Commit Graph

306 Commits

Author SHA1 Message Date
Vincent Whitchurch
2a4a62a14b um: Fix out-of-bounds read in LDT setup
syscall_stub_data() expects the data_count parameter to be the number of
longs, not bytes.

 ==================================================================
 BUG: KASAN: stack-out-of-bounds in syscall_stub_data+0x70/0xe0
 Read of size 128 at addr 000000006411f6f0 by task swapper/1

 CPU: 0 PID: 1 Comm: swapper Not tainted 5.18.0+ #18
 Call Trace:
  show_stack.cold+0x166/0x2a7
  __dump_stack+0x3a/0x43
  dump_stack_lvl+0x1f/0x27
  print_report.cold+0xdb/0xf81
  kasan_report+0x119/0x1f0
  kasan_check_range+0x3a3/0x440
  memcpy+0x52/0x140
  syscall_stub_data+0x70/0xe0
  write_ldt_entry+0xac/0x190
  init_new_ldt+0x515/0x960
  init_new_context+0x2c4/0x4d0
  mm_init.constprop.0+0x5ed/0x760
  mm_alloc+0x118/0x170
  0x60033f48
  do_one_initcall+0x1d7/0x860
  0x60003e7b
  kernel_init+0x6e/0x3d4
  new_thread_handler+0x1e7/0x2c0

 The buggy address belongs to stack of task swapper/1
  and is located at offset 64 in frame:
  init_new_ldt+0x0/0x960

 This frame has 2 objects:
  [32, 40) 'addr'
  [64, 80) 'desc'
 ==================================================================

Fixes: 858259cf7d ("uml: maintain own LDT entries")
Signed-off-by: Vincent Whitchurch <vincent.whitchurch@axis.com>
Cc: stable@vger.kernel.org
Signed-off-by: Richard Weinberger <richard@nod.at>
2022-05-27 09:03:41 +02:00
Linus Torvalds
88e6c02076 Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs updates from Al Viro:
 "Assorted bits and pieces"

* 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  aio: drop needless assignment in aio_read()
  clean overflow checks in count_mounts() a bit
  seq_file: fix NULL pointer arithmetic warning
  uml/x86: use x86 load_unaligned_zeropad()
  asm/user.h: killed unused macros
  constify struct path argument of finish_automount()/do_add_mount()
  fs: Remove FIXME comment in generic_write_checks()
2022-04-01 19:57:03 -07:00
Linus Torvalds
e8b767f5e0 Merge tag 'for-linus-5.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml
Pull UML updates from Richard Weinberger:

 - Devicetree support (for testing)

 - Various cleanups and fixes: UBD, port_user, uml_mconsole

 - Maintainer update

* tag 'for-linus-5.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml:
  um: run_helper: Write error message to kernel log on exec failure on host
  um: port_user: Improve error handling when port-helper is not found
  um: port_user: Allow setting path to port-helper using UML_PORT_HELPER envvar
  um: port_user: Search for in.telnetd in PATH
  um: clang: Strip out -mno-global-merge from USER_CFLAGS
  docs: UML: Mention telnetd for port channel
  um: Remove unused timeval_to_ns() function
  um: Fix uml_mconsole stop/go
  um: Cleanup syscall_handler_t definition/cast, fix warning
  uml: net: vector: fix const issue
  um: Fix WRITE_ZEROES in the UBD Driver
  um: Migrate vector drivers to NAPI
  um: Fix order of dtb unflatten/early init
  um: fix and optimize xor select template for CONFIG64 and timetravel mode
  um: Document dtb command line option
  lib/logic_iomem: correct fallback config references
  um: Remove duplicated include in syscalls_64.c
  MAINTAINERS: Update UserModeLinux entry
2022-03-31 16:16:58 -07:00
Linus Torvalds
d0858cbdef Merge tag 'overflow-v5.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux
Pull overflow updates from Kees Cook:
 "These changes come in roughly two halves: support of Gustavo A. R.
  Silva's struct_size() work via additional helpers for catching
  overflow allocation size calculations, and conversions of selftests to
  KUnit (which includes some tweaks for UML + Clang):

   - Convert overflow selftest to KUnit

   - Convert stackinit selftest to KUnit

   - Implement size_t saturating arithmetic helpers

   - Allow struct_size() to be used in initializers"

* tag 'overflow-v5.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
  lib: stackinit: Convert to KUnit
  um: Allow builds with Clang
  lib: overflow: Convert to Kunit
  overflow: Provide constant expression struct_size
  overflow: Implement size_t saturating arithmetic helpers
  test_overflow: Regularize test reporting output
2022-03-21 19:46:41 -07:00
Kees Cook
c7500c1b53 um: Allow builds with Clang
Add SUBARCH target for Clang+um (which must go last, not alphabetically,
so the other SUBARCHes are assigned). Remove open-coded "DEFINE"
macro, instead using linux/kbuild.h's version which was updated to use
Clang-friendly assembly in commit cf0c3e68aa ("kbuild: fix asm-offset
generation to work with clang"). Redefine "DEFINE_LONGS" in terms of
"COMMENT" and "DEFINE" so that the intended coment actually has useful
content. Add a missed "break" to avoid implicit fall-through warnings.

