CVE-2026-46175 f2fs: fix fsck inconsistency caused by FGGC of node block
A flaw in the Linux kernel's f2fs filesystem causes fsck to misinterpret migrated node blocks, potentially leading to filesystem inconsistency and data corruption.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-46175?
CVE-2026-46175 is a high-severity vulnerability in Linux kernel, published on 28 May 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
f2fs: fix fsck inconsistency caused by FGGC of node block
During FGGC node block migration, fsck may incorrectly treat the migrated node block as fsync-written data.
The reproduction scenario: root@vm:/mnt/f2fs# seq 1 2048 | xargs -n 1 ./test_sync // write inline inode and sync root@vm:/mnt/f2fs# rm -f 1 root@vm:/mnt/f2fs# sync root@vm:/mnt/f2fs# f2fs_io gc_range // move data block in sync mode and not write CP SPO, "fsck --dry-run" find inode has already checkpointed but still with DENT_BIT_SHIFT set
The root cause is that GC does not clear the dentry mark and fsync mark during node block migration, leading fsck to misinterpret them as user-issued fsync writes.
In BGGC mode, node block migration is handled by f2fs_sync_node_pages(), which guarantees the dentry and fsync marks are cleared before writing.
This patch move the set/clear of the fsync|dentry marks into __write_node_folio to make the logic clearer, and ensures the fsync|dentry mark is cleared in FGGC.
Which versions are affected by CVE-2026-46175?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2026-46175?
Apply the vendor's patch.
Is CVE-2026-46175 being exploited?
There is no known exploitation of CVE-2026-46175 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as AZL-88860, BELL-CVE-2026-46175, DEBIAN-CVE-2026-46175, GHSA-vwpg-8m6q-566g, ROOT-OS-DEBIAN-11-CVE-2026-46175, ROOT-OS-DEBIAN-12-CVE-2026-46175 and 4 more.