Bug 1224848 (CVE-2021-47232)

Summary: VUL-0: CVE-2021-47232: kernel: can: j1939: fix Use-after-Free, hold skb ref while in use
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: gabriele.sonnu, mhocko
Version: unspecified   
Target Milestone: ---   
Hardware: Other   
OS: Other   
URL: https://smash.suse.de/issue/406859/
Whiteboard: CVSSv3.1:SUSE:CVE-2021-47232:5.5:(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 2024-05-22 08:09:59 UTC 
In the Linux kernel, the following vulnerability has been resolved:

can: j1939: fix Use-after-Free, hold skb ref while in use

This patch fixes a Use-after-Free found by the syzbot.

The problem is that a skb is taken from the per-session skb queue,
without incrementing the ref count. This leads to a Use-after-Free if
the skb is taken concurrently from the session queue due to a CTS.

References:
http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2021-47232
https://www.cve.org/CVERecord?id=CVE-2021-47232
https://git.kernel.org/stable/c/1071065eeb33d32b7d98c2ce7591881ae7381705
https://git.kernel.org/stable/c/2030043e616cab40f510299f09b636285e0a3678
https://git.kernel.org/stable/c/22cba878abf646cd3a02ee7c8c2cef7afe66a256
https://git.kernel.org/stable/c/509ab6bfdd0c76daebbad0f0af07da712116de22
https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2021/CVE-2021-47232.mbox
Comment 2 Michal Hocko 2024-05-23 16:03:42 UTC 
nothing to be done
Comment 3 Gabriele Sonnu 2024-06-10 12:07:11 UTC 
All done, closing.