Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
ksmbd: Compare MACs in constant time
To prevent timing attacks, MAC comparisons need to be constant-time.
Replace the memcmp() with the correct function, crypto_memneq().
CVSS Score
7.4
EPSS Score
0.0
Published
2026-03-25
In the Linux kernel, the following vulnerability has been resolved:
net: usb: kalmia: validate USB endpoints
The kalmia driver should validate that the device it is probing has the
proper number and types of USB endpoints it is expecting before it binds
to it. If a malicious device were to not have the same urbs the driver
will crash later on when it blindly accesses these endpoints.
CVSS Score
5.5
EPSS Score
0.0
Published
2026-03-25
In the Linux kernel, the following vulnerability has been resolved:
drm/client: Do not destroy NULL modes
'modes' in drm_client_modeset_probe may fail to kcalloc. If this
occurs, we jump to 'out', calling modes_destroy on it, which
dereferences it. This may result in a NULL pointer dereference in the
error case. Prevent that.
CVSS Score
5.5
EPSS Score
0.0
Published
2026-03-25
In the Linux kernel, the following vulnerability has been resolved:
ata: libata: cancel pending work after clearing deferred_qc
Syzbot reported a WARN_ON() in ata_scsi_deferred_qc_work(), caused by
ap->ops->qc_defer() returning non-zero before issuing the deferred qc.
ata_scsi_schedule_deferred_qc() is called during each command completion.
This function will check if there is a deferred QC, and if
ap->ops->qc_defer() returns zero, meaning that it is possible to queue the
deferred qc at this time (without being deferred), then it will queue the
work which will issue the deferred qc.
Once the work get to run, which can potentially be a very long time after
the work was scheduled, there is a WARN_ON() if ap->ops->qc_defer() returns
non-zero.
While we hold the ap->lock both when assigning and clearing deferred_qc,
and the work itself holds the ap->lock, the code currently does not cancel
the work after clearing the deferred qc.
This means that the following scenario can happen:
1) One or several NCQ commands are queued.
2) A non-NCQ command is queued, gets stored in ap->deferred_qc.
3) Last NCQ command gets completed, work is queued to issue the deferred
qc.
4) Timeout or error happens, ap->deferred_qc is cleared. The queued work is
currently NOT canceled.
5) Port is reset.
6) One or several NCQ commands are queued.
7) A non-NCQ command is queued, gets stored in ap->deferred_qc.
8) Work is finally run. Yet at this time, there is still NCQ commands in
flight.
The work in 8) really belongs to the non-NCQ command in 2), not to the
non-NCQ command in 7). The reason why the work is executed when it is not
supposed to, is because it was never canceled when ap->deferred_qc was
cleared in 4). Thus, ensure that we always cancel the work after clearing
ap->deferred_qc.
Another potential fix would have been to let ata_scsi_deferred_qc_work() do
nothing if ap->ops->qc_defer() returns non-zero. However, canceling the
work when clearing ap->deferred_qc seems slightly more logical, as we hold
the ap->lock when clearing ap->deferred_qc, so we know that the work cannot
be holding the lock. (The function could be waiting for the lock, but that
is okay since it will do nothing if ap->deferred_qc is not set.)
CVSS Score
5.5
EPSS Score
0.0
Published
2026-03-25
In the Linux kernel, the following vulnerability has been resolved:
drbd: fix "LOGIC BUG" in drbd_al_begin_io_nonblock()
Even though we check that we "should" be able to do lc_get_cumulative()
while holding the device->al_lock spinlock, it may still fail,
if some other code path decided to do lc_try_lock() with bad timing.
If that happened, we logged "LOGIC BUG for enr=...",
but still did not return an error.
The rest of the code now assumed that this request has references
for the relevant activity log extents.
The implcations are that during an active resync, mutual exclusivity of
resync versus application IO is not guaranteed. And a potential crash
at this point may not realizs that these extents could have been target
of in-flight IO and would need to be resynced just in case.
Also, once the request completes, it will give up activity log references it
does not even hold, which will trigger a BUG_ON(refcnt == 0) in lc_put().
Fix:
Do not crash the kernel for a condition that is harmless during normal
operation: also catch "e->refcnt == 0", not only "e == NULL"
when being noisy about "al_complete_io() called on inactive extent %u\n".
And do not try to be smart and "guess" whether something will work, then
be surprised when it does not.
Deal with the fact that it may or may not work. If it does not, remember a
possible "partially in activity log" state (only possible for requests that
cross extent boundaries), and return an error code from
drbd_al_begin_io_nonblock().
A latter call for the same request will then resume from where we left off.
CVSS Score
5.5
EPSS Score
0.0
Published
2026-03-25
In the Linux kernel, the following vulnerability has been resolved:
can: mcp251x: fix deadlock in error path of mcp251x_open
The mcp251x_open() function call free_irq() in its error path with the
mpc_lock mutex held. But if an interrupt already occurred the
interrupt handler will be waiting for the mpc_lock and free_irq() will
deadlock waiting for the handler to finish.