This lets me run KUnit tests with Clang:

$ ./tools/testing/kunit/kunit.py run --make_options LLVM=1
...

Cc: Jeff Dike <jdike@addtoit.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: David Gow <davidgow@google.com>
Cc: linux-um@lists.infradead.org
Cc: linux-kbuild@vger.kernel.org
Cc: linux-kselftest@vger.kernel.org
Cc: kunit-dev@googlegroups.com
Cc: llvm@lists.linux.dev
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Link: https://lore.kernel.org/lkml/Yg2YubZxvYvx7%2Fnm@dev-arch.archlinux-ax161/
Tested-by: David Gow <davidgow@google.com>
Link: https://lore.kernel.org/lkml/CABVgOSk=oFxsbSbQE-v65VwR2+mXeGXDDjzq8t7FShwjJ3+kUg@mail.gmail.com/
Signed-off-by: Kees Cook <keescook@chromium.org>
---
v1: https://lore.kernel.org/lkml/20220217002843.2312603-1-keescook@chromium.org
v2: https://lore.kernel.org/lkml/20220224055831.1854786-1-keescook@chromium.org
v3:
 - use kbuild.h to avoid duplication (Masahiro)
 - fix intended comments (Masahiro)
 - use SUBARCH (Nathan)
2022-03-21 08:13:03 -07:00
David Gow
f4f03f299a um: Cleanup syscall_handler_t definition/cast, fix warning
The syscall_handler_t type for x86_64 was defined as 'long (*)(void)',
but always cast to 'long (*)(long, long, long, long, long, long)' before
use. This now triggers a warning (see below).

Define syscall_handler_t as the latter instead, and remove the cast.
This simplifies the code, and fixes the warning.

Warning:
In file included from ../arch/um/include/asm/processor-generic.h:13
                 from ../arch/x86/um/asm/processor.h:41
                 from ../include/linux/rcupdate.h:30
                 from ../include/linux/rculist.h:11
                 from ../include/linux/pid.h:5
                 from ../include/linux/sched.h:14
                 from ../include/linux/ptrace.h:6
                 from ../arch/um/kernel/skas/syscall.c:7:
../arch/um/kernel/skas/syscall.c: In function ‘handle_syscall’:
../arch/x86/um/shared/sysdep/syscalls_64.h:18:11: warning: cast between incompatible function types from ‘long int (*)(void)’ to ‘long int (*)(long int,  long int,  long int,  long int,  long int,  long int)’ [
-Wcast-function-type]
   18 |         (((long (*)(long, long, long, long, long, long)) \
      |           ^
../arch/x86/um/asm/ptrace.h:36:62: note: in definition of macro ‘PT_REGS_SET_SYSCALL_RETURN’
   36 | #define PT_REGS_SET_SYSCALL_RETURN(r, res) (PT_REGS_AX(r) = (res))
      |                                                              ^~~
../arch/um/kernel/skas/syscall.c:46:33: note: in expansion of macro ‘EXECUTE_SYSCALL’
   46 |                                 EXECUTE_SYSCALL(syscall, regs));
      |                                 ^~~~~~~~~~~~~~~

Signed-off-by: David Gow <davidgow@google.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2022-03-11 10:48:03 +01:00
Yang Li
3bdd271bc8 um: Remove duplicated include in syscalls_64.c
Fix following includecheck warning:
./arch/x86/um/syscalls_64.c: registers.h is included more than once.

Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Fixes: dbba7f704a ("um: stop polluting the namespace with registers.h contents")
Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2022-03-11 10:41:08 +01:00
Catalin Marinas
b62a8486de elfcore: Replace CONFIG_{IA64, UML} checks with a new option
As arm64 is about to introduce MTE-specific phdrs in the core dump, add
a common CONFIG_ARCH_BINFMT_ELF_EXTRA_PHDRS option currently selectable
by UML_X86 and IA64.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Link: https://lore.kernel.org/r/20220131165456.2160675-2-catalin.marinas@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
2022-02-15 22:53:28 +00:00
Al Viro
6692531df6 uml/x86: use x86 load_unaligned_zeropad()
allows, among other things, to drop !DCACHE_WORD_ACCESS mess in
x86 csum-partial_64.c

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2022-01-30 21:26:39 -05:00
Linus Torvalds
3689f9f8b0 Merge tag 'bitmap-5.17-rc1' of git://github.com/norov/linux
Pull bitmap updates from Yury Norov:

 - introduce for_each_set_bitrange()

