Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
net: stmmac: fix integer underflow in chain mode
The jumbo_frm() chain-mode implementation unconditionally computes
len = nopaged_len - bmax;
where nopaged_len = skb_headlen(skb) (linear bytes only) and bmax is
BUF_SIZE_8KiB or BUF_SIZE_2KiB. However, the caller stmmac_xmit()
decides to invoke jumbo_frm() based on skb->len (total length including
page fragments):
is_jumbo = stmmac_is_jumbo_frm(priv, skb->len, enh_desc);
When a packet has a small linear portion (nopaged_len <= bmax) but a
large total length due to page fragments (skb->len > bmax), the
subtraction wraps as an unsigned integer, producing a huge len value
(~0xFFFFxxxx). This causes the while (len != 0) loop to execute
hundreds of thousands of iterations, passing skb->data + bmax * i
pointers far beyond the skb buffer to dma_map_single(). On IOMMU-less
SoCs (the typical deployment for stmmac), this maps arbitrary kernel
memory to the DMA engine, constituting a kernel memory disclosure and
potential memory corruption from hardware.
Fix this by introducing a buf_len local variable clamped to
min(nopaged_len, bmax). Computing len = nopaged_len - buf_len is then
always safe: it is zero when the linear portion fits within a single
descriptor, causing the while (len != 0) loop to be skipped naturally,
and the fragment loop in stmmac_xmit() handles page fragments afterward.
CVSS Score
9.8
EPSS Score
0.001
Published
2026-04-24
In the Linux kernel, the following vulnerability has been resolved:
mmc: vub300: fix use-after-free on disconnect
The vub300 driver maintains an explicit reference count for the
controller and its driver data and the last reference can in theory be
dropped after the driver has been unbound.
This specifically means that the controller allocation must not be
device managed as that can lead to use-after-free.
Note that the lifetime is currently also incorrectly tied the parent USB
device rather than interface, which can lead to memory leaks if the
driver is unbound without its device being physically disconnected (e.g.
on probe deferral).
Fix both issues by reverting to non-managed allocation of the controller.
CVSS Score
7.8
EPSS Score
0.0
Published
2026-04-24
In the Linux kernel, the following vulnerability has been resolved:
mmc: vub300: fix NULL-deref on disconnect
Make sure to deregister the controller before dropping the reference to
the driver data on disconnect to avoid NULL-pointer dereferences or
use-after-free.
CVSS Score
5.5
EPSS Score
0.0
Published
2026-04-24
In the Linux kernel, the following vulnerability has been resolved:
mm/damon/stat: deallocate damon_call() failure leaking damon_ctx
damon_stat_start() always allocates the module's damon_ctx object
(damon_stat_context). Meanwhile, if damon_call() in the function fails,
the damon_ctx object is not deallocated. Hence, if the damon_call() is
failed, and the user writes Y to “enabled” again, the previously
allocated damon_ctx object is leaked.
This cannot simply be fixed by deallocating the damon_ctx object when
damon_call() fails. That's because damon_call() failure doesn't guarantee
the kdamond main function, which accesses the damon_ctx object, is
completely finished. In other words, if damon_stat_start() deallocates
the damon_ctx object after damon_call() failure, the not-yet-terminated
kdamond could access the freed memory (use-after-free).
Fix the leak while avoiding the use-after-free by keeping returning
damon_stat_start() without deallocating the damon_ctx object after
damon_call() failure, but deallocating it when the function is invoked
again and the kdamond is completely terminated. If the kdamond is not yet
terminated, simply return -EAGAIN, as the kdamond will soon be terminated.
The issue was discovered [1] by sashiko.
CVSS Score
7.8
EPSS Score
0.0
Published
2026-04-24
In the Linux kernel, the following vulnerability has been resolved:
mm/damon/sysfs: dealloc repeat_call_control if damon_call() fails
damon_call() for repeat_call_control of DAMON_SYSFS could fail if somehow
the kdamond is stopped before the damon_call(). It could happen, for
example, when te damon context was made for monitroing of a virtual
address processes, and the process is terminated immediately, before the
damon_call() invocation. In the case, the dyanmically allocated
repeat_call_control is not deallocated and leaked.
Fix the leak by deallocating the repeat_call_control under the
damon_call() failure.
This issue is discovered by sashiko [1].
CVSS Score
5.5
EPSS Score
0.0
Published
2026-04-24
In the Linux kernel, the following vulnerability has been resolved:
mm/vma: fix memory leak in __mmap_region()
commit 605f6586ecf7 ("mm/vma: do not leak memory when .mmap_prepare
swaps the file") handled the success path by skipping get_file() via
file_doesnt_need_get, but missed the error path.
When /dev/zero is mmap'd with MAP_SHARED, mmap_zero_prepare() calls
shmem_zero_setup_desc() which allocates a new shmem file to back the
mapping. If __mmap_new_vma() subsequently fails, this replacement
file is never fput()'d - the original is released by
ksys_mmap_pgoff(), but nobody releases the new one.
