Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
drm: Do not allow userspace to trigger kernel warnings in drm_gem_change_handle_ioctl()
Since GEM bo handles are u32 in the uapi and the internal implementation
uses idr_alloc() which uses int ranges, passing a new handle larger than
INT_MAX trivially triggers a kernel warning:
idr_alloc():
...
if (WARN_ON_ONCE(start < 0))
return -EINVAL;
...
Fix it by rejecting new handles above INT_MAX and at the same time make
the end limit calculation more obvious by moving into int domain.
CVSS Score
5.5
EPSS Score
0.0
Published
2026-02-14
In the Linux kernel, the following vulnerability has been resolved:
nfc: llcp: Fix memleak in nfc_llcp_send_ui_frame().
syzbot reported various memory leaks related to NFC, struct
nfc_llcp_sock, sk_buff, nfc_dev, etc. [0]
The leading log hinted that nfc_llcp_send_ui_frame() failed
to allocate skb due to sock_error(sk) being -ENXIO.
ENXIO is set by nfc_llcp_socket_release() when struct
nfc_llcp_local is destroyed by local_cleanup().
The problem is that there is no synchronisation between
nfc_llcp_send_ui_frame() and local_cleanup(), and skb
could be put into local->tx_queue after it was purged in
local_cleanup():
CPU1 CPU2
---- ----
nfc_llcp_send_ui_frame() local_cleanup()
|- do { '
|- pdu = nfc_alloc_send_skb(..., &err)
| .
| |- nfc_llcp_socket_release(local, false, ENXIO);
| |- skb_queue_purge(&local->tx_queue); |
| ' |
|- skb_queue_tail(&local->tx_queue, pdu); |
... |
|- pdu = nfc_alloc_send_skb(..., &err) |
^._________________________________.'
local_cleanup() is called for struct nfc_llcp_local only
after nfc_llcp_remove_local() unlinks it from llcp_devices.
If we hold local->tx_queue.lock then, we can synchronise
the thread and nfc_llcp_send_ui_frame().
Let's do that and check list_empty(&local->list) before
queuing skb to local->tx_queue in nfc_llcp_send_ui_frame().
[0]:
[ 56.074943][ T6096] llcp: nfc_llcp_send_ui_frame: Could not allocate PDU (error=-6)
[ 64.318868][ T5813] kmemleak: 6 new suspected memory leaks (see /sys/kernel/debug/kmemleak)
BUG: memory leak
unreferenced object 0xffff8881272f6800 (size 1024):
comm "syz.0.17", pid 6096, jiffies 4294942766
hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
27 00 03 40 00 00 00 00 00 00 00 00 00 00 00 00 '..@............
backtrace (crc da58d84d):
kmemleak_alloc_recursive include/linux/kmemleak.h:44 [inline]
slab_post_alloc_hook mm/slub.c:4979 [inline]
slab_alloc_node mm/slub.c:5284 [inline]
__do_kmalloc_node mm/slub.c:5645 [inline]
__kmalloc_noprof+0x3e3/0x6b0 mm/slub.c:5658
kmalloc_noprof include/linux/slab.h:961 [inline]
sk_prot_alloc+0x11a/0x1b0 net/core/sock.c:2239
sk_alloc+0x36/0x360 net/core/sock.c:2295
nfc_llcp_sock_alloc+0x37/0x130 net/nfc/llcp_sock.c:979
llcp_sock_create+0x71/0xd0 net/nfc/llcp_sock.c:1044
nfc_sock_create+0xc9/0xf0 net/nfc/af_nfc.c:31
__sock_create+0x1a9/0x340 net/socket.c:1605
sock_create net/socket.c:1663 [inline]
__sys_socket_create net/socket.c:1700 [inline]
__sys_socket+0xb9/0x1a0 net/socket.c:1747
__do_sys_socket net/socket.c:1761 [inline]
__se_sys_socket net/socket.c:1759 [inline]
__x64_sys_socket+0x1b/0x30 net/socket.c:1759
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xa4/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
BUG: memory leak
unreferenced object 0xffff88810fbd9800 (size 240):
comm "syz.0.17", pid 6096, jiffies 4294942850
hex dump (first 32 bytes):
68 f0 ff 08 81 88 ff ff 68 f0 ff 08 81 88 ff ff h.......h.......
