CVE-2026-46314
In the Linux kernel, the following vulnerability has been resolved: drm/v3d: Reject empty multisync extension to prevent infinite loop v3d_get_extensions() walks a userspace-provided singly-linked list of ioctl extensions without any bound on the chain…
Does this matter?
Lower severity and a low EPSS score (0.11%). Track it; it rarely justifies an emergency change on its own.
Description
In the Linux kernel, the following vulnerability has been resolved: drm/v3d: Reject empty multisync extension to prevent infinite loop v3d_get_extensions() walks a userspace-provided singly-linked list of ioctl extensions without any bound on the chain length. A local user can craft a self-referential extension (ext->next == &ext) with zero in_sync_count and out_sync_count, which bypasses the existing duplicate- extension guard: if (se->in_sync_count || se->out_sync_count) return -EINVAL; The guard never fires because v3d_get_multisync_post_deps() returns immediately when count is zero, leaving both fields at zero on every iteration. The result is an infinite loop in kernel context, blocking the calling thread and pegging a CPU core indefinitely. Fix this by rejecting a multisync extension where both in_sync_count and out_sync_count are zero in v3d_get_multisync_submit_deps(). An empty multisync carries no synchronization information and serves no useful purpose, so returning -EINVAL for such an extension is the correct defense against this attack vector.
- CVSS 3.1
- 5.5 MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
- EPSS
- 0.11% probability · 2th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-835
- Affected
- linux/linux kernel
- Source
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
References
- https://git.kernel.org/stable/c/309abbddeca0c12714721928a819ef45e5710998Patch
- https://git.kernel.org/stable/c/4fa42a249e8cd6ed17aea04e5695b6e9001f2433Patch
- https://git.kernel.org/stable/c/9c5164781cb388d219d8f49fa0f0b04cf86ad544Patch
- https://git.kernel.org/stable/c/fb44d589bf3148e13452185a6e772a7efbf2d684Patch
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.