Linux: >> Linux Kernel >> 6.1.16 Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
ublk: fail to recover device if queue setup is interrupted
In ublk_ctrl_end_recovery(), if wait_for_completion_interruptible() is
interrupted by signal, queues aren't setup successfully yet, so we
have to fail UBLK_CMD_END_USER_RECOVERY, otherwise kernel oops can be
triggered.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-15
In the Linux kernel, the following vulnerability has been resolved:
KVM: nSVM: Load L1's TSC multiplier based on L1 state, not L2 state
When emulating nested VM-Exit, load L1's TSC multiplier if L1's desired
ratio doesn't match the current ratio, not if the ratio L1 is using for
L2 diverges from the default. Functionally, the end result is the same
as KVM will run L2 with L1's multiplier if L2's multiplier is the default,
i.e. checking that L1's multiplier is loaded is equivalent to checking if
L2 has a non-default multiplier.
However, the assertion that TSC scaling is exposed to L1 is flawed, as
userspace can trigger the WARN at will by writing the MSR and then
updating guest CPUID to hide the feature (modifying guest CPUID is
allowed anytime before KVM_RUN). E.g. hacking KVM's state_test
selftest to do
vcpu_set_msr(vcpu, MSR_AMD64_TSC_RATIO, 0);
vcpu_clear_cpuid_feature(vcpu, X86_FEATURE_TSCRATEMSR);
after restoring state in a new VM+vCPU yields an endless supply of:
------------[ cut here ]------------
WARNING: CPU: 10 PID: 206939 at arch/x86/kvm/svm/nested.c:1105
nested_svm_vmexit+0x6af/0x720 [kvm_amd]
Call Trace:
nested_svm_exit_handled+0x102/0x1f0 [kvm_amd]
svm_handle_exit+0xb9/0x180 [kvm_amd]
kvm_arch_vcpu_ioctl_run+0x1eab/0x2570 [kvm]
kvm_vcpu_ioctl+0x4c9/0x5b0 [kvm]
? trace_hardirqs_off+0x4d/0xa0
__se_sys_ioctl+0x7a/0xc0
__x64_sys_ioctl+0x21/0x30
do_syscall_64+0x41/0x90
entry_SYSCALL_64_after_hwframe+0x63/0xcd
Unlike the nested VMRUN path, hoisting the svm->tsc_scaling_enabled check
into the if-statement is wrong as KVM needs to ensure L1's multiplier is
loaded in the above scenario. Alternatively, the WARN_ON() could simply
be deleted, but that would make KVM's behavior even more subtle, e.g. it's
not immediately obvious why it's safe to write MSR_AMD64_TSC_RATIO when
checking only tsc_ratio_msr.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-15
In the Linux kernel, the following vulnerability has been resolved:
wifi: mac80211_hwsim: Fix possible NULL dereference
In a call to mac80211_hwsim_select_tx_link() the sta pointer might
be NULL, thus need to check that it is not NULL before accessing it.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-15
In the Linux kernel, the following vulnerability has been resolved:
md/raid5-cache: fix null-ptr-deref for r5l_flush_stripe_to_raid()
r5l_flush_stripe_to_raid() will check if the list 'flushing_ios' is
empty, and then submit 'flush_bio', however, r5l_log_flush_endio()
is clearing the list first and then clear the bio, which will cause
null-ptr-deref:
T1: submit flush io
raid5d
handle_active_stripes
r5l_flush_stripe_to_raid
// list is empty
// add 'io_end_ios' to the list
bio_init
submit_bio
// io1
T2: io1 is done
r5l_log_flush_endio
list_splice_tail_init
// clear the list
T3: submit new flush io
...
r5l_flush_stripe_to_raid
// list is empty
// add 'io_end_ios' to the list
bio_init
bio_uninit
// clear bio->bi_blkg
submit_bio
// null-ptr-deref
Fix this problem by clearing bio before clearing the list in
r5l_log_flush_endio().
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-15
In the Linux kernel, the following vulnerability has been resolved:
wifi: brcmfmac: slab-out-of-bounds read in brcmf_get_assoc_ies()
Fix a slab-out-of-bounds read that occurs in kmemdup() called from
brcmf_get_assoc_ies().
The bug could occur when assoc_info->req_len, data from a URB provided
by a USB device, is bigger than the size of buffer which is defined as
WL_EXTRA_BUF_MAX.
Add the size check for req_len/resp_len of assoc_info.
Found by a modified version of syzkaller.
