word "geneve_opts"
instead of "geneve_opt". To make compatibility for both old and new
iproute2, let's accept both "geneve_opt" and "geneve_opts".

Suggested-by: Davide Caratti <dcaratti@redhat.com>
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Reviewed-by: Simon Horman <simon.horman@netronome.com>
Tested-by: Davide Caratti <dcaratti@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-06-20 17:35:18 -07:00
Andrea Mayer
8735e6eaa4 selftests: add selftest for the VRF strict mode
The new strict mode functionality is tested in different configurations and
on different network namespaces.

Signed-off-by: Andrea Mayer <andrea.mayer@uniroma2.it>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-06-20 17:22:23 -07:00
Linus Torvalds
8b6ddd10d6 A few fixes and small cleanups for tracing:
- Have recordmcount work with > 64K sections (to support LTO)
  - kprobe RCU fixes
  - Correct a kprobe critical section with missing mutex
  - Remove redundant arch_disarm_kprobe() call
  - Fix lockup when kretprobe triggers within kprobe_flush_task()
  - Fix memory leak in fetch_op_data operations
  - Fix sleep in atomic in ftrace trace array sample code
  - Free up memory on failure in sample trace array code
  - Fix incorrect reporting of function_graph fields in format file
  - Fix quote within quote parsing in bootconfig
  - Fix return value of bootconfig tool
  - Add testcases for bootconfig tool
  - Fix maybe uninitialized warning in ftrace pid file code
  - Remove unused variable in tracing_iter_reset()
  - Fix some typos
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Merge tag 'trace-v5.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fixes from Steven Rostedt:

 - Have recordmcount work with > 64K sections (to support LTO)

 - kprobe RCU fixes

 - Correct a kprobe critical section with missing mutex

 - Remove redundant arch_disarm_kprobe() call

 - Fix lockup when kretprobe triggers within kprobe_flush_task()

 - Fix memory leak in fetch_op_data operations

 - Fix sleep in atomic in ftrace trace array sample code

 - Free up memory on failure in sample trace array code

 - Fix incorrect reporting of function_graph fields in format file

 - Fix quote within quote parsing in bootconfig

 - Fix return value of bootconfig tool

 - Add testcases for bootconfig tool

 - Fix maybe uninitialized warning in ftrace pid file code

 - Remove unused variable in tracing_iter_reset()

 - Fix some typos

* tag 'trace-v5.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  ftrace: Fix maybe-uninitialized compiler warning
  tools/bootconfig: Add testcase for show-command and quotes test
  tools/bootconfig: Fix to return 0 if succeeded to show the bootconfig
  tools/bootconfig: Fix to use correct quotes for value
  proc/bootconfig: Fix to use correct quotes for value
  tracing: Remove unused event variable in tracing_iter_reset
  tracing/probe: Fix memleak in fetch_op_data operations
  trace: Fix typo in allocate_ftrace_ops()'s comment
  tracing: Make ftrace packed events have align of 1
  sample-trace-array: Remove trace_array 'sample-instance'
  sample-trace-array: Fix sleeping function called from invalid context
  kretprobe: Prevent triggering kretprobe from within kprobe_flush_task
  kprobes: Remove redundant arch_disarm_kprobe() call
  kprobes: Fix to protect kick_kprobe_optimizer() by kprobe_mutex
  kprobes: Use non RCU traversal APIs on kprobe_tables if possible
  kprobes: Suppress the suspicious RCU warning on kprobes
  recordmcount: support >64k sections
2020-06-20 13:17:47 -07:00
Linus Torvalds
1566feea45 s390 fixes for 5.8-rc2
- Few ptrace fixes mostly for strace and seccomp_bpf kernel tests
   findings.
 
 - Cleanup unused pm callbacks in virtio ccw.
 
 - Replace kmalloc + memset with kzalloc in crypto.
 
 - Use $(LD) for vDSO linkage to make clang happy.
 
 - Fix vDSO clock_getres() to preserve the same behaviour as
   posix_get_hrtimer_res().
 
 - Fix workqueue cpumask warning when NUMA=n and nr_node_ids=2.
 
 - Reduce SLSB writes during input processing, improve warnings and
   cleanup qdio_data usage in qdio.
 
