Linux: >> Linux Kernel >> 5.12.12 Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
ipv6/addrconf: fix a potential refcount underflow for idev
Now in addrconf_mod_rs_timer(), reference idev depends on whether
rs_timer is not pending. Then modify rs_timer timeout.
There is a time gap in [1], during which if the pending rs_timer
becomes not pending. It will miss to hold idev, but the rs_timer
is activated. Thus rs_timer callback function addrconf_rs_timer()
will be executed and put idev later without holding idev. A refcount
underflow issue for idev can be caused by this.
if (!timer_pending(&idev->rs_timer))
in6_dev_hold(idev);
<--------------[1]
mod_timer(&idev->rs_timer, jiffies + when);
To fix the issue, hold idev if mod_timer() return 0.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-15
In the Linux kernel, the following vulnerability has been resolved:
irqchip/alpine-msi: Fix refcount leak in alpine_msix_init_domains
of_irq_find_parent() returns a node pointer with refcount incremented,
We should use of_node_put() on it when not needed anymore.
Add missing of_node_put() to avoid refcount leak.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-15
In the Linux kernel, the following vulnerability has been resolved:
vxlan: Fix nexthop hash size
The nexthop code expects a 31 bit hash, such as what is returned by
fib_multipath_hash() and rt6_multipath_hash(). Passing the 32 bit hash
returned by skb_get_hash() can lead to problems related to the fact that
'int hash' is a negative number when the MSB is set.
In the case of hash threshold nexthop groups, nexthop_select_path_hthr()
will disproportionately select the first nexthop group entry. In the case
of resilient nexthop groups, nexthop_select_path_res() may do an out of
bounds access in nh_buckets[], for example:
hash = -912054133
num_nh_buckets = 2
bucket_index = 65535
which leads to the following panic:
BUG: unable to handle page fault for address: ffffc900025910c8
PGD 100000067 P4D 100000067 PUD 10026b067 PMD 0
Oops: 0002 [#1] PREEMPT SMP KASAN NOPTI
CPU: 4 PID: 856 Comm: kworker/4:3 Not tainted 6.5.0-rc2+ #34
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Workqueue: ipv6_addrconf addrconf_dad_work
RIP: 0010:nexthop_select_path+0x197/0xbf0
Code: c1 e4 05 be 08 00 00 00 4c 8b 35 a4 14 7e 01 4e 8d 6c 25 00 4a 8d 7c 25 08 48 01 dd e8 c2 25 15 ff 49 8d 7d 08 e8 39 13 15 ff <4d> 89 75 08 48 89 ef e8 7d 12 15 ff 48 8b 5d 00 e8 14 55 2f 00 85
RSP: 0018:ffff88810c36f260 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 00000000002000c0 RCX: ffffffffaf02dd77
RDX: dffffc0000000000 RSI: 0000000000000008 RDI: ffffc900025910c8
RBP: ffffc900025910c0 R08: 0000000000000001 R09: fffff520004b2219
R10: ffffc900025910cf R11: 31392d2068736168 R12: 00000000002000c0
R13: ffffc900025910c0 R14: 00000000fffef608 R15: ffff88811840e900
FS: 0000000000000000(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffc900025910c8 CR3: 0000000129d00000 CR4: 0000000000750ee0
PKRU: 55555554
Call Trace:
<TASK>
? __die+0x23/0x70
? page_fault_oops+0x1ee/0x5c0
? __pfx_is_prefetch.constprop.0+0x10/0x10
? __pfx_page_fault_oops+0x10/0x10
? search_bpf_extables+0xfe/0x1c0
? fixup_exception+0x3b/0x470
? exc_page_fault+0xf6/0x110
? asm_exc_page_fault+0x26/0x30
? nexthop_select_path+0x197/0xbf0
? nexthop_select_path+0x197/0xbf0
? lock_is_held_type+0xe7/0x140
vxlan_xmit+0x5b2/0x2340
? __lock_acquire+0x92b/0x3370
? __pfx_vxlan_xmit+0x10/0x10
? __pfx___lock_acquire+0x10/0x10
? __pfx_register_lock_class+0x10/0x10
? skb_network_protocol+0xce/0x2d0
? dev_hard_start_xmit+0xca/0x350
? __pfx_vxlan_xmit+0x10/0x10
dev_hard_start_xmit+0xca/0x350
__dev_queue_xmit+0x513/0x1e20
? __pfx___dev_queue_xmit+0x10/0x10
? __pfx_lock_release+0x10/0x10
? mark_held_locks+0x44/0x90
? skb_push+0x4c/0x80
? eth_header+0x81/0xe0
? __pfx_eth_header+0x10/0x10
? neigh_resolve_output+0x215/0x310
? ip6_finish_output2+0x2ba/0xc90
ip6_finish_output2+0x2ba/0xc90
? lock_release+0x236/0x3e0
? ip6_mtu+0xbb/0x240
? __pfx_ip6_finish_output2+0x10/0x10
? find_held_lock+0x83/0xa0
? lock_is_held_type+0xe7/0x140
ip6_finish_output+0x1ee/0x780
ip6_output+0x138/0x460
? __pfx_ip6_output+0x10/0x10
? __pfx___lock_acquire+0x10/0x10
? __pfx_ip6_finish_output+0x10/0x10
NF_HOOK.constprop.0+0xc0/0x420
? __pfx_NF_HOOK.constprop.0+0x10/0x10
? ndisc_send_skb+0x2c0/0x960
? __pfx_lock_release+0x10/0x10
? __local_bh_enable_ip+0x93/0x110
? lock_is_held_type+0xe7/0x140
ndisc_send_skb+0x4be/0x960
? __pfx_ndisc_send_skb+0x10/0x10
? mark_held_locks+0x65/0x90
