Linux: >> Linux Kernel >> 4.11.5 Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
e1000/e1000e: Fix leak in DMA error cleanup
If an error is encountered while mapping TX buffers, the driver should
unmap any buffers already mapped for that skb.
Because count is incremented after a successful mapping, it will always
match the correct number of unmappings needed when dma_error is reached.
Decrementing count before the while loop in dma_error causes an
off-by-one error. If any mapping was successful before an unsuccessful
mapping, exactly one DMA mapping would leak.
In these commits, a faulty while condition caused an infinite loop in
dma_error:
Commit 03b1320dfcee ("e1000e: remove use of skb_dma_map from e1000e
driver")
Commit 602c0554d7b0 ("e1000: remove use of skb_dma_map from e1000 driver")
Commit c1fa347f20f1 ("e1000/e1000e/igb/igbvf/ixgb/ixgbe: Fix tests of
unsigned in *_tx_map()") fixed the infinite loop, but introduced the
off-by-one error.
This issue may still exist in the igbvf driver, but I did not address it
in this patch.
CVSS Score
5.5
EPSS Score
0.0
Published
2026-05-08
In the Linux kernel, the following vulnerability has been resolved:
usb: yurex: fix race in probe
The bbu member of the descriptor must be set to the value
standing for uninitialized values before the URB whose
completion handler sets bbu is submitted. Otherwise there is
a window during which probing can overwrite already retrieved
data.
CVSS Score
4.7
EPSS Score
0.0
Published
2026-05-08
In the Linux kernel, the following vulnerability has been resolved:
usb: gadget: f_ncm: Fix net_device lifecycle with device_move
The network device outlived its parent gadget device during
disconnection, resulting in dangling sysfs links and null pointer
dereference problems.
A prior attempt to solve this by removing SET_NETDEV_DEV entirely [1]
was reverted due to power management ordering concerns and a NO-CARRIER
regression.
A subsequent attempt to defer net_device allocation to bind [2] broke
1:1 mapping between function instance and network device, making it
impossible for configfs to report the resolved interface name. This
results in a regression where the DHCP server fails on pmOS.
Use device_move to reparent the net_device between the gadget device and
/sys/devices/virtual/ across bind/unbind cycles. This preserves the
network interface across USB reconnection, allowing the DHCP server to
retain their binding.
Introduce gether_attach_gadget()/gether_detach_gadget() helpers and use
__free(detach_gadget) macro to undo attachment on bind failure. The
bind_count ensures device_move executes only on the first bind.
[1] https://lore.kernel.org/lkml/f2a4f9847617a0929d62025748384092e5f35cce.camel@crapouillou.net/
[2] https://lore.kernel.org/linux-usb/795ea759-7eaf-4f78-81f4-01ffbf2d7961@ixit.cz/
CVSS Score
5.5
EPSS Score
0.0
Published
2026-05-08
In the Linux kernel, the following vulnerability has been resolved:
usb: gadget: f_tcm: Fix NULL pointer dereferences in nexus handling
The `tpg->tpg_nexus` pointer in the USB Target driver is dynamically
managed and tied to userspace configuration via ConfigFS. It can be
NULL if the USB host sends requests before the nexus is fully
established or immediately after it is dropped.
Currently, functions like `bot_submit_command()` and the data
transfer paths retrieve `tv_nexus = tpg->tpg_nexus` and immediately
dereference `tv_nexus->tvn_se_sess` without any validation. If a
malicious or misconfigured USB host sends a BOT (Bulk-Only Transport)
command during this race window, it triggers a NULL pointer
dereference, leading to a kernel panic (local DoS).
This exposes an inconsistent API usage within the module, as peer
functions like `usbg_submit_command()` and `bot_send_bad_response()`
correctly implement a NULL check for `tv_nexus` before proceeding.
Fix this by bringing consistency to the nexus handling. Add the
missing `if (!tv_nexus)` checks to the vulnerable BOT command and
request processing paths, aborting the command gracefully with an
error instead of crashing the system.
CVSS Score
5.5
EPSS Score
0.0
Published
2026-05-08
In the Linux kernel, the following vulnerability has been resolved:
usb: image: mdc800: kill download URB on timeout
mdc800_device_read() submits download_urb and waits for completion.
