linux-stable.git/drivers/char, branch v5.10.261 Linux kernel stable tree tpm: Make the TPM character devices non-seekable 2026-07-24T13:49:12+00:00 Jaewon Yang yong010301@gmail.com 2026-07-12T17:11:47+00:00 ed0ffc2c016629e40ba041ed0424a772d8b02e2c commit f20d61c22bcaf172d6790b6500e3838e532e71c8 upstream. The TPM character devices expose a sequential command/response interface, but their open handlers leave FMODE_PREAD and FMODE_PWRITE enabled. After a command leaves a response pending, pread(fd, buf, 16, 0x1400) passes 0x1400 as *off to tpm_common_read(). The transfer length is bounded by response_length, but the offset is used unchecked when forming data_buffer + *off. A sufficiently large offset therefore causes an out-of-bounds heap read through copy_to_user() and, if the copy succeeds, an out-of-bounds zero-write through the following memset(). Positional I/O does not provide coherent semantics for this interface. An arbitrary pread offset cannot represent how much of a response has been consumed sequentially. The write callback always stores a command at the start of data_buffer, while pwrite() does not update file->f_pos and can leave the sequential read cursor stale. Call nonseekable_open() from both open handlers. This removes FMODE_PREAD and FMODE_PWRITE, causing positional reads and writes to fail with -ESPIPE before reaching the TPM callbacks, and explicitly marks the files non-seekable. Normal read() and write() continue to use the existing sequential f_pos cursor, leaving the response state machine unchanged. Tested on Linux 6.12 with KASAN and a swtpm TPM2 device: - sequential partial reads returned the complete response - pread() and preadv() with offset 0x1400 returned -ESPIPE - pwrite() and pwritev() with offset zero returned -ESPIPE - the pending response remained intact after the rejected operations - a subsequent normal command/response cycle completed normally - no KASAN report was produced. Fixes: 9488585b21be ("tpm: add support for partial reads") Link: https://lore.kernel.org/all/20260710090217.191289-1-yong010301@gmail.com/ Cc: stable@vger.kernel.org Signed-off-by: Jaewon Yang <yong010301@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit f20d61c22bcaf172d6790b6500e3838e532e71c8 upstream.

The TPM character devices expose a sequential command/response
interface, but their open handlers leave FMODE_PREAD and FMODE_PWRITE
enabled.

After a command leaves a response pending, pread(fd, buf, 16, 0x1400)
passes 0x1400 as *off to tpm_common_read(). The transfer length is
bounded by response_length, but the offset is used unchecked when
forming data_buffer + *off. A sufficiently large offset therefore causes
an out-of-bounds heap read through copy_to_user() and, if the copy
succeeds, an out-of-bounds zero-write through the following memset().

Positional I/O does not provide coherent semantics for this interface.
An arbitrary pread offset cannot represent how much of a response has
been consumed sequentially. The write callback always stores a command
at the start of data_buffer, while pwrite() does not update file->f_pos
and can leave the sequential read cursor stale.

Call nonseekable_open() from both open handlers. This removes
FMODE_PREAD and FMODE_PWRITE, causing positional reads and writes to
fail with -ESPIPE before reaching the TPM callbacks, and explicitly
marks the files non-seekable. Normal read() and write() continue to use
the existing sequential f_pos cursor, leaving the response state machine
unchanged.

Tested on Linux 6.12 with KASAN and a swtpm TPM2 device:

 - sequential partial reads returned the complete response
 - pread() and preadv() with offset 0x1400 returned -ESPIPE
 - pwrite() and pwritev() with offset zero returned -ESPIPE
 - the pending response remained intact after the rejected operations
 - a subsequent normal command/response cycle completed normally
 - no KASAN report was produced.

