Bug 2541303 (CVE-2026-97551)

Summary: CVE-2026-97551 kernel: xfs: initialise args->total for parent pointer updates
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: akhatavk, aos-team-art-private, asdas, dpaolell, jdelft, jupierce, lgarciaa, mbiarnes, ppalepu, ppostler, prdhamdh, rhel-process-autobot, sghai, sidsharm, suppawar, vlaad, watson-tool-maintainers
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
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Doc Text:
A flaw was found in the Linux kernel's XFS file system. A local user can trigger a Denial of Service (DoS) by forcing an unexpected filesystem shutdown. When updating parent pointer attributes, the kernel fails to properly initialize the block reservation counter, causing an integer underflow during storage space allocation. Under constrained storage conditions, this miscalculation leads to an unhandled allocation error that forces the filesystem to shut down.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description OSIDB Bzimport 2026-09-25 11:17:19 UTC 
In the Linux kernel, the following vulnerability has been resolved:

xfs: initialise args->total for parent pointer updates

xfs_parent_da_args_init() builds an xfs_da_args from a zeroed
xfs_parent_args (kmem_cache_zalloc), leaving args->total == 0.
xfs_da_grow_inode_int() treats that field as a running block reservation
and subtracts from it; because it is an xfs_extlen_t (uint32_t), the
first attr-fork growth wraps it to ~0U.  That defeats the free-space
check in xfs_alloc_space_available(), and when it coincides with an AG
that has exactly zero available blocks the allocation is clamped to
maxlen 0 and returns -ENOSPC, which xfs_defer_finish_noroll() escalates
to a filesystem shutdown.

Set args->total the way the log recovery path does
(xfs_attri_recover_work(), xfs_attr_item.c:706), in the add and replace
paths that can grow the fork.  Removals and lookups never grow it, so
they leave the field alone, matching that switch.
Comment 1 gkamathe 2026-09-28 23:21:32 UTC 
Upstream advisory:
https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-97551.mbox