CVE-2022-49490 Information

Description

In the Linux kernel the following vulnerability has been resolved:

drm/msm/mdp5: Return error code in mdp5_pipe_release when deadlock is detected

mdp5_get_global_state runs the risk of hitting a -EDEADLK when acquiring the modeset lock but currently mdp5_pipe_release doesn’t check for if an error is returned. Because of this there is a possibility of mdp5_pipe_release hitting a NULL dereference error.

To avoid this let’s have mdp5_pipe_release check if mdp5_get_global_state returns an error and propogate that error.

Changes since v1:

• Separated declaration and initialization of new_state to avoid compiler warning
• Fixed some spelling mistakes in commit message

Changes since v2:

• Return 0 in case where hwpipe is NULL as this is considered normal behavior
• Added 2nd patch in series to fix a similar NULL dereference issue in mdp5_mixer_release

Patchwork: https://patchwork.freedesktop.org/patch/485179/

Reference

https://git.kernel.org/stable/c/04bef5f1ba8ea6d7c1c8f5f65e0395c62db59cb8 https://git.kernel.org/stable/c/19964dfb39bda4d7716a71009488f0668ecbcf52 https://git.kernel.org/stable/c/33dc5aac46e0fad8f5eb193e5906ed0eb6b66ceb https://git.kernel.org/stable/c/49dc28b4b2e28ef7564e355c91487996c1cbebd7 https://git.kernel.org/stable/c/776f5c58bfe16cf322d71eeed3c5dda1eeac7e6b https://git.kernel.org/stable/c/b2aa2c4efe93e2580d6a8774b04fe2b99756a322 https://git.kernel.org/stable/c/d59be579fa932c46b908f37509f319cbd4ca9a68