[ Upstream commit 2f661f71fda1fc0c42b7746ca5b7da529eb6b5be ]
With some Infineon chips the timeouts in tpm_tis_send_data (both B and
C) can reach up to about 2250 ms.
Timeout C is retried since
commit de9e33df7762 ("tpm, tpm_tis: Workaround failed command reception on Infineon devices")
Timeout B still needs to be extended.
The problem is most commonly encountered with context related operation
such as load context/save context. These are issued directly by the
kernel, and there is no retry logic for them.
When a filesystem is set up to use the TPM for unlocking the boot fails,
and restarting the userspace service is ineffective. This is likely
because ignoring a load context/save context result puts the real TPM
state and the TPM state expected by the kernel out of sync.
Chips known to be affected:
tpm_tis IFX1522:00: 2.0 TPM (device-id 0x1D, rev-id 54)
Description: SLB9672
Firmware Revision: 15.22
tpm_tis MSFT0101:00: 2.0 TPM (device-id 0x1B, rev-id 22)
Firmware Revision: 7.83
tpm_tis MSFT0101:00: 2.0 TPM (device-id 0x1A, rev-id 16)
Firmware Revision: 5.63
Link: https://lore.kernel.org/linux-integrity/Z5pI07m0Muapyu9w@kitsune.suse.cz/
Signed-off-by: Michal Suchanek <msuchanek@suse.de>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit fd837de3c9cb1a162c69bc1fb1f438467fe7f2f5 ]
Since the shared trace_probe_log variable can be accessed and
modified via probe event create operation of kprobe_events,
uprobe_events, and dynamic_events, it should be protected.
In the dynamic_events, all operations are serialized by
`dyn_event_ops_mutex`. But kprobe_events and uprobe_events
interfaces are not serialized.
To solve this issue, introduces dyn_event_create(), which runs
create() operation under the mutex, for kprobe_events and
uprobe_events. This also uses lockdep to check the mutex is
held when using trace_probe_log* APIs.
Link: https://lore.kernel.org/all/174684868120.551552.3068655787654268804.stgit@devnote2/
Reported-by: Paul Cacheux <paulcacheux@gmail.com>
Closes: https://lore.kernel.org/all/20250510074456.805a16872b591e2971a4d221@kernel.org/
Fixes: ab105a4fb8 ("tracing: Use tracing error_log with probe events")
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit bfcfe6d335a967f8ea0c1980960e6f0205b5de6e ]
The wlan_ctrl_by_user detection was introduced by commit a50bd128f2
("asus-wmi: record wlan status while controlled by userapp").
Quoting from that commit's commit message:
"""
When you call WMIMethod(DSTS, 0x00010011) to get WLAN status, it may return
(1) 0x00050001 (On)
(2) 0x00050000 (Off)
(3) 0x00030001 (On)
(4) 0x00030000 (Off)
(5) 0x00000002 (Unknown)
(1), (2) means that the model has hardware GPIO for WLAN, you can call
WMIMethod(DEVS, 0x00010011, 1 or 0) to turn WLAN on/off.
(3), (4) means that the model doesn’t have hardware GPIO, you need to use
API or driver library to turn WLAN on/off, and call
WMIMethod(DEVS, 0x00010012, 1 or 0) to set WLAN LED status.
After you set WLAN LED status, you can see the WLAN status is changed with
WMIMethod(DSTS, 0x00010011). Because the status is recorded lastly
(ex: Windows), you can use it for synchronization.
(5) means that the model doesn’t have WLAN device.
WLAN is the ONLY special case with upper rule.
"""
The wlan_ctrl_by_user flag should be set on 0x0003000? ((3), (4) above)
return values, but the flag mistakenly also gets set on laptops with
0x0005000? ((1), (2)) return values. This is causing rfkill problems on
laptops where 0x0005000? is returned.
Fix the check to only set the wlan_ctrl_by_user flag for 0x0003000?
return values.
Fixes: a50bd128f2 ("asus-wmi: record wlan status while controlled by userapp")
Link: https://bugzilla.kernel.org/show_bug.cgi?id=219786
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Armin Wolf <W_Armin@gmx.de>
Link: https://lore.kernel.org/r/20250501131702.103360-2-hdegoede@redhat.com
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 11854fe263eb1b9a8efa33b0c087add7719ea9b4 ]
In commit bbdc6076d2 ("binfmt_elf: move brk out of mmap when doing
direct loader exec"), the brk was moved out of the mmap region when
loading static PIE binaries (ET_DYN without INTERP). The common case
for these binaries was testing new ELF loaders, so the brk needed to
be away from mmap to avoid colliding with stack, future mmaps (of the
loader-loaded binary), etc. But this was only done when ASLR was enabled,
in an attempt to minimize changes to memory layouts.