Fixes: 9488585b21be ("tpm: add support for partial reads")
Link: https://lore.kernel.org/all/20260710090217.191289-1-yong010301@gmail.com/
Cc: stable@vger.kernel.org
Signed-off-by: Jaewon Yang <yong010301@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
tpm: fix event_size output in tpm1_binary_bios_measurements_show 2026-07-24T13:49:12+00:00 Thorsten Blum thorsten.blum@linux.dev 2026-06-15T12:02:05+00:00 7dc44bcbcac0fecc053953ffaa86b7b5f5e5f3d0 commit 1a58f6115bfb34eabcc7de8a3a9745b219179781 upstream. Commit 186d124f07da ("tpm_eventlog.c: fix binary_bios_measurements") split the output to write the endian-converted event header first and then the variable-length event data. However, the split was at sizeof(struct tcpa_event) - 1, even though event_data was a zero-length array, and later a flexible array member, both of which already excluded the event data. Therefore, the current code writes the first three bytes of event_size from the endian-converted header and then the last byte from the raw header, which can emit a corrupted event_size on PPC64, where do_endian_conversion() maps to be32_to_cpu(). Split one byte later to write the full endian-converted header first, followed by the variable-length event->event_data. Fixes: 186d124f07da ("tpm_eventlog.c: fix binary_bios_measurements") Cc: stable@vger.kernel.org # v5.10+ Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 1a58f6115bfb34eabcc7de8a3a9745b219179781 upstream.

Commit 186d124f07da ("tpm_eventlog.c: fix binary_bios_measurements")
split the output to write the endian-converted event header first and
then the variable-length event data.

However, the split was at sizeof(struct tcpa_event) - 1, even though
event_data was a zero-length array, and later a flexible array member,
both of which already excluded the event data.

Therefore, the current code writes the first three bytes of event_size
from the endian-converted header and then the last byte from the raw
header, which can emit a corrupted event_size on PPC64, where
do_endian_conversion() maps to be32_to_cpu().

Split one byte later to write the full endian-converted header first,
followed by the variable-length event->event_data.

Fixes: 186d124f07da ("tpm_eventlog.c: fix binary_bios_measurements")
Cc: stable@vger.kernel.org # v5.10+
Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
char: tlclk: fix use-after-free in tlclk_cleanup() 2026-07-24T13:49:01+00:00 James Kim james010kim@gmail.com 2026-05-03T10:11:31+00:00 09d8d2a46a9ec9ff728f3159a174a2ab25dd0f0a [ Upstream commit bbf003b7794d6ad6f939fdd29f1f1bde8ac554c1 ] This patch improves the module cleanup process in the tlclk driver to prevent potential use-after-free and race conditions. Currently, the file_operations structure does not specify the .owner field, which could allow the module to be unloaded while user-space processes are still interacting with the device. Additionally, the tlclk_cleanup() function frees the alarm_events memory before ensuring that blocked processes in the waitqueue are fully awakened and that the switchover_timer has completed. To address these cases, this patch: - Sets '.owner = THIS_MODULE' in tlclk_fops to safely defer module unloading while the device is in use. - Updates tlclk_cleanup() to explicitly wake up all blocked readers (wake_up_all), properly release hardware I/O regions, and safely delete the timer (timer_delete_sync) prior to freeing memory. Fixes: 1a80ba882730 ("[PATCH] Telecom Clock Driver for MPCBL0010 ATCA computer blade") Signed-off-by: James Kim <james010kim@gmail.com> Link: https://patch.msgid.link/20260503101131.64219-1-james010kim@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit bbf003b7794d6ad6f939fdd29f1f1bde8ac554c1 ]

This patch improves the module cleanup process in the tlclk driver to
prevent potential use-after-free and race conditions.

Currently, the file_operations structure does not specify the .owner
field, which could allow the module to be unloaded while user-space
processes are still interacting with the device. Additionally, the
tlclk_cleanup() function frees the alarm_events memory before ensuring
that blocked processes in the waitqueue are fully awakened and that the
switchover_timer has completed.

To address these cases, this patch:
- Sets '.owner = THIS_MODULE' in tlclk_fops to safely defer module
  unloading while the device is in use.
- Updates tlclk_cleanup() to explicitly wake up all blocked readers
  (wake_up_all), properly release hardware I/O regions, and safely
  delete the timer (timer_delete_sync) prior to freeing memory.