This issue is similar to the one fixed in commit 7dd9c26bd6cf ("can:
mcp251x: fix deadlock if an interrupt occurs during mcp251x_open") but
for the error path.
To solve this issue move the call to free_irq() after the lock is
released. Setting `priv->force_quit = 1` beforehand ensure that the IRQ
handler will exit right away once it acquired the lock.
CVSS Score
5.5
EPSS Score
0.0
Published
2026-03-25
In the Linux kernel, the following vulnerability has been resolved:
drm/amdgpu: Fix error handling in slot reset
If the device has not recovered after slot reset is called, it goes to
out label for error handling. There it could make decision based on
uninitialized hive pointer and could result in accessing an uninitialized
list.
Initialize the list and hive properly so that it handles the error
situation and also releases the reset domain lock which is acquired
during error_detected callback.
(cherry picked from commit bb71362182e59caa227e4192da5a612b09349696)
CVSS Score
5.5
EPSS Score
0.0
Published
2026-03-25
In the Linux kernel, the following vulnerability has been resolved:
bpf: Fix stack-out-of-bounds write in devmap
get_upper_ifindexes() iterates over all upper devices and writes their
indices into an array without checking bounds.
Also the callers assume that the max number of upper devices is
MAX_NEST_DEV and allocate excluded_devices[1+MAX_NEST_DEV] on the stack,
but that assumption is not correct and the number of upper devices could
be larger than MAX_NEST_DEV (e.g., many macvlans), causing a
stack-out-of-bounds write.
Add a max parameter to get_upper_ifindexes() to avoid the issue.
When there are too many upper devices, return -EOVERFLOW and abort the
redirect.
To reproduce, create more than MAX_NEST_DEV(8) macvlans on a device with
an XDP program attached using BPF_F_BROADCAST | BPF_F_EXCLUDE_INGRESS.
Then send a packet to the device to trigger the XDP redirect path.
CVSS Score
7.8
EPSS Score
0.0
Published
2026-03-25
In the Linux kernel, the following vulnerability has been resolved:
nvme: fix admin queue leak on controller reset
When nvme_alloc_admin_tag_set() is called during a controller reset,
a previous admin queue may still exist. Release it properly before
allocating a new one to avoid orphaning the old queue.
This fixes a regression introduced by commit 03b3bcd319b3 ("nvme: fix
admin request_queue lifetime").
CVSS Score
5.5
EPSS Score
0.0
Published
2026-03-25
In the Linux kernel, the following vulnerability has been resolved:
cxl: Fix race of nvdimm_bus object when creating nvdimm objects
Found issue during running of cxl-translate.sh unit test. Adding a 3s
sleep right before the test seems to make the issue reproduce fairly
consistently. The cxl_translate module has dependency on cxl_acpi and
causes orphaned nvdimm objects to reprobe after cxl_acpi is removed.
The nvdimm_bus object is registered by the cxl_nvb object when
cxl_acpi_probe() is called. With the nvdimm_bus object missing,
__nd_device_register() will trigger NULL pointer dereference when
accessing the dev->parent that points to &nvdimm_bus->dev.
[ 192.884510] BUG: kernel NULL pointer dereference, address: 000000000000006c
[ 192.895383] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS edk2-20250812-19.fc42 08/12/2025
[ 192.897721] Workqueue: cxl_port cxl_bus_rescan_queue [cxl_core]
[ 192.899459] RIP: 0010:kobject_get+0xc/0x90
[ 192.924871] Call Trace:
[ 192.925959] <TASK>
[ 192.926976] ? pm_runtime_init+0xb9/0xe0
[ 192.929712] __nd_device_register.part.0+0x4d/0xc0 [libnvdimm]
[ 192.933314] __nvdimm_create+0x206/0x290 [libnvdimm]
[ 192.936662] cxl_nvdimm_probe+0x119/0x1d0 [cxl_pmem]
[ 192.940245] cxl_bus_probe+0x1a/0x60 [cxl_core]
[ 192.943349] really_probe+0xde/0x380
This patch also relies on the previous change where
devm_cxl_add_nvdimm_bridge() is called from drivers/cxl/pmem.c instead
of drivers/cxl/core.c to ensure the dependency of cxl_acpi on cxl_pmem.
1. Set probe_type of cxl_nvb to PROBE_FORCE_SYNCHRONOUS to ensure the
driver is probed synchronously when add_device() is called.
2. Add a check in __devm_cxl_add_nvdimm_bridge() to ensure that the
cxl_nvb driver is attached during cxl_acpi_probe().
3. Take the cxl_root uport_dev lock and the cxl_nvb->dev lock in
devm_cxl_add_nvdimm() before checking nvdimm_bus is valid.
4. Set cxl_nvdimm flag to CXL_NVD_F_INVALIDATED so cxl_nvdimm_probe()
will exit with -EBUSY.
The removal of cxl_nvdimm devices should prevent any orphaned devices
from probing once the nvdimm_bus is gone.
[ dj: Fixed 0-day reported kdoc issue. ]
[ dj: Fix cxl_nvb reference leak on error. Gregory (kreview-0811365) ]
CVSS Score
4.7
EPSS Score
0.0
Published
2026-03-25