Linux: >> Linux Kernel >> 4.12.2 Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
HID: asus: fix UAF via HID_CLAIMED_INPUT validation
After hid_hw_start() is called hidinput_connect() will eventually be
called to set up the device with the input layer since the
HID_CONNECT_DEFAULT connect mask is used. During hidinput_connect()
all input and output reports are processed and corresponding hid_inputs
are allocated and configured via hidinput_configure_usages(). This
process involves slot tagging report fields and configuring usages
by setting relevant bits in the capability bitmaps. However it is possible
that the capability bitmaps are not set at all leading to the subsequent
hidinput_has_been_populated() check to fail leading to the freeing of the
hid_input and the underlying input device.
This becomes problematic because a malicious HID device like a
ASUS ROG N-Key keyboard can trigger the above scenario via a
specially crafted descriptor which then leads to a user-after-free
when the name of the freed input device is written to later on after
hid_hw_start(). Below, report 93 intentionally utilises the
HID_UP_UNDEFINED Usage Page which is skipped during usage
configuration, leading to the frees.
0x05, 0x0D, // Usage Page (Digitizer)
0x09, 0x05, // Usage (Touch Pad)
0xA1, 0x01, // Collection (Application)
0x85, 0x0D, // Report ID (13)
0x06, 0x00, 0xFF, // Usage Page (Vendor Defined 0xFF00)
0x09, 0xC5, // Usage (0xC5)
0x15, 0x00, // Logical Minimum (0)
0x26, 0xFF, 0x00, // Logical Maximum (255)
0x75, 0x08, // Report Size (8)
0x95, 0x04, // Report Count (4)
0xB1, 0x02, // Feature (Data,Var,Abs)
0x85, 0x5D, // Report ID (93)
0x06, 0x00, 0x00, // Usage Page (Undefined)
0x09, 0x01, // Usage (0x01)
0x15, 0x00, // Logical Minimum (0)
0x26, 0xFF, 0x00, // Logical Maximum (255)
0x75, 0x08, // Report Size (8)
0x95, 0x1B, // Report Count (27)
0x81, 0x02, // Input (Data,Var,Abs)
0xC0, // End Collection
Below is the KASAN splat after triggering the UAF:
[ 21.672709] ==================================================================
[ 21.673700] BUG: KASAN: slab-use-after-free in asus_probe+0xeeb/0xf80
[ 21.673700] Write of size 8 at addr ffff88810a0ac000 by task kworker/1:2/54
[ 21.673700]
[ 21.673700] CPU: 1 UID: 0 PID: 54 Comm: kworker/1:2 Not tainted 6.16.0-rc4-g9773391cf4dd-dirty #36 PREEMPT(voluntary)
[ 21.673700] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
[ 21.673700] Call Trace:
[ 21.673700] <TASK>
[ 21.673700] dump_stack_lvl+0x5f/0x80
[ 21.673700] print_report+0xd1/0x660
[ 21.673700] kasan_report+0xe5/0x120
[ 21.673700] __asan_report_store8_noabort+0x1b/0x30
[ 21.673700] asus_probe+0xeeb/0xf80
[ 21.673700] hid_device_probe+0x2ee/0x700
[ 21.673700] really_probe+0x1c6/0x6b0
[ 21.673700] __driver_probe_device+0x24f/0x310
[ 21.673700] driver_probe_device+0x4e/0x220
[...]
[ 21.673700]
[ 21.673700] Allocated by task 54:
[ 21.673700] kasan_save_stack+0x3d/0x60
[ 21.673700] kasan_save_track+0x18/0x40
[ 21.673700] kasan_save_alloc_info+0x3b/0x50
[ 21.673700] __kasan_kmalloc+0x9c/0xa0
[ 21.673700] __kmalloc_cache_noprof+0x139/0x340
[ 21.673700] input_allocate_device+0x44/0x370
[ 21.673700] hidinput_connect+0xcb6/0x2630
[ 21.673700] hid_connect+0xf74/0x1d60
[ 21.673700] hid_hw_start+0x8c/0x110
[ 21.673700] asus_probe+0x5a3/0xf80
[ 21.673700] hid_device_probe+0x2ee/0x700
[ 21.673700] really_probe+0x1c6/0x6b0
[ 21.673700] __driver_probe_device+0x24f/0x310
[ 21.673700] driver_probe_device+0x4e/0x220
[...]
