Bug 2324893 (CVE-2024-50214)

Summary:	CVE-2024-50214 kernel: drm/connector: hdmi: Fix memory leak 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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Regression:	---	Mount Type:	---
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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:	2325116
Bug Blocks:

Description OSIDB Bzimport 2024-11-09 11:03:42 UTC

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

drm/connector: hdmi: Fix memory leak in drm_display_mode_from_cea_vic()

modprobe drm_connector_test and then rmmod drm_connector_test,
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 0xffffff80cb0ee400 (size 128):
	  comm "kunit_try_catch", pid 1948, jiffies 4294950339
	  hex dump (first 32 bytes):
	    14 44 02 00 80 07 d8 07 04 08 98 08 00 00 38 04  .D............8.
	    3c 04 41 04 65 04 00 00 05 00 00 00 00 00 00 00  <.A.e...........
	  backtrace (crc 90e9585c):
	    [<00000000ec42e3d7>] kmemleak_alloc+0x34/0x40
	    [<00000000d0ef055a>] __kmalloc_cache_noprof+0x26c/0x2f4
	    [<00000000c2062161>] drm_mode_duplicate+0x44/0x19c
	    [<00000000f96c74aa>] drm_display_mode_from_cea_vic+0x88/0x98
	    [<00000000d8f2c8b4>] 0xffffffdc982a4868
	    [<000000005d164dbc>] kunit_try_run_case+0x13c/0x3ac
	    [<000000006fb23398>] kunit_generic_run_threadfn_adapter+0x80/0xec
	    [<000000006ea56ca0>] kthread+0x2e8/0x374
	    [<000000000676063f>] 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 06:39:42 UTC

Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2024110923-CVE-2024-50214-12f6@gregkh/T