[ 46.592467][ T7] ==================================================================
[ 46.594687][ T7] BUG: KASAN: slab-out-of-bounds in kmemdup+0x3e/0x50
[ 46.596572][ T7] Read of size 3014656 at addr ffff888019442000 by task kworker/0:1/7
[ 46.598575][ T7]
[ 46.599157][ T7] CPU: 0 PID: 7 Comm: kworker/0:1 Tainted: G O 5.14.0+ #145
[ 46.601333][ T7] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.1-0-ga5cab58e9a3f-prebuilt.qemu.org 04/01/2014
[ 46.604360][ T7] Workqueue: events brcmf_fweh_event_worker
[ 46.605943][ T7] Call Trace:
[ 46.606584][ T7] dump_stack_lvl+0x8e/0xd1
[ 46.607446][ T7] print_address_description.constprop.0.cold+0x93/0x334
[ 46.608610][ T7] ? kmemdup+0x3e/0x50
[ 46.609341][ T7] kasan_report.cold+0x79/0xd5
[ 46.610151][ T7] ? kmemdup+0x3e/0x50
[ 46.610796][ T7] kasan_check_range+0x14e/0x1b0
[ 46.611691][ T7] memcpy+0x20/0x60
[ 46.612323][ T7] kmemdup+0x3e/0x50
[ 46.612987][ T7] brcmf_get_assoc_ies+0x967/0xf60
[ 46.613904][ T7] ? brcmf_notify_vif_event+0x3d0/0x3d0
[ 46.614831][ T7] ? lock_chain_count+0x20/0x20
[ 46.615683][ T7] ? mark_lock.part.0+0xfc/0x2770
[ 46.616552][ T7] ? lock_chain_count+0x20/0x20
[ 46.617409][ T7] ? mark_lock.part.0+0xfc/0x2770
[ 46.618244][ T7] ? lock_chain_count+0x20/0x20
[ 46.619024][ T7] brcmf_bss_connect_done.constprop.0+0x241/0x2e0
[ 46.620019][ T7] ? brcmf_parse_configure_security.isra.0+0x2a0/0x2a0
[ 46.620818][ T7] ? __lock_acquire+0x181f/0x5790
[ 46.621462][ T7] brcmf_notify_connect_status+0x448/0x1950
[ 46.622134][ T7] ? rcu_read_lock_bh_held+0xb0/0xb0
[ 46.622736][ T7] ? brcmf_cfg80211_join_ibss+0x7b0/0x7b0
[ 46.623390][ T7] ? find_held_lock+0x2d/0x110
[ 46.623962][ T7] ? brcmf_fweh_event_worker+0x19f/0xc60
[ 46.624603][ T7] ? mark_held_locks+0x9f/0xe0
[ 46.625145][ T7] ? lockdep_hardirqs_on_prepare+0x3e0/0x3e0
[ 46.625871][ T7] ? brcmf_cfg80211_join_ibss+0x7b0/0x7b0
[ 46.626545][ T7] brcmf_fweh_call_event_handler.isra.0+0x90/0x100
[ 46.627338][ T7] brcmf_fweh_event_worker+0x557/0xc60
[ 46.627962][ T7] ? brcmf_fweh_call_event_handler.isra.0+0x100/0x100
[ 46.628736][ T7] ? rcu_read_lock_sched_held+0xa1/0xd0
[ 46.629396][ T7] ? rcu_read_lock_bh_held+0xb0/0xb0
[ 46.629970][ T7] ? lockdep_hardirqs_on_prepare+0x273/0x3e0
[ 46.630649][ T7] process_one_work+0x92b/0x1460
[ 46.631205][ T7] ? pwq_dec_nr_in_flight+0x330/0x330
[ 46.631821][ T7] ? rwlock_bug.part.0+0x90/0x90
[ 46.632347][ T7] worker_thread+0x95/0xe00
[ 46.632832][ T7] ? __kthread_parkme+0x115/0x1e0
[ 46.633393][ T7] ? process_one_work+0x1460/0x1460
[ 46.633957][ T7] kthread+0x3a1/0x480
[ 46.634369][ T7] ? set_kthread_struct+0x120/0x120
[ 46.634933][ T7] ret_from_fork+0x1f/0x30
[ 46.635431][ T7]
[ 46.635687][ T7] Allocated by task 7:
[ 46.636151][ T7] kasan_save_stack+0x1b/0x40
[ 46.636628][ T7] __kasan_kmalloc+0x7c/0x90
[ 46.637108][ T7] kmem_cache_alloc_trace+0x19e/0x330
[ 46.637696][ T7] brcmf_cfg80211_attach+0x4a0/0x4040
[ 46.638275][ T7] brcmf_attach+0x389/0xd40
[ 46.638739][ T7] brcmf_usb_probe+0x12de/0x1690
[ 46.639279][ T7] usb_probe_interface+0x2aa/0x760
[ 46.639820][ T7] really_probe+0x205/0xb70
[ 46.640342][ T7] __driver_probe_device+0
---truncated---
CVSS Score
7.1
EPSS Score
0.0
Published
2025-09-15
In the Linux kernel, the following vulnerability has been resolved:
netfilter: x_tables: fix percpu counter block leak on error path when creating new netns
Here is the stack where we allocate percpu counter block:
+-< __alloc_percpu
+-< xt_percpu_counter_alloc
+-< find_check_entry # {arp,ip,ip6}_tables.c
+-< translate_table
And it can be leaked on this code path:
+-> ip6t_register_table
+-> translate_table # allocates percpu counter block
+-> xt_register_table # fails
there is no freeing of the counter block on xt_register_table fail.
