Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
tracing: Do not register unsupported perf events
Synthetic events currently do not have a function to register perf events.
This leads to calling the tracepoint register functions with a NULL
function pointer which triggers:
------------[ cut here ]------------
WARNING: kernel/tracepoint.c:175 at tracepoint_add_func+0x357/0x370, CPU#2: perf/2272
Modules linked in: kvm_intel kvm irqbypass
CPU: 2 UID: 0 PID: 2272 Comm: perf Not tainted 6.18.0-ftest-11964-ge022764176fc-dirty #323 PREEMPTLAZY
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.17.0-debian-1.17.0-1 04/01/2014
RIP: 0010:tracepoint_add_func+0x357/0x370
Code: 28 9c e8 4c 0b f5 ff eb 0f 4c 89 f7 48 c7 c6 80 4d 28 9c e8 ab 89 f4 ff 31 c0 5b 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc cc <0f> 0b 49 c7 c6 ea ff ff ff e9 ee fe ff ff 0f 0b e9 f9 fe ff ff 0f
RSP: 0018:ffffabc0c44d3c40 EFLAGS: 00010246
RAX: 0000000000000001 RBX: ffff9380aa9e4060 RCX: 0000000000000000
RDX: 000000000000000a RSI: ffffffff9e1d4a98 RDI: ffff937fcf5fd6c8
RBP: 0000000000000001 R08: 0000000000000007 R09: ffff937fcf5fc780
R10: 0000000000000003 R11: ffffffff9c193910 R12: 000000000000000a
R13: ffffffff9e1e5888 R14: 0000000000000000 R15: ffffabc0c44d3c78
FS: 00007f6202f5f340(0000) GS:ffff93819f00f000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055d3162281a8 CR3: 0000000106a56003 CR4: 0000000000172ef0
Call Trace:
<TASK>
tracepoint_probe_register+0x5d/0x90
synth_event_reg+0x3c/0x60
perf_trace_event_init+0x204/0x340
perf_trace_init+0x85/0xd0
perf_tp_event_init+0x2e/0x50
perf_try_init_event+0x6f/0x230
? perf_event_alloc+0x4bb/0xdc0
perf_event_alloc+0x65a/0xdc0
__se_sys_perf_event_open+0x290/0x9f0
do_syscall_64+0x93/0x7b0
? entry_SYSCALL_64_after_hwframe+0x76/0x7e
? trace_hardirqs_off+0x53/0xc0
entry_SYSCALL_64_after_hwframe+0x76/0x7e
Instead, have the code return -ENODEV, which doesn't warn and has perf
error out with:
# perf record -e synthetic:futex_wait
Error:
The sys_perf_event_open() syscall returned with 19 (No such device) for event (synthetic:futex_wait).
"dmesg | grep -i perf" may provide additional information.