After adding support to respect alignment requirements for static PIE
binaries in commit 3545deff0ec7 ("binfmt_elf: Honor PT_LOAD alignment
for static PIE"), it became possible to have a large gap after the
final PT_LOAD segment and the top of the mmap region. This means that
future mmap allocations might go after the last PT_LOAD segment (where
brk might be if ASLR was disabled) instead of before them (where they
traditionally ended up).
On arm64, running with ASLR disabled, Ubuntu 22.04's "ldconfig" binary,
a static PIE, has alignment requirements that leaves a gap large enough
after the last PT_LOAD segment to fit the vdso and vvar, but still leave
enough space for the brk (which immediately follows the last PT_LOAD
segment) to be allocated by the binary.
fffff7f20000-fffff7fde000 r-xp 00000000 fe:02 8110426 /sbin/ldconfig.real
fffff7fee000-fffff7ff5000 rw-p 000be000 fe:02 8110426 /sbin/ldconfig.real
fffff7ff5000-fffff7ffa000 rw-p 00000000 00:00 0
***[brk will go here at fffff7ffa000]***
fffff7ffc000-fffff7ffe000 r--p 00000000 00:00 0 [vvar]
fffff7ffe000-fffff8000000 r-xp 00000000 00:00 0 [vdso]
fffffffdf000-1000000000000 rw-p 00000000 00:00 0 [stack]
After commit 0b3bc3354eb9 ("arm64: vdso: Switch to generic storage
implementation"), the arm64 vvar grew slightly, and suddenly the brk
collided with the allocation.
fffff7f20000-fffff7fde000 r-xp 00000000 fe:02 8110426 /sbin/ldconfig.real
fffff7fee000-fffff7ff5000 rw-p 000be000 fe:02 8110426 /sbin/ldconfig.real
fffff7ff5000-fffff7ffa000 rw-p 00000000 00:00 0
***[oops, no room any more, vvar is at fffff7ffa000!]***
fffff7ffa000-fffff7ffe000 r--p 00000000 00:00 0 [vvar]
fffff7ffe000-fffff8000000 r-xp 00000000 00:00 0 [vdso]
fffffffdf000-1000000000000 rw-p 00000000 00:00 0 [stack]
The solution is to unconditionally move the brk out of the mmap region
for static PIE binaries. Whether ASLR is enabled or not does not change if
there may be future mmap allocation collisions with a growing brk region.
Update memory layout comments (with kernel-doc headings), consolidate
the setting of mm->brk to later (it isn't needed early), move static PIE
brk out of mmap unconditionally, and make sure brk(2) knows to base brk
position off of mm->start_brk not mm->end_data no matter what the cause of
moving it is (via current->brk_randomized).
For the CONFIG_COMPAT_BRK case, though, leave the logic unchanged, as we
can never safely move the brk. These systems, however, are not using
specially aligned static PIE binaries.
Reported-by: Ryan Roberts <ryan.roberts@arm.com>
Closes: https://lore.kernel.org/lkml/f93db308-4a0e-4806-9faf-98f890f5a5e6@arm.com/
Fixes: bbdc6076d2 ("binfmt_elf: move brk out of mmap when doing direct loader exec")
Link: https://lore.kernel.org/r/20250425224502.work.520-kees@kernel.org
Reviewed-by: Ryan Roberts <ryan.roberts@arm.com>
Tested-by: Ryan Roberts <ryan.roberts@arm.com>
Signed-off-by: Kees Cook <kees@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 3545deff0ec7a37de7ed9632e262598582b140e9 ]
The p_align values in PT_LOAD were ignored for static PIE executables
(i.e. ET_DYN without PT_INTERP). This is because there is no way to
request a non-fixed mmap region with a specific alignment. ET_DYN with
PT_INTERP uses a separate base address (ELF_ET_DYN_BASE) and binfmt_elf
performs the ASLR itself, which means it can also apply alignment. For
the mmap region, the address selection happens deep within the vm_mmap()
implementation (when the requested address is 0).