Fixes: 1a80ba882730 ("[PATCH] Telecom Clock Driver for MPCBL0010 ATCA computer blade")
Signed-off-by: James Kim <james010kim@gmail.com>
Link: https://patch.msgid.link/20260503101131.64219-1-james010kim@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
hwrng: virtio: clamp device-reported used.len at copy_data() 2026-07-24T13:48:49+00:00 Michael Bommarito michael.bommarito@gmail.com 2026-05-31T14:22:51+00:00 3aa3e89cf80721c8d382b4c1a2b70a0449dad4a5 commit e3046eeada299f917a8ad883af4434bfb86556b1 upstream. random_recv_done() stores the device-reported used.len directly into vi->data_avail. copy_data() then indexes vi->data[] using vi->data_idx (advanced by previous copy_data() calls) and issues a memcpy() without re-validating either value against the posted buffer size sizeof(vi->data) (SMP_CACHE_BYTES bytes, typically 32 or 64). A malicious or buggy virtio-rng backend can set used.len beyond sizeof(vi->data), steering the memcpy() past the end of the inline array into adjacent kmalloc-1k slab bytes. hwrng_fillfn() mixes those bytes into the guest RNG, and guest root can also observe them directly via /dev/hwrng. Concrete impact is inside the guest: - Memory-safety / hardening: any virtio-rng backend that over-reports used.len causes the driver to read past vi->data into unrelated slab contents. hwrng_fillfn() is a kernel thread that runs as soon as the device is probed; no guest userspace interaction is required to first-trigger the OOB. - Cross-boundary leak (confidential-compute threat model): a malicious hypervisor cooperating with a malicious or compromised guest root userspace can use /dev/hwrng as a leak channel for guest-kernel heap data. The host sets a large used.len, guest root reads /dev/hwrng, and the returned bytes contain guest kernel slab contents that were adjacent to vi->data. In practice, confidential-compute guests (SEV-SNP, TDX) usually disable virtio-rng entirely, so this path is narrow, but the fix is still worth carrying because the underlying memory-safety bug contaminates the guest RNG on any host. KASAN confirms the OOB on a 7.1-rc4 guest whose virtio-rng backend has been patched to report used.len = 0x10000: BUG: KASAN: slab-out-of-bounds in virtio_read+0x394/0x5d0 Read of size 64 at addr ffff88800ae0ba20 by task hwrng/52 Call Trace: __asan_memcpy+0x23/0x60 virtio_read+0x394/0x5d0 hwrng_fillfn+0xb2/0x470 kthread+0x2cc/0x3a0 Allocated by task 1: probe_common+0xa5/0x660 virtio_dev_probe+0x549/0xbc0 The buggy address belongs to the object at ffff88800ae0b800 which belongs to the cache kmalloc-1k of size 1024 The buggy address is located 0 bytes to the right of allocated 544-byte region [ffff88800ae0b800, ffff88800ae0ba20) Same class of bug as commit c04db81cd028 ("net/9p: Fix buffer overflow in USB transport layer"), which hardened usb9pfs_rx_complete() against unchecked device-reported length in the USB 9p transport. With the clamp at point of use and array_index_nospec() in place, the same harness boots cleanly: copy_data() returns zero for the bogus report, the device-supplied bytes after data_idx are discarded, and the driver issues a fresh request. Fixes: f7f510ec1957 ("virtio: An entropy device, as suggested by hpa.") Cc: stable@vger.kernel.org Suggested-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael Bommarito <michael.bommarito@gmail.com> Assisted-by: Claude:claude-opus-4-8 Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Message-ID: <20260531142251.2792061-1-michael.bommarito@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit e3046eeada299f917a8ad883af4434bfb86556b1 upstream.

random_recv_done() stores the device-reported used.len directly into
vi->data_avail.  copy_data() then indexes vi->data[] using
vi->data_idx (advanced by previous copy_data() calls) and issues a
memcpy() without re-validating either value against the posted
buffer size sizeof(vi->data) (SMP_CACHE_BYTES bytes, typically 32
or 64).

A malicious or buggy virtio-rng backend can set used.len beyond
sizeof(vi->data), steering the memcpy() past the end of the inline
array into adjacent kmalloc-1k slab bytes.  hwrng_fillfn() mixes
those bytes into the guest RNG, and guest root can also observe
them directly via /dev/hwrng.

Concrete impact is inside the guest:

 - Memory-safety / hardening: any virtio-rng backend that
   over-reports used.len causes the driver to read past vi->data
   into unrelated slab contents.  hwrng_fillfn() is a kernel thread
   that runs as soon as the device is probed; no guest userspace
   interaction is required to first-trigger the OOB.

