CVEvulnerability
CVE-2026-74683
- Status
- Received
- Published
- 2026-08-22
- Last modified
- 2026-10-14
- Assigner
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Description
In the Linux kernel, the following vulnerability has been resolved:
Input: evdev - sanitize event type index when fetching event masks
The user-supplied event type index passed to EVIOCGMASK / EVIOCSMASK
ioctls is used to index the static counts array in evdev_get_mask_cnt()
and client evmasks array in evdev_get_mask().
While the event type is architecturally bounded by EV_CNT, speculative
execution may mispredict bounds checks and perform out-of-bounds loads.
Sanitize the event type index in evdev_get_mask_cnt() branchlessly using
array_index_mask_nospec(). This clamps the index to 0 for safe array
access and forces the returned count to 0 speculatively when the index
is out of bounds.
We do not need additional array_index_nospec() calls in evdev_get_mask()
because evdev_get_mask_cnt() speculatively forces the count (and
resulting xfer_size) to 0 for out-of-bounds types, preventing any
speculative memory access to client evmasks array.
References
- https://git.kernel.org/stable/c/3abd29c61d2ef37c4102cf755b18be53bb9dbea6 git.kernel.org
- https://git.kernel.org/stable/c/4034ef247a9dde3f56660b01f0c3280dac6b1274 git.kernel.org
- https://git.kernel.org/stable/c/433913b4a92214d76e9f0c03ad9128fec943d5f8 git.kernel.org
- https://git.kernel.org/stable/c/5db341189bb7ff041d570dbe36ecca7e32913927 git.kernel.org
- https://git.kernel.org/stable/c/810e1883d4815f29c30d900ad7333d03cc2515d1 git.kernel.org
- https://git.kernel.org/stable/c/c79b08d8fa230871a3634e34a66e591ac2d084ef git.kernel.org
- https://git.kernel.org/stable/c/f27fa9b39f925d26e034a1f382cb45523138f4ae git.kernel.org
- https://git.kernel.org/stable/c/f3fc329acad9a71b3c077237cbac20670d2358c8 git.kernel.org