Bug 1222552 (CVE-2024-26729)

Summary: VUL-0: CVE-2024-26729: kernel: drm/amd/display: Fix potential null pointer dereference in dc_dmub_srv
Product: [Novell Products] SUSE Security Incidents Reporter: SMASH SMASH <smash_bz>
Component: IncidentsAssignee: Security Team bot <security-team>
Status: RESOLVED FIXED QA Contact: Security Team bot <security-team>
Severity: Normal    
Priority: P3 - Medium CC: rfrohl, vasant.karasulli
Version: unspecified   
Target Milestone: ---   
Hardware: Other   
OS: Other   
URL: https://smash.suse.de/issue/400222/
Whiteboard: CVSSv3.1:SUSE:CVE-2024-26729:5.5:(AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H)
Found By: Security Response Team Services Priority:
Business Priority: Blocker: ---
Marketing QA Status: --- IT Deployment: ---

Description SMASH SMASH 2024-04-09 12:10:24 UTC 
In the Linux kernel, the following vulnerability has been resolved:

drm/amd/display: Fix potential null pointer dereference in dc_dmub_srv

Fixes potential null pointer dereference warnings in the
dc_dmub_srv_cmd_list_queue_execute() and dc_dmub_srv_is_hw_pwr_up()
functions.

In both functions, the 'dc_dmub_srv' variable was being dereferenced
before it was checked for null. This could lead to a null pointer
dereference if 'dc_dmub_srv' is null. The fix is to check if
'dc_dmub_srv' is null before dereferencing it.

Thus moving the null checks for 'dc_dmub_srv' to the beginning of the
functions to ensure that 'dc_dmub_srv' is not null when it is
dereferenced.

Found by smatch & thus fixing the below:
drivers/gpu/drm/amd/amdgpu/../display/dc/dc_dmub_srv.c:133 dc_dmub_srv_cmd_list_queue_execute() warn: variable dereferenced before check 'dc_dmub_srv' (see line 128)
drivers/gpu/drm/amd/amdgpu/../display/dc/dc_dmub_srv.c:1167 dc_dmub_srv_is_hw_pwr_up() warn: variable dereferenced before check 'dc_dmub_srv' (see line 1164)

References:
http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2024-26729
https://www.cve.org/CVERecord?id=CVE-2024-26729
https://git.kernel.org/stable/c/351080ba3414c96afff0f1338b4aeb2983195b80
https://git.kernel.org/stable/c/d2b48f340d9e4a8fbeb1cdc84cd8da6ad143a907
https://bugzilla.redhat.com/show_bug.cgi?id=2273256
Comment 12 Gabriele Sonnu 2024-06-07 13:40:42 UTC 
All done, closing.