Description
In the Linux kernel, the following vulnerability has been resolved: ext4: dax: fix overflowing extents beyond inode size when partially writing The dax_iomap_rw() does two things in each iteration: map written blocks and copy user data to blocks. If the process is killed by user(See signal handling in dax_iomap_iter()), the copied data will be returned and added on inode size, which means that the length of written extents may exceed the inode size, then fsck will fail. An example is given as: dd if=/dev/urandom of=file bs=4M count=1 dax_iomap_rw iomap_iter // round 1 ext4_iomap_begin ext4_iomap_alloc // allocate 0~2M extents(written flag) dax_iomap_iter // copy 2M data iomap_iter // round 2 iomap_iter_advance iter->pos += iter->processed // iter->pos = 2M ext4_iomap_begin ext4_iomap_alloc // allocate 2~4M extents(written flag) dax_iomap_iter fatal_signal_pending done = iter->pos - iocb->ki_pos // done = 2M ext4_handle_inode_extension ext4_update_inode_size // inode size = 2M fsck reports: Inode 13, i_size is 2097152, should be 4194304. Fix? Fix the problem by truncating extents if the written length is smaller than expected.
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
776722e85d3b0936253ecc3d14db4fba37f191ba to < f8a7c342326f6ad1dfdb30a18dd013c70f5e9669affected776722e85d3b0936253ecc3d14db4fba37f191ba to < 8c30a9a8610c314554997f86370140746aa35661affected776722e85d3b0936253ecc3d14db4fba37f191ba to < abfaa876b948baaea4d14f21a1963789845c8b4caffected776722e85d3b0936253ecc3d14db4fba37f191ba to < 5efccdee4a7d507a483f20f880b809cc4eaef14daffected776722e85d3b0936253ecc3d14db4fba37f191ba to < a9f331f51515bdb3ebc8d0963131af367ef468f6affected776722e85d3b0936253ecc3d14db4fba37f191ba to < ec0dd451e236c46e4858d53e9e82bae7797a7af5affected776722e85d3b0936253ecc3d14db4fba37f191ba to < dda898d7ffe85931f9cca6d702a51f33717c501eaffected
Linux Linux
Default version status: affected
4.10affected0 to < 4.10unaffected5.10.227 to ≤ 5.10.*unaffected5.15.168 to ≤ 5.15.*unaffected6.1.113 to ≤ 6.1.*unaffected6.6.55 to ≤ 6.6.*unaffected6.10.14 to ≤ 6.10.*unaffected6.11.3 to ≤ 6.11.*unaffected6.12 to ≤ *unaffected
References
- https://git.kernel.org/stable/c/f8a7c342326f6ad1dfdb30a18dd013c70f5e9669 ↗
- https://git.kernel.org/stable/c/8c30a9a8610c314554997f86370140746aa35661 ↗
- https://git.kernel.org/stable/c/abfaa876b948baaea4d14f21a1963789845c8b4c ↗
- https://git.kernel.org/stable/c/5efccdee4a7d507a483f20f880b809cc4eaef14d ↗
- https://git.kernel.org/stable/c/a9f331f51515bdb3ebc8d0963131af367ef468f6 ↗
- https://git.kernel.org/stable/c/ec0dd451e236c46e4858d53e9e82bae7797a7af5 ↗
- https://git.kernel.org/stable/c/dda898d7ffe85931f9cca6d702a51f33717c501e ↗
- https://lists.debian.org/debian-lts-announce/2025/03/msg00002.html ↗
- https://lists.debian.org/debian-lts-announce/2025/01/msg00001.html ↗
- https://cert-portal.siemens.com/productcert/html/ssa-265688.html ↗
- https://cert-portal.siemens.com/productcert/html/ssa-355557.html ↗