CVE-2025-38710

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 v3 5.5 MEDIUM

5.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.8 / Impact : 3.6

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://git.kernel.org/stable/c/53a0249d68a210c16e961b83adfa82f94ee0a53d	Patch
https://git.kernel.org/stable/c/557c024ca7250bb65ae60f16c02074106c2f197b	Patch
https://git.kernel.org/stable/c/9680c58675b82348ab84d387e4fa727f7587e1a0	Patch
https://git.kernel.org/stable/c/b5f46951e62377b6e406fadc18bc3c5bdf1632a7	Patch

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::

History

No history.

Information

Published : 2025-09-04 16:15

Updated : 2025-11-25 22:07

NVD link : CVE-2025-38710

Mitre link : CVE-2025-38710

CVE.ORG link : CVE-2025-38710

JSON object : View

Products Affected

linux

linux_kernel

CWE

NVD-CWE-noinfo

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