The earlier attempt to implement this:
commit 9630f0d60f ("fs/binfmt_elf: use PT_LOAD p_align values for static PIE")
commit 925346c129 ("fs/binfmt_elf: fix PT_LOAD p_align values for loaders")
did not take into account the different base address origins, and were
eventually reverted:
aeb7923733 ("revert "fs/binfmt_elf: use PT_LOAD p_align values for static PIE"")
In order to get the correct alignment from an mmap base, binfmt_elf must
perform a 0-address load first, then tear down the mapping and perform
alignment on the resulting address. Since this is slightly more overhead,
only do this when it is needed (i.e. the alignment is not the default
ELF alignment). This does, however, have the benefit of being able to
use MAP_FIXED_NOREPLACE, to avoid potential collisions.
With this fixed, enable the static PIE self tests again.
Reported-by: H.J. Lu <hjl.tools@gmail.com>
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=215275
Link: https://lore.kernel.org/r/20240508173149.677910-3-keescook@chromium.org
Signed-off-by: Kees Cook <kees@kernel.org>
Stable-dep-of: 11854fe263eb ("binfmt_elf: Move brk for static PIE even if ASLR disabled")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 2d4cf7b190bbfadd4986bf5c34da17c1a88adf8e ]
In preparation to support PT_LOAD with large p_align values on
non-PT_INTERP ET_DYN executables (i.e. "static pie"), we'll need to use
the total_size details earlier. Move this separately now to make the
next patch more readable. As total_size and load_bias are currently
calculated separately, this has no behavioral impact.
Link: https://lore.kernel.org/r/20240508173149.677910-2-keescook@chromium.org
Signed-off-by: Kees Cook <kees@kernel.org>
Stable-dep-of: 11854fe263eb ("binfmt_elf: Move brk for static PIE even if ASLR disabled")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit b57a2907c9d96c56494ef25f8ec821cd0b355dd6 ]
After commit 4d1cd3b2c5 ("tools/testing/selftests/exec: fix link
error"), the load address alignment tests tried to build statically.
This was silently ignored in some cases. However, after attempting to
further fix the build by switching to "-static-pie", the test started
failing. This appears to be due to non-PT_INTERP ET_DYN execs ("static
PIE") not doing alignment correctly, which remains unfixed[1]. See commit
aeb7923733 ("revert "fs/binfmt_elf: use PT_LOAD p_align values for
static PIE"") for more details.
Provide rules to build both static and non-static PIE binaries, improve
debug reporting, and perform several test steps instead of a single
all-or-nothing test. However, do not actually enable static-pie tests;
alignment specification is only supported for ET_DYN with PT_INTERP
("regular PIE").
Link: https://bugzilla.kernel.org/show_bug.cgi?id=215275 [1]
Link: https://lore.kernel.org/r/20240508173149.677910-1-keescook@chromium.org
Signed-off-by: Kees Cook <kees@kernel.org>
Stable-dep-of: 11854fe263eb ("binfmt_elf: Move brk for static PIE even if ASLR disabled")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 585a018627b4d7ed37387211f667916840b5c5ea ]
Implement a helper elf_load() that wraps elf_map() and performs all
of the necessary work to ensure that when "memsz > filesz" the bytes
described by "memsz > filesz" are zeroed.
An outstanding issue is if the first segment has filesz 0, and has a
randomized location. But that is the same as today.
In this change I replaced an open coded padzero() that did not clear
all of the way to the end of the page, with padzero() that does.
I also stopped checking the return of padzero() as there is at least
one known case where testing for failure is the wrong thing to do.
It looks like binfmt_elf_fdpic may have the proper set of tests
for when error handling can be safely completed.
I found a couple of commits in the old history
https://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.git,
that look very interesting in understanding this code.
commit 39b56d902bf3 ("[PATCH] binfmt_elf: clearing bss may fail")
commit c6e2227e4a3e ("[SPARC64]: Missing user access return value checks in fs/binfmt_elf.c and fs/compat.c")
commit 5bf3be033f50 ("v2.4.10.1 -> v2.4.10.2")
Looking at commit 39b56d902bf3 ("[PATCH] binfmt_elf: clearing bss may fail"):
> commit 39b56d902bf35241e7cba6cc30b828ed937175ad
> Author: Pavel Machek <pavel@ucw.cz>
> Date: Wed Feb 9 22:40:30 2005 -0800
>
> [PATCH] binfmt_elf: clearing bss may fail
>
> So we discover that Borland's Kylix application builder emits weird elf
> files which describe a non-writeable bss segment.
>
> So remove the clear_user() check at the place where we zero out the bss. I
> don't _think_ there are any security implications here (plus we've never
> checked that clear_user() return value, so whoops if it is a problem).
>
> Signed-off-by: Pavel Machek <pavel@suse.cz>
> Signed-off-by: Andrew Morton <akpm@osdl.org>
> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
It seems pretty clear that binfmt_elf_fdpic with skipping clear_user() for
non-writable segments and otherwise calling clear_user(), aka padzero(),
and checking it's return code is the right thing to do.
