CVE-2026-43187
In the Linux kernel, the following vulnerability has been resolved: xfs: delete attr leaf freemap entries when empty Back in commit 2a2b5932db6758 ("xfs: fix attr leaf header freemap.size underflow"), Brian Foster observed that it's possible for a small freemap at the end of the end of the xattr entries array to experience a size underflow when subtracting the space consumed by an expansion of the entries array. There are only three freemap entries, which means that it is not a complete index of all free space in the leaf block. This code can leave behind a zero-length freemap entry with a nonzero base. Subsequent setxattr operations can increase the base up to the point that it overlaps with another freemap entry. This isn't in and of itself a problem because the code in _leaf_add that finds free space ignores any freemap entry with zero size. However, there's another bug in the freemap update code in _leaf_add, which is that it fails to update a freemap entry that begins midway through the xattr entry that was just appended to the array. That can result in the freemap containing two entries with the same base but different sizes (0 for the "pushed-up" entry, nonzero for the entry
Słabość
In the Linux kernel, the following vulnerability has been resolved: xfs: delete attr leaf freemap entries when empty Back in commit 2a2b5932db6758 ("xfs: fix attr leaf header freemap.size underflow"), Brian Foster observed that it's possible for a small freemap at the end of the end of the xattr entries array to experience a size underflow when subtracting the space consumed by an expansion of the entries array. There are only three freemap entries, which means that it is not a complete index of all free space in the leaf block. This code can leave behind a zero-length freemap entry with a nonzero base. Subsequent setxattr operations can increase the base up to the point that it overlaps with another freemap entry. This isn't in and of itself a problem because the code in _leaf_add that finds free space ignores any freemap entry with zero size. However, there's another bug in the freemap update code in _leaf_add, which is that it fails to update a freemap entry that begins midway through the xattr entry that was just appended to the array. That can result in the freemap containing two entries with the same base but different sizes (0 for the "pushed-up" entry, nonzero for the entry
Produkty, których dotyczy
- linux linux_kernel
Źródła
- https://git.kernel.org/stable/c/479b05fc3ee272090f671b06a41f3da8aa78eece
- https://git.kernel.org/stable/c/6f13c1d2a6271c2e73226864a0e83de2770b6f34
- https://git.kernel.org/stable/c/a631899025d47ea1aa6464d76db5b4d3b6d196fd
- https://git.kernel.org/stable/c/aa9083d97e2157da3c6fb45ddb1a97af7f188f7f
- https://git.kernel.org/stable/c/e1b8c6452ee99a30e188a88f3f3f804fb1c6004a
- https://git.kernel.org/stable/c/f31a8334e1c54b126fcecf98645a49b6bc5ad399
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