Commit Graph

40406 Commits

Author SHA1 Message Date
Krish Sadhukhan
174a921b69 nSVM: Check for reserved encodings of TLB_CONTROL in nested VMCB
According to section "TLB Flush" in APM vol 2,

    "Support for TLB_CONTROL commands other than the first two, is
     optional and is indicated by CPUID Fn8000_000A_EDX[FlushByAsid].

     All encodings of TLB_CONTROL not defined in the APM are reserved."

Signed-off-by: Krish Sadhukhan <krish.sadhukhan@oracle.com>
Message-Id: <20210920235134.101970-3-krish.sadhukhan@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-10-01 03:44:57 -04:00
Juergen Gross
78b497f2e6 kvm: use kvfree() in kvm_arch_free_vm()
By switching from kfree() to kvfree() in kvm_arch_free_vm() Arm64 can
use the common variant. This can be accomplished by adding another
macro __KVM_HAVE_ARCH_VM_FREE, which will be used only by x86 for now.

Further simplification can be achieved by adding __kvm_arch_free_vm()
doing the common part.

Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Message-Id: <20210903130808.30142-5-jgross@suse.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-10-01 03:44:57 -04:00
Babu Moger
b73a54321a KVM: x86: Expose Predictive Store Forwarding Disable
Predictive Store Forwarding: AMD Zen3 processors feature a new
technology called Predictive Store Forwarding (PSF).

PSF is a hardware-based micro-architectural optimization designed
to improve the performance of code execution by predicting address
dependencies between loads and stores.

How PSF works:

It is very common for a CPU to execute a load instruction to an address
that was recently written by a store. Modern CPUs implement a technique
known as Store-To-Load-Forwarding (STLF) to improve performance in such
cases. With STLF, data from the store is forwarded directly to the load
without having to wait for it to be written to memory. In a typical CPU,
STLF occurs after the address of both the load and store are calculated
and determined to match.

PSF expands on this by speculating on the relationship between loads and
stores without waiting for the address calculation to complete. With PSF,
the CPU learns over time the relationship between loads and stores. If
STLF typically occurs between a particular store and load, the CPU will
remember this.

In typical code, PSF provides a performance benefit by speculating on
the load result and allowing later instructions to begin execution
sooner than they otherwise would be able to.

The details of security analysis of AMD predictive store forwarding is
documented here.
https://www.amd.com/system/files/documents/security-analysis-predictive-store-forwarding.pdf

Predictive Store Forwarding controls:
There are two hardware control bits which influence the PSF feature:
- MSR 48h bit 2 – Speculative Store Bypass (SSBD)
- MSR 48h bit 7 – Predictive Store Forwarding Disable (PSFD)

The PSF feature is disabled if either of these bits are set.  These bits
are controllable on a per-thread basis in an SMT system. By default, both
SSBD and PSFD are 0 meaning that the speculation features are enabled.

While the SSBD bit disables PSF and speculative store bypass, PSFD only
disables PSF.

PSFD may be desirable for software which is concerned with the
speculative behavior of PSF but desires a smaller performance impact than
setting SSBD.

Support for PSFD is indicated in CPUID Fn8000_0008 EBX[28].
All processors that support PSF will also support PSFD.

Linux kernel does not have the interface to enable/disable PSFD yet. Plan
here is to expose the PSFD technology to KVM so that the guest kernel can
make use of it if they wish to.

Signed-off-by: Babu Moger <Babu.Moger@amd.com>
Message-Id: <163244601049.30292.5855870305350227855.stgit@bmoger-ubuntu>
[Keep feature private to KVM, as requested by Borislav Petkov. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-10-01 03:44:57 -04:00
David Matlack
53597858db KVM: x86/mmu: Avoid memslot lookup in make_spte and mmu_try_to_unsync_pages
mmu_try_to_unsync_pages checks if page tracking is active for the given
gfn, which requires knowing the memslot. We can pass down the memslot
via make_spte to avoid this lookup.

