Bug 1215110 (CVE-2023-4206)

Summary: VUL-0: CVE-2023-4206: kernel-source,kernel-source-rt,kernel-source-azure: net/sched UAF
Product: [Novell Products] SUSE Security Incidents Reporter: Cathy Hu <cathy.hu>
Component: IncidentsAssignee: Kernel Bugs <kernel-bugs>
Status: RESOLVED DUPLICATE QA Contact: Security Team bot <security-team>
Severity: Major    
Priority: P3 - Medium CC: security-team
Version: unspecified   
Target Milestone: ---   
Hardware: Other   
OS: Other   
URL: https://smash.suse.de/issue/377514/
Whiteboard:
Found By: Security Response Team Services Priority:
Business Priority: Blocker: ---
Marketing QA Status: --- IT Deployment: ---

Description Cathy Hu 2023-09-07 08:23:54 UTC 
CVE-2023-4206

A use-after-free vulnerability in the Linux kernel's net/sched: cls_route component can be exploited to achieve local privilege escalation.

When route4_change() is called on an existing filter, the whole tcf_result struct is always copied into the new instance of the filter. This causes a problem when updating a filter bound to a class, as tcf_unbind_filter() is always called on the old instance in the success path, decreasing filter_cnt of the still referenced class and allowing it to be deleted, leading to a use-after-free.

We recommend upgrading past commit b80b829e9e2c1b3f7aae34855e04d8f6ecaf13c8.

https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=b80b829e9e2c1b3f7aae34855e04d8f6ecaf13c8
https://kernel.dance/b80b829e9e2c1b3f7aae34855e04d8f6ecaf13c8

References:
http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2023-4206
https://bugzilla.redhat.com/show_bug.cgi?id=2237757
https://www.cve.org/CVERecord?id=CVE-2023-4206
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=b80b829e9e2c1b3f7aae34855e04d8f6ecaf13c8
https://kernel.dance/b80b829e9e2c1b3f7aae34855e04d8f6ecaf13c8
Comment 1 Cathy Hu 2023-09-07 08:48:21 UTC 
It looks like a duplicate to: https://bugzilla.suse.com/show_bug.cgi?id=1214149

I will talk to mitre
Comment 2 Cathy Hu 2023-09-12 07:15:20 UTC 
Alphabet CNA confirmed that this is the same fix as bnc#1214149, closing as duplicate

*** This bug has been marked as a duplicate of bug 1214149 ***