 - use find_first_*_bit() instead of find_next_*_bit() where possible

 - unify for_each_bit() macros

* tag 'bitmap-5.17-rc1' of git://github.com/norov/linux:
  vsprintf: rework bitmap_list_string
  lib: bitmap: add performance test for bitmap_print_to_pagebuf
  bitmap: unify find_bit operations
  mm/percpu: micro-optimize pcpu_is_populated()
  Replace for_each_*_bit_from() with for_each_*_bit() where appropriate
  find: micro-optimize for_each_{set,clear}_bit()
  include/linux: move for_each_bit() macros from bitops.h to find.h
  cpumask: replace cpumask_next_* with cpumask_first_* where appropriate
  tools: sync tools/bitmap with mother linux
  all: replace find_next{,_zero}_bit with find_first{,_zero}_bit where appropriate
  cpumask: use find_first_and_bit()
  lib: add find_first_and_bit()
  arch: remove GENERIC_FIND_FIRST_BIT entirely
  include: move find.h from asm_generic to linux
  bitops: move find_bit_*_le functions from le.h to find.h
  bitops: protect find_first_{,zero}_bit properly
2022-01-23 06:20:44 +02:00
Yury Norov
c126a53c27 arch: remove GENERIC_FIND_FIRST_BIT entirely
In 5.12 cycle we enabled GENERIC_FIND_FIRST_BIT config option for ARM64
and MIPS. It increased performance and shrunk .text size; and so far
I didn't receive any negative feedback on the change.

https://lore.kernel.org/linux-arch/20210225135700.1381396-1-yury.norov@gmail.com/

Now I think it's a good time to switch all architectures to use
find_{first,last}_bit() unconditionally, and so remove corresponding
config option.

The patch does't introduce functioal changes for arc, arm, arm64, mips,
m68k, s390 and x86, for other architectures I expect improvement both in
performance and .text size.

Signed-off-by: Yury Norov <yury.norov@gmail.com>
Tested-by: Alexander Lobakin <alobakin@pm.me> (mips)
Reviewed-by: Alexander Lobakin <alobakin@pm.me> (mips)
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Will Deacon <will@kernel.org>
Tested-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
2022-01-15 08:47:31 -08:00
Linus Torvalds
64ad946152 Merge tag 'x86_core_for_v5.17_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 core updates from Borislav Petkov:

 - Get rid of all the .fixup sections because this generates
   misleading/wrong stacktraces and confuse RELIABLE_STACKTRACE and
   LIVEPATCH as the backtrace misses the function which is being fixed
   up.

 - Add Straight Line Speculation mitigation support which uses a new
   compiler switch -mharden-sls= which sticks an INT3 after a RET or an
   indirect branch in order to block speculation after them. Reportedly,
   CPUs do speculate behind such insns.

 - The usual set of cleanups and improvements

* tag 'x86_core_for_v5.17_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (32 commits)
  x86/entry_32: Fix segment exceptions
  objtool: Remove .fixup handling
  x86: Remove .fixup section
  x86/word-at-a-time: Remove .fixup usage
  x86/usercopy: Remove .fixup usage
  x86/usercopy_32: Simplify __copy_user_intel_nocache()
  x86/sgx: Remove .fixup usage
  x86/checksum_32: Remove .fixup usage
  x86/vmx: Remove .fixup usage
  x86/kvm: Remove .fixup usage
  x86/segment: Remove .fixup usage
  x86/fpu: Remove .fixup usage
  x86/xen: Remove .fixup usage
  x86/uaccess: Remove .fixup usage
  x86/futex: Remove .fixup usage
  x86/msr: Remove .fixup usage
  x86/extable: Extend extable functionality
  x86/entry_32: Remove .fixup usage
  x86/entry_64: Remove .fixup usage
  x86/copy_mc_64: Remove .fixup usage
  ...
2022-01-12 16:31:19 -08:00
Christoph Hellwig
8bb227ac34 um: remove set_fs
Remove address space overrides using set_fs() for User Mode Linux.
Note that just like the existing kernel access case of the uaccess
routines the new nofault kernel handlers do not actually have any
exception handling.  This is probably broken, but not change to the
status quo.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Richard Weinberger <richard@nod.at>
2021-12-22 17:56:56 +01:00
Al Viro
2098e213dd uml/i386: missing include in barrier.h
we need cpufeatures.h there

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>
2021-12-21 21:31:35 +01:00
Al Viro
dbba7f704a um: stop polluting the namespace with registers.h contents
Only one extern in there is needed in processor-generic.h, and it's
not needed anywhere else.  So move it over there and get rid of
the include in processor-generic.h, adding includes of registers.h
to the few files that need the declarations in it.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>
2021-12-21 21:31:35 +01:00
Al Viro
577ade59b9 um: move amd64 variant of mmap(2) to arch/x86/um/syscalls_64.c
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>
2021-12-21 21:30:44 +01:00
Al Viro
8f5c84f367 uml: trim unused junk from arch/x86/um/sys_call_table_*.c
a bunch of detritus there - definitions that are never expanded or
checked.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>
2021-12-21 21:30:44 +01:00
Randy Dunlap
077b732094 um: registers: Rename function names to avoid conflicts and build problems
The function names init_registers() and restore_registers() are used
in several net/ethernet/ and gpu/drm/ drivers for other purposes (not
calls to UML functions), so rename them.

This fixes multiple build errors.