The memslot is also handy for make_spte's marking of the gfn as dirty:
we can test whether dirty page tracking is enabled, and if so ensure that
pages are mapped as writable with 4K granularity.  Apart from the warning,
no functional change is intended.

Signed-off-by: David Matlack <dmatlack@google.com>
Message-Id: <20210813203504.2742757-7-dmatlack@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-10-01 03:44:56 -04:00
David Matlack
8a9f566ae4 KVM: x86/mmu: Avoid memslot lookup in rmap_add
Avoid the memslot lookup in rmap_add, by passing it down from the fault
handling code to mmu_set_spte and then to rmap_add.

No functional change intended.

Signed-off-by: David Matlack <dmatlack@google.com>
Message-Id: <20210813203504.2742757-6-dmatlack@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-10-01 03:44:56 -04:00
Paolo Bonzini
a12f43818b KVM: MMU: pass struct kvm_page_fault to mmu_set_spte
mmu_set_spte is called for either PTE prefetching or page faults.  The
three boolean arguments write_fault, speculative and host_writable are
always respectively false/true/true for prefetching and coming from
a struct kvm_page_fault for page faults.

Let mmu_set_spte distinguish these two situation by accepting a
possibly NULL struct kvm_page_fault argument.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-10-01 03:44:56 -04:00
Paolo Bonzini
7158bee4b4 KVM: MMU: pass kvm_mmu_page struct to make_spte
The level and A/D bit support of the new SPTE can be found in the role,
which is stored in the kvm_mmu_page struct.  This merges two arguments
into one.

For the TDP MMU, the kvm_mmu_page was not used (kvm_tdp_mmu_map does
not use it if the SPTE is already present) so we fetch it just before
calling make_spte.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-10-01 03:44:55 -04:00
Paolo Bonzini
87e888eafd KVM: MMU: set ad_disabled in TDP MMU role
Prepare for removing the ad_disabled argument of make_spte; instead it can
be found in the role of a struct kvm_mmu_page.  First of all, the TDP MMU
must set the role accurately.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-10-01 03:44:55 -04:00
Paolo Bonzini
eb5cd7ffe1 KVM: MMU: remove unnecessary argument to mmu_set_spte
The level of the new SPTE can be found in the kvm_mmu_page struct; there
is no need to pass it down.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-10-01 03:44:55 -04:00
Paolo Bonzini
ad67e4806e KVM: MMU: clean up make_spte return value
Now that make_spte is called directly by the shadow MMU (rather than
wrapped by set_spte), it only has to return one boolean value.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-10-01 03:44:54 -04:00
Paolo Bonzini
4758d47e0d KVM: MMU: inline set_spte in FNAME(sync_page)
Since the two callers of set_spte do different things with the results,
inlining it actually makes the code simpler to reason about.  For example,
FNAME(sync_page) already has a struct kvm_mmu_page *, but set_spte had to
fish it back out of sptep's private page data.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-10-01 03:44:54 -04:00
Paolo Bonzini
d786c7783b KVM: MMU: inline set_spte in mmu_set_spte
Since the two callers of set_spte do different things with the results,
inlining it actually makes the code simpler to reason about.  For example,
mmu_set_spte looks quite like tdp_mmu_map_handle_target_level, but the
similarity is hidden by set_spte.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-10-01 03:44:54 -04:00
David Matlack
888104138c KVM: x86/mmu: Avoid memslot lookup in page_fault_handle_page_track
Now that kvm_page_fault has a pointer to the memslot it can be passed
down to the page tracking code to avoid a redundant slot lookup.

No functional change intended.

