Linux: >> Linux Kernel >> 6.12.95 Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
f2fs: fix fsck inconsistency caused by incorrect nat_entry flag usage
f2fs_need_dentry_mark() reads nat_entry flags without mutual exclusion
with the checkpoint path, which can result in an incorrect inode block
marking state. The scenario is as follows:
create & write & fsync 'file A' write checkpoint
- f2fs_do_sync_file // inline inode
- f2fs_write_inode // inode folio is dirty
- f2fs_write_checkpoint
- f2fs_flush_merged_writes
- f2fs_sync_node_pages
- f2fs_fsync_node_pages // no dirty node
- f2fs_need_inode_block_update // return true
- f2fs_fsync_node_pages // inode dirtied
- f2fs_need_dentry_mark //return true
- f2fs_flush_nat_entries
- f2fs_write_checkpoint end
- __write_node_folio // inode with DENT_BIT_SHIFT set
SPO, "fsck --dry-run" find inode has already checkpointed but still
with DENT_BIT_SHIFT set
The state observed by f2fs_need_dentry_mark() can differ from the state
observed in __write_node_folio() after acquiring sbi->node_write. The
root cause is that the semantics of IS_CHECKPOINTED and
HAS_FSYNCED_INODE are only guaranteed after the checkpoint write has
fully completed.
This patch moves set_dentry_mark() into __write_node_folio() and
protects it with the sbi->node_write lock.
CVSS Score
7.1
EPSS Score
0.001
Published
2026-07-19
In the Linux kernel, the following vulnerability has been resolved:
vsock/virtio: fix zerocopy completion for multi-skb sends
When a large message is fragmented into multiple skbs, the zerocopy
uarg is only allocated and attached to the last skb in the loop.
Non-final skbs carry pinned user pages with no completion tracking,
so the kernel has no way to notify userspace when those pages are safe
to reuse. If the loop breaks early the uarg is never allocated at all,
leaking pinned pages with no completion notification.
Fix this by following the approach used by TCP: allocate the zerocopy
uarg (if not provided by the caller) before the send loop and attach
it to every skb via skb_zcopy_set(), which takes a reference per skb.
Each skb's completion properly decrements the refcount, and the
notification only fires after the last skb is freed.
On failure, if no data was sent, the uarg is cleanly aborted via
net_zcopy_put_abort().
This issue was initially discovered by sashiko while reviewing commit
1cb36e252211 ("vsock/virtio: fix MSG_ZEROCOPY pinned-pages accounting")
but was pre-existing.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-07-13
In the Linux kernel, the following vulnerability has been resolved:
drm/amd/display: Fix out-of-bounds read in dp_get_eq_aux_rd_interval()
[Why & How]
The aux_rd_interval array in struct dc_lttpr_caps is declared with
MAX_REPEATER_CNT - 1 (7) elements, indexed 0..6. However, the offset
parameter passed to dp_get_eq_aux_rd_interval() can be as large as
MAX_REPEATER_CNT (8) when a sink reports 8 LTTPR repeaters via DPCD.
This leads to an out-of-bounds read of aux_rd_interval[7] when offset
is 8.
Fix this by growing aux_rd_interval to MAX_REPEATER_CNT elements to
accommodate the full range of valid repeater counts defined by the DP
spec.
(cherry picked from commit a55a458a8df37a65ffda5cf721d554a8f74f6b04)
CVSS Score
7.1
EPSS Score
0.001
Published
2026-07-01
In the Linux kernel, the following vulnerability has been resolved:
io_uring/napi: cap busy_poll_to 10 msec
Currently there's no cap on the maximum amount of time that napi is
allowed to poll if no events are found, which can lead to kernel
complaints on a task being stuck as there's no conditional rescheduling
done within that loop.
Just cap it to 10 msec in total, that's already way above any kind of
sane value that will reap any benefits, yet low enough that it's
nowhere near being able to trigger preemption complaints.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-06-26
In the Linux kernel, the following vulnerability has been resolved:
drm/amd/display: Avoid NULL dereference in dc_dmub_srv error paths
In dc_dmub_srv_log_diagnostic_data() and
dc_dmub_srv_enable_dpia_trace().
Both functions check:
if (!dc_dmub_srv || !dc_dmub_srv->dmub)
and then call DC_LOG_ERROR() inside that block.
DC_LOG_ERROR() uses dc_dmub_srv->ctx internally. So if
dc_dmub_srv is NULL, the logging itself can dereference a
NULL pointer and cause a crash.
Fix this by splitting the checks.
First check if dc_dmub_srv is NULL and return immediately.
Then check dc_dmub_srv->dmub and log the error only when
dc_dmub_srv is valid.
