Bug 1224523 (CVE-2024-35880)

Summary: VUL-0: CVE-2024-35880: kernel: io_uring/kbuf: hold io_buffer_list reference over mmap
Product: [Novell Products] SUSE Security Incidents Reporter: SMASH SMASH <smash_bz>
Component: IncidentsAssignee: Security Team bot <security-team>
Status: IN_PROGRESS --- QA Contact: Security Team bot <security-team>
Severity: Normal    
Priority: P3 - Medium CC: gabriel.bertazi, gabriele.sonnu, jlee
Version: unspecified   
Target Milestone: ---   
Hardware: Other   
OS: Other   
URL: https://smash.suse.de/issue/406569/
Whiteboard: CVSSv3.1:SUSE:CVE-2024-35880:5.5:(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 2024-05-20 13:28:29 UTC 
In the Linux kernel, the following vulnerability has been resolved:

io_uring/kbuf: hold io_buffer_list reference over mmap

If we look up the kbuf, ensure that it doesn't get unregistered until
after we're done with it. Since we're inside mmap, we cannot safely use
the io_uring lock. Rely on the fact that we can lookup the buffer list
under RCU now and grab a reference to it, preventing it from being
unregistered until we're done with it. The lookup returns the
io_buffer_list directly with it referenced.

References:
http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2024-35880
https://www.cve.org/CVERecord?id=CVE-2024-35880
https://git.kernel.org/stable/c/561e4f9451d65fc2f7eef564e0064373e3019793
https://git.kernel.org/stable/c/5fd8e2359498043e0b5329a05f02d10a9eb91eb9
https://git.kernel.org/stable/c/65938e81df2197203bda4b9a0c477e7987218d66
https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2024/CVE-2024-35880.mbox