 - Few fixes to use scnprintf() instead of snprintf().
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Merge tag 's390-5.8-2' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

Pull s390 fixes from Vasily Gorbik:

 - a few ptrace fixes mostly for strace and seccomp_bpf kernel tests
   findings

 - cleanup unused pm callbacks in virtio ccw

 - replace kmalloc + memset with kzalloc in crypto

 - use $(LD) for vDSO linkage to make clang happy

 - fix vDSO clock_getres() to preserve the same behaviour as
   posix_get_hrtimer_res()

 - fix workqueue cpumask warning when NUMA=n and nr_node_ids=2

 - reduce SLSB writes during input processing, improve warnings and
   cleanup qdio_data usage in qdio

 - a few fixes to use scnprintf() instead of snprintf()

* tag 's390-5.8-2' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
  s390: fix syscall_get_error for compat processes
  s390/qdio: warn about unexpected SLSB states
  s390/qdio: clean up usage of qdio_data
  s390/numa: let NODES_SHIFT depend on NEED_MULTIPLE_NODES
  s390/vdso: fix vDSO clock_getres()
  s390/vdso: Use $(LD) instead of $(CC) to link vDSO
  s390/protvirt: use scnprintf() instead of snprintf()
  s390: use scnprintf() in sys_##_prefix##_##_name##_show
  s390/crypto: use scnprintf() instead of snprintf()
  s390/zcrypt: use kzalloc
  s390/virtio: remove unused pm callbacks
  s390/qdio: reduce SLSB writes during Input Queue processing
  selftests/seccomp: s390 shares the syscall and return value register
  s390/ptrace: fix setting syscall number
  s390/ptrace: pass invalid syscall numbers to tracing
  s390/ptrace: return -ENOSYS when invalid syscall is supplied
  s390/seccomp: pass syscall arguments via seccomp_data
  s390/qdio: fine-tune SLSB update
2020-06-20 12:31:08 -07:00
Linus Torvalds
27c2760561 linux-kselftest-5.8-rc2
This Kselftest update for Linux 5.8-rc2 consists of:
 
 - ftrace "requires:" list for simplifying and unifying requirement
   checks for each test case, adding "requires:" line instead of
   checking required ftrace interfaces in each test case.
 - a minor spelling correction patch
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Merge tag 'linux-kselftest-5.8-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest

Pull kselftest cleanups from Shuah Khan:

 - ftrace "requires:" list for simplifying and unifying requirement
   checks for each test case, adding "requires:" line instead of
   checking required ftrace interfaces in each test case.

 - a minor spelling correction patch

* tag 'linux-kselftest-5.8-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest:
  selftests/ftrace: Support ":README" suffix for requires
  selftests/ftrace: Support ":tracer" suffix for requires
  selftests/ftrace: Convert check_filter_file() with requires list
  selftests/ftrace: Convert required interface checks into requires list
  selftests/ftrace: Add "requires:" list support
  selftests/ftrace: Return unsupported for the unconfigured features
  selftests/ftrace: Allow ":" in description
  tools: testing: ftrace: trigger: fix spelling mistake
2020-06-20 12:10:09 -07:00
Willem de Bruijn
ca8826095e selftests/net: report etf errors correctly
The ETF qdisc can queue skbs that it could not pace on the errqueue.

Address a few issues in the selftest

- recv buffer size was too small, and incorrectly calculated
- compared errno to ee_code instead of ee_errno
- missed invalid request error type

v2:
  - fix a few checkpatch --strict indentation warnings

Fixes: ea6a547669 ("selftests/net: make so_txtime more robust to timer variance")
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-06-19 20:23:02 -07:00
Andrii Nakryiko
bb8dc2695a tools/bpftool: Relicense bpftool's BPF profiler prog as dual-license GPL/BSD
Relicense it to be compatible with the rest of bpftool files.

Suggested-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200619222024.519774-1-andriin@fb.com
2020-06-20 00:27:19 +02:00
Yonghong Song
d56b74b9e1 tools/bpf: Add verifier tests for 32bit pointer/scalar arithmetic
Added two test_verifier subtests for 32bit pointer/scalar arithmetic
with BPF_SUB operator. They are passing verifier now.

Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200618234632.3321367-1-yhs@fb.com
2020-06-19 23:34:43 +02:00
Peter Zijlstra
0f1441b44e objtool: Fix noinstr vs KCOV
Since many compilers cannot disable KCOV with a function attribute,
help it to NOP out any __sanitizer_cov_*() calls injected in noinstr
code.

This turns:

12:   e8 00 00 00 00          callq  17 <lockdep_hardirqs_on+0x17>
		13: R_X86_64_PLT32      __sanitizer_cov_trace_pc-0x4

into:

12:   0f 1f 44 00 00          nopl   0x0(%rax,%rax,1)
		13: R_X86_64_NONE      __sanitizer_cov_trace_pc-0x4

Just like recordmcount does.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Dmitry Vyukov <dvyukov@google.com>
2020-06-18 17:36:33 +02:00
Peter Zijlstra
fdabdd0b05 objtool: Provide elf_write_{insn,reloc}()
This provides infrastructure to rewrite instructions; this is
immediately useful for helping out with KCOV-vs-noinstr, but will
also come in handy for a bunch of variable sized jump-label patches
that are still on ice.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
2020-06-18 17:36:33 +02:00