Signed-off-by: David Matlack <dmatlack@google.com>
Message-Id: <20210813203504.2742757-5-dmatlack@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-10-01 03:44:53 -04:00
David Matlack
e710c5f6be KVM: x86/mmu: Pass the memslot around via struct kvm_page_fault
The memslot for the faulting gfn is used throughout the page fault
handling code, so capture it in kvm_page_fault as soon as we know the
gfn and use it in the page fault handling code that has direct access
to the kvm_page_fault struct.  Replace various tests using is_noslot_pfn
with more direct tests on fault->slot being NULL.

This, in combination with the subsequent patch, improves "Populate
memory time" in dirty_log_perf_test by 5% when using the legacy MMU.
There is no discerable improvement to the performance of the TDP MMU.

No functional change intended.

Suggested-by: Ben Gardon <bgardon@google.com>
Signed-off-by: David Matlack <dmatlack@google.com>
Message-Id: <20210813203504.2742757-4-dmatlack@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-10-01 03:44:53 -04:00
Paolo Bonzini
6ccf443882 KVM: MMU: unify tdp_mmu_map_set_spte_atomic and tdp_mmu_set_spte_atomic_no_dirty_log
tdp_mmu_map_set_spte_atomic is not taking care of dirty logging anymore,
the only difference that remains is that it takes a vCPU instead of
the struct kvm.  Merge the two functions.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-10-01 03:44:53 -04:00
Paolo Bonzini
bcc4f2bc50 KVM: MMU: mark page dirty in make_spte
This simplifies set_spte, which we want to remove, and unifies code
between the shadow MMU and the TDP MMU.  The warning will be added
back later to make_spte as well.

There is a small disadvantage in the TDP MMU; it may unnecessarily mark
a page as dirty twice if two vCPUs end up mapping the same page twice.
However, this is a very small cost for a case that is already rare.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-10-01 03:44:53 -04:00
David Matlack
68be1306ca KVM: x86/mmu: Fold rmap_recycle into rmap_add
Consolidate rmap_recycle and rmap_add into a single function since they
are only ever called together (and only from one place). This has a nice
side effect of eliminating an extra kvm_vcpu_gfn_to_memslot(). In
addition it makes mmu_set_spte(), which is a very long function, a
little shorter.

No functional change intended.

Signed-off-by: David Matlack <dmatlack@google.com>
Message-Id: <20210813203504.2742757-3-dmatlack@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-10-01 03:44:52 -04:00
Sean Christopherson
b1a429fb18 KVM: x86/mmu: Verify shadow walk doesn't terminate early in page faults
WARN and bail if the shadow walk for faulting in a SPTE terminates early,
i.e. doesn't reach the expected level because the walk encountered a
terminal SPTE.  The shadow walks for page faults are subtle in that they
install non-leaf SPTEs (zapping leaf SPTEs if necessary!) in the loop
body, and consume the newly created non-leaf SPTE in the loop control,
e.g. __shadow_walk_next().  In other words, the walks guarantee that the
walk will stop if and only if the target level is reached by installing
non-leaf SPTEs to guarantee the walk remains valid.

Opportunistically use fault->goal-level instead of it.level in
FNAME(fetch) to further clarify that KVM always installs the leaf SPTE at
the target level.

Reviewed-by: Lai Jiangshan <jiangshanlai@gmail.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com>
Message-Id: <20210906122547.263316-1-jiangshanlai@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-10-01 03:44:52 -04:00
Paolo Bonzini
f0066d94c9 KVM: MMU: change tracepoints arguments to kvm_page_fault
Pass struct kvm_page_fault to tracepoints instead of extracting the
arguments from the struct.  This also lets the kvm_mmu_spte_requested
tracepoint pick the gfn directly from fault->gfn, instead of using
the address.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-10-01 03:44:52 -04:00
Paolo Bonzini
536f0e6ace KVM: MMU: change disallowed_hugepage_adjust() arguments to kvm_page_fault
Pass struct kvm_page_fault to disallowed_hugepage_adjust() instead of
extracting the arguments from the struct.  Tweak a bit the conditions
to avoid long lines.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-10-01 03:44:51 -04:00
Paolo Bonzini
73a3c65947 KVM: MMU: change kvm_mmu_hugepage_adjust() arguments to kvm_page_fault
Pass struct kvm_page_fault to kvm_mmu_hugepage_adjust() instead of
extracting the arguments from the struct; the results are also stored
in the struct, so the callers are adjusted consequently.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-10-01 03:44:51 -04:00
Paolo Bonzini
3c8ad5a675 KVM: MMU: change fast_page_fault() arguments to kvm_page_fault
Pass struct kvm_page_fault to fast_page_fault() instead of
extracting the arguments from the struct.