I just skipped the error checking as that avoids breaking things.
And notably, it looks like Borland's Kylix died in 2005 so it might be
safe to just consider read-only segments with memsz > filesz an error.
Reported-by: Sebastian Ott <sebott@redhat.com>
Reported-by: Thomas Weißschuh <linux@weissschuh.net>
Closes: https://lkml.kernel.org/r/20230914-bss-alloc-v1-1-78de67d2c6dd@weissschuh.net
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Link: https://lore.kernel.org/r/87sf71f123.fsf@email.froward.int.ebiederm.org
Tested-by: Pedro Falcato <pedro.falcato@gmail.com>
Signed-off-by: Sebastian Ott <sebott@redhat.com>
Link: https://lore.kernel.org/r/20230929032435.2391507-1-keescook@chromium.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Stable-dep-of: 11854fe263eb ("binfmt_elf: Move brk for static PIE even if ASLR disabled")
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit e52c1dc7455d32c8a55f9949d300e5e87d011fa6 upstream.
FineIBT-paranoid was using the retpoline bytes for the paranoid check,
disabling retpolines, because all parts that have IBT also have eIBRS
and thus don't need no stinking retpolines.
Except... ITS needs the retpolines for indirect calls must not be in
the first half of a cacheline :-/
So what was the paranoid call sequence:
<fineibt_paranoid_start>:
0: 41 ba 78 56 34 12 mov $0x12345678, %r10d
6: 45 3b 53 f7 cmp -0x9(%r11), %r10d
a: 4d 8d 5b <f0> lea -0x10(%r11), %r11
e: 75 fd jne d <fineibt_paranoid_start+0xd>
10: 41 ff d3 call *%r11
13: 90 nop
Now becomes:
<fineibt_paranoid_start>:
0: 41 ba 78 56 34 12 mov $0x12345678, %r10d
6: 45 3b 53 f7 cmp -0x9(%r11), %r10d
a: 4d 8d 5b f0 lea -0x10(%r11), %r11
e: 2e e8 XX XX XX XX cs call __x86_indirect_paranoid_thunk_r11
Where the paranoid_thunk looks like:
1d: <ea> (bad)
__x86_indirect_paranoid_thunk_r11:
1e: 75 fd jne 1d
__x86_indirect_its_thunk_r11:
20: 41 ff eb jmp *%r11
23: cc int3
[ dhansen: remove initialization to false ]
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
[ Just a portion of the original commit, in order to fix a build issue
in stable kernels due to backports ]
Tested-by: Holger Hoffstätte <holger@applied-asynchrony.com>
Link: https://lore.kernel.org/r/20250514113952.GB16434@noisy.programming.kicks-ass.net
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 4ba89dd6dd upstream.
The following commit
095b8303f3 ("x86/alternative: Make custom return thunk unconditional")
made '__x86_return_thunk' a placeholder value. All code setting
X86_FEATURE_RETHUNK also changes the value of 'x86_return_thunk'. So
the optimization at the beginning of apply_returns() is dead code.
Also, before the above-mentioned commit, the optimization actually had a
bug It bypassed __static_call_fixup(), causing some raw returns to
remain unpatched in static call trampolines. Thus the 'Fixes' tag.
Fixes: d2408e043e ("x86/alternative: Optimize returns patching")
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Acked-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/16d19d2249d4485d8380fb215ffaae81e6b8119e.1693889988.git.jpoimboe@kernel.org
Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 872df34d7c51a79523820ea6a14860398c639b87 upstream.
ITS mitigation moves the unsafe indirect branches to a safe thunk. This
could degrade the prediction accuracy as the source address of indirect
branches becomes same for different execution paths.
To improve the predictions, and hence the performance, assign a separate
thunk for each indirect callsite. This is also a defense-in-depth measure
to avoid indirect branches aliasing with each other.
As an example, 5000 dynamic thunks would utilize around 16 bits of the
address space, thereby gaining entropy. For a BTB that uses
32 bits for indexing, dynamic thunks could provide better prediction
accuracy over fixed thunks.
Have ITS thunks be variable sized and use EXECMEM_MODULE_TEXT such that
they are both more flexible (got to extend them later) and live in 2M TLBs,
just like kernel code, avoiding undue TLB pressure.
