Bug 2323934 (CVE-2024-50116)

Summary: CVE-2024-50116 kernel: nilfs2: fix kernel bug due to missing clearing of buffer delay flag
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
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Priority: medium    
Version: unspecifiedCC: dfreiber, drow, jburrell, vkumar
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Hardware: All   
OS: Linux   
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Bug Depends On: 2324023    
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Description OSIDB Bzimport 2024-11-05 18:03:08 UTC 
In the Linux kernel, the following vulnerability has been resolved:

nilfs2: fix kernel bug due to missing clearing of buffer delay flag

Syzbot reported that after nilfs2 reads a corrupted file system image
and degrades to read-only, the BUG_ON check for the buffer delay flag
in submit_bh_wbc() may fail, causing a kernel bug.

This is because the buffer delay flag is not cleared when clearing the
buffer state flags to discard a page/folio or a buffer head. So, fix
this.

This became necessary when the use of nilfs2's own page clear routine
was expanded.  This state inconsistency does not occur if the buffer
is written normally by log writing.
Comment 1 Robb Gatica 2024-11-05 21:07:02 UTC 
Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2024110555-CVE-2024-50116-64fb@gregkh/T