Add fput() for the swapped file in the error path.
Reproducible with fault injection.
FAULT_INJECTION: forcing a failure.
name failslab, interval 1, probability 0, space 0, times 1
CPU: 2 UID: 0 PID: 366 Comm: syz.7.14 Not tainted 7.0.0-rc6 #2 PREEMPT(full)
Hardware name: QEMU Ubuntu 24.04 PC v2 (i440FX + PIIX, arch_caps fix, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
Call Trace:
<TASK>
dump_stack_lvl+0x164/0x1f0
should_fail_ex+0x525/0x650
should_failslab+0xdf/0x140
kmem_cache_alloc_noprof+0x78/0x630
vm_area_alloc+0x24/0x160
__mmap_region+0xf6b/0x2660
mmap_region+0x2eb/0x3a0
do_mmap+0xc79/0x1240
vm_mmap_pgoff+0x252/0x4c0
ksys_mmap_pgoff+0xf8/0x120
__x64_sys_mmap+0x12a/0x190
do_syscall_64+0xa9/0x580
entry_SYSCALL_64_after_hwframe+0x76/0x7e
</TASK>
kmemleak: 1 new suspected memory leaks (see /sys/kernel/debug/kmemleak)
BUG: memory leak
unreferenced object 0xffff8881118aca80 (size 360):
comm "syz.7.14", pid 366, jiffies 4294913255
hex dump (first 32 bytes):
00 00 00 00 ad 4e ad de ff ff ff ff 00 00 00 00 .....N..........
ff ff ff ff ff ff ff ff c0 28 4d ae ff ff ff ff .........(M.....
backtrace (crc db0f53bc):
kmem_cache_alloc_noprof+0x3ab/0x630
alloc_empty_file+0x5a/0x1e0
alloc_file_pseudo+0x135/0x220
__shmem_file_setup+0x274/0x420
shmem_zero_setup_desc+0x9c/0x170
mmap_zero_prepare+0x123/0x140
__mmap_region+0xdda/0x2660
mmap_region+0x2eb/0x3a0
do_mmap+0xc79/0x1240
vm_mmap_pgoff+0x252/0x4c0
ksys_mmap_pgoff+0xf8/0x120
__x64_sys_mmap+0x12a/0x190
do_syscall_64+0xa9/0x580
entry_SYSCALL_64_after_hwframe+0x76/0x7e
Found by syzkaller.
CVSS Score
5.5
EPSS Score
0.0
Published
2026-04-24
In the Linux kernel, the following vulnerability has been resolved:
pmdomain: imx8mp-blk-ctrl: Keep the NOC_HDCP clock enabled
Keep the NOC_HDCP clock always enabled to fix the potential hang
caused by the NoC ADB400 port power down handshake.
CVSS Score
5.5
EPSS Score
0.0
Published
2026-04-24
In the Linux kernel, the following vulnerability has been resolved:
rxrpc: reject undecryptable rxkad response tickets
rxkad_decrypt_ticket() decrypts the RXKAD response ticket and then
parses the buffer as plaintext without checking whether
crypto_skcipher_decrypt() succeeded.
A malformed RESPONSE can therefore use a non-block-aligned ticket
length, make the decrypt operation fail, and still drive the ticket
parser with attacker-controlled bytes.
Check the decrypt result and abort the connection with RXKADBADTICKET
when ticket decryption fails.
CVSS Score
9.8
EPSS Score
0.0
Published
2026-04-24
In the Linux kernel, the following vulnerability has been resolved:
rxrpc: Only put the call ref if one was acquired
rxrpc_input_packet_on_conn() can process a to-client packet after the
current client call on the channel has already been torn down. In that
case chan->call is NULL, rxrpc_try_get_call() returns NULL and there is
no reference to drop.
The client-side implicit-end error path does not account for that and
unconditionally calls rxrpc_put_call(). This turns a protocol error
path into a kernel crash instead of rejecting the packet.
Only drop the call reference if one was actually acquired. Keep the
existing protocol error handling unchanged.
CVSS Score
7.5
EPSS Score
0.001
Published
2026-04-24
In the Linux kernel, the following vulnerability has been resolved:
rxrpc: Fix key reference count leak from call->key
When creating a client call in rxrpc_alloc_client_call(), the code obtains
a reference to the key. This is never cleaned up and gets leaked when the
call is destroyed.
Fix this by freeing call->key in rxrpc_destroy_call().
Before the patch, it shows the key reference counter elevated:
$ cat /proc/keys | grep afs@54321
1bffe9cd I--Q--i 8053480 4169w 3b010000 1000 1000 rxrpc afs@54321: ka
$
After the patch, the invalidated key is removed when the code exits:
$ cat /proc/keys | grep afs@54321
$
CVSS Score
5.5
EPSS Score
0.0
Published
2026-04-24