Bug 2511396 (CVE-2026-71221)

Summary: CVE-2026-71221 gfs2-utils: gfs2-utils: stack out-of-bounds write via unchecked height in savemeta
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: rhel-process-autobot, security-response-team, watson-tool-maintainers
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
Whiteboard:
Fixed In Version: Doc Type: ---
Doc Text:
A stack out-of-bounds write vulnerability was found in gfs2-utils. In savemeta, the height value from on-disk inode metadata is used as a loop bound without bounds checking, causing a stack buffer overflow that may lead to arbitrary code execution when processing crafted GFS2 filesystem images.
 Story Points: ---
Clone Of: Environment:
Last Closed: Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:
Bug Depends On: 2527993    
Bug Blocks:    

Description OSIDB Bzimport 2026-08-05 08:39:11 UTC 
A flaw was found in gfs2-utils. In the savemeta function in savemeta.c, the height value from on-disk inode metadata controls a loop over a fixed-size stack array (10 elements) without bounds validation. An attacker can craft a GFS2 filesystem image with a height value exceeding 10 to write past the end of the array, corrupting adjacent stack memory. This is the same vulnerability class as the di_height OOB write in gfs2_edit (extended.c) but in a different code path. The stack buffer overflow may allow arbitrary code execution when savemeta processes the crafted image. The Linux kernel GFS2 driver validates i_height against sd_max_height in gfs2_dinode_in(), but the userspace gfs2-utils performs no equivalent validation.