00 00 00 00 00 00 00 00 00 68 2f 27 81 88 ff ff .........h/'....
backtrace (crc 6cc652b1):
kmemleak_alloc_recursive include/linux/kmemleak.h:44 [inline]
slab_post_alloc_hook mm/slub.c:4979 [inline]
slab_alloc_node mm/slub.c:5284 [inline]
kmem_cache_alloc_node_noprof+0x36f/0x5e0 mm/slub.c:5336
__alloc_skb+0x203/0x240 net/core/skbuff.c:660
alloc_skb include/linux/skbuff.h:1383 [inline]
alloc_skb_with_frags+0x69/0x3f0 net/core/sk
---truncated---
CVSS Score
5.5
EPSS Score
0.0
Published
2026-02-14
In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: MGMT: Fix memory leak in set_ssp_complete
Fix memory leak in set_ssp_complete() where mgmt_pending_cmd structures
are not freed after being removed from the pending list.
Commit 302a1f674c00 ("Bluetooth: MGMT: Fix possible UAFs") replaced
mgmt_pending_foreach() calls with individual command handling but missed
adding mgmt_pending_free() calls in both error and success paths of
set_ssp_complete(). Other completion functions like set_le_complete()
were fixed correctly in the same commit.
This causes a memory leak of the mgmt_pending_cmd structure and its
associated parameter data for each SSP command that completes.
Add the missing mgmt_pending_free(cmd) calls in both code paths to fix
the memory leak. Also fix the same issue in set_advertising_complete().
CVSS Score
5.5
EPSS Score
0.0
Published
2026-02-14
In the Linux kernel, the following vulnerability has been resolved:
wifi: mac80211: correctly decode TTLM with default link map
TID-To-Link Mapping (TTLM) elements do not contain any link mapping
presence indicator if a default mapping is used and parsing needs to be
skipped.
Note that access points should not explicitly report an advertised TTLM
with a default mapping as that is the implied mapping if the element is
not included, this is even the case when switching back to the default
mapping. However, mac80211 would incorrectly parse the frame and would
also read one byte beyond the end of the element.
CVSS Score
5.5
EPSS Score
0.0
Published
2026-02-14
In the Linux kernel, the following vulnerability has been resolved:
firewire: core: fix race condition against transaction list
The list of transaction is enumerated without acquiring card lock when
processing AR response event. This causes a race condition bug when
processing AT request completion event concurrently.
This commit fixes the bug by put timer start for split transaction
expiration into the scope of lock. The value of jiffies in card structure
is referred before acquiring the lock.
CVSS Score
4.7
EPSS Score
0.0
Published
2026-02-14
In the Linux kernel, the following vulnerability has been resolved:
net: fix segmentation of forwarding fraglist GRO
This patch enhances GSO segment handling by properly checking
the SKB_GSO_DODGY flag for frag_list GSO packets, addressing
low throughput issues observed when a station accesses IPv4
servers via hotspots with an IPv6-only upstream interface.
Specifically, it fixes a bug in GSO segmentation when forwarding
GRO packets containing a frag_list. The function skb_segment_list
cannot correctly process GRO skbs that have been converted by XLAT,
since XLAT only translates the header of the head skb. Consequently,
skbs in the frag_list may remain untranslated, resulting in protocol
inconsistencies and reduced throughput.
To address this, the patch explicitly sets the SKB_GSO_DODGY flag
for GSO packets in XLAT's IPv4/IPv6 protocol translation helpers
(bpf_skb_proto_4_to_6 and bpf_skb_proto_6_to_4). This marks GSO
packets as potentially modified after protocol translation. As a
result, GSO segmentation will avoid using skb_segment_list and
instead falls back to skb_segment for packets with the SKB_GSO_DODGY
flag. This ensures that only safe and fully translated frag_list
packets are processed by skb_segment_list, resolving protocol
inconsistencies and improving throughput when forwarding GRO packets
converted by XLAT.
CVSS Score
5.5
EPSS Score
0.0
Published
2026-02-14
In the Linux kernel, the following vulnerability has been resolved:
can: gs_usb: gs_usb_receive_bulk_callback(): fix error message
Sinc commit 79a6d1bfe114 ("can: gs_usb: gs_usb_receive_bulk_callback():
unanchor URL on usb_submit_urb() error") a failing resubmit URB will print
an info message.
In the case of a short read where netdev has not yet been assigned,
initialize as NULL to avoid dereferencing an undefined value. Also report
the error value of the failed resubmit.
