f2fs: fix fsck inconsistency caused by incorrect nat_entry flag usage
- Published
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Not listed in CISA KEV
- Fix
- Fixed in 6.12.114, 6.18.30, 7.0.7
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
Summary
In the Linux kernel, the following vulnerability has been resolved: f2fs: fix fsck inconsistency caused by incorrect nat_entry flag usage f2fs_need_dentry_mark() reads nat_entry flags without mutual exclusion with the checkpoint path, which can result in an incorrect inode block marking state. The scenario is as follows: create & write & fsync 'file A' write checkpoint • f2fs_do_sync_file // inline inode • f2fs_write_inode // inode folio is dirty • f2fs_write_checkpoint • f2fs_flush_merged_writes • f2fs_sync_node_pages • f2fs_fsync_node_pages // no dirty node • f2fs_need_inode_block_update // return true • f2fs_fsync_node_pages // inode dirtied • f2fs_need_dentry_mark //return true • f2fs_flush_nat_entries • f2fs_write_checkpoint end • __write_node_folio // inode with DENT_BIT_SHIFT set SPO, "fsck --dry-run" find inode has already checkpointed but still with DENT_BIT_SHIFT set The state observed by f2fs_need_dentry_mark() can differ from the state observed in __write_node_folio() after acquiring sbi->node_write. The root cause is that the semantics of IS_CHECKPOINTED and HAS_FSYNCED_INODE are only guaranteed after the checkpoint write has fully completed. This patch moves set_dentry_mark() into __write_node_folio() and protects it with the sbi->node_write lock.
Timeline
- CVE published
- Record last updated
Affected versions
- Linux Linux
From 88bd02c9472a166b706284a34a84f1243322d782 · fixed in 270c519bca3a59b6140d176415aff16e4e06f9e3; From 88bd02c9472a166b706284a34a84f1243322d782 · fixed in bedb710b63ae1bd617e65d0a8cf6cea1200b3753; From 88bd02c9472a166b706284a34a84f1243322d782 · fixed in b28a83ea4934215b5de906c3ee4fbfbc651573e0; From 88bd02c9472a166b706284a34a84f1243322d782 · fixed in 019f9dda7f66e55eb94cd32e1d3fff5835f73fbc
- Linux Linux
3.18
- KernelLinux
From 3.18.0 · fixed in 6.12.114; From 6.13.0 · fixed in 6.18.30; From 6.19.0 · fixed in 7.0.7