Bug 2230042 (CVE-2023-38409)

Summary:	CVE-2023-38409 kernel: fbcon: out-of-sync arrays in fbcon_mode_deleted due to wrong con2fb_map assignment
Product:	[Other] Security Response	Reporter:	Rohit Keshri <rkeshri>
Component:	vulnerability	Assignee:	Nobody <nobody>
Status:	NEW ---	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	acaringi, allarkin, bhu, chwhite, dbohanno, ddepaula, debarbos, dfreiber, dvlasenk, ezulian, hkrzesin, jarod, jburrell, jdenham, jfaracco, jferlan, jforbes, jlelli, joe.lawrence, jshortt, jstancek, jwyatt, kcarcia, kernel-mgr, ldoskova, lgoncalv, lleshchi, lzampier, nmurray, ptalbert, qzhao, rogbas, rrobaina, rvrbovsk, rysulliv, scweaver, swood, tglozar, tyberry, vkumar, walters, wcosta, williams, wmealing, ycote, ymankad
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
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oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
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Bug Blocks:	2224231

Description Rohit Keshri 2023-08-08 14:29:08 UTC

An issue was discovered in set_con2fb_map in drivers/video/fbdev/core/fbcon.c in the Linux kernel before 6.2.12. Because an assignment occurs only for the first vc, the fbcon_registered_fb and fbcon_display arrays can be desynchronized in fbcon_mode_deleted (the con2fb_map points at the old fb_info).

https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit?id=fffb0b52d5258554c645c966c6cbef7de50b851d
https://cdn.kernel.org/pub/linux/kernel/v6.x/ChangeLog-6.2.12