? find_held_lock+0x83/0xa0
ndisc_send_ns+0xb0/0x110
? __pfx_ndisc_send_ns+0x10/0x10
addrconf_dad_work+0x631/0x8e0
? lock_acquire+0x180/0x3f0
? __pfx_addrconf_dad_work+0x10/0x10
? mark_held_locks+0x24/0x90
process_one_work+0x582/0x9c0
? __pfx_process_one_work+0x10/0x10
? __pfx_do_raw_spin_lock+0x10/0x10
? mark_held_locks+0x24/0x90
worker_thread+0x93/0x630
? __kthread_parkme+0xdc/0x100
? __pfx_worker_thread+0x10/0x10
kthread+0x1a5/0x1e0
? __pfx_kthread+0x10/0x10
ret_from_fork+0x34/0x60
---truncated---
CVSS Score
7.8
EPSS Score
0.0
Published
2025-09-15
In the Linux kernel, the following vulnerability has been resolved:
usb: dwc3: qcom: Fix potential memory leak
Function dwc3_qcom_probe() allocates memory for resource structure
which is pointed by parent_res pointer. This memory is not
freed. This leads to memory leak. Use stack memory to prevent
memory leak.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-15
In the Linux kernel, the following vulnerability has been resolved:
ACPICA: Avoid undefined behavior: applying zero offset to null pointer
ACPICA commit 770653e3ba67c30a629ca7d12e352d83c2541b1e
Before this change we see the following UBSAN stack trace in Fuchsia:
#0 0x000021e4213b3302 in acpi_ds_init_aml_walk(struct acpi_walk_state*, union acpi_parse_object*, struct acpi_namespace_node*, u8*, u32, struct acpi_evaluate_info*, u8) ../../third_party/acpica/source/components/dispatcher/dswstate.c:682 <platform-bus-x86.so>+0x233302
#1.2 0x000020d0f660777f in ubsan_get_stack_trace() compiler-rt/lib/ubsan/ubsan_diag.cpp:41 <libclang_rt.asan.so>+0x3d77f
#1.1 0x000020d0f660777f in maybe_print_stack_trace() compiler-rt/lib/ubsan/ubsan_diag.cpp:51 <libclang_rt.asan.so>+0x3d77f
#1 0x000020d0f660777f in ~scoped_report() compiler-rt/lib/ubsan/ubsan_diag.cpp:387 <libclang_rt.asan.so>+0x3d77f
#2 0x000020d0f660b96d in handlepointer_overflow_impl() compiler-rt/lib/ubsan/ubsan_handlers.cpp:809 <libclang_rt.asan.so>+0x4196d
#3 0x000020d0f660b50d in compiler-rt/lib/ubsan/ubsan_handlers.cpp:815 <libclang_rt.asan.so>+0x4150d
#4 0x000021e4213b3302 in acpi_ds_init_aml_walk(struct acpi_walk_state*, union acpi_parse_object*, struct acpi_namespace_node*, u8*, u32, struct acpi_evaluate_info*, u8) ../../third_party/acpica/source/components/dispatcher/dswstate.c:682 <platform-bus-x86.so>+0x233302
#5 0x000021e4213e2369 in acpi_ds_call_control_method(struct acpi_thread_state*, struct acpi_walk_state*, union acpi_parse_object*) ../../third_party/acpica/source/components/dispatcher/dsmethod.c:605 <platform-bus-x86.so>+0x262369
#6 0x000021e421437fac in acpi_ps_parse_aml(struct acpi_walk_state*) ../../third_party/acpica/source/components/parser/psparse.c:550 <platform-bus-x86.so>+0x2b7fac
#7 0x000021e4214464d2 in acpi_ps_execute_method(struct acpi_evaluate_info*) ../../third_party/acpica/source/components/parser/psxface.c:244 <platform-bus-x86.so>+0x2c64d2
#8 0x000021e4213aa052 in acpi_ns_evaluate(struct acpi_evaluate_info*) ../../third_party/acpica/source/components/namespace/nseval.c:250 <platform-bus-x86.so>+0x22a052
#9 0x000021e421413dd8 in acpi_ns_init_one_device(acpi_handle, u32, void*, void**) ../../third_party/acpica/source/components/namespace/nsinit.c:735 <platform-bus-x86.so>+0x293dd8
#10 0x000021e421429e98 in acpi_ns_walk_namespace(acpi_object_type, acpi_handle, u32, u32, acpi_walk_callback, acpi_walk_callback, void*, void**) ../../third_party/acpica/source/components/namespace/nswalk.c:298 <platform-bus-x86.so>+0x2a9e98
#11 0x000021e4214131ac in acpi_ns_initialize_devices(u32) ../../third_party/acpica/source/components/namespace/nsinit.c:268 <platform-bus-x86.so>+0x2931ac
#12 0x000021e42147c40d in acpi_initialize_objects(u32) ../../third_party/acpica/source/components/utilities/utxfinit.c:304 <platform-bus-x86.so>+0x2fc40d
#13 0x000021e42126d603 in acpi::acpi_impl::initialize_acpi(acpi::acpi_impl*) ../../src/devices/board/lib/acpi/acpi-impl.cc:224 <platform-bus-x86.so>+0xed603
Add a simple check that avoids incrementing a pointer by zero, but
otherwise behaves as before. Note that our findings are against ACPICA
20221020, but the same code exists on master.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-15
In the Linux kernel, the following vulnerability has been resolved:
wifi: ath9k: don't allow to overwrite ENDPOINT0 attributes
A bad USB device is able to construct a service connection response
message with target endpoint being ENDPOINT0 which is reserved for
HTC_CTRL_RSVD_SVC and should not be modified to be used for any other
services.
