Description

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)

References 3

• git.kernel.org https://git.kernel.org/stable/c/2fa41445d8c98f2a65503c373796466496edc0e7
• git.kernel.org https://git.kernel.org/stable/c/745bae76acdd71709773c129a69deca01036250b
• git.kernel.org https://git.kernel.org/stable/c/ec18f6b2c743cc471b2539ddb5caed20a012e640

Remediation