Bug 1210990 (CVE-2023-2236)

Summary:	VUL-0: CVE-2023-2236: kernel: use-after-free in io_uring subsystem
Product:	[Novell Products] SUSE Security Incidents	Reporter:	Alexander Bergmann <abergmann>
Component:	Incidents	Assignee:	Security Team bot <security-team>
Status:	RESOLVED DUPLICATE	QA Contact:	Security Team bot <security-team>
Severity:	Major
Priority:	P3 - Medium	CC:	mhocko, security-team
Version:	unspecified
Target Milestone:	---
Hardware:	Other
OS:	Other
URL:	https://smash.suse.de/issue/364833/
Whiteboard:
Found By:	Security Response Team	Services Priority:
Business Priority:		Blocker:	---
Marketing QA Status:	---	IT Deployment:	---
Bug Depends on:
Bug Blocks:	1210991

Description Alexander Bergmann 2023-05-02 06:53:26 UTC

CVE-2023-2236

A use-after-free vulnerability in the Linux Kernel io_uring subsystem can be
exploited to achieve local privilege escalation.

Both io_install_fixed_file and its callers call fput in a file in case of an
error, causing a reference underflow which leads to a use-after-free
vulnerability.

We recommend upgrading past commit 9d94c04c0db024922e886c9fd429659f22f48ea4.



References:
http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2023-2236
https://www.cve.org/CVERecord?id=CVE-2023-2236
http://www.cvedetails.com/cve/CVE-2023-2236/
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=9d94c04c0db024922e886c9fd429659f22f48ea4
https://kernel.dance/9d94c04c0db024922e886c9fd429659f22f48ea4

Comment 1 Michal Hocko 2023-05-02 09:44:53 UTC

This is a fixup for 
339f24b336d ("io_uring: allow allocated fixed files for openat/openat2")
61c1b44a21d7 ("io_uring: fix deadlock on iowq file slot alloc")

both 5.19. 15-sp5 has them backported but it also has this follow up fix. I will just update the reference. 15-sp4 and older do not have none.

Back to the security team.

Comment 2 Michal Hocko 2023-05-02 09:48:42 UTC

Hmm, looking at the patch in 15-sp5 this is a duplicate of bug 1207521 CVE-2023-0469. Should the CVE be dismissed or should I add another reference?

Comment 3 Michal Hocko 2023-05-02 09:49:18 UTC

Duplicate of bug 1207521

*** This bug has been marked as a duplicate of bug 1207521 ***