CVE-2026-72091: accel/amdxdna: reject user command submission without a command BO

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

From: Greg Kroah-Hartman <gregkh@kernel.org>

Description
===========

In the Linux kernel, the following vulnerability has been resolved:

accel/amdxdna: reject user command submission without a command BO

amdxdna_drm_submit_execbuf() passes the user-supplied command BO handle
straight into amdxdna_cmd_submit() with drv_cmd == NULL. When the handle
is AMDXDNA_INVALID_BO_HANDLE (0), the block that fetches job->cmd_bo is
skipped, leaving it NULL, and no check rejects it on the user path (the
!job->cmd_bo guard lives inside the != INVALID branch).

The job is then armed and pushed to the DRM scheduler.
aie2_sched_job_run() takes the drv_cmd == NULL path and calls
amdxdna_cmd_set_state(job->cmd_bo) -> amdxdna_gem_vmap(NULL) ->
to_gobj(NULL)->dev, a NULL pointer dereference in the drm_sched worker.
A process with access to the accel node on a system with a probed AMD NPU
can trigger a kernel oops with a single AMDXDNA_EXEC_CMD ioctl
(cmd_handles = 0).

Only internal driver commands (SYNC_DEBUG_BO / ATTACH_DEBUG_BO)
legitimately pass AMDXDNA_INVALID_BO_HANDLE, and they always set drv_cmd.
Reject the invalid handle for user submissions (drv_cmd == NULL) at the
submit choke point so every user path is covered.

Found by 0sec automated security-research tooling (https://0sec.ai).

The Linux kernel CVE team has assigned CVE-2026-72091 to this issue.


Affected and fixed versions
===========================

	Issue introduced in 6.14 with commit aac243092b707bb3018e951d470cc1a9bcbaba6c and fixed in 7.1.5 with commit fff6509d976f6fae423a5236391ccdbd7e0e9f06
	Issue introduced in 6.14 with commit aac243092b707bb3018e951d470cc1a9bcbaba6c and fixed in 7.2-rc4 with commit 261c1fe3327ad24508f54552c6366e3e4db82c15

Please see https://www.kernel.org for a full list of currently supported
kernel versions by the kernel community.

Unaffected versions might change over time as fixes are backported to
older supported kernel versions.  The official CVE entry at
	https://cve.org/CVERecord/?id=CVE-2026-72091
will be updated if fixes are backported, please check that for the most
up to date information about this issue.


Affected files
==============

The file(s) affected by this issue are:
	drivers/accel/amdxdna/amdxdna_ctx.c


Mitigation
==========

The Linux kernel CVE team recommends that you update to the latest
stable kernel version for this, and many other bugfixes.  Individual
changes are never tested alone, but rather are part of a larger kernel
release.  Cherry-picking individual commits is not recommended or
supported by the Linux kernel community at all.  If however, updating to
the latest release is impossible, the individual changes to resolve this
issue can be found at these commits:
	https://git.kernel.org/stable/c/fff6509d976f6fae423a5236391ccdbd7e0e9f06
	https://git.kernel.org/stable/c/261c1fe3327ad24508f54552c6366e3e4db82c15