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Cc: linux-um@lists.infradead.org
Signed-off-by: Richard Weinberger <richard@nod.at>
2021-12-21 21:22:19 +01:00
Johannes Berg
494545aa9b uml: x86: add FORCE to user_constants.h
The build system has started warning when filechk is called
without FORCE:

arch/x86/um/Makefile:44: FORCE prerequisite is missing

Add FORCE to make sure the file is checked/rebuilt when
necessary (and to quiet up the warning.)

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Reviewed-by: David Gow <davidgow@google.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2021-12-21 21:13:44 +01:00
Peter Zijlstra
f94909ceb1 x86: Prepare asm files for straight-line-speculation
Replace all ret/retq instructions with RET in preparation of making
RET a macro. Since AS is case insensitive it's a big no-op without
RET defined.

  find arch/x86/ -name \*.S | while read file
  do
	sed -i 's/\<ret[q]*\>/RET/' $file
  done

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lore.kernel.org/r/20211204134907.905503893@infradead.org
2021-12-08 12:25:37 +01:00
Johannes Berg
adf9ae0d15 um: fix stub location calculation
In commit 9f0b4807a4 ("um: rework userspace stubs to not hard-code
stub location") I changed stub_segv_handler() to do a calculation with
a pointer to a stack variable to find the data page that we're using
for the stack and the rest of the data. This same commit was meant to
do it as well for stub_clone_handler(), but the change inadvertently
went into commit 84b2789d61 ("um: separate child and parent errors
in clone stub") instead.

This was reported to not be compiled correctly by gcc 5, causing the
code to crash here. I'm not sure why, perhaps it's UB because the var
isn't initialized? In any case, this trick always seemed bad, so just
create a new inline function that does the calculation in assembly.

Reported-by: subashab@codeaurora.org
Fixes: 9f0b4807a4 ("um: rework userspace stubs to not hard-code stub location")
Fixes: 84b2789d61 ("um: separate child and parent errors in clone stub")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2021-08-26 22:28:03 +02:00
Brian Gerst
d48ca5b98f x86/uml/syscalls: Remove array index from syscall initializers
The recent syscall table generator rework removed the index from the
initializers for native x86 syscall tables, but missed the UML syscall
tables.

Fixes: 44fe4895f4 ("Stop filling syscall arrays with *_sys_ni_syscall")
Signed-off-by: Brian Gerst <brgerst@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Masahiro Yamada <masahiroy@kernel.org>
Link: https://lore.kernel.org/r/20210524181707.132844-2-brgerst@gmail.com
2021-05-25 16:59:23 +02:00
Masahiro Yamada
44fe4895f4 x86/syscalls: Stop filling syscall arrays with *_sys_ni_syscall
This is a follow-up cleanup after switching to the generic syscalltbl.sh.

The old x86 specific script skipped non-existing syscalls. So, the
generated syscalls_64.h, for example, had a big hole in the syscall numbers
335-423 range. That is why there exists [0 ... __NR_*_syscall_max] =
&__*_sys_ni_cyscall.

The new script, scripts/syscalltbl.sh automatically fills holes
with __SYSCALL(<nr>, sys_ni_syscall), hence such ugly code can
go away. The designated initializers, '[nr] =' are also unneeded.

Also, there is no need to give __NR_*_syscall_max+1 because the array
size is implied by the number of syscalls in the generated headers.
Hence, there is no need to include <asm/unistd.h>, either.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20210517073815.97426-4-masahiroy@kernel.org
2021-05-20 15:03:59 +02:00
Masahiro Yamada
6218d0f6b8 x86/syscalls: Switch to generic syscalltbl.sh
Many architectures duplicate similar shell scripts.

Convert x86 and UML to use scripts/syscalltbl.sh. The generic script
generates seperate headers for x86/64 and x86/x32 syscalls, while the x86
specific script coalesced them into one. Adjust the code accordingly.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20210517073815.97426-3-masahiroy@kernel.org
2021-05-20 15:03:58 +02:00
Randy Dunlap
1a594f0afa um: elf.h: Fix W=1 warning for empty body in 'do' statement
Use the common kernel style to eliminate a warning:

./arch/x86/um/asm/elf.h:215:32: warning: suggest braces around empty body in ‘do’ statement [-Wempty-body]
 #define SET_PERSONALITY(ex) do ; while(0)
                                ^

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Cc: linux-um@lists.infradead.org
Signed-off-by: Richard Weinberger <richard@nod.at>
2021-04-15 23:10:50 +02:00
Randy Dunlap
a730af6e31 um: Add 2 missing libs to fix various build errors
Fix many build errors (at least 18 build error reports) for uml on i386
by adding 2 more library object files. All missing symbols are
either cmpxchg8b_emu or atomic*386.