[ pawan: CONFIG_EXECMEM and CONFIG_EXECMEM_ROX are not supported on
backport kernel, made changes to use module_alloc() and
set_memory_*() for dynamic thunks. ]
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit ebebe30794d38c51f71fe4951ba6af4159d9837d upstream.
cfi_rewrite_callers() updates the fineIBT hash matching at the caller side,
but except for paranoid-mode it relies on apply_retpoline() and friends for
any ENDBR relocation. This could temporarily cause an indirect branch to
land on a poisoned ENDBR.
For instance, with para-virtualization enabled, a simple wrmsrl() could
have an indirect branch pointing to native_write_msr() who's ENDBR has been
relocated due to fineIBT:
<wrmsrl>:
push %rbp
mov %rsp,%rbp
mov %esi,%eax
mov %rsi,%rdx
shr $0x20,%rdx
mov %edi,%edi
mov %rax,%rsi
call *0x21e65d0(%rip) # <pv_ops+0xb8>
^^^^^^^^^^^^^^^^^^^^^^^
Such an indirect call during the alternative patching could #CP if the
caller is not *yet* adjusted for the new target ENDBR. To prevent a false
#CP, keep CET-IBT disabled until all callers are patched.
Patching during the module load does not need to be guarded by IBT-disable
because the module code is not executed until the patching is complete.
[ pawan: Since apply_paravirt() happens before __apply_fineibt()
relocates the ENDBR, pv_ops in the example above is not relevant.
It is still safer to keep this commit because missing an ENDBR
means an oops. ]
Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit f0cd7091cc5a032c8870b4285305d9172569d126 upstream.
The software mitigation for BHI is to execute BHB clear sequence at syscall
entry, and possibly after a cBPF program. ITS mitigation thunks RETs in the
lower half of the cacheline. This causes the RETs in the BHB clear sequence
to be thunked as well, adding unnecessary branches to the BHB clear
sequence.
Since the sequence is in hot path, align the RET instructions in the
sequence to avoid thunking.
This is how disassembly clear_bhb_loop() looks like after this change:
0x44 <+4>: mov $0x5,%ecx
0x49 <+9>: call 0xffffffff81001d9b <clear_bhb_loop+91>
0x4e <+14>: jmp 0xffffffff81001de5 <clear_bhb_loop+165>
0x53 <+19>: int3
...
0x9b <+91>: call 0xffffffff81001dce <clear_bhb_loop+142>
0xa0 <+96>: ret
0xa1 <+97>: int3
...
0xce <+142>: mov $0x5,%eax
0xd3 <+147>: jmp 0xffffffff81001dd6 <clear_bhb_loop+150>
0xd5 <+149>: nop
0xd6 <+150>: sub $0x1,%eax
0xd9 <+153>: jne 0xffffffff81001dd3 <clear_bhb_loop+147>
0xdb <+155>: sub $0x1,%ecx
0xde <+158>: jne 0xffffffff81001d9b <clear_bhb_loop+91>
0xe0 <+160>: ret
0xe1 <+161>: int3
0xe2 <+162>: int3
0xe3 <+163>: int3
0xe4 <+164>: int3
0xe5 <+165>: lfence
0xe8 <+168>: pop %rbp
0xe9 <+169>: ret
Suggested-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 2665281a07e19550944e8354a2024635a7b2714a upstream.
Ice Lake generation CPUs are not affected by guest/host isolation part of
ITS. If a user is only concerned about KVM guests, they can now choose a
new cmdline option "vmexit" that will not deploy the ITS mitigation when
CPU is not affected by guest/host isolation. This saves the performance
overhead of ITS mitigation on Ice Lake gen CPUs.
When "vmexit" option selected, if the CPU is affected by ITS guest/host
isolation, the default ITS mitigation is deployed.
Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Josh Poimboeuf <jpoimboe@kernel.org>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit f4818881c47fd91fcb6d62373c57c7844e3de1c0 upstream.
Indirect Target Selection (ITS) is a bug in some pre-ADL Intel CPUs with
eIBRS. It affects prediction of indirect branch and RETs in the
lower half of cacheline. Due to ITS such branches may get wrongly predicted
to a target of (direct or indirect) branch that is located in the upper
half of the cacheline.
Scope of impact
===============
Guest/host isolation
--------------------
When eIBRS is used for guest/host isolation, the indirect branches in the
VMM may still be predicted with targets corresponding to branches in the
guest.
Intra-mode
----------
cBPF or other native gadgets can be used for intra-mode training and
disclosure using ITS.
User/kernel isolation
---------------------
When eIBRS is enabled user/kernel isolation is not impacted.