 - Cross-boundary leak (confidential-compute threat model): a
   malicious hypervisor cooperating with a malicious or compromised
   guest root userspace can use /dev/hwrng as a leak channel for
   guest-kernel heap data.  The host sets a large used.len, guest
   root reads /dev/hwrng, and the returned bytes contain guest
   kernel slab contents that were adjacent to vi->data.  In
   practice, confidential-compute guests (SEV-SNP, TDX) usually
   disable virtio-rng entirely, so this path is narrow, but the
   fix is still worth carrying because the underlying
   memory-safety bug contaminates the guest RNG on any host.

KASAN confirms the OOB on a 7.1-rc4 guest whose virtio-rng backend
has been patched to report used.len = 0x10000:

  BUG: KASAN: slab-out-of-bounds in virtio_read+0x394/0x5d0
  Read of size 64 at addr ffff88800ae0ba20 by task hwrng/52
  Call Trace:
   __asan_memcpy+0x23/0x60
   virtio_read+0x394/0x5d0
   hwrng_fillfn+0xb2/0x470
   kthread+0x2cc/0x3a0
  Allocated by task 1:
   probe_common+0xa5/0x660
   virtio_dev_probe+0x549/0xbc0
  The buggy address belongs to the object at ffff88800ae0b800
   which belongs to the cache kmalloc-1k of size 1024
  The buggy address is located 0 bytes to the right of
   allocated 544-byte region [ffff88800ae0b800, ffff88800ae0ba20)

Same class of bug as commit c04db81cd028 ("net/9p: Fix buffer
overflow in USB transport layer"), which hardened
usb9pfs_rx_complete() against unchecked device-reported length in
the USB 9p transport.

With the clamp at point of use and array_index_nospec() in place,
the same harness boots cleanly: copy_data() returns zero for the
bogus report, the device-supplied bytes after data_idx are
discarded, and the driver issues a fresh request.

Fixes: f7f510ec1957 ("virtio: An entropy device, as suggested by hpa.")
Cc: stable@vger.kernel.org
Suggested-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael Bommarito <michael.bommarito@gmail.com>
Assisted-by: Claude:claude-opus-4-8
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Message-ID: <20260531142251.2792061-1-michael.bommarito@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
agp/amd64: Fix broken error propagation in agp_amd64_probe() 2026-07-04T11:38:37+00:00 Mingyu Wang 25181214217@stu.xidian.edu.cn 2026-05-04T07:48:23+00:00 ce800993af477fc24187349c6a20d3073140b759 commit b08472db93b1ccff84a7adec5779d47f0e9d3a30 upstream. A NULL pointer dereference was observed in the AMD64 AGP driver when running in a virtualized environment (e.g. qemu/kvm) without a physical AMD northbridge. The crash occurs in amd64_fetch_size() when attempting to dereference the pointer returned by node_to_amd_nb(0). The root cause of this crash is broken error propagation in agp_amd64_probe(): When no AMD northbridges are found, cache_nbs() correctly returns -ENODEV. However, the probe function erroneously checks the return value against exactly -1, rather than < 0. As a result, the hardware absence error is masked, allowing the driver to improperly proceed with initialization. It eventually calls agp_add_bridge(), which invokes amd64_fetch_size(). Since the hardware does not exist, node_to_amd_nb(0) returns NULL, leading to a General Protection Fault (GPF) when accessing its ->misc member. Fix the issue by correcting the error check in agp_amd64_probe() to abort properly when cache_nbs() returns any negative error code. This prevents the driver from erroneously proceeding without hardware, thereby avoiding the subsequent NULL pointer dereference at its source. Fixes: a32073bffc65 ("[PATCH] x86_64: Clean and enhance up K8 northbridge access code") Signed-off-by: Mingyu Wang <25181214217@stu.xidian.edu.cn> Signed-off-by: Lukas Wunner <lukas@wunner.de> Reviewed-by: Lukas Wunner <lukas@wunner.de> Cc: stable@vger.kernel.org # v2.6.18+ Link: https://patch.msgid.link/20260504074823.99377-1-w15303746062@163.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit b08472db93b1ccff84a7adec5779d47f0e9d3a30 upstream.