Here are a few examples of the build errors that are eliminated:

   /usr/bin/ld: core.c:(.text+0xd83): undefined reference to `cmpxchg8b_emu'
   /usr/bin/ld: core.c:(.text+0x2bb2): undefined reference to `atomic64_add_386'
   /usr/bin/ld: core.c:(.text+0x2c5d): undefined reference to `atomic64_xchg_386'
   syscall.c:(.text+0x2f49): undefined reference to `atomic64_set_386'
   /usr/bin/ld: syscall.c:(.text+0x2f54): undefined reference to `atomic64_set_386'
   syscall.c:(.text+0x33a4): undefined reference to `atomic64_inc_386'
   /usr/bin/ld: syscall.c:(.text+0x33ac): undefined reference to `atomic64_inc_386'
   /usr/bin/ld: net/ipv4/inet_timewait_sock.o: in function `inet_twsk_alloc':
   inet_timewait_sock.c:(.text+0x3d1): undefined reference to `atomic64_read_386'
   /usr/bin/ld: inet_timewait_sock.c:(.text+0x3dd): undefined reference to `atomic64_set_386'
   /usr/bin/ld: net/ipv4/inet_connection_sock.o: in function `inet_csk_clone_lock':
   inet_connection_sock.c:(.text+0x1d74): undefined reference to `atomic64_read_386'
   /usr/bin/ld: inet_connection_sock.c:(.text+0x1d80): undefined reference to `atomic64_set_386'
   /usr/bin/ld: net/ipv4/tcp_input.o: in function `inet_reqsk_alloc':
   tcp_input.c:(.text+0xa345): undefined reference to `atomic64_set_386'
   /usr/bin/ld: net/mac80211/wpa.o: in function `ieee80211_crypto_tkip_encrypt':
   wpa.c:(.text+0x739): undefined reference to `atomic64_inc_return_386'

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Reported-by: kernel test robot <lkp@intel.com>
Cc: Brendan Jackman <jackmanb@google.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: kbuild-all@lists.01.org
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Cc: linux-um@lists.infradead.org
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2021-04-15 23:10:40 +02:00
Johannes Berg
dc01a3b9db um: Fix tag order in stub_32.h
"static void inline" is the wrong way around, fix that.

Reported-by: kernel test robot <lkp@intel.com>
Fixes: 9f0b4807a4 ("um: rework userspace stubs to not hard-code stub location")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2021-04-15 23:06:37 +02:00
Johannes Berg
bfc58e2b98 um: remove process stub VMA
This mostly reverts the old commit 3963333fe6 ("uml: cover stubs
with a VMA") which had added a VMA to the existing PTEs. However,
there's no real reason to have the PTEs in the first place and the
VMA cannot be 'fixed' in place, which leads to bugs that userspace
could try to unmap them and be forcefully killed, or such. Also,
there's a bit of an ugly hole in userspace's address space.

Simplify all this: just install the stub code/page at the top of
the (inner) address space, i.e. put it just above TASK_SIZE. The
pages are simply hard-coded to be mapped in the userspace process
we use to implement an mm context, and they're out of reach of the
inner mmap/munmap/mprotect etc. since they're above TASK_SIZE.

Getting rid of the VMA also makes vma_merge() no longer hit one of
the VM_WARN_ON()s there because we installed a VMA while the code
assumes the stack VMA is the first one.

It also removes a lockdep warning about mmap_sem usage since we no
longer have uml_setup_stubs() and thus no longer need to do any
manipulation that would require mmap_sem in activate_mm().

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2021-02-12 21:37:38 +01:00
Johannes Berg
9f0b4807a4 um: rework userspace stubs to not hard-code stub location
The userspace stacks mostly have a stack (and in the case of the
syscall stub we can just set their stack pointer) that points to
the location of the stub data page already.

Rework the stubs to use the stack pointer to derive the start of
the data page, rather than requiring it to be hard-coded.

In the clone stub, also integrate the int3 into the stack remap,
since we really must not use the stack while we remap it.

This prepares for putting the stub at a variable location that's
not part of the normal address space of the userspace processes
running inside the UML machine.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2021-02-12 21:35:02 +01:00
Johannes Berg
84b2789d61 um: separate child and parent errors in clone stub
If the two are mixed up, then it looks as though the parent
returned an error if the child failed (before) the mmap(),
and then the resulting process never gets killed. Fix this
by splitting the child and parent errors, reporting and
using them appropriately.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2021-02-12 21:34:33 +01:00
Linus Torvalds
bf9a76a470 arch/um: partially revert the conversion to __section() macro
A couple of um files ended up not including the header file that defines
the __section() macro, and the simplest fix is to just revert the change
for those files.

Fixes: 33def8498f treewide: Convert macro and uses of __section(foo) to __section("foo")
Reported-and-tested-by: Guenter Roeck <linux@roeck-us.net>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-26 15:39:37 -07:00
Joe Perches
33def8498f treewide: Convert macro and uses of __section(foo) to __section("foo")
Use a more generic form for __section that requires quotes to avoid
complications with clang and gcc differences.

Remove the quote operator # from compiler_attributes.h __section macro.

Convert all unquoted __section(foo) uses to quoted __section("foo").
Also convert __attribute__((section("foo"))) uses to __section("foo")
even if the __attribute__ has multiple list entry forms.