Indirect Branch Prediction Barrier (IBPB)
-----------------------------------------
After an IBPB, indirect branches may be predicted with targets
corresponding to direct branches which were executed prior to IBPB. This is
mitigated by a microcode update.
Add cmdline parameter indirect_target_selection=off|on|force to control the
mitigation to relocate the affected branches to an ITS-safe thunk i.e.
located in the upper half of cacheline. Also add the sysfs reporting.
When retpoline mitigation is deployed, ITS safe-thunks are not needed,
because retpoline sequence is already ITS-safe. Similarly, when call depth
tracking (CDT) mitigation is deployed (retbleed=stuff), ITS safe return
thunk is not used, as CDT prevents RSB-underflow.
To not overcomplicate things, ITS mitigation is not supported with
spectre-v2 lfence;jmp mitigation. Moreover, it is less practical to deploy
lfence;jmp mitigation on ITS affected parts anyways.
Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Josh Poimboeuf <jpoimboe@kernel.org>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit a75bf27fe41abe658c53276a0c486c4bf9adecfc upstream.
RETs in the lower half of cacheline may be affected by ITS bug,
specifically when the RSB-underflows. Use ITS-safe return thunk for such
RETs.
RETs that are not patched:
- RET in retpoline sequence does not need to be patched, because the
sequence itself fills an RSB before RET.
- RET in Call Depth Tracking (CDT) thunks __x86_indirect_{call|jump}_thunk
and call_depth_return_thunk are not patched because CDT by design
prevents RSB-underflow.
- RETs in .init section are not reachable after init.
- RETs that are explicitly marked safe with ANNOTATE_UNRET_SAFE.
Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Josh Poimboeuf <jpoimboe@kernel.org>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 8754e67ad4ac692c67ff1f99c0d07156f04ae40c upstream.
Due to ITS, indirect branches in the lower half of a cacheline may be
vulnerable to branch target injection attack.
Introduce ITS-safe thunks to patch indirect branches in the lower half of
cacheline with the thunk. Also thunk any eBPF generated indirect branches
in emit_indirect_jump().
Below category of indirect branches are not mitigated:
- Indirect branches in the .init section are not mitigated because they are
discarded after boot.
- Indirect branches that are explicitly marked retpoline-safe.
Note that retpoline also mitigates the indirect branches against ITS. This
is because the retpoline sequence fills an RSB entry before RET, and it
does not suffer from RSB-underflow part of the ITS.
Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Josh Poimboeuf <jpoimboe@kernel.org>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 159013a7ca18c271ff64192deb62a689b622d860 upstream.
ITS bug in some pre-Alderlake Intel CPUs may allow indirect branches in the
first half of a cache line get predicted to a target of a branch located in
the second half of the cache line.
Set X86_BUG_ITS on affected CPUs. Mitigation to follow in later commits.
Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Josh Poimboeuf <jpoimboe@kernel.org>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit c8c81458863ab686cda4fe1e603fccaae0f12460 upstream.
Commit:
010c4a461c1d ("x86/speculation: Simplify and make CALL_NOSPEC consistent")
added an #ifdef CONFIG_RETPOLINE around the CALL_NOSPEC definition. This is
not required as this code is already under a larger #ifdef.
Remove the extra #ifdef, no functional change.
vmlinux size remains same before and after this change:
CONFIG_RETPOLINE=y:
text data bss dec hex filename
25434752 7342290 2301212 35078254 217406e vmlinux.before
25434752 7342290 2301212 35078254 217406e vmlinux.after
# CONFIG_RETPOLINE is not set:
text data bss dec hex filename
22943094 6214994 1550152 30708240 1d49210 vmlinux.before
22943094 6214994 1550152 30708240 1d49210 vmlinux.after
[ pawan: s/CONFIG_MITIGATION_RETPOLINE/CONFIG_RETPOLINE/ ]
Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Josh Poimboeuf <jpoimboe@kernel.org>
Link: https://lore.kernel.org/r/20250320-call-nospec-extra-ifdef-v1-1-d9b084d24820@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit cfceff8526a426948b53445c02bcb98453c7330d upstream.
CALL_NOSPEC macro is used to generate Spectre-v2 mitigation friendly
indirect branches. At compile time the macro defaults to indirect branch,
and at runtime those can be patched to thunk based mitigations.
This approach is opposite of what is done for the rest of the kernel, where
the compile time default is to replace indirect calls with retpoline thunk
calls.
Make CALL_NOSPEC consistent with the rest of the kernel, default to
retpoline thunk at compile time when CONFIG_RETPOLINE is
enabled.
