Vulnerability Database

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Total vulnerabilities in the database

CVE-2025-38710 — linux / linux_kernel

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'.

  • Published: Sep 4, 2025
  • Updated: Nov 26, 2025
  • CVE: CVE-2025-38710
  • Severity: Medium
  • Exploit:
  • CISA KEV:

CVSS v3:

  • Severity: High
  • Score: 7.8
  • AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

No CWE or OWASP classifications available.

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