Fixes the below:
../display/dc/dc_dmub_srv.c:962 dc_dmub_srv_log_diagnostic_data() error: we previously assumed 'dc_dmub_srv' could be null (see line 961)
../display/dc/dc_dmub_srv.c:1167 dc_dmub_srv_enable_dpia_trace() error: we previously assumed 'dc_dmub_srv' could be null (see line 1166)
CVSS Score
5.5
EPSS Score
0.001
Published
2026-06-26
In the Linux kernel, the following vulnerability has been resolved:
net: phonet: do not BUG_ON() in pn_socket_autobind() on failed bind
syzbot reported a kernel BUG triggered from pn_socket_sendmsg() via
pn_socket_autobind():
kernel BUG at net/phonet/socket.c:213!
RIP: 0010:pn_socket_autobind net/phonet/socket.c:213 [inline]
RIP: 0010:pn_socket_sendmsg+0x240/0x250 net/phonet/socket.c:421
Call Trace:
sock_sendmsg_nosec+0x112/0x150 net/socket.c:797
__sock_sendmsg net/socket.c:812 [inline]
__sys_sendto+0x402/0x590 net/socket.c:2280
...
pn_socket_autobind() calls pn_socket_bind() with port 0 and, on
-EINVAL, assumes the socket was already bound and asserts that the
port is non-zero:
err = pn_socket_bind(sock, ..., sizeof(struct sockaddr_pn));
if (err != -EINVAL)
return err;
BUG_ON(!pn_port(pn_sk(sock->sk)->sobject));
return 0; /* socket was already bound */
However pn_socket_bind() also returns -EINVAL when sk->sk_state is not
TCP_CLOSE, even when the socket has never been bound and pn_port() is
still 0. In that case the BUG_ON() fires and panics the kernel from a
user-triggerable path.
Treat the "bind returned -EINVAL but pn_port() is still 0" case as a
regular error and propagate -EINVAL to the caller instead of crashing.
Existing callers already translate a non-zero return from
pn_socket_autobind() into -ENOBUFS/-EAGAIN, so returning -EINVAL here
only changes behaviour from panic to a normal errno.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-06-26
In the Linux kernel, the following vulnerability has been resolved:
net: mana: Guard mana_remove against double invocation
If PM resume fails (e.g., mana_attach() returns an error), mana_probe()
calls mana_remove(), which tears down the device and sets
gd->gdma_context = NULL and gd->driver_data = NULL.
However, a failed resume callback does not automatically unbind the
driver. When the device is eventually unbound, mana_remove() is invoked
a second time. Without a NULL check, it dereferences gc->dev with
gc == NULL, causing a kernel panic.
Add an early return if gdma_context or driver_data is NULL so the second
invocation is harmless. Move the dev = gc->dev assignment after the
guard so it cannot dereference NULL.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-06-26
In the Linux kernel, the following vulnerability has been resolved:
drm/amd/display: Wrap DCN32 phantom-plane allocation in DC_RUN_WITH_PREEMPTION_ENABLED
[Why]
dcn32_validate_bandwidth() wraps dcn32_internal_validate_bw() with
DC_FP_START()/DC_FP_END(). In x86 non-RT, DC_FP_START takes fpregs_lock(),
which disables local softirqs.
The DML1 path through dcn32_enable_phantom_plane() calls kvzalloc() to
allocate ~335 KiB for dc_plane_state. This triggers the vmalloc path,
which calls BUG_ON(in_interrupt()) because it's invoked within the
FPU-enabled (softirq disabled) region, leading to a kernel crash.
[How]
Wrap the dc_state_create_phantom_plane() call with the
DC_RUN_WITH_PREEMPTION_ENABLED() macro to allow preemption during
this memory allocation.
(cherry picked from commit 885ccbef7b94a8b38f69c4211c679021aa27ad11)
CVSS Score
5.5
EPSS Score
0.001
Published
2026-06-26
In the Linux kernel, the following vulnerability has been resolved:
btrfs: only release the dirty pages io tree after successful writes
[WARNING]
With extra warning on dirty extent buffers at umount (aka, the next
patch in the series), test case generic/388 can trigger the following
warning about dirty extent buffers at unmount time:
BTRFS critical (device dm-2 state E): emergency shutdown
BTRFS error (device dm-2 state E): error while writing out transaction: -30
BTRFS warning (device dm-2 state E): Skipping commit of aborted transaction.