[ pawan: s/CONFIG_MITIGATION_RETPOLINE/CONFIG_RETPOLINE/ ]
Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Andrew Cooper <andrew.cooper3@citrix.com
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250228-call-nospec-v3-1-96599fed0f33@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 073fdbe02c69c43fb7c0d547ec265c7747d4a646 upstream.
With the possibility of intra-mode BHI via cBPF, complete mitigation for
BHI is to use IBHF (history fence) instruction with BHI_DIS_S set. Since
this new instruction is only available in 64-bit mode, setting BHI_DIS_S in
32-bit mode is only a partial mitigation.
Do not set BHI_DIS_S in 32-bit mode so as to avoid reporting misleading
mitigated status. With this change IBHF won't be used in 32-bit mode, also
remove the CONFIG_X86_64 check from emit_spectre_bhb_barrier().
Suggested-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Josh Poimboeuf <jpoimboe@kernel.org>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 9f725eec8fc0b39bdc07dcc8897283c367c1a163 upstream.
Classic BPF programs can be run by unprivileged users, allowing
unprivileged code to execute inside the kernel. Attackers can use this to
craft branch history in kernel mode that can influence the target of
indirect branches.
BHI_DIS_S provides user-kernel isolation of branch history, but cBPF can be
used to bypass this protection by crafting branch history in kernel mode.
To stop intra-mode attacks via cBPF programs, Intel created a new
instruction Indirect Branch History Fence (IBHF). IBHF prevents the
predicted targets of subsequent indirect branches from being influenced by
branch history prior to the IBHF. IBHF is only effective while BHI_DIS_S is
enabled.
Add the IBHF instruction to cBPF jitted code's exit path. Add the new fence
when the hardware mitigation is enabled (i.e., X86_FEATURE_CLEAR_BHB_HW is
set) or after the software sequence (X86_FEATURE_CLEAR_BHB_LOOP) is being
used in a virtual machine. Note that X86_FEATURE_CLEAR_BHB_HW and
X86_FEATURE_CLEAR_BHB_LOOP are mutually exclusive, so the JIT compiler will
only emit the new fence, not the SW sequence, when X86_FEATURE_CLEAR_BHB_HW
is set.
Hardware that enumerates BHI_NO basically has BHI_DIS_S protections always
enabled, regardless of the value of BHI_DIS_S. Since BHI_DIS_S doesn't
protect against intra-mode attacks, enumerate BHI bug on BHI_NO hardware as
well.
Signed-off-by: Daniel Sneddon <daniel.sneddon@linux.intel.com>
Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit d4e89d212d401672e9cdfe825d947ee3a9fbe3f5 upstream.
Classic BPF programs have been identified as potential vectors for
intra-mode Branch Target Injection (BTI) attacks. Classic BPF programs can
be run by unprivileged users. They allow unprivileged code to execute
inside the kernel. Attackers can use unprivileged cBPF to craft branch
history in kernel mode that can influence the target of indirect branches.
Introduce a branch history buffer (BHB) clearing sequence during the JIT
compilation of classic BPF programs. The clearing sequence is the same as
is used in previous mitigations to protect syscalls. Since eBPF programs
already have their own mitigations in place, only insert the call on
classic programs that aren't run by privileged users.
Signed-off-by: Daniel Sneddon <daniel.sneddon@linux.intel.com>
Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit f300769ead032513a68e4a02e806393402e626f8 upstream.
Support for eBPF programs loaded by unprivileged users is typically
disabled. This means only cBPF programs need to be mitigated for BHB.
In addition, only mitigate cBPF programs that were loaded by an
unprivileged user. Privileged users can also load the same program
via eBPF, making the mitigation pointless.
Signed-off-by: James Morse <james.morse@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 0dfefc2ea2f29ced2416017d7e5b1253a54c2735 upstream.
A malicious BPF program may manipulate the branch history to influence
what the hardware speculates will happen next.
On exit from a BPF program, emit the BHB mititgation sequence.
This is only applied for 'classic' cBPF programs that are loaded by
seccomp.
Signed-off-by: James Morse <james.morse@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit a1152be30a043d2d4dcb1683415f328bf3c51978 upstream.
Add a helper to expose the k value of the branchy loop. This is needed
by the BPF JIT to generate the mitigation sequence in BPF programs.
Signed-off-by: James Morse <james.morse@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit e7956c92f396a44eeeb6eaf7a5b5e1ad24db6748 upstream.
is_spectre_bhb_fw_affected() allows the caller to determine if the CPU
is known to need a firmware mitigation. CPUs are either on the list
of CPUs we know about, or firmware has been queried and reported that
the platform is affected - and mitigated by firmware.
