High · published December 16, 2025
In the Linux kernel, the following vulnerability has been resolved:
drm/radeon: Remove calls to drm_put_dev()
Since the allocation of the drivers main structure was changed to
devm_drm_dev_alloc() drm_put_dev()'ing to trigger it to be free'd
should be done by devres.
However, drm_put_dev() is still in the probe error and device remove
paths. When the driver fails to probe warnings like the following are
shown because devres is trying to drm_put_dev() after the driver
already did it.
[ 5.642230] radeon 0000:01:05.0: probe with driver radeon failed with error -22
[ 5.649605] ------------[ cut here ]------------
[ 5.649607] refcount_t: underflow; use-after-free.
[ 5.649620] WARNING: CPU: 0 PID: 357 at lib/refcount.c:28 refcount_warn_saturate+0xbe/0x110
(cherry picked from commit 3eb8c0b4c091da0a623ade0d3ee7aa4a93df1ea4)