If the timeout fires and the device has not responded, the function
returns without killing the URB, leaving it active.
A subsequent read() resubmits the same URB while it is still
in-flight, triggering the WARN in usb_submit_urb():
"URB submitted while active"
Check the return value of wait_event_timeout() and kill the URB if
it indicates timeout, ensuring the URB is complete before its status
is inspected or the URB is resubmitted.
Similar to
- commit 372c93131998 ("USB: yurex: fix control-URB timeout handling")
- commit b98d5000c505 ("media: rc: iguanair: handle timeouts")
CVSS Score
5.5
EPSS Score
0.0
Published
2026-05-08
In the Linux kernel, the following vulnerability has been resolved:
usb: renesas_usbhs: fix use-after-free in ISR during device removal
In usbhs_remove(), the driver frees resources (including the pipe array)
while the interrupt handler (usbhs_interrupt) is still registered. If an
interrupt fires after usbhs_pipe_remove() but before the driver is fully
unbound, the ISR may access freed memory, causing a use-after-free.
Fix this by calling devm_free_irq() before freeing resources. This ensures
the interrupt handler is both disabled and synchronized (waits for any
running ISR to complete) before usbhs_pipe_remove() is called.
CVSS Score
7.8
EPSS Score
0.0
Published
2026-05-08
In the Linux kernel, the following vulnerability has been resolved:
usb: class: cdc-wdm: fix reordering issue in read code path
Quoting the bug report:
Due to compiler optimization or CPU out-of-order execution, the
desc->length update can be reordered before the memmove. If this
happens, wdm_read() can see the new length and call copy_to_user() on
uninitialized memory. This also violates LKMM data race rules [1].
Fix it by using WRITE_ONCE and memory barriers.
CVSS Score
7.1
EPSS Score
0.0
Published
2026-05-08
In the Linux kernel, the following vulnerability has been resolved:
USB: core: Limit the length of unkillable synchronous timeouts
The usb_control_msg(), usb_bulk_msg(), and usb_interrupt_msg() APIs in
usbcore allow unlimited timeout durations. And since they use
uninterruptible waits, this leaves open the possibility of hanging a
task for an indefinitely long time, with no way to kill it short of
unplugging the target device.
To prevent this sort of problem, enforce a maximum limit on the length
of these unkillable timeouts. The limit chosen here, somewhat
arbitrarily, is 60 seconds. On many systems (although not all) this
is short enough to avoid triggering the kernel's hung-task detector.
In addition, clear up the ambiguity of negative timeout values by
treating them the same as 0, i.e., using the maximum allowed timeout.
CVSS Score
5.5
EPSS Score
0.0
Published
2026-05-08
In the Linux kernel, the following vulnerability has been resolved:
powerpc, perf: Check that current->mm is alive before getting user callchain
It may happen that mm is already released, which leads to kernel panic.
This adds the NULL check for current->mm, similarly to
commit 20afc60f892d ("x86, perf: Check that current->mm is alive before getting user callchain").
I was getting this panic when running a profiling BPF program
(profile.py from bcc-tools):
[26215.051935] Kernel attempted to read user page (588) - exploit attempt? (uid: 0)
[26215.051950] BUG: Kernel NULL pointer dereference on read at 0x00000588
[26215.051952] Faulting instruction address: 0xc00000000020fac0
[26215.051957] Oops: Kernel access of bad area, sig: 11 [#1]
[...]
[26215.052049] Call Trace:
[26215.052050] [c000000061da6d30] [c00000000020fc10] perf_callchain_user_64+0x2d0/0x490 (unreliable)
[26215.052054] [c000000061da6dc0] [c00000000020f92c] perf_callchain_user+0x1c/0x30
[26215.052057] [c000000061da6de0] [c0000000005ab2a0] get_perf_callchain+0x100/0x360
[26215.052063] [c000000061da6e70] [c000000000573bc8] bpf_get_stackid+0x88/0xf0
[26215.052067] [c000000061da6ea0] [c008000000042258] bpf_prog_16d4ab9ab662f669_do_perf_event+0xf8/0x274
[...]
In addition, move storing the top-level stack entry to generic
perf_callchain_user to make sure the top-evel entry is always captured,
even if current->mm is NULL.