[ 21.673700]
[ 21.673700] Freed by task 54:
[ 21.673700] kasan_save_stack+0x3d/0x60
[ 21.673700] kasan_save_track+0x18/0x40
[ 21.673700] kasan_save_free_info+0x3f/0x60
[ 21.673700] __kasan_slab_free+0x3c/0x50
[ 21.673700] kfre
---truncated---
CVSS Score
7.8
EPSS Score
0.0
Published
2025-09-16
In the Linux kernel, the following vulnerability has been resolved:
efivarfs: Fix slab-out-of-bounds in efivarfs_d_compare
Observed on kernel 6.6 (present on master as well):
BUG: KASAN: slab-out-of-bounds in memcmp+0x98/0xd0
Call trace:
kasan_check_range+0xe8/0x190
__asan_loadN+0x1c/0x28
memcmp+0x98/0xd0
efivarfs_d_compare+0x68/0xd8
__d_lookup_rcu_op_compare+0x178/0x218
__d_lookup_rcu+0x1f8/0x228
d_alloc_parallel+0x150/0x648
lookup_open.isra.0+0x5f0/0x8d0
open_last_lookups+0x264/0x828
path_openat+0x130/0x3f8
do_filp_open+0x114/0x248
do_sys_openat2+0x340/0x3c0
__arm64_sys_openat+0x120/0x1a0
If dentry->d_name.len < EFI_VARIABLE_GUID_LEN , 'guid' can become
negative, leadings to oob. The issue can be triggered by parallel
lookups using invalid filename:
T1 T2
lookup_open
->lookup
simple_lookup
d_add
// invalid dentry is added to hash list
lookup_open
d_alloc_parallel
__d_lookup_rcu
__d_lookup_rcu_op_compare
hlist_bl_for_each_entry_rcu
// invalid dentry can be retrieved
->d_compare
efivarfs_d_compare
// oob
Fix it by checking 'guid' before cmp.
CVSS Score
7.1
EPSS Score
0.0
Published
2025-09-16
In the Linux kernel, the following vulnerability has been resolved:
ftrace: Fix potential warning in trace_printk_seq during ftrace_dump
When calling ftrace_dump_one() concurrently with reading trace_pipe,
a WARN_ON_ONCE() in trace_printk_seq() can be triggered due to a race
condition.
The issue occurs because:
CPU0 (ftrace_dump) CPU1 (reader)
echo z > /proc/sysrq-trigger
!trace_empty(&iter)
trace_iterator_reset(&iter) <- len = size = 0
cat /sys/kernel/tracing/trace_pipe
trace_find_next_entry_inc(&iter)
__find_next_entry
ring_buffer_empty_cpu <- all empty
return NULL
trace_printk_seq(&iter.seq)
WARN_ON_ONCE(s->seq.len >= s->seq.size)
In the context between trace_empty() and trace_find_next_entry_inc()
during ftrace_dump, the ring buffer data was consumed by other readers.
This caused trace_find_next_entry_inc to return NULL, failing to populate
`iter.seq`. At this point, due to the prior trace_iterator_reset, both
`iter.seq.len` and `iter.seq.size` were set to 0. Since they are equal,
the WARN_ON_ONCE condition is triggered.
Move the trace_printk_seq() into the if block that checks to make sure the
return value of trace_find_next_entry_inc() is non-NULL in
ftrace_dump_one(), ensuring the 'iter.seq' is properly populated before
subsequent operations.
CVSS Score
4.7
EPSS Score
0.0
Published
2025-09-16
In the Linux kernel, the following vulnerability has been resolved:
sctp: initialize more fields in sctp_v6_from_sk()
syzbot found that sin6_scope_id was not properly initialized,
leading to undefined behavior.
Clear sin6_scope_id and sin6_flowinfo.
