CVE-2026-93798
HIGH
7,8
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Attack Vector: local
Attack Complexity: low
Privileges Required: low
User Interaction: none
Scope: unchanged
Confidentiality: high
Integrity: high
Availability: high
Description
AI Translation Available
In the Linux kernel, the following vulnerability has been resolved:
btrfs: fix reloc root cleanup in merge_reloc_roots()
If the root we got has zero root refs in its root item, we are resetting
the root's ->reloc_root without using barriers like we do everywhere else.
Sashiko complained about this while reviewing another patch, and it's
correct (see the Link tag below).
Also, we should not clear BTRFS_ROOT_DEAD_RELOC_TREE from the root unless
the root points to the reloc root we have.
Fix this by using clear_reloc_root(), which issues the memory barrier
after setting the root's ->reloc_root to NULL and before clearing the bit
BTRFS_ROOT_DEAD_RELOC_TREE from the root.
https://git.kernel.org/stable/c/63d6b1f04cd91c825329712aa526215ffa5d11ca
https://git.kernel.org/stable/c/ab48583aa9948205ff9a6470e23dbff74c565e24
https://git.kernel.org/stable/c/b78fe9563e2d5ae47805f1e5dc722c91fd30e1f8