Vulnerability 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.
CVSS Score
MEDIUM
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Linux | Linux Kernel | >= 4.10, < 5.10.227 |
References
- https://git.kernel.org/stable/c/5efccdee4a7d507a483f20f880b809cc4eaef14dPatch
- https://git.kernel.org/stable/c/8c30a9a8610c314554997f86370140746aa35661Patch
- https://git.kernel.org/stable/c/a9f331f51515bdb3ebc8d0963131af367ef468f6Patch
- https://git.kernel.org/stable/c/abfaa876b948baaea4d14f21a1963789845c8b4cPatch
- https://git.kernel.org/stable/c/dda898d7ffe85931f9cca6d702a51f33717c501ePatch
- https://git.kernel.org/stable/c/ec0dd451e236c46e4858d53e9e82bae7797a7af5Patch
- https://git.kernel.org/stable/c/f8a7c342326f6ad1dfdb30a18dd013c70f5e9669Patch
- https://lists.debian.org/debian-lts-announce/2025/01/msg00001.html
- https://lists.debian.org/debian-lts-announce/2025/03/msg00002.html
- https://cert-portal.siemens.com/productcert/html/ssa-265688.html
- https://cert-portal.siemens.com/productcert/html/ssa-355557.html
FAQ
What is CVE-2024-50015?
CVE-2024-50015 is a vulnerability with a CVSS score of 5.5 (MEDIUM). 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: ...
How severe is CVE-2024-50015?
CVE-2024-50015 has been rated MEDIUM with a CVSS base score of 5.5/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2024-50015?
Check the references section above for vendor advisories and patch information. Affected products include: Linux Linux Kernel.