Ideally perf should support synthetic events, but for now just fix the
warning. The support can come later.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-01-14
In the Linux kernel, the following vulnerability has been resolved:
mptcp: avoid deadlock on fallback while reinjecting
Jakub reported an MPTCP deadlock at fallback time:
WARNING: possible recursive locking detected
6.18.0-rc7-virtme #1 Not tainted
--------------------------------------------
mptcp_connect/20858 is trying to acquire lock:
ff1100001da18b60 (&msk->fallback_lock){+.-.}-{3:3}, at: __mptcp_try_fallback+0xd8/0x280
but task is already holding lock:
ff1100001da18b60 (&msk->fallback_lock){+.-.}-{3:3}, at: __mptcp_retrans+0x352/0xaa0
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0
----
lock(&msk->fallback_lock);
lock(&msk->fallback_lock);
*** DEADLOCK ***
May be due to missing lock nesting notation
3 locks held by mptcp_connect/20858:
#0: ff1100001da18290 (sk_lock-AF_INET){+.+.}-{0:0}, at: mptcp_sendmsg+0x114/0x1bc0
#1: ff1100001db40fd0 (k-sk_lock-AF_INET#2){+.+.}-{0:0}, at: __mptcp_retrans+0x2cb/0xaa0
#2: ff1100001da18b60 (&msk->fallback_lock){+.-.}-{3:3}, at: __mptcp_retrans+0x352/0xaa0
stack backtrace:
CPU: 0 UID: 0 PID: 20858 Comm: mptcp_connect Not tainted 6.18.0-rc7-virtme #1 PREEMPT(full)
Hardware name: Bochs, BIOS Bochs 01/01/2011
Call Trace:
<TASK>
dump_stack_lvl+0x6f/0xa0
print_deadlock_bug.cold+0xc0/0xcd
validate_chain+0x2ff/0x5f0
__lock_acquire+0x34c/0x740
lock_acquire.part.0+0xbc/0x260
_raw_spin_lock_bh+0x38/0x50
__mptcp_try_fallback+0xd8/0x280
mptcp_sendmsg_frag+0x16c2/0x3050
__mptcp_retrans+0x421/0xaa0
mptcp_release_cb+0x5aa/0xa70
release_sock+0xab/0x1d0
mptcp_sendmsg+0xd5b/0x1bc0
sock_write_iter+0x281/0x4d0
new_sync_write+0x3c5/0x6f0
vfs_write+0x65e/0xbb0
ksys_write+0x17e/0x200
do_syscall_64+0xbb/0xfd0
entry_SYSCALL_64_after_hwframe+0x4b/0x53
RIP: 0033:0x7fa5627cbc5e
Code: 4d 89 d8 e8 14 bd 00 00 4c 8b 5d f8 41 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 11 c9 c3 0f 1f 80 00 00 00 00 48 8b 45 10 0f 05 <c9> c3 83 e2 39 83 fa 08 75 e7 e8 13 ff ff ff 0f 1f 00 f3 0f 1e fa
RSP: 002b:00007fff1fe14700 EFLAGS: 00000202 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 00007fa5627cbc5e
RDX: 0000000000001f9c RSI: 00007fff1fe16984 RDI: 0000000000000005
RBP: 00007fff1fe14710 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 00007fff1fe16920
R13: 0000000000002000 R14: 0000000000001f9c R15: 0000000000001f9c
The packet scheduler could attempt a reinjection after receiving an
MP_FAIL and before the infinite map has been transmitted, causing a
deadlock since MPTCP needs to do the reinjection atomically from WRT
fallback.
Address the issue explicitly avoiding the reinjection in the critical
scenario. Note that this is the only fallback critical section that
could potentially send packets and hit the double-lock.
CVSS Score
5.5
EPSS Score
0.0
Published
2026-01-14
In the Linux kernel, the following vulnerability has been resolved:
wifi: mac80211: Discard Beacon frames to non-broadcast address
Beacon frames are required to be sent to the broadcast address, see IEEE
Std 802.11-2020, 11.1.3.1 ("The Address 1 field of the Beacon .. frame
shall be set to the broadcast address"). A unicast Beacon frame might be
used as a targeted attack to get one of the associated STAs to do
something (e.g., using CSA to move it to another channel). As such, it
is better have strict filtering for this on the received side and
discard all Beacon frames that are sent to an unexpected address.
This is even more important for cases where beacon protection is used.
The current implementation in mac80211 is correctly discarding unicast
Beacon frames if the Protected Frame bit in the Frame Control field is
set to 0. However, if that bit is set to 1, the logic used for checking
for configured BIGTK(s) does not actually work. If the driver does not
have logic for dropping unicast Beacon frames with Protected Frame bit
1, these frames would be accepted in mac80211 processing as valid Beacon
frames even though they are not protected. This would allow beacon
protection to be bypassed. While the logic for checking beacon
protection could be extended to cover this corner case, a more generic
check for discard all Beacon frames based on A1=unicast address covers
this without needing additional changes.