[Maddy: fixed message to avoid checkpatch format style error]
CVSS Score
5.5
EPSS Score
0.0
Published
2026-05-08
In the Linux kernel, the following vulnerability has been resolved:
libceph: Fix potential out-of-bounds access in ceph_handle_auth_reply()
This patch fixes an out-of-bounds access in ceph_handle_auth_reply()
that can be triggered by a message of type CEPH_MSG_AUTH_REPLY. In
ceph_handle_auth_reply(), the value of the payload_len field of such a
message is stored in a variable of type int. A value greater than
INT_MAX leads to an integer overflow and is interpreted as a negative
value. This leads to decrementing the pointer address by this value and
subsequently accessing it because ceph_decode_need() only checks that
the memory access does not exceed the end address of the allocation.
This patch fixes the issue by changing the data type of payload_len to
u32. Additionally, the data type of result_msg_len is changed to u32,
as it is also a variable holding a non-negative length.
Also, an additional layer of sanity checks is introduced, ensuring that
directly after reading it from the message, payload_len and
result_msg_len are not greater than the overall segment length.
BUG: KASAN: slab-out-of-bounds in ceph_handle_auth_reply+0x642/0x7a0 [libceph]
Read of size 4 at addr ffff88811404df14 by task kworker/20:1/262
CPU: 20 UID: 0 PID: 262 Comm: kworker/20:1 Not tainted 6.19.2 #5 PREEMPT(voluntary)
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
Workqueue: ceph-msgr ceph_con_workfn [libceph]
Call Trace:
<TASK>
dump_stack_lvl+0x76/0xa0
print_report+0xd1/0x620
? __pfx__raw_spin_lock_irqsave+0x10/0x10
? kasan_complete_mode_report_info+0x72/0x210
kasan_report+0xe7/0x130
? ceph_handle_auth_reply+0x642/0x7a0 [libceph]
? ceph_handle_auth_reply+0x642/0x7a0 [libceph]
__asan_report_load_n_noabort+0xf/0x20
ceph_handle_auth_reply+0x642/0x7a0 [libceph]
mon_dispatch+0x973/0x23d0 [libceph]
? apparmor_socket_recvmsg+0x6b/0xa0
? __pfx_mon_dispatch+0x10/0x10 [libceph]
? __kasan_check_write+0x14/0x30i
? mutex_unlock+0x7f/0xd0
? __pfx_mutex_unlock+0x10/0x10
? __pfx_do_recvmsg+0x10/0x10 [libceph]
ceph_con_process_message+0x1f1/0x650 [libceph]
process_message+0x1e/0x450 [libceph]
ceph_con_v2_try_read+0x2e48/0x6c80 [libceph]
? __pfx_ceph_con_v2_try_read+0x10/0x10 [libceph]
? save_fpregs_to_fpstate+0xb0/0x230
? raw_spin_rq_unlock+0x17/0xa0
? finish_task_switch.isra.0+0x13b/0x760
? __switch_to+0x385/0xda0
? __kasan_check_write+0x14/0x30
? mutex_lock+0x8d/0xe0
? __pfx_mutex_lock+0x10/0x10
ceph_con_workfn+0x248/0x10c0 [libceph]
process_one_work+0x629/0xf80
? __kasan_check_write+0x14/0x30
worker_thread+0x87f/0x1570
? __pfx__raw_spin_lock_irqsave+0x10/0x10
? __pfx_try_to_wake_up+0x10/0x10
? kasan_print_address_stack_frame+0x1f7/0x280
? __pfx_worker_thread+0x10/0x10
kthread+0x396/0x830
? __pfx__raw_spin_lock_irq+0x10/0x10
? __pfx_kthread+0x10/0x10
? __kasan_check_write+0x14/0x30
? recalc_sigpending+0x180/0x210
? __pfx_kthread+0x10/0x10
ret_from_fork+0x3f7/0x610
? __pfx_ret_from_fork+0x10/0x10
? __switch_to+0x385/0xda0
? __pfx_kthread+0x10/0x10
ret_from_fork_asm+0x1a/0x30
</TASK>
[ idryomov: replace if statements with ceph_decode_need() for
payload_len and result_msg_len ]
CVSS Score
9.1
EPSS Score
0.001
Published
2026-05-08