Suggested-by: Isaku Yamahata <isaku.yamahata@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-10-01 03:44:51 -04:00
Paolo Bonzini
cdc47767a0 KVM: MMU: change tdp_mmu_map_handle_target_level() arguments to kvm_page_fault
Pass struct kvm_page_fault to tdp_mmu_map_handle_target_level() instead of
extracting the arguments from the struct.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-10-01 03:44:50 -04:00
Paolo Bonzini
2f6305dd56 KVM: MMU: change kvm_tdp_mmu_map() arguments to kvm_page_fault
Pass struct kvm_page_fault to kvm_tdp_mmu_map() instead of
extracting the arguments from the struct.

Suggested-by: Isaku Yamahata <isaku.yamahata@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-10-01 03:44:50 -04:00
Paolo Bonzini
9c03b1821a KVM: MMU: change FNAME(fetch)() arguments to kvm_page_fault
Pass struct kvm_page_fault to FNAME(fetch)() instead of
extracting the arguments from the struct.

Suggested-by: Isaku Yamahata <isaku.yamahata@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-10-01 03:44:50 -04:00
Paolo Bonzini
43b74355ef KVM: MMU: change __direct_map() arguments to kvm_page_fault
Pass struct kvm_page_fault to __direct_map() instead of
extracting the arguments from the struct.

Suggested-by: Isaku Yamahata <isaku.yamahata@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-10-01 03:44:50 -04:00
Paolo Bonzini
3a13f4fea3 KVM: MMU: change handle_abnormal_pfn() arguments to kvm_page_fault
Pass struct kvm_page_fault to handle_abnormal_pfn() instead of
extracting the arguments from the struct.

Suggested-by: Isaku Yamahata <isaku.yamahata@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-10-01 03:44:49 -04:00
Paolo Bonzini
3647cd04b7 KVM: MMU: change kvm_faultin_pfn() arguments to kvm_page_fault
Add fields to struct kvm_page_fault corresponding to outputs of
kvm_faultin_pfn().  For now they have to be extracted again from struct
kvm_page_fault in the subsequent steps, but this is temporary until
other functions in the chain are switched over as well.

Suggested-by: Isaku Yamahata <isaku.yamahata@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-10-01 03:44:49 -04:00
Paolo Bonzini
b8a5d55115 KVM: MMU: change page_fault_handle_page_track() arguments to kvm_page_fault
Add fields to struct kvm_page_fault corresponding to the arguments
of page_fault_handle_page_track().  The fields are initialized in the
callers, and page_fault_handle_page_track() receives a struct
kvm_page_fault instead of having to extract the arguments out of it.

Suggested-by: Isaku Yamahata <isaku.yamahata@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-10-01 03:44:49 -04:00
Paolo Bonzini
4326e57ef4 KVM: MMU: change direct_page_fault() arguments to kvm_page_fault
Add fields to struct kvm_page_fault corresponding to
the arguments of direct_page_fault().  The fields are
initialized in the callers, and direct_page_fault()
receives a struct kvm_page_fault instead of having to
extract the arguments out of it.

Also adjust FNAME(page_fault) to store the max_level in
struct kvm_page_fault, to keep it similar to the direct
map path.