BTRFS error (device dm-2 state EA): Transaction 9 aborted (error -30)
BTRFS: error (device dm-2 state EA) in cleanup_transaction:2068: errno=-30 Readonly filesystem
BTRFS info (device dm-2 state EA): forced readonly
BTRFS info (device dm-2 state EA): last unmount of filesystem 4fbf2e15-f941-49a0-bc7c-716315d2777c
------------[ cut here ]------------
WARNING: disk-io.c:3311 at invalidate_and_check_btree_folios+0xfd/0x1ca [btrfs], CPU#8: umount/914368
CPU: 8 UID: 0 PID: 914368 Comm: umount Tainted: G OE 7.1.0-rc1-custom+ #372 PREEMPT(full) 2de38db8d1deae71fde295430a0ff3ab98ccf596
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS unknown 02/02/2022
RIP: 0010:invalidate_and_check_btree_folios+0xfd/0x1ca [btrfs]
Call Trace:
<TASK>
close_ctree+0x52e/0x574 [btrfs d2f0b1cd330d1287e7a9919d112eadfc0e914efd]
generic_shutdown_super+0x89/0x1a0
kill_anon_super+0x16/0x40
btrfs_kill_super+0x16/0x20 [btrfs d2f0b1cd330d1287e7a9919d112eadfc0e914efd]
deactivate_locked_super+0x2d/0xb0
cleanup_mnt+0xdc/0x140
task_work_run+0x5a/0xa0
exit_to_user_mode_loop+0x123/0x4b0
do_syscall_64+0x243/0x7c0
entry_SYSCALL_64_after_hwframe+0x4b/0x53
</TASK>
---[ end trace 0000000000000000 ]---
BTRFS warning (device dm-2 state EA): unable to release extent buffer 30539776 owner 9 gen 9 refs 2 flags 0x7
BTRFS warning (device dm-2 state EA): unable to release extent buffer 30621696 owner 257 gen 9 refs 2 flags 0x7
BTRFS warning (device dm-2 state EA): unable to release extent buffer 30638080 owner 258 gen 9 refs 2 flags 0x7
BTRFS warning (device dm-2 state EA): unable to release extent buffer 30654464 owner 7 gen 9 refs 2 flags 0x7
BTRFS warning (device dm-2 state EA): unable to release extent buffer 30703616 owner 2 gen 9 refs 2 flags 0x7
BTRFS warning (device dm-2 state EA): unable to release extent buffer 30720000 owner 10 gen 9 refs 2 flags 0x7
BTRFS warning (device dm-2 state EA): unable to release extent buffer 30736384 owner 4 gen 9 refs 2 flags 0x7
BTRFS warning (device dm-2 state EA): unable to release extent buffer 30752768 owner 11 gen 9 refs 2 flags 0x7
I'm using a stripped down version, which seems to trigger the warning
more reliably:
_fsstress_pid=""
workload()
{
dmesg -C
mkfs.btrfs -f -K $dev > /dev/null
echo 1 > /sys/kernel/debug/clear_warn_once
mount $dev $mnt
$fsstress -w -n 1024 -p 4 -d $mnt &
_fsstress_pid=$!
sleep 0
$godown $mnt
pkill --echo -PIPE fsstress > /dev/null
wait $_fsstress_pid
unset _fsstress_pid
umount $mnt
if dmesg | grep -q "WARNING"; then
fail
fi
}
for (( i = 0; i < $runtime; i++ )); do
echo "=== $i/$runtime ==="
workload
done
[CAUSE]
Inside btrfs_write_and_wait_transaction(), we first try to write all
dirty ebs, then wait for them to finish.
After that we call btrfs_extent_io_tree_release() to free all
extent states from dirty_pages io tree.
However if we hit an error from btrfs_write_marked_extent(), then we
still call btrfs_extent_io_tree_release() to clear that dirty_pages io
tree, which may contain dirty records that we haven't yet submitted.
Furthermore, the later transaction cleanup path will utilize that
dirty_pages io tree to properly cleanup those dirty ebs, but since it's
already empty, no dirty ebs are properly cleaned up, thus will later
trigger the warnings inside invalidate_btree_folios().
---truncated---
CVSS Score
7.5
EPSS Score
0.004
Published
2026-06-26
In the Linux kernel, the following vulnerability has been resolved:
iommu/vt-d: Avoid NULL pointer dereference or refcount corruption
Commit 60f030f7418d ("iommu/vt-d: Avoid use of NULL after WARN_ON_ONCE")
fixed a NULL pointer dereference in an unlikely situation partly.
If dev_pasid is not found in the dev_pasids list, it remains NULL.
However, the teardown operations are executed unconditionally, this lead
to a NULL pointer dereference or refcount corruption.
If the domain was never attached to this IOMMU, info will be NULL, which
would cause an immediate dereference when checking --info->refcnt.
Even if info is not NULL, decrementing the refcount without having removed
a valid PASID might unbalance the count. This could lead to premature
dropping of the refcount to 0, potentially causing a use-after-free for the
remaining active devices sharing the domain.
Fix it by returning early if dev_pasid is NULL, before executing the
teardown operations.
Issue found by AI review and suggested by Kevin Tian.
https://sashiko.dev/#/patchset/20260421031347.1408890-1-zhenzhong.duan%40intel.com
CVSS Score
8.8
EPSS Score
0.001
Published
2026-06-26