A NULL pointer dereference was observed in the AMD64 AGP driver when
running in a virtualized environment (e.g. qemu/kvm) without a physical
AMD northbridge. The crash occurs in amd64_fetch_size() when attempting
to dereference the pointer returned by node_to_amd_nb(0).

The root cause of this crash is broken error propagation in
agp_amd64_probe(): When no AMD northbridges are found, cache_nbs()
correctly returns -ENODEV. However, the probe function erroneously
checks the return value against exactly -1, rather than < 0.

As a result, the hardware absence error is masked, allowing the driver
to improperly proceed with initialization. It eventually calls
agp_add_bridge(), which invokes amd64_fetch_size(). Since the hardware
does not exist, node_to_amd_nb(0) returns NULL, leading to a General
Protection Fault (GPF) when accessing its ->misc member.

Fix the issue by correcting the error check in agp_amd64_probe() to
abort properly when cache_nbs() returns any negative error code. This
prevents the driver from erroneously proceeding without hardware, thereby
avoiding the subsequent NULL pointer dereference at its source.

Fixes: a32073bffc65 ("[PATCH] x86_64: Clean and enhance up K8 northbridge access code")
Signed-off-by: Mingyu Wang <25181214217@stu.xidian.edu.cn>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Reviewed-by: Lukas Wunner <lukas@wunner.de>
Cc: stable@vger.kernel.org # v2.6.18+
Link: https://patch.msgid.link/20260504074823.99377-1-w15303746062@163.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
use less confusing names for iov_iter direction initializers 2026-06-19T11:21:45+00:00 Al Viro viro@zeniv.linux.org.uk 2026-05-30T14:19:23+00:00 39a5787c9eb3e8c47d121843973ca7225c0f2a35 [ Upstream commit de4eda9de2d957ef2d6a8365a01e26a435e958cb ] READ/WRITE proved to be actively confusing - the meanings are "data destination, as used with read(2)" and "data source, as used with write(2)", but people keep interpreting those as "we read data from it" and "we write data to it", i.e. exactly the wrong way. Call them ITER_DEST and ITER_SOURCE - at least that is harder to misinterpret... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Stable-dep-of: a4f0b001782b ("vsock/virtio: reset connection on receiving queue overflow") Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
[ Upstream commit de4eda9de2d957ef2d6a8365a01e26a435e958cb ]

READ/WRITE proved to be actively confusing - the meanings are
"data destination, as used with read(2)" and "data source, as
used with write(2)", but people keep interpreting those as
"we read data from it" and "we write data to it", i.e. exactly
the wrong way.

Call them ITER_DEST and ITER_SOURCE - at least that is harder
to misinterpret...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Stable-dep-of: a4f0b001782b ("vsock/virtio: reset connection on receiving queue overflow")
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ipmi:ssif: NULL thread on error 2026-06-01T15:29:22+00:00 Corey Minyard corey@minyard.net 2026-05-11T13:19:42+00:00 2e959c3c9eaa1bbe0fcc7c2649335c1094f2e2da commit a8aebe93a4938c0ca1941eeaae821738f869be3d upstream. Cleanup code was checking the thread for NULL, but it was possibly a PTR_ERR() in one spot. Spotted with static analysis. Link: https://sourceforge.net/p/openipmi/mailman/message/59324676/ Fixes: 75c486cb1bca ("ipmi:ssif: Clean up kthread on errors") Cc: <stable@vger.kernel.org> # 91eb7ec72612: ipmi:ssif: Remove unnecessary indention Cc: stable@vger.kernel.org Signed-off-by: Corey Minyard <corey@minyard.net> Signed-off-by: Sasha Levin <sashal@kernel.org> 
commit a8aebe93a4938c0ca1941eeaae821738f869be3d upstream.

Cleanup code was checking the thread for NULL, but it was possibly
a PTR_ERR() in one spot.

Spotted with static analysis.