Reject such service connection responses.
Found by Linux Verification Center (linuxtesting.org) with Syzkaller.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-15
In the Linux kernel, the following vulnerability has been resolved:
tty: pcn_uart: 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
In the Linux kernel, the following vulnerability has been resolved:
scsi: core: Fix possible memory leak if device_add() fails
If device_add() returns error, the name allocated by dev_set_name() needs
be freed. As the comment of device_add() says, put_device() should be used
to decrease the reference count in the error path. So fix this by calling
put_device(), then the name can be freed in kobject_cleanp().
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-15
In the Linux kernel, the following vulnerability has been resolved:
serial: 8250: Reinit port->pm on port specific driver unbind
When we unbind a serial port hardware specific 8250 driver, the generic
serial8250 driver takes over the port. After that we see an oops about 10
seconds later. This can produce the following at least on some TI SoCs:
Unhandled fault: imprecise external abort (0x1406)
Internal error: : 1406 [#1] SMP ARM
Turns out that we may still have the serial port hardware specific driver
port->pm in use, and serial8250_pm() tries to call it after the port
specific driver is gone:
serial8250_pm [8250_base] from uart_change_pm+0x54/0x8c [serial_base]
uart_change_pm [serial_base] from uart_hangup+0x154/0x198 [serial_base]
uart_hangup [serial_base] from __tty_hangup.part.0+0x328/0x37c
__tty_hangup.part.0 from disassociate_ctty+0x154/0x20c
disassociate_ctty from do_exit+0x744/0xaac
do_exit from do_group_exit+0x40/0x8c
do_group_exit from __wake_up_parent+0x0/0x1c
Let's fix the issue by calling serial8250_set_defaults() in
serial8250_unregister_port(). This will set the port back to using
the serial8250 default functions, and sets the port->pm to point to
serial8250_pm.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-15
In the Linux kernel, the following vulnerability has been resolved:
mm: fix zswap writeback race condition
The zswap writeback mechanism can cause a race condition resulting in
memory corruption, where a swapped out page gets swapped in with data that
was written to a different page.
The race unfolds like this:
1. a page with data A and swap offset X is stored in zswap
2. page A is removed off the LRU by zpool driver for writeback in
zswap-shrink work, data for A is mapped by zpool driver
3. user space program faults and invalidates page entry A, offset X is
considered free
4. kswapd stores page B at offset X in zswap (zswap could also be
full, if so, page B would then be IOed to X, then skip step 5.)
5. entry A is replaced by B in tree->rbroot, this doesn't affect the
local reference held by zswap-shrink work
6. zswap-shrink work writes back A at X, and frees zswap entry A
7. swapin of slot X brings A in memory instead of B
The fix:
Once the swap page cache has been allocated (case ZSWAP_SWAPCACHE_NEW),
zswap-shrink work just checks that the local zswap_entry reference is
still the same as the one in the tree. If it's not the same it means that
it's either been invalidated or replaced, in both cases the writeback is
aborted because the local entry contains stale data.
Reproducer:
I originally found this by running `stress` overnight to validate my work
on the zswap writeback mechanism, it manifested after hours on my test
machine. The key to make it happen is having zswap writebacks, so
whatever setup pumps /sys/kernel/debug/zswap/written_back_pages should do
the trick.
In order to reproduce this faster on a vm, I setup a system with ~100M of
available memory and a 500M swap file, then running `stress --vm 1
--vm-bytes 300000000 --vm-stride 4000` makes it happen in matter of tens
of minutes. One can speed things up even more by swinging
/sys/module/zswap/parameters/max_pool_percent up and down between, say, 20
and 1; this makes it reproduce in tens of seconds. It's crucial to set
`--vm-stride` to something other than 4096 otherwise `stress` won't
realize that memory has been corrupted because all pages would have the
same data.
CVSS Score
4.7
EPSS Score
0.0
Published
2025-09-15