Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
ublk: Validate SQE128 flag before accessing the cmd
ublk_ctrl_cmd_dump() accesses (header *)sqe->cmd before
IO_URING_F_SQE128 flag check. This could cause out of boundary memory
access.
Move the SQE128 flag check earlier in ublk_ctrl_uring_cmd() to return
-EINVAL immediately if the flag is not set.
CVSS Score
5.5
EPSS Score
0.002
Published
2026-05-27
In the Linux kernel, the following vulnerability has been resolved:
drm/amdgpu: Fix memory leak in amdgpu_acpi_enumerate_xcc()
In amdgpu_acpi_enumerate_xcc(), if amdgpu_acpi_dev_init() returns -ENOMEM,
the function returns directly without releasing the allocated xcc_info,
resulting in a memory leak.
Fix this by ensuring that xcc_info is properly freed in the error paths.
Compile tested only. Issue found using a prototype static analysis tool
and code review.
CVSS Score
5.5
EPSS Score
0.002
Published
2026-05-27
In the Linux kernel, the following vulnerability has been resolved:
ext4: fix memory leak in ext4_ext_shift_extents()
In ext4_ext_shift_extents(), if the extent is NULL in the while loop, the
function returns immediately without releasing the path obtained via
ext4_find_extent(), leading to a memory leak.
Fix this by jumping to the out label to ensure the path is properly
released.
CVSS Score
5.5
EPSS Score
0.002
Published
2026-05-27
In the Linux kernel, the following vulnerability has been resolved:
hwrng: core - use RCU and work_struct to fix race condition
Currently, hwrng_fill is not cleared until the hwrng_fillfn() thread
exits. Since hwrng_unregister() reads hwrng_fill outside the rng_mutex
lock, a concurrent hwrng_unregister() may call kthread_stop() again on
the same task.
Additionally, if hwrng_unregister() is called immediately after
hwrng_register(), the stopped thread may have never been executed. Thus,
hwrng_fill remains dirty even after hwrng_unregister() returns. In this
case, subsequent calls to hwrng_register() will fail to start new
threads, and hwrng_unregister() will call kthread_stop() on the same
freed task. In both cases, a use-after-free occurs:
refcount_t: addition on 0; use-after-free.
WARNING: ... at lib/refcount.c:25 refcount_warn_saturate+0xec/0x1c0
Call Trace:
kthread_stop+0x181/0x360
hwrng_unregister+0x288/0x380
virtrng_remove+0xe3/0x200
This patch fixes the race by protecting the global hwrng_fill pointer
inside the rng_mutex lock, so that hwrng_fillfn() thread is stopped only
once, and calls to kthread_run() and kthread_stop() are serialized
with the lock held.
To avoid deadlock in hwrng_fillfn() while being stopped with the lock
held, we convert current_rng to RCU, so that get_current_rng() can read
current_rng without holding the lock. To remove the lock from put_rng(),
we also delay the actual cleanup into a work_struct.
Since get_current_rng() no longer returns ERR_PTR values, the IS_ERR()
checks are removed from its callers.
With hwrng_fill protected by the rng_mutex lock, hwrng_fillfn() can no
longer clear hwrng_fill itself. Therefore, if hwrng_fillfn() returns
directly after current_rng is dropped, kthread_stop() would be called on
a freed task_struct later. To fix this, hwrng_fillfn() calls schedule()
now to keep the task alive until being stopped. The kthread_stop() call
is also moved from hwrng_unregister() to drop_current_rng(), ensuring
kthread_stop() is called on all possible paths where current_rng becomes
NULL, so that the thread would not wait forever.
CVSS Score
4.7
EPSS Score
0.001
Published
2026-05-27
In the Linux kernel, the following vulnerability has been resolved:
crypto: starfive - Fix memory leak in starfive_aes_aead_do_one_req()
The starfive_aes_aead_do_one_req() function allocates rctx->adata with
kzalloc() but fails to free it if sg_copy_to_buffer() or
starfive_aes_hw_init() fails, which lead to memory leaks.
Since rctx->adata is unconditionally freed after the write_adata
operations, ensure consistent cleanup by freeing the allocation in these
earlier error paths as well.
Compile tested only. Issue found using a prototype static analysis tool
and code review.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-05-27
In the Linux kernel, the following vulnerability has been resolved:
bpf: Fix a potential use-after-free of BTF object
Refcounting in the check_pseudo_btf_id() function is incorrect:
the __check_pseudo_btf_id() function might get called with a zero
refcounted btf. Fix this, and patch related code accordingly.
v3: rephrase a comment (AI)
v2: fix a refcount leak introduced in v1 (AI)
CVSS Score
7.8
EPSS Score
0.001
Published
2026-05-27
In the Linux kernel, the following vulnerability has been resolved:
eth: fbnic: Add validation for MTU changes
Increasing the MTU beyond the HDS threshold causes the hardware to
fragment packets across multiple buffers. If a single-buffer XDP program
is attached, the driver will drop all multi-frag frames. While we can't
prevent a remote sender from sending non-TCP packets larger than the MTU,
this will prevent users from inadvertently breaking new TCP streams.
Traditionally, drivers supported XDP with MTU less than 4Kb
(packet per page). Fbnic currently prevents attaching XDP when MTU is too high.
But it does not prevent increasing MTU after XDP is attached.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-05-27
In the Linux kernel, the following vulnerability has been resolved:
md/raid5: fix IO hang with degraded array with llbitmap
When llbitmap bit state is still unwritten, any new write should force
rcw, as bitmap_ops->blocks_synced() is checked in handle_stripe_dirtying().
However, later the same check is missing in need_this_block(), causing
stripe to deadloop during handling because handle_stripe() will decide
to go to handle_stripe_fill(), meanwhile need_this_block() always return
0 and nothing is handled.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-05-27
In the Linux kernel, the following vulnerability has been resolved:
fbdev: au1200fb: Fix a memory leak in au1200fb_drv_probe()
In au1200fb_drv_probe(), when platform_get_irq fails(), it directly
returns from the function with an error code, which causes a memory
leak.
Replace it with a goto label to ensure proper cleanup.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-05-27
In the Linux kernel, the following vulnerability has been resolved:
iommu/vt-d: Clear Present bit before tearing down context entry
When tearing down a context entry, the current implementation zeros the
entire 128-bit entry using multiple 64-bit writes. This creates a window
where the hardware can fetch a "torn" entry — where some fields are
already zeroed while the 'Present' bit is still set — leading to
unpredictable behavior or spurious faults.
While x86 provides strong write ordering, the compiler may reorder writes
to the two 64-bit halves of the context entry. Even without compiler
reordering, the hardware fetch is not guaranteed to be atomic with
respect to multiple CPU writes.
Align with the "Guidance to Software for Invalidations" in the VT-d spec
(Section 6.5.3.3) by implementing the recommended ownership handshake:
1. Clear only the 'Present' (P) bit of the context entry first to
signal the transition of ownership from hardware to software.
2. Use dma_wmb() to ensure the cleared bit is visible to the IOMMU.
3. Perform the required cache and context-cache invalidation to ensure
hardware no longer has cached references to the entry.
4. Fully zero out the entry only after the invalidation is complete.
Also, add a dma_wmb() to context_set_present() to ensure the entry
is fully initialized before the 'Present' bit becomes visible.
CVSS Score
7.5
EPSS Score
0.001
Published
2026-05-27