Description
In the Linux kernel, the following vulnerability has been resolved: ocfs2: clear extent cache after moving/defragmenting extents The extent map cache can become stale when extents are moved or defragmented, causing subsequent operations to see outdated extent flags. This triggers a BUG_ON in ocfs2_refcount_cal_cow_clusters(). The problem occurs when: 1. copy_file_range() creates a reflinked extent with OCFS2_EXT_REFCOUNTED 2. ioctl(FITRIM) triggers ocfs2_move_extents() 3. __ocfs2_move_extents_range() reads and caches the extent (flags=0x2) 4. ocfs2_move_extent()/ocfs2_defrag_extent() calls __ocfs2_move_extent() which clears OCFS2_EXT_REFCOUNTED flag on disk (flags=0x0) 5. The extent map cache is not invalidated after the move 6. Later write() operations read stale cached flags (0x2) but disk has updated flags (0x0), causing a mismatch 7. BUG_ON(!(rec->e_flags & OCFS2_EXT_REFCOUNTED)) triggers Fix by clearing the extent map cache after each extent move/defrag operation in __ocfs2_move_extents_range(). This ensures subsequent operations read fresh extent data from disk.
Affected products
Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.
Linux Linux
Default version status: unaffected
53069d4e76954e2e63c1b3c501051c6fbcf7298c to < 93166bc53c0e3587058327a4121daea34b4fecd5affected53069d4e76954e2e63c1b3c501051c6fbcf7298c to < a7ee72286efba1d407c6f15a0528e43593fb7007affected53069d4e76954e2e63c1b3c501051c6fbcf7298c to < 93b1ab422f1966b71561158e1aedce4ec100f357affected53069d4e76954e2e63c1b3c501051c6fbcf7298c to < e92af7737a94a729225d2a5d180eaaa77fe0bbc1affected53069d4e76954e2e63c1b3c501051c6fbcf7298c to < aa6a21409dd6221bb268b56bb410e031c632ff9aaffected53069d4e76954e2e63c1b3c501051c6fbcf7298c to < bb69928ed578f881e68d26aaf1a8f6e7faab3b44affected53069d4e76954e2e63c1b3c501051c6fbcf7298c to < a21750df2f6169af6e039a3bb4893d6c9564e48daffected53069d4e76954e2e63c1b3c501051c6fbcf7298c to < 78a63493f8e352296dbc7cb7b3f4973105e8679eaffected
Linux Linux
Default version status: affected
3.0affected0 to < 3.0unaffected5.4.301 to ≤ 5.4.*unaffected5.10.246 to ≤ 5.10.*unaffected5.15.196 to ≤ 5.15.*unaffected6.1.158 to ≤ 6.1.*unaffected6.6.115 to ≤ 6.6.*unaffected6.12.56 to ≤ 6.12.*unaffected6.17.6 to ≤ 6.17.*unaffected6.18 to ≤ *unaffected
References
- https://git.kernel.org/stable/c/93166bc53c0e3587058327a4121daea34b4fecd5 ↗
- https://git.kernel.org/stable/c/a7ee72286efba1d407c6f15a0528e43593fb7007 ↗
- https://git.kernel.org/stable/c/93b1ab422f1966b71561158e1aedce4ec100f357 ↗
- https://git.kernel.org/stable/c/e92af7737a94a729225d2a5d180eaaa77fe0bbc1 ↗
- https://git.kernel.org/stable/c/aa6a21409dd6221bb268b56bb410e031c632ff9a ↗
- https://git.kernel.org/stable/c/bb69928ed578f881e68d26aaf1a8f6e7faab3b44 ↗
- https://git.kernel.org/stable/c/a21750df2f6169af6e039a3bb4893d6c9564e48d ↗
- https://git.kernel.org/stable/c/78a63493f8e352296dbc7cb7b3f4973105e8679e ↗