Bug 2324891 (CVE-2024-50213)

Summary:	CVE-2024-50213 kernel: drm/tests: hdmi: Fix memory leaks in drm_display_mode_from_cea_vic()
Product:	[Other] Security Response	Reporter:	OSIDB Bzimport <bzimport>
Component:	vulnerability	Assignee:	Product Security DevOps Team <prodsec-dev>
Status:	NEW ---	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	dfreiber, drow, jburrell, vkumar
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
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Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:
Bug Depends On:	2325114
Bug Blocks:

Description OSIDB Bzimport 2024-11-09 11:03:36 UTC

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

drm/tests: hdmi: Fix memory leaks in drm_display_mode_from_cea_vic()

modprobe drm_hdmi_state_helper_test and then rmmod it, the following
memory leak occurs.

The `mode` allocated in drm_mode_duplicate() called by
drm_display_mode_from_cea_vic() is not freed, which cause the memory leak:

	unreferenced object 0xffffff80ccd18100 (size 128):
	  comm "kunit_try_catch", pid 1851, jiffies 4295059695
	  hex dump (first 32 bytes):
	    57 62 00 00 80 02 90 02 f0 02 20 03 00 00 e0 01  Wb........ .....
	    ea 01 ec 01 0d 02 00 00 0a 00 00 00 00 00 00 00  ................
	  backtrace (crc c2f1aa95):
	    [<000000000f10b11b>] kmemleak_alloc+0x34/0x40
	    [<000000001cd4cf73>] __kmalloc_cache_noprof+0x26c/0x2f4
	    [<00000000f1f3cffa>] drm_mode_duplicate+0x44/0x19c
	    [<000000008cbeef13>] drm_display_mode_from_cea_vic+0x88/0x98
	    [<0000000019daaacf>] 0xffffffedc11ae69c
	    [<000000000aad0f85>] kunit_try_run_case+0x13c/0x3ac
	    [<00000000a9210bac>] kunit_generic_run_threadfn_adapter+0x80/0xec
	    [<000000000a0b2e9e>] kthread+0x2e8/0x374
	    [<00000000bd668858>] ret_from_fork+0x10/0x20
	......

Free `mode` by using drm_kunit_display_mode_from_cea_vic()
to fix it.

Comment 1 Avinash Hanwate 2024-11-11 06:30:47 UTC

Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2024110923-CVE-2024-50213-6347@gregkh/T