CVSS Score
5.5
EPSS Score
0.0
Published
2026-02-14
In the Linux kernel, the following vulnerability has been resolved:
efivarfs: fix error propagation in efivar_entry_get()
efivar_entry_get() always returns success even if the underlying
__efivar_entry_get() fails, masking errors.
This may result in uninitialized heap memory being copied to userspace
in the efivarfs_file_read() path.
Fix it by returning the error from __efivar_entry_get().
CVSS Score
7.8
EPSS Score
0.0
Published
2026-02-14
In the Linux kernel, the following vulnerability has been resolved:
btrfs: do not strictly require dirty metadata threshold for metadata writepages
[BUG]
There is an internal report that over 1000 processes are
waiting at the io_schedule_timeout() of balance_dirty_pages(), causing
a system hang and trigger a kernel coredump.
The kernel is v6.4 kernel based, but the root problem still applies to
any upstream kernel before v6.18.
[CAUSE]
From Jan Kara for his wisdom on the dirty page balance behavior first.
This cgroup dirty limit was what was actually playing the role here
because the cgroup had only a small amount of memory and so the dirty
limit for it was something like 16MB.
Dirty throttling is responsible for enforcing that nobody can dirty
(significantly) more dirty memory than there's dirty limit. Thus when
a task is dirtying pages it periodically enters into balance_dirty_pages()
and we let it sleep there to slow down the dirtying.
When the system is over dirty limit already (either globally or within
a cgroup of the running task), we will not let the task exit from
balance_dirty_pages() until the number of dirty pages drops below the
limit.
So in this particular case, as I already mentioned, there was a cgroup
with relatively small amount of memory and as a result with dirty limit
set at 16MB. A task from that cgroup has dirtied about 28MB worth of
pages in btrfs btree inode and these were practically the only dirty
pages in that cgroup.
So that means the only way to reduce the dirty pages of that cgroup is
to writeback the dirty pages of btrfs btree inode, and only after that
those processes can exit balance_dirty_pages().
Now back to the btrfs part, btree_writepages() is responsible for
writing back dirty btree inode pages.
The problem here is, there is a btrfs internal threshold that if the
btree inode's dirty bytes are below the 32M threshold, it will not
do any writeback.
This behavior is to batch as much metadata as possible so we won't write
back those tree blocks and then later re-COW them again for another
modification.
This internal 32MiB is higher than the existing dirty page size (28MiB),
meaning no writeback will happen, causing a deadlock between btrfs and
cgroup:
- Btrfs doesn't want to write back btree inode until more dirty pages
- Cgroup/MM doesn't want more dirty pages for btrfs btree inode
Thus any process touching that btree inode is put into sleep until
the number of dirty pages is reduced.
Thanks Jan Kara a lot for the analysis of the root cause.
[ENHANCEMENT]
Since kernel commit b55102826d7d ("btrfs: set AS_KERNEL_FILE on the
btree_inode"), btrfs btree inode pages will only be charged to the root
cgroup which should have a much larger limit than btrfs' 32MiB
threshold.
So it should not affect newer kernels.
But for all current LTS kernels, they are all affected by this problem,
and backporting the whole AS_KERNEL_FILE may not be a good idea.
Even for newer kernels I still think it's a good idea to get
rid of the internal threshold at btree_writepages(), since for most cases
cgroup/MM has a better view of full system memory usage than btrfs' fixed
threshold.
For internal callers using btrfs_btree_balance_dirty() since that
function is already doing internal threshold check, we don't need to
bother them.
But for external callers of btree_writepages(), just respect their
requests and write back whatever they want, ignoring the internal
btrfs threshold to avoid such deadlock on btree inode dirty page
balancing.
CVSS Score
5.5
EPSS Score
0.0
Published
2026-02-14
In the Linux kernel, the following vulnerability has been resolved:
gpio: virtuser: fix UAF in configfs release path
The gpio-virtuser configfs release path uses guard(mutex) to protect
the device structure. However, the device is freed before the guard
cleanup runs, causing mutex_unlock() to operate on freed memory.
Specifically, gpio_virtuser_device_config_group_release() destroys
the mutex and frees the device while still inside the guard(mutex)
scope. When the function returns, the guard cleanup invokes
mutex_unlock(&dev->lock), resulting in a slab use-after-free.
Limit the mutex lifetime by using a scoped_guard() only around the
activation check, so that the lock is released before mutex_destroy()
and kfree() are called.
CVSS Score
7.8
EPSS Score
0.0
Published
2026-02-14