Suggested-by: Isaku Yamahata <isaku.yamahata@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-10-01 03:44:49 -04:00
Paolo Bonzini
c501040abc KVM: MMU: change mmu->page_fault() arguments to kvm_page_fault
Pass struct kvm_page_fault to mmu->page_fault() instead of
extracting the arguments from the struct.  FNAME(page_fault) can use
the precomputed bools from the error code.

Suggested-by: Isaku Yamahata <isaku.yamahata@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-10-01 03:44:48 -04:00
Paolo Bonzini
6defd9bb17 KVM: MMU: Introduce struct kvm_page_fault
Create a single structure for arguments that are passed from
kvm_mmu_do_page_fault to the page fault handlers.  Later
the structure will grow to include various output parameters
that are passed back to the next steps in the page fault
handling.

Suggested-by: Isaku Yamahata <isaku.yamahata@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-10-01 03:44:48 -04:00
Paolo Bonzini
d055f028a5 KVM: MMU: pass unadulterated gpa to direct_page_fault
Do not bother removing the low bits of the gpa.  This masking dates back
to the very first commit of KVM but it is unnecessary, as exemplified
by the other call in kvm_tdp_page_fault.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-10-01 03:44:48 -04:00
Oliver Upton
55c0cefbdb KVM: x86: Fix potential race in KVM_GET_CLOCK
Sean noticed that KVM_GET_CLOCK was checking kvm_arch.use_master_clock
outside of the pvclock sync lock. This is problematic, as the clock
value written to the user may or may not actually correspond to a stable
TSC.

Fix the race by populating the entire kvm_clock_data structure behind
the pvclock_gtod_sync_lock.

Suggested-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Oliver Upton <oupton@google.com>
Message-Id: <20210916181538.968978-4-oupton@google.com>
Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-10-01 03:44:47 -04:00
Paolo Bonzini
45e6c2fac0 KVM: x86: extract KVM_GET_CLOCK/KVM_SET_CLOCK to separate functions
No functional change intended.

Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-10-01 03:44:47 -04:00
Paolo Bonzini
6b6fcd2804 kvm: x86: abstract locking around pvclock_update_vm_gtod_copy
Updates to the kvmclock parameters needs to do a complicated dance of
KVM_REQ_MCLOCK_INPROGRESS and KVM_REQ_CLOCK_UPDATE in addition to taking
pvclock_gtod_sync_lock.  Place that in two functions that can be called
on all of master clock update, KVM_SET_CLOCK, and Hyper-V reenlightenment.

Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-10-01 03:44:47 -04:00
Lai Jiangshan
3e44dce4d0 KVM: X86: Move PTE present check from loop body to __shadow_walk_next()
So far, the loop bodies already ensure the PTE is present before calling
__shadow_walk_next():  Some loop bodies simply exit with a !PRESENT
directly and some other loop bodies, i.e. FNAME(fetch) and __direct_map()
do not currently guard their walks with is_shadow_present_pte, but only
because they install present non-leaf SPTEs in the loop itself.

But checking pte present in __shadow_walk_next() (which is called from
shadow_walk_okay()) is more prudent; walking past a !PRESENT SPTE
would lead to attempting to read a the next level SPTE from a garbage
iter->shadow_addr.  It also allows to remove the is_shadow_present_pte()
checks from the loop bodies.

Reviewed-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com>
Message-Id: <20210906122547.263316-2-jiangshanlai@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-10-01 03:44:46 -04:00
Maxim Levitsky
5228eb96a4 KVM: x86: nSVM: implement nested TSC scaling
This was tested by booting a nested guest with TSC=1Ghz,
observing the clocks, and doing about 100 cycles of migration.

Note that qemu patch is needed to support migration because
of a new MSR that needs to be placed in the migration state.

The patch will be sent to the qemu mailing list soon.

Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Message-Id: <20210914154825.104886-14-mlevitsk@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-10-01 03:44:46 -04:00
Maxim Levitsky
f800650a4e KVM: x86: SVM: add module param to control TSC scaling
This allows to easily simulate a CPU without this feature.

Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Message-Id: <20210914154825.104886-13-mlevitsk@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-10-01 03:44:46 -04:00
Paolo Bonzini
36e8194dcd KVM: x86: SVM: don't set VMLOAD/VMSAVE intercepts on vCPU reset
Commit adc2a23734 ("KVM: nSVM: improve SYSENTER emulation on AMD"),
made init_vmcb set vmload/vmsave intercepts unconditionally,
and relied on svm_vcpu_after_set_cpuid to clear them when possible.

However init_vmcb is also called when the vCPU is reset, and it is
not followed by another call to svm_vcpu_after_set_cpuid because
the CPUID is already set.  This mistake makes the VMSAVE/VMLOAD intercept
to be set when it is not needed, and harms performance of the nested
guest.

Extract the relevant parts of svm_vcpu_after_set_cpuid so that they
can be called again on reset.

Fixes: adc2a23734 ("KVM: nSVM: improve SYSENTER emulation on AMD")
Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-10-01 03:37:34 -04:00
Masami Hiramatsu
bf094cffea x86/kprobes: Fixup return address in generic trampoline handler
In x86, the fake return address on the stack saved by
__kretprobe_trampoline() will be replaced with the real return
address after returning from trampoline_handler(). Before fixing
the return address, the real return address can be found in the
'current->kretprobe_instances'.

However, since there is a window between updating the
'current->kretprobe_instances' and fixing the address on the stack,
if an interrupt happens at that timing and the interrupt handler
does stacktrace, it may fail to unwind because it can not get
the correct return address from 'current->kretprobe_instances'.

This will eliminate that window by fixing the return address
right before updating 'current->kretprobe_instances'.

Link: https://lkml.kernel.org/r/163163057094.489837.9044470370440745866.stgit@devnote2

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Tested-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-09-30 21:24:08 -04:00
Masami Hiramatsu
19138af1bd x86/unwind: Recover kretprobe trampoline entry
Since the kretprobe replaces the function return address with
the kretprobe_trampoline on the stack, x86 unwinders can not
continue the stack unwinding at that point, or record
kretprobe_trampoline instead of correct return address.

To fix this issue, find the correct return address from task's
kretprobe_instances as like as function-graph tracer does.

With this fix, the unwinder can correctly unwind the stack
from kretprobe event on x86, as below.

           <...>-135     [003] ...1     6.722338: r_full_proxy_read_0: (vfs_read+0xab/0x1a0 <- full_proxy_read)
           <...>-135     [003] ...1     6.722377: <stack trace>
 => kretprobe_trace_func+0x209/0x2f0
 => kretprobe_dispatcher+0x4a/0x70
 => __kretprobe_trampoline_handler+0xca/0x150
 => trampoline_handler+0x44/0x70
 => kretprobe_trampoline+0x2a/0x50
 => vfs_read+0xab/0x1a0
 => ksys_read+0x5f/0xe0
 => do_syscall_64+0x33/0x40
 => entry_SYSCALL_64_after_hwframe+0x44/0xae

Link: https://lkml.kernel.org/r/163163055130.489837.5161749078833497255.stgit@devnote2

Reported-by: Daniel Xu <dxu@dxuuu.xyz>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Suggested-by: Josh Poimboeuf <jpoimboe@redhat.com>
Tested-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-09-30 21:24:07 -04:00
Masami Hiramatsu
1f36839308 x86/kprobes: Push a fake return address at kretprobe_trampoline
Change __kretprobe_trampoline() to push the address of the
__kretprobe_trampoline() as a fake return address at the bottom
of the stack frame. This fake return address will be replaced
with the correct return address in the trampoline_handler().

With this change, the ORC unwinder can check whether the return
address is modified by kretprobes or not.

