Vulnerability Description
In the Linux kernel, the following vulnerability has been resolved: gfs2: Validate i_depth for exhash directories A fuzzer test introduced corruption that ends up with a depth of 0 in dir_e_read(), causing an undefined shift by 32 at: index = hash >> (32 - dip->i_depth); As calculated in an open-coded way in dir_make_exhash(), the minimum depth for an exhash directory is ilog2(sdp->sd_hash_ptrs) and 0 is invalid as sdp->sd_hash_ptrs is fixed as sdp->bsize / 16 at mount time. So we can avoid the undefined behaviour by checking for depth values lower than the minimum in gfs2_dinode_in(). Values greater than the maximum are already being checked for there. Also switch the calculation in dir_make_exhash() to use ilog2() to clarify how the depth is calculated. Tested with the syzkaller repro.c and xfstests '-g quick'.
CVSS Score
MEDIUM
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Linux | Linux Kernel | < 6.12.43 |
References
- https://git.kernel.org/stable/c/53a0249d68a210c16e961b83adfa82f94ee0a53dPatch
- https://git.kernel.org/stable/c/557c024ca7250bb65ae60f16c02074106c2f197bPatch
- https://git.kernel.org/stable/c/9680c58675b82348ab84d387e4fa727f7587e1a0Patch
- https://git.kernel.org/stable/c/b5f46951e62377b6e406fadc18bc3c5bdf1632a7Patch
- https://git.kernel.org/stable/c/cddea0c721106ea480371412d8de21705eb27376
FAQ
What is CVE-2025-38710?
CVE-2025-38710 is a vulnerability with a CVSS score of 5.5 (MEDIUM). In the Linux kernel, the following vulnerability has been resolved: gfs2: Validate i_depth for exhash directories A fuzzer test introduced corruption that ends up with a depth of 0 in dir_e_read(), ...
How severe is CVE-2025-38710?
CVE-2025-38710 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-2025-38710?
Check the references section above for vendor advisories and patch information. Affected products include: Linux Linux Kernel.