Address all these issues by dropping received Beacon frames if they are
sent to a non-broadcast address.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-01-14
In the Linux kernel, the following vulnerability has been resolved:
erspan: Initialize options_len before referencing options.
The struct ip_tunnel_info has a flexible array member named
options that is protected by a counted_by(options_len)
attribute.
The compiler will use this information to enforce runtime bounds
checking deployed by FORTIFY_SOURCE string helpers.
As laid out in the GCC documentation, the counter must be
initialized before the first reference to the flexible array
member.
After scanning through the files that use struct ip_tunnel_info
and also refer to options or options_len, it appears the normal
case is to use the ip_tunnel_info_opts_set() helper.
Said helper would initialize options_len properly before copying
data into options, however in the GRE ERSPAN code a partial
update is done, preventing the use of the helper function.
Before this change the handling of ERSPAN traffic in GRE tunnels
would cause a kernel panic when the kernel is compiled with
GCC 15+ and having FORTIFY_SOURCE configured:
memcpy: detected buffer overflow: 4 byte write of buffer size 0
Call Trace:
<IRQ>
__fortify_panic+0xd/0xf
erspan_rcv.cold+0x68/0x83
? ip_route_input_slow+0x816/0x9d0
gre_rcv+0x1b2/0x1c0
gre_rcv+0x8e/0x100
? raw_v4_input+0x2a0/0x2b0
ip_protocol_deliver_rcu+0x1ea/0x210
ip_local_deliver_finish+0x86/0x110
ip_local_deliver+0x65/0x110
? ip_rcv_finish_core+0xd6/0x360
ip_rcv+0x186/0x1a0
Reported-at: https://launchpad.net/bugs/2129580
CVSS Score
5.5
EPSS Score
0.0
Published
2026-01-14
In the Linux kernel, the following vulnerability has been resolved:
LoongArch: BPF: Sign extend kfunc call arguments
The kfunc calls are native calls so they should follow LoongArch calling
conventions. Sign extend its arguments properly to avoid kernel panic.
This is done by adding a new emit_abi_ext() helper. The emit_abi_ext()
helper performs extension in place meaning a value already store in the
target register (Note: this is different from the existing sign_extend()
helper and thus we can't reuse it).
CVSS Score
5.5
EPSS Score
0.0
Published
2026-01-14
In the Linux kernel, the following vulnerability has been resolved:
drm/i915/gem: Zero-initialize the eb.vma array in i915_gem_do_execbuffer
Initialize the eb.vma array with values of 0 when the eb structure is
first set up. In particular, this sets the eb->vma[i].vma pointers to
NULL, simplifying cleanup and getting rid of the bug described below.
During the execution of eb_lookup_vmas(), the eb->vma array is
successively filled up with struct eb_vma objects. This process includes
calling eb_add_vma(), which might fail; however, even in the event of
failure, eb->vma[i].vma is set for the currently processed buffer.
If eb_add_vma() fails, eb_lookup_vmas() returns with an error, which
prompts a call to eb_release_vmas() to clean up the mess. Since
eb_lookup_vmas() might fail during processing any (possibly not first)
buffer, eb_release_vmas() checks whether a buffer's vma is NULL to know
at what point did the lookup function fail.
In eb_lookup_vmas(), eb->vma[i].vma is set to NULL if either the helper
function eb_lookup_vma() or eb_validate_vma() fails. eb->vma[i+1].vma is
set to NULL in case i915_gem_object_userptr_submit_init() fails; the
current one needs to be cleaned up by eb_release_vmas() at this point,
so the next one is set. If eb_add_vma() fails, neither the current nor
the next vma is set to NULL, which is a source of a NULL deref bug
described in the issue linked in the Closes tag.