Link: https://lkml.kernel.org/r/163163054185.489837.14338744048957727386.stgit@devnote2

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Suggested-by: Josh Poimboeuf <jpoimboe@redhat.com>
Tested-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-09-30 21:24:07 -04:00
Josh Poimboeuf
eb4a3f7d78 x86/kprobes: Add UNWIND_HINT_FUNC on kretprobe_trampoline()
Add UNWIND_HINT_FUNC on __kretprobe_trampoline() code so that ORC
information is generated on the __kretprobe_trampoline() correctly.
Also, this uses STACK_FRAME_NON_STANDARD_FP(), CONFIG_FRAME_POINTER-
-specific version of STACK_FRAME_NON_STANDARD().

Link: https://lkml.kernel.org/r/163163049242.489837.11970969750993364293.stgit@devnote2

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Tested-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-09-30 21:24:07 -04:00
Masami Hiramatsu
adf8a61a94 kprobes: treewide: Make it harder to refer kretprobe_trampoline directly
Since now there is kretprobe_trampoline_addr() for referring the
address of kretprobe trampoline code, we don't need to access
kretprobe_trampoline directly.

Make it harder to refer by renaming it to __kretprobe_trampoline().

Link: https://lkml.kernel.org/r/163163045446.489837.14510577516938803097.stgit@devnote2

Suggested-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-09-30 21:24:06 -04:00
Masami Hiramatsu
96fed8ac2b kprobes: treewide: Remove trampoline_address from kretprobe_trampoline_handler()
The __kretprobe_trampoline_handler() callback, called from low level
arch kprobes methods, has the 'trampoline_address' parameter, which is
entirely superfluous as it basically just replicates:

  dereference_kernel_function_descriptor(kretprobe_trampoline)

In fact we had bugs in arch code where it wasn't replicated correctly.

So remove this superfluous parameter and use kretprobe_trampoline_addr()
instead.

Link: https://lkml.kernel.org/r/163163044546.489837.13505751885476015002.stgit@devnote2

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Tested-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-09-30 21:24:06 -04:00
Masami Hiramatsu
c42421e205 kprobes: treewide: Use 'kprobe_opcode_t *' for the code address in get_optimized_kprobe()
Since get_optimized_kprobe() is only used inside kprobes,
it doesn't need to use 'unsigned long' type for 'addr' parameter.
Make it use 'kprobe_opcode_t *' for the 'addr' parameter and
subsequent call of arch_within_optimized_kprobe() also should use
'kprobe_opcode_t *'.

Note that MAX_OPTIMIZED_LENGTH and RELATIVEJUMP_SIZE are defined
by byte-size, but the size of 'kprobe_opcode_t' depends on the
architecture. Therefore, we must be careful when calculating
addresses using those macros.

Link: https://lkml.kernel.org/r/163163040680.489837.12133032364499833736.stgit@devnote2

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-09-30 21:24:05 -04:00
Jakub Kicinski
dd9a887b35 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
drivers/net/phy/bcm7xxx.c
  d88fd1b546 ("net: phy: bcm7xxx: Fixed indirect MMD operations")
  f68d08c437 ("net: phy: bcm7xxx: Add EPHY entry for 72165")

net/sched/sch_api.c
  b193e15ac6 ("net: prevent user from passing illegal stab size")
  69508d4333 ("net_sched: Use struct_size() and flex_array_size() helpers")

Both cases trivial - adjacent code additions.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-09-30 14:49:21 -07:00
Linus Torvalds
4de593fb96 Merge tag 'net-5.15-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Pull networking fixes from Jakub Kicinski:
 "Networking fixes, including fixes from mac80211, netfilter and bpf.

