CVE-2026-64600 (GCVE-0-2026-64600)
Vulnerability from cvelistv5
Published
2026-07-23 05:46
Modified
2026-08-17 04:58
Severity ?
7.8 (High) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Summary
In the Linux kernel, the following vulnerability has been resolved: xfs: resample the data fork mapping after cycling ILOCK xfs_reflink_fill_{cow_hole,delalloc} are both presented with an inode, a data fork mapping, and a cow fork mapping. Unfortunately, these two helpers cycle the ILOCK to grab a transaction, which means that the mappings are stale as soon as we reacquire the ILOCK. Currently we refresh the cow fork mapping by re-calling xfs_find_trim_cow_extent, but we don't refresh the data fork mapping beforehand, which means that the xfs_bmap_trim_cow in that function queries the refcount btree about the wrong physical blocks and returns an inaccurate value in *shared. If *shared is now false, the directio write proceeds with a stale data fork mapping. Fix this by querying the data fork mapping if the sequence counter changes across the ILOCK cycle.
References
Impacted products
Vendor Product Version
Linux Linux Version: 3c68d44a2b49a0ac9165faa9c191e1e618c8a8d5
Version: 3c68d44a2b49a0ac9165faa9c191e1e618c8a8d5
Version: 3c68d44a2b49a0ac9165faa9c191e1e618c8a8d5
Version: 3c68d44a2b49a0ac9165faa9c191e1e618c8a8d5
Version: 3c68d44a2b49a0ac9165faa9c191e1e618c8a8d5
Version: 3c68d44a2b49a0ac9165faa9c191e1e618c8a8d5
Version: 3c68d44a2b49a0ac9165faa9c191e1e618c8a8d5
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