When entering eb_lookup_vmas(), the vma pointers are set to the slab
poison value, instead of NULL. This doesn't matter for the actual
lookup, since it gets overwritten anyway, however the eb_release_vmas()
function only recognizes NULL as the stopping value, hence the pointers
are being set to NULL as they go in case of intermediate failure. This
patch changes the approach to filling them all with NULL at the start
instead, rather than handling that manually during failure.
(cherry picked from commit 08889b706d4f0b8d2352b7ca29c2d8df4d0787cd)
CVSS Score
5.5
EPSS Score
0.0
Published
2026-01-14
In the Linux kernel, the following vulnerability has been resolved:
crypto: seqiv - Do not use req->iv after crypto_aead_encrypt
As soon as crypto_aead_encrypt is called, the underlying request
may be freed by an asynchronous completion. Thus dereferencing
req->iv after it returns is invalid.
Instead of checking req->iv against info, create a new variable
unaligned_info and use it for that purpose instead.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-01-14
In the Linux kernel, the following vulnerability has been resolved:
smc91x: fix broken irq-context in PREEMPT_RT
When smc91x.c is built with PREEMPT_RT, the following splat occurs
in FVP_RevC:
[ 13.055000] smc91x LNRO0003:00 eth0: link up, 10Mbps, half-duplex, lpa 0x0000
[ 13.062137] BUG: workqueue leaked atomic, lock or RCU: kworker/2:1[106]
[ 13.062137] preempt=0x00000000 lock=0->0 RCU=0->1 workfn=mld_ifc_work
[ 13.062266] C
** replaying previous printk message **
[ 13.062266] CPU: 2 UID: 0 PID: 106 Comm: kworker/2:1 Not tainted 6.18.0-dirty #179 PREEMPT_{RT,(full)}
[ 13.062353] Hardware name: , BIOS
[ 13.062382] Workqueue: mld mld_ifc_work
[ 13.062469] Call trace:
[ 13.062494] show_stack+0x24/0x40 (C)
[ 13.062602] __dump_stack+0x28/0x48
[ 13.062710] dump_stack_lvl+0x7c/0xb0
[ 13.062818] dump_stack+0x18/0x34
[ 13.062926] process_scheduled_works+0x294/0x450
[ 13.063043] worker_thread+0x260/0x3d8
[ 13.063124] kthread+0x1c4/0x228
[ 13.063235] ret_from_fork+0x10/0x20
This happens because smc_special_trylock() disables IRQs even on PREEMPT_RT,
but smc_special_unlock() does not restore IRQs on PREEMPT_RT.
The reason is that smc_special_unlock() calls spin_unlock_irqrestore(),
and rcu_read_unlock_bh() in __dev_queue_xmit() cannot invoke
rcu_read_unlock() through __local_bh_enable_ip() when current->softirq_disable_cnt becomes zero.
To address this issue, replace smc_special_trylock() with spin_trylock_irqsave().
CVSS Score
5.5
EPSS Score
0.001
Published
2026-01-14
In the Linux kernel, the following vulnerability has been resolved:
via_wdt: fix critical boot hang due to unnamed resource allocation
The VIA watchdog driver uses allocate_resource() to reserve a MMIO
region for the watchdog control register. However, the allocated
resource was not given a name, which causes the kernel resource tree
to contain an entry marked as "<BAD>" under /proc/iomem on x86
platforms.
During boot, this unnamed resource can lead to a critical hang because
subsequent resource lookups and conflict checks fail to handle the
invalid entry properly.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-01-14
In the Linux kernel, the following vulnerability has been resolved:
um: init cpu_tasks[] earlier
This is currently done in uml_finishsetup(), but e.g. with
KCOV enabled we'll crash because some init code can call
into e.g. memparse(), which has coverage annotations, and
then the checks in check_kcov_mode() crash because current
is NULL.
Simply initialize the cpu_tasks[] array statically, which
fixes the crash. For the later SMP work, it seems to have
not really caused any problems yet, but initialize all of
the entries anyway.
CVSS Score
5.5
EPSS Score
0.0
Published
2026-01-14