  Current release - regressions:

   - bpf, cgroup: assign cgroup in cgroup_sk_alloc when called from
     interrupt

   - mdio: revert mechanical patches which broke handling of optional
     resources

   - dev_addr_list: prevent address duplication

  Previous releases - regressions:

   - sctp: break out if skb_header_pointer returns NULL in sctp_rcv_ootb
     (NULL deref)

   - Revert "mac80211: do not use low data rates for data frames with no
     ack flag", fixing broadcast transmissions

   - mac80211: fix use-after-free in CCMP/GCMP RX

   - netfilter: include zone id in tuple hash again, minimize collisions

   - netfilter: nf_tables: unlink table before deleting it (race -> UAF)

   - netfilter: log: work around missing softdep backend module

   - mptcp: don't return sockets in foreign netns

   - sched: flower: protect fl_walk() with rcu (race -> UAF)

   - ixgbe: fix NULL pointer dereference in ixgbe_xdp_setup

   - smsc95xx: fix stalled rx after link change

   - enetc: fix the incorrect clearing of IF_MODE bits

   - ipv4: fix rtnexthop len when RTA_FLOW is present

   - dsa: mv88e6xxx: 6161: use correct MAX MTU config method for this
     SKU

   - e100: fix length calculation & buffer overrun in ethtool::get_regs

  Previous releases - always broken:

   - mac80211: fix using stale frag_tail skb pointer in A-MSDU tx

   - mac80211: drop frames from invalid MAC address in ad-hoc mode

   - af_unix: fix races in sk_peer_pid and sk_peer_cred accesses (race
     -> UAF)

   - bpf, x86: Fix bpf mapping of atomic fetch implementation

   - bpf: handle return value of BPF_PROG_TYPE_STRUCT_OPS prog

   - netfilter: ip6_tables: zero-initialize fragment offset

   - mhi: fix error path in mhi_net_newlink

   - af_unix: return errno instead of NULL in unix_create1() when over
     the fs.file-max limit

  Misc:

   - bpf: exempt CAP_BPF from checks against bpf_jit_limit

   - netfilter: conntrack: make max chain length random, prevent
     guessing buckets by attackers

   - netfilter: nf_nat_masquerade: make async masq_inet6_event handling
     generic, defer conntrack walk to work queue (prevent hogging RTNL
     lock)"

* tag 'net-5.15-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (77 commits)
  af_unix: fix races in sk_peer_pid and sk_peer_cred accesses
  net: stmmac: fix EEE init issue when paired with EEE capable PHYs
  net: dev_addr_list: handle first address in __hw_addr_add_ex
  net: sched: flower: protect fl_walk() with rcu
  net: introduce and use lock_sock_fast_nested()
  net: phy: bcm7xxx: Fixed indirect MMD operations
  net: hns3: disable firmware compatible features when uninstall PF
  net: hns3: fix always enable rx vlan filter problem after selftest
  net: hns3: PF enable promisc for VF when mac table is overflow
  net: hns3: fix show wrong state when add existing uc mac address
  net: hns3: fix mixed flag HCLGE_FLAG_MQPRIO_ENABLE and HCLGE_FLAG_DCB_ENABLE
  net: hns3: don't rollback when destroy mqprio fail
  net: hns3: remove tc enable checking
  net: hns3: do not allow call hns3_nic_net_open repeatedly
  ixgbe: Fix NULL pointer dereference in ixgbe_xdp_setup
  net: bridge: mcast: Associate the seqcount with its protecting lock.
  net: mdio-ipq4019: Fix the error for an optional regs resource
  net: hns3: fix hclge_dbg_dump_tm_pg() stack usage
  net: mdio: mscc-miim: Fix the mdio controller
  af_unix: Return errno instead of NULL in unix_create1().
  ...
2021-09-30 14:28:05 -07:00
Ard Biesheuvel
5443f98fb9 x86: add CPU field to struct thread_info
The CPU field will be moved back into thread_info even when
THREAD_INFO_IN_TASK is enabled, so add it back to x86's definition of
struct thread_info.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Acked-by: Borislav Petkov <bp@suse.de>
Acked-by: Mark Rutland <mark.rutland@arm.com>
2021-09-30 14:40:30 +02:00