BUG: KMSAN: uninit-value in __sctp_v6_cmp_addr+0x887/0x8c0 net/sctp/ipv6.c:649
__sctp_v6_cmp_addr+0x887/0x8c0 net/sctp/ipv6.c:649
sctp_inet6_cmp_addr+0x4f2/0x510 net/sctp/ipv6.c:983
sctp_bind_addr_conflict+0x22a/0x3b0 net/sctp/bind_addr.c:390
sctp_get_port_local+0x21eb/0x2440 net/sctp/socket.c:8452
sctp_get_port net/sctp/socket.c:8523 [inline]
sctp_listen_start net/sctp/socket.c:8567 [inline]
sctp_inet_listen+0x710/0xfd0 net/sctp/socket.c:8636
__sys_listen_socket net/socket.c:1912 [inline]
__sys_listen net/socket.c:1927 [inline]
__do_sys_listen net/socket.c:1932 [inline]
__se_sys_listen net/socket.c:1930 [inline]
__x64_sys_listen+0x343/0x4c0 net/socket.c:1930
x64_sys_call+0x271d/0x3e20 arch/x86/include/generated/asm/syscalls_64.h:51
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xd9/0x210 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Local variable addr.i.i created at:
sctp_get_port net/sctp/socket.c:8515 [inline]
sctp_listen_start net/sctp/socket.c:8567 [inline]
sctp_inet_listen+0x650/0xfd0 net/sctp/socket.c:8636
__sys_listen_socket net/socket.c:1912 [inline]
__sys_listen net/socket.c:1927 [inline]
__do_sys_listen net/socket.c:1932 [inline]
__se_sys_listen net/socket.c:1930 [inline]
__x64_sys_listen+0x343/0x4c0 net/socket.c:1930
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-16
In the Linux kernel, the following vulnerability has been resolved:
HID: hid-ntrig: fix unable to handle page fault in ntrig_report_version()
in ntrig_report_version(), hdev parameter passed from hid_probe().
sending descriptor to /dev/uhid can make hdev->dev.parent->parent to null
if hdev->dev.parent->parent is null, usb_dev has
invalid address(0xffffffffffffff58) that hid_to_usb_dev(hdev) returned
when usb_rcvctrlpipe() use usb_dev,it trigger
page fault error for address(0xffffffffffffff58)
add null check logic to ntrig_report_version()
before calling hid_to_usb_dev()
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-16
In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: L2CAP: fix "bad unlock balance" in l2cap_disconnect_rsp
conn->chan_lock isn't acquired before l2cap_get_chan_by_scid,
if l2cap_get_chan_by_scid returns NULL, then 'bad unlock balance'
is triggered.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-16
In the Linux kernel, the following vulnerability has been resolved:
nfc: fix memory leak of se_io context in nfc_genl_se_io
The callback context for sending/receiving APDUs to/from the selected
secure element is allocated inside nfc_genl_se_io and supposed to be
eventually freed in se_io_cb callback function. However, there are several
error paths where the bwi_timer is not charged to call se_io_cb later, and
the cb_context is leaked.
The patch proposes to free the cb_context explicitly on those error paths.
At the moment we can't simply check 'dev->ops->se_io()' return value as it
may be negative in both cases: when the timer was charged and was not.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-16
In the Linux kernel, the following vulnerability has been resolved:
md/raid10: fix leak of 'r10bio->remaining' for recovery
raid10_sync_request() will add 'r10bio->remaining' for both rdev and
replacement rdev. However, if the read io fails, recovery_request_write()
returns without issuing the write io, in this case, end_sync_request()
is only called once and 'remaining' is leaked, cause an io hang.
Fix the problem by decreasing 'remaining' according to if 'bio' and
'repl_bio' is valid.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-16
In the Linux kernel, the following vulnerability has been resolved:
wifi: iwl4965: Add missing check for create_singlethread_workqueue()
Add the check for the return value of the create_singlethread_workqueue()
in order to avoid NULL pointer dereference.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-16
In the Linux kernel, the following vulnerability has been resolved:
media: bdisp: Add missing check for create_workqueue
Add the check for the return value of the create_workqueue
in order to avoid NULL pointer dereference.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-16