Note: xt_percpu_counter_free should be called to free it like we do in
do_replace through cleanup_entry helper (or in __ip6t_unregister_table).
Probability of hitting this error path is low AFAICS (xt_register_table
can only return ENOMEM here, as it is not replacing anything, as we are
creating new netns, and it is hard to imagine that all previous
allocations succeeded and after that one in xt_register_table failed).
But it's worth fixing even the rare leak.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-15
In the Linux kernel, the following vulnerability has been resolved:
RDMA/bnxt_re: wraparound mbox producer index
Driver is not handling the wraparound of the mbox producer index correctly.
Currently the wraparound happens once u32 max is reached.
Bit 31 of the producer index register is special and should be set
only once for the first command. Because the producer index overflow
setting bit31 after a long time, FW goes to initialization sequence
and this causes FW hang.
Fix is to wraparound the mbox producer index once it reaches u16 max.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-15
In the Linux kernel, the following vulnerability has been resolved:
af_unix: Fix data-races around user->unix_inflight.
user->unix_inflight is changed under spin_lock(unix_gc_lock),
but too_many_unix_fds() reads it locklessly.
Let's annotate the write/read accesses to user->unix_inflight.
BUG: KCSAN: data-race in unix_attach_fds / unix_inflight
write to 0xffffffff8546f2d0 of 8 bytes by task 44798 on cpu 1:
unix_inflight+0x157/0x180 net/unix/scm.c:66
unix_attach_fds+0x147/0x1e0 net/unix/scm.c:123
unix_scm_to_skb net/unix/af_unix.c:1827 [inline]
unix_dgram_sendmsg+0x46a/0x14f0 net/unix/af_unix.c:1950
unix_seqpacket_sendmsg net/unix/af_unix.c:2308 [inline]
unix_seqpacket_sendmsg+0xba/0x130 net/unix/af_unix.c:2292
sock_sendmsg_nosec net/socket.c:725 [inline]
sock_sendmsg+0x148/0x160 net/socket.c:748
____sys_sendmsg+0x4e4/0x610 net/socket.c:2494
___sys_sendmsg+0xc6/0x140 net/socket.c:2548
__sys_sendmsg+0x94/0x140 net/socket.c:2577
__do_sys_sendmsg net/socket.c:2586 [inline]
__se_sys_sendmsg net/socket.c:2584 [inline]
__x64_sys_sendmsg+0x45/0x50 net/socket.c:2584
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3b/0x90 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x6e/0xd8
read to 0xffffffff8546f2d0 of 8 bytes by task 44814 on cpu 0:
too_many_unix_fds net/unix/scm.c:101 [inline]
unix_attach_fds+0x54/0x1e0 net/unix/scm.c:110
unix_scm_to_skb net/unix/af_unix.c:1827 [inline]
unix_dgram_sendmsg+0x46a/0x14f0 net/unix/af_unix.c:1950
unix_seqpacket_sendmsg net/unix/af_unix.c:2308 [inline]
unix_seqpacket_sendmsg+0xba/0x130 net/unix/af_unix.c:2292
sock_sendmsg_nosec net/socket.c:725 [inline]
sock_sendmsg+0x148/0x160 net/socket.c:748
____sys_sendmsg+0x4e4/0x610 net/socket.c:2494
___sys_sendmsg+0xc6/0x140 net/socket.c:2548
__sys_sendmsg+0x94/0x140 net/socket.c:2577
__do_sys_sendmsg net/socket.c:2586 [inline]
__se_sys_sendmsg net/socket.c:2584 [inline]
__x64_sys_sendmsg+0x45/0x50 net/socket.c:2584
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3b/0x90 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x6e/0xd8
value changed: 0x000000000000000c -> 0x000000000000000d
Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 44814 Comm: systemd-coredum Not tainted 6.4.0-11989-g6843306689af #6
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014
CVSS Score
4.7
EPSS Score
0.0
Published
2025-09-15
In the Linux kernel, the following vulnerability has been resolved:
KVM: s390/diag: fix racy access of physical cpu number in diag 9c handler
We do check for target CPU == -1, but this might change at the time we
are going to use it. Hold the physical target CPU in a local variable to
avoid out-of-bound accesses to the cpu arrays.
CVSS Score
7.8
EPSS Score
0.0
Published
2025-09-15
In the Linux kernel, the following vulnerability has been resolved:
USB: uhci: fix memory leak with using debugfs_lookup()
When calling debugfs_lookup() the result must have dput() called on it,
otherwise the memory will leak over time. To make things simpler, just
call debugfs_lookup_and_remove() instead which handles all of the logic
at once.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-15