btrfs: retry verity reads for not-uptodate Merkle folios

Summary

In the Linux kernel, the following vulnerability has been resolved: btrfs: retry verity reads for not-uptodate Merkle folios btrfs_read_merkle_tree_page() can find a folio in the mapping that is not uptodate. After taking the folio lock, the current code treats that state as a read error and returns -EIO. That can make a previous transient read failure sticky. If the failed read left a not-uptodate folio in the mapping, later callers find that folio and fail instead of retrying the read. Keep the existing page-cache insertion and locking order, but retry the Merkle item read when a not-uptodate folio is found in the mapping. Also unlock the folio when read_key_bytes() fails so that a later caller can lock it and retry the read.

Timeline

1. Sep 17, 2026, 4:07 PM UTCCVE published
2. Oct 19, 2026, 9:00 AM UTCRecord last updated

Affected versions

• Linux Linux

  From 06ed09351b67eb1114ae106a87a0ee3ea9adb3db · fixed in 90e9eae1b5907fa36620ffb7f4f1a4afa9333427; From 06ed09351b67eb1114ae106a87a0ee3ea9adb3db · fixed in c1fa005cdf3b7ff14cdfd7d512830088a3fc256b; From 06ed09351b67eb1114ae106a87a0ee3ea9adb3db · fixed in 12b6d1a1715cbced2e445ca353f9c9987b8636e2; From 06ed09351b67eb1114ae106a87a0ee3ea9adb3db · fixed in 81241f734f0f662378f5ffc53882b012923e6fe5; From 06ed09351b67eb1114ae106a87a0ee3ea9adb3db · fixed in 8cc569696dac51fc62bb39b3b8f530582b916d29

• Linux Linux

  6.6

• KernelLinux

  From 6.6.0 · fixed in 6.6.157; From 6.7.0 · fixed in 6.12.110; From 6.13.0 · fixed in 6.18.52; From 6.19.0 · fixed in 7.2.6

References 5