Link: https://sourceforge.net/p/openipmi/mailman/message/59324676/
Fixes: 75c486cb1bca ("ipmi:ssif: Clean up kthread on errors")
Cc: <stable@vger.kernel.org> # 91eb7ec72612: ipmi:ssif: Remove unnecessary indention
Cc: stable@vger.kernel.org
Signed-off-by: Corey Minyard <corey@minyard.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
ipmi:ssif: Remove unnecessary indention 2026-06-01T15:29:22+00:00 Corey Minyard corey@minyard.net 2026-05-11T13:19:41+00:00 aee2b950a5aca9f517a8bee9189ec70e24e9caf5 commit 91eb7ec7261254b6875909df767185838598e21e upstream. A section was in {} that didn't need to be, move the variable definition to the top and set th eindentino properly. Signed-off-by: Corey Minyard <corey@minyard.net> Signed-off-by: Sasha Levin <sashal@kernel.org> 
commit 91eb7ec7261254b6875909df767185838598e21e upstream.

A section was in {} that didn't need to be, move the variable
definition to the top and set th eindentino properly.

Signed-off-by: Corey Minyard <corey@minyard.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
ipmi:ssif: Clean up kthread on errors 2026-06-01T15:29:22+00:00 Corey Minyard corey@minyard.net 2026-05-11T13:19:40+00:00 549607af66a0efdb41307ba6343eed31de8b133e commit 75c486cb1bcaa1a3ec3a6438498176a3a4998ae4 upstream. If an error occurs after the ssif kthread is created, but before the main IPMI code starts the ssif interface, the ssif kthread will not be stopped. So make sure the kthread is stopped on an error condition if it is running. Fixes: 259307074bfc ("ipmi: Add SMBus interface driver (SSIF)") Reported-by: Li Xiao <<252270051@hdu.edu.cn> Cc: stable@vger.kernel.org Reviewed-by: Li Xiao <252270051@hdu.edu.cn> [Adjusted for stopping flag and complete operation still being present.] Signed-off-by: Corey Minyard <corey@minyard.net> Signed-off-by: Sasha Levin <sashal@kernel.org> 
commit 75c486cb1bcaa1a3ec3a6438498176a3a4998ae4 upstream.

If an error occurs after the ssif kthread is created, but before the
main IPMI code starts the ssif interface, the ssif kthread will not
be stopped.

So make sure the kthread is stopped on an error condition if it is
running.

Fixes: 259307074bfc ("ipmi: Add SMBus interface driver (SSIF)")
Reported-by: Li Xiao <<252270051@hdu.edu.cn>
Cc: stable@vger.kernel.org
Reviewed-by: Li Xiao <252270051@hdu.edu.cn>
[Adjusted for stopping flag and complete operation still being present.]
Signed-off-by: Corey Minyard <corey@minyard.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
ipmi:ssif: Fix a shutdown race 2026-06-01T15:29:22+00:00 Corey Minyard corey@minyard.net 2026-05-11T13:19:39+00:00 c223e808c286382f076b33b7e1e6f06ff2d0add6 It was possible for the SSIF thread to stop and quit before the kthread_stop() call because ssif->stopping was set before the stop. So only exit the SSIF thread is kthread_should_stop() returns true. In the mainstream kernel this was fixed in 6bd0eb6d759b ("ipmi:ssif: Fix a shutdown race"). However, that requires a fix in kernel version 6.1 has a fix to kthread stop to cause interruptible waits to return -ERESTARTSYS on a stop. This has not been backported to older kernels, and that would probably be a bad idea. But it means that the mainstrem kernel fix for this will not work. Instead, wait for kthread_should_stop() to return true before exiting the thread. Signed-off-by: Corey Minyard <cminyard@mvista.com> Signed-off-by: Sasha Levin <sashal@kernel.org> 
It was possible for the SSIF thread to stop and quit before the
kthread_stop() call because ssif->stopping was set before the
stop.  So only exit the SSIF thread is kthread_should_stop()
returns true.

In the mainstream kernel this was fixed in 6bd0eb6d759b ("ipmi:ssif:
Fix a shutdown race").  However, that requires a fix in kernel
version 6.1 has a fix to kthread stop to cause interruptible waits
to return -ERESTARTSYS on a stop.  This has not been backported to
older kernels, and that would probably be a bad idea.  But it means
that the mainstrem kernel fix for this will not work.

Instead, wait for kthread_should_stop() to return true before exiting
the thread.

Signed-off-by: Corey Minyard <cminyard@mvista.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>