Conversion done using the script at:

    https://lore.kernel.org/lkml/75393e5ddc272dc7403de74d645e6c6e0f4e70eb.camel@perches.com/2-convert_section.pl

Signed-off-by: Joe Perches <joe@perches.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@gooogle.com>
Reviewed-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-25 14:51:49 -07:00
Linus Torvalds
9453b2d469 Merge tag 'for-linus-5.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml
Pull UML updates from Richard Weinberger:

 - Improve support for non-glibc systems

 - Vector: Add support for scripting and dynamic tap devices

 - Various fixes for the vector networking driver

 - Various fixes for time travel mode

* tag 'for-linus-5.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml:
  um: vector: Add dynamic tap interfaces and scripting
  um: Clean up stacktrace dump
  um: Fix incorrect assumptions about max pid length
  um: Remove dead usage of TIF_IA32
  um: Remove redundant NULL check
  um: change sigio_spinlock to a mutex
  um: time-travel: Return the sequence number in ACK messages
  um: time-travel: Fix IRQ handling in time_travel_handle_message()
  um: Allow static linking for non-glibc implementations
  um: Some fixes to build UML with musl
  um: vector: Use GFP_ATOMIC under spin lock
  um: Fix null pointer dereference in vector_user_bpf
2020-10-18 10:03:23 -07:00
Gabriel Krisman Bertazi
4687615d2d um: Remove dead usage of TIF_IA32
This seems like a dead artifact since TIF_IA32 is not even defined as a
TI flag for UM.  Looking back in git history, it made sense in the old
days, but it is apparently not used since UM was split out of the x86
arch/.  It is also going away from the x86 tree soon.

Also, I think the variable clean up it performs is not needed as 64-bit
UML doesn't run 32-bit binaries as far as I can tell, and 32-bit UML
has 32-bit ulong.

Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2020-10-11 23:19:36 +02:00
Ignat Korchagin
5e1121cd43 um: Some fixes to build UML with musl
musl toolchain and headers are a bit more strict. These fixes enable building
UML with musl as well as seem not to break on glibc.

Signed-off-by: Ignat Korchagin <ignat@cloudflare.com>
Tested-by: Brendan Higgins <brendanhiggins@google.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2020-10-11 23:13:06 +02:00
Al Viro
c693cc4676 saner calling conventions for csum_and_copy_..._user()
All callers of these primitives will
	* discard anything we might've copied in case of error
	* ignore the csum value in case of error
	* always pass 0xffffffff as the initial sum, so the
resulting csum value (in case of success, that is) will never be 0.

That suggest the following calling conventions:
	* don't pass err_ptr - just return 0 on error.
	* don't bother with zeroing destination, etc. in case of error
	* don't pass the initial sum - just use 0xffffffff.

This commit does the minimal conversion in the instances of csum_and_copy_...();
the changes of actual asm code behind them are done later in the series.
Note that this asm code is often shared with csum_partial_copy_nocheck();
the difference is that csum_partial_copy_nocheck() passes 0 for initial
sum while csum_and_copy_..._user() pass 0xffffffff.  Fortunately, we are
free to pass 0xffffffff in all cases and subsequent patches will use that
freedom without any special comments.

A part that could be split off: parisc and uml/i386 claimed to have
csum_and_copy_to_user() instances of their own, but those were identical
to the generic one, so we simply drop them.  Not sure if it's worth
a separate commit...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-08-20 15:45:15 -04:00
Al Viro
6e41c585e3 unify generic instances of csum_partial_copy_nocheck()
quite a few architectures have the same csum_partial_copy_nocheck() -
simply memcpy() the data and then return the csum of the copy.

hexagon, parisc, ia64, s390, um: explicitly spelled out that way.

arc, arm64, csky, h8300, m68k/nommu, microblaze, mips/GENERIC_CSUM, nds32,
nios2, openrisc, riscv, unicore32: end up picking the same thing spelled
out in lib/checksum.h (with varying amounts of perversions along the way).

everybody else (alpha, arm, c6x, m68k/mmu, mips/!GENERIC_CSUM, powerpc,
sh, sparc, x86, xtensa) have non-generic variants.  For all except c6x
the declaration is in their asm/checksum.h.  c6x uses the wrapper
from asm-generic/checksum.h that would normally lead to the lib/checksum.h
instance, but in case of c6x we end up using an asm function from arch/c6x
instead.

Screw that mess - have architectures with private instances define
_HAVE_ARCH_CSUM_AND_COPY in their asm/checksum.h and have the default
one right in net/checksum.h conditional on _HAVE_ARCH_CSUM_AND_COPY
*not* defined.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-08-20 15:45:14 -04:00
Masahiro Yamada
893ab00439 kbuild: remove cc-option test of -fno-stack-protector
Some Makefiles already pass -fno-stack-protector unconditionally.
For example, arch/arm64/kernel/vdso/Makefile, arch/x86/xen/Makefile.

No problem report so far about hard-coding this option. So, we can
assume all supported compilers know -fno-stack-protector.

GCC 4.8 and Clang support this option (https://godbolt.org/z/_HDGzN)

Get rid of cc-option from -fno-stack-protector.

Remove CONFIG_CC_HAS_STACKPROTECTOR_NONE, which is always 'y'.

Note:
arch/mips/vdso/Makefile adds -fno-stack-protector twice, first
unconditionally, and second conditionally. I removed the second one.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
2020-07-07 11:13:10 +09:00
Michel Lespinasse
d8ed45c5dc mmap locking API: use coccinelle to convert mmap_sem rwsem call sites
This change converts the existing mmap_sem rwsem calls to use the new mmap
locking API instead.