This helper is not useful to determine if the platform is mitigated
by firmware. A CPU could be on the know list, but the firmware may
not be implemented. Its affected but not mitigated.
spectre_bhb_enable_mitigation() handles this distinction by checking
the firmware state before enabling the mitigation.
Add a helper to expose this state. This will be used by the BPF JIT
to determine if calling firmware for a mitigation is necessary and
supported.
Signed-off-by: James Morse <james.morse@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 63de8abd97ddb9b758bd8f915ecbd18e1f1a87a0 upstream.
To generate code in the eBPF epilogue that uses the DSB instruction,
insn.c needs a heler to encode the type and domain.
Re-use the crm encoding logic from the DMB instruction.
Signed-off-by: James Morse <james.morse@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit 687b2bae0efff9b25e071737d6af5004e6e35af5 upstream.
Multishot normally uses io_req_post_cqe() to post completions, but when
stopping it, it may finish up with a deferred completion. This is fine,
except if another multishot event triggers before the deferred completions
get flushed. If this occurs, then CQEs may get reordered in the CQ ring,
and cause confusion on the application side.
When multishot posting via io_req_post_cqe(), flush any pending deferred
completions first, if any.
Cc: stable@vger.kernel.org # 6.1+
Reported-by: Norman Maurer <norman_maurer@apple.com>
Reported-by: Christian Mazakas <christian.mazakas@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit b53e523261bf058ea4a518b482222e7a277b186b upstream.
There are a few spots where linked timeouts are armed, and not all of
them adhere to the pre-arm, attempt issue, post-arm pattern. This can
be problematic if the linked request returns that it will trigger a
callback later, and does so before the linked timeout is fully armed.
Consolidate all the linked timeout handling into __io_issue_sqe(),
rather than have it spread throughout the various issue entry points.
Cc: stable@vger.kernel.org
Link: https://github.com/axboe/liburing/issues/1390
Reported-by: Chase Hiltz <chase@path.net>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 65781e19dcfcb4aed1167d87a3ffcc2a0c071d47 ]
do_umount() analogue of the race fixed in 119e1ef80e "fix
__legitimize_mnt()/mntput() race". Here we want to make sure that
if __legitimize_mnt() doesn't notice our lock_mount_hash(), we will
notice their refcount increment. Harder to hit than mntput_no_expire()
one, fortunately, and consequences are milder (sync umount acting
like umount -l on a rare race with RCU pathwalk hitting at just the
wrong time instead of use-after-free galore mntput_no_expire()
counterpart used to be hit). Still a bug...
Fixes: 48a066e72d ("RCU'd vfsmounts")
Reviewed-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 650415fca0a97472fdd79725e35152614d1aad76 ]
The original nvme subsystem design didn't have a CONNECTING state; the
state machine allowed transitions from RESETTING to LIVE directly.
With the introduction of nvme fabrics the CONNECTING state was
introduce. Over time the nvme-pci started to use the CONNECTING state as
well.
Eventually, a bug fix for the nvme-fc started to depend that the only
valid transition to LIVE was from CONNECTING. Though this change didn't
update the firmware update handler which was still depending on
RESETTING to LIVE transition.
The simplest way to address it for the time being is to switch into
CONNECTING state before going to LIVE state.
Fixes: d2fe192348f9 ("nvme: only allow entering LIVE from CONNECTING state")
Reported-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Daniel Wagner <wagi@kernel.org>
Closes: https://lore.kernel.org/all/0134ea15-8d5f-41f7-9e9a-d7e6d82accaa@roeck-us.net
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit c44572e0cc13c9afff83fd333135a0aa9b27ba26 ]
Fix MAX_REG_OFFSET to point to the last register in 'pt_regs' and not to
the marker itself, which could allow regs_get_register() to return an
invalid offset.
Fixes: 40e084a506 ("MIPS: Add uprobes support.")
Suggested-by: Maciej W. Rozycki <macro@orcam.me.uk>
Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit f79aeb6c631b57395f37acbfbe59727e355a714c ]
The trick of using __aligned(IIO_DMA_MINALIGN) ensures that there is
no overlap between buffers used for DMA and those used for driver
state storage that are before the marking. It doesn't ensure
anything above state variables found after the marking. Hence
move this particular bit of state earlier in the structure.
Fixes: 10897f3430 ("iio: temp: maxim_thermocouple: Fix alignment for DMA safety")
Reviewed-by: David Lechner <dlechner@baylibre.com>
Link: https://patch.msgid.link/20250413103443.2420727-14-jic23@kernel.org
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
