In the Linux kernel, the following vulnerability has been resolved:

smb/client: validate new EOF for zero range

When FALLOC_FL_ZERO_RANGE is used without FALLOC_FL_KEEP_SIZE,
smb3_zero_range() may extend EOF without checking RLIMIT_FSIZE, allowing
the file to grow beyond the caller's file-size limit.

Fix this by calling inode_newsize_ok() before sending the zero-range
request when the operation would extend EOF.

Reproducer, using a file on a CIFS mount:

bash -c '
FILE=/mnt/cifs/repro

trap "" SIGXFSZ
ulimit -f 3072

truncate -s 2M "$FILE"
fallocate --zero-range -o 0 -l 4M "$FILE"
echo "fallocate rc=$?"
stat -c "file size=%s" "$FILE"
'

Before this change, the operation succeeds despite the 3 MiB limit:

fallocate rc=0
file size=4194304

After this change, fallocate fails and leaves the file at 2 MiB.
Advisories
Source ID Title
Debian DLA Debian DLA DLA-4817-1 linux-6.12 security update
Debian DSA Debian DSA DSA-6528-1 linux security update
Fixes

Solution

No solution given by the vendor.


Workaround

No workaround given by the vendor.

History

Thu, 22 Oct 2026 16:15:00 +0000

Type Values Removed Values Added
CPEs cpe:2.3:o:linux:linux_kernel:7.3:rc1:*:*:*:*:*:*

Wed, 21 Oct 2026 13:15:00 +0000


Tue, 29 Sep 2026 21:15:00 +0000

Type Values Removed Values Added
Weaknesses CWE-367

Tue, 29 Sep 2026 13:15:00 +0000

Type Values Removed Values Added
Weaknesses CWE-770
References
Metrics threat_severity

None

cvssV3_1

{'score': 5.5, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'}

threat_severity

Low


Fri, 25 Sep 2026 12:00:00 +0000

Type Values Removed Values Added
Weaknesses CWE-367

Fri, 25 Sep 2026 10:45:00 +0000

Type Values Removed Values Added
Description In the Linux kernel, the following vulnerability has been resolved: smb/client: validate new EOF for zero range When FALLOC_FL_ZERO_RANGE is used without FALLOC_FL_KEEP_SIZE, smb3_zero_range() may extend EOF without checking RLIMIT_FSIZE, allowing the file to grow beyond the caller's file-size limit. Fix this by calling inode_newsize_ok() before sending the zero-range request when the operation would extend EOF. Reproducer, using a file on a CIFS mount: bash -c ' FILE=/mnt/cifs/repro trap "" SIGXFSZ ulimit -f 3072 truncate -s 2M "$FILE" fallocate --zero-range -o 0 -l 4M "$FILE" echo "fallocate rc=$?" stat -c "file size=%s" "$FILE" ' Before this change, the operation succeeds despite the 3 MiB limit: fallocate rc=0 file size=4194304 After this change, fallocate fails and leaves the file at 2 MiB.
Title smb/client: validate new EOF for zero range
First Time appeared Linux
Linux linux Kernel
CPEs cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Vendors & Products Linux
Linux linux Kernel
References

Projects

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cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published:

Updated: 2026-10-21T12:54:37.445Z

Reserved: 2026-09-25T10:25:14.318Z

Link: CVE-2026-98126

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Analyzed

Published: 2026-09-25T11:17:43.940

Modified: 2026-10-22T16:02:09.817

Link: CVE-2026-98126

cve-icon Redhat

Severity : Low

Publid Date: 2026-09-25T00:00:00Z

Links: CVE-2026-98126 - Bugzilla

cve-icon OpenCVE Enrichment

Updated: 2026-09-30T11:15:16Z

Weaknesses