The change is generated using coccinelle with the following rule:

// spatch --sp-file mmap_lock_api.cocci --in-place --include-headers --dir .

@@
expression mm;
@@
(
-init_rwsem
+mmap_init_lock
|
-down_write
+mmap_write_lock
|
-down_write_killable
+mmap_write_lock_killable
|
-down_write_trylock
+mmap_write_trylock
|
-up_write
+mmap_write_unlock
|
-downgrade_write
+mmap_write_downgrade
|
-down_read
+mmap_read_lock
|
-down_read_killable
+mmap_read_lock_killable
|
-down_read_trylock
+mmap_read_trylock
|
-up_read
+mmap_read_unlock
)
-(&mm->mmap_sem)
+(mm)

Signed-off-by: Michel Lespinasse <walken@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Reviewed-by: Laurent Dufour <ldufour@linux.ibm.com>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: David Rientjes <rientjes@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Liam Howlett <Liam.Howlett@oracle.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ying Han <yinghan@google.com>
Link: http://lkml.kernel.org/r/20200520052908.204642-5-walken@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09 09:39:14 -07:00
Al Viro
5904122c46 take the dummy csum_and_copy_from_user() into net/checksum.h
now that can be done conveniently - all non-trivial cases have
_HAVE_ARCH_COPY_AND_CSUM_FROM_USER defined, so the fallback in
net/checksum.h is used only for dummy (copy_from_user, then
csum_partial) implementation.  Allowing us to get rid of all
dummy instances, both of csum_and_copy_from_user() and
csum_partial_copy_from_user().

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-05-29 16:11:50 -04:00
Anshuman Khandual
c62da0c35d mm/vma: define a default value for VM_DATA_DEFAULT_FLAGS
There are many platforms with exact same value for VM_DATA_DEFAULT_FLAGS
This creates a default value for VM_DATA_DEFAULT_FLAGS in line with the
existing VM_STACK_DEFAULT_FLAGS.  While here, also define some more
macros with standard VMA access flag combinations that are used
frequently across many platforms.  Apart from simplification, this
reduces code duplication as well.

Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Guo Ren <guoren@kernel.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Brian Cain <bcain@codeaurora.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paulburton@kernel.org>
Cc: Nick Hu <nickhu@andestech.com>
Cc: Ley Foon Tan <ley.foon.tan@intel.com>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Rich Felker <dalias@libc.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Chris Zankel <chris@zankel.net>
Link: http://lkml.kernel.org/r/1583391014-8170-2-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-10 15:36:21 -07:00
Linus Torvalds
762a9f2f01 Merge tag 'for-linus-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml
Pull UML updates from Richard Weinberger:

 - New mode for time travel, external via virtio

 - Fixes for ubd to make sure no requests can get lost

 - Fixes for vector networking

 - Allow CONFIG_STATIC_LINK only when possible

 - Minor cleanups and fixes

* tag 'for-linus-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml:
  um: Remove some unnecessary NULL checks in vector_user.c
  um: vector: Avoid NULL ptr deference if transport is unset
  um: Make CONFIG_STATIC_LINK actually static
  um: Implement cpu_relax() as ndelay(1) for time-travel
  um: Implement ndelay/udelay in time-travel mode
  um: Implement time-travel=ext
  um: virtio: Implement VHOST_USER_PROTOCOL_F_INBAND_NOTIFICATIONS
  um: time-travel: Rewrite as an event scheduler
  um: Move timer-internal.h to non-shared
  hostfs: Use kasprintf() instead of fixed buffer formatting
  um: falloc.h needs to be directly included for older libc
  um: ubd: Retry buffer read on any kind of error
  um: ubd: Prevent buffer overrun on command completion
  um: Fix overlapping ELF segments when statically linked
  um: Delete never executed timer
  um: Don't overwrite ethtool driver version
  um: Fix len of file in create_pid_file
  um: Don't use console_drivers directly
  um: Cleanup CONFIG_IOSCHED_CFQ
2020-04-07 12:36:09 -07:00
Linus Torvalds
ff2ae607c6 Merge tag 'spdx-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/spdx
Pull SPDX updates from Greg KH:
 "Here are three SPDX patches for 5.7-rc1.

  One fixes up the SPDX tag for a single driver, while the other two go
  through the tree and add SPDX tags for all of the .gitignore files as
  needed.

  Nothing too complex, but you will get a merge conflict with your
  current tree, that should be trivial to handle (one file modified by
  two things, one file deleted.)

  All three of these have been in linux-next for a while, with no
  reported issues other than the merge conflict"

* tag 'spdx-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/spdx:
  ASoC: MT6660: make spdxcheck.py happy
  .gitignore: add SPDX License Identifier
  .gitignore: remove too obvious comments
2020-04-03 13:12:26 -07:00
Linus Torvalds
5b67fbfc32 Merge tag 'kbuild-v5.7' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Pull Kbuild updates from Masahiro Yamada:
 "Build system:

   - add CONFIG_UNUSED_KSYMS_WHITELIST, which will be useful to define a
     fixed set of export symbols for Generic Kernel Image (GKI)

   - allow to run 'make dt_binding_check' without .config

   - use full schema for checking DT examples in *.yaml files

   - make modpost fail for missing MODULE_IMPORT_NS(), which makes more
     sense because we know the produced modules are never loadable

   - Remove unused 'AS' variable

  Kconfig:

   - sanitize DEFCONFIG_LIST, and remove ARCH_DEFCONFIG from Kconfig
     files

   - relax the 'imply' behavior so that symbols implied by 'y' can
     become 'm'

   - make 'imply' obey 'depends on' in order to make 'imply' really weak

  Misc:

   - add documentation on building the kernel with Clang/LLVM

   - revive __HAVE_ARCH_STRLEN for 32bit sparc to use optimized strlen()

   - fix warning from deb-pkg builds when CONFIG_DEBUG_INFO=n

   - various script and Makefile cleanups"

* tag 'kbuild-v5.7' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (34 commits)
  Makefile: Update kselftest help information
  kbuild: deb-pkg: fix warning when CONFIG_DEBUG_INFO is unset
  kbuild: add outputmakefile to no-dot-config-targets
  kbuild: remove AS variable
  net: wan: wanxl: refactor the firmware rebuild rule
  net: wan: wanxl: use $(M68KCC) instead of $(M68KAS) for rebuilding firmware
  net: wan: wanxl: use allow to pass CROSS_COMPILE_M68k for rebuilding firmware
  kbuild: add comment about grouped target
  kbuild: add -Wall to KBUILD_HOSTCXXFLAGS
  kconfig: remove unused variable in qconf.cc
  sparc: revive __HAVE_ARCH_STRLEN for 32bit sparc
  kbuild: refactor Makefile.dtbinst more
  kbuild: compute the dtbs_install destination more simply
  Makefile: disallow data races on gcc-10 as well
  kconfig: make 'imply' obey the direct dependency
  kconfig: allow symbols implied by y to become m
  net: drop_monitor: use IS_REACHABLE() to guard net_dm_hw_report()
  modpost: return error if module is missing ns imports and MODULE_ALLOW_MISSING_NAMESPACE_IMPORTS=n
  modpost: rework and consolidate logging interface
  kbuild: allow to run dt_binding_check without kernel configuration
  ...
2020-03-31 16:03:39 -07:00
Johannes Berg
5bef0a153b um: Implement cpu_relax() as ndelay(1) for time-travel
In time-travel mode, cpu_relax() currently does actual CPU relax,
but that doesn't affect the simulation. Ideally, we wouldn't run
anything that uses it in simulation, but if we actually have virtio
devices combined with the same simulation it's possible. Implement
cpu_relax() as ndelay(1) in this case, using time_travel_ndelay(1)
directly to catch errors if this is used erroneously in builds that
don't set CONFIG_UML_TIME_TRAVEL_SUPPORT.

While at it, convert it to an __always_inline and also add that to
rep_nop() like the original does now.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2020-03-29 23:29:56 +02:00
Masahiro Yamada
d198b34f38 .gitignore: add SPDX License Identifier
Add SPDX License Identifier to all .gitignore files.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-25 11:50:48 +01:00
Brian Gerst
121b32a58a x86/entry/32: Use IA32-specific wrappers for syscalls taking 64-bit arguments
For the 32-bit syscall interface, 64-bit arguments (loff_t) are passed via
a pair of 32-bit registers.  These register pairs end up in consecutive stack
slots, which matches the C ABI for 64-bit arguments.  But when accessing the
registers directly from pt_regs, the wrapper needs to manually reassemble the
64-bit value.  These wrappers already exist for 32-bit compat, so make them
available to 32-bit native in preparation for enabling pt_regs-based syscalls.

Signed-off-by: Brian Gerst <brgerst@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Link: https://lkml.kernel.org/r/20200313195144.164260-16-brgerst@gmail.com
2020-03-21 16:03:24 +01:00
Brian Gerst
8210efcb15 x86/entry/64: Add __SYSCALL_COMMON()
Add a __SYSCALL_COMMON() macro to the syscall table, which simplifies syscalltbl.sh.

Signed-off-by: Brian Gerst <brgerst@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200313195144.164260-12-brgerst@gmail.com
2020-03-21 16:03:22 +01:00
Brian Gerst
b5592e5c0d x86/entry: Remove syscall qualifier support
Syscall qualifier support is no longer needed.

Signed-off-by: Brian Gerst <brgerst@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Link: https://lkml.kernel.org/r/20200313195144.164260-11-brgerst@gmail.com
2020-03-21 16:03:22 +01:00
Brian Gerst
0872098804 x86/entry: Move max syscall number calculation to syscallhdr.sh
Instead of using an array in asm-offsets to calculate the max syscall
number, calculate it when writing out the syscall headers.

Signed-off-by: Brian Gerst <brgerst@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200313195144.164260-9-brgerst@gmail.com
2020-03-21 16:03:21 +01:00