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

ext4: fix BUG in ext4_mb_new_inode_pa() due to overflow

When we calculate the end position of ext4_free_extent, this position may
be exactly where ext4_lblk_t (i.e. uint) overflows. For example, if
ac_g_ex.fe_logical is 4294965248 and ac_orig_goal_len is 2048, then the
computed end is 0x100000000, which is 0. If ac->ac_o_ex.fe_logical is not
the first case of adjusting the best extent, that is, new_bex_end > 0, the
following BUG_ON will be triggered:

=========================================================
kernel BUG at fs/ext4/mballoc.c:5116!
invalid opcode: 0000 [#1] PREEMPT SMP PTI
CPU: 3 PID: 673 Comm: xfs_io Tainted: G E 6.5.0-rc1+ #279
RIP: 0010:ext4_mb_new_inode_pa+0xc5/0x430
Call Trace:
<TASK>
ext4_mb_use_best_found+0x203/0x2f0
ext4_mb_try_best_found+0x163/0x240
ext4_mb_regular_allocator+0x158/0x1550
ext4_mb_new_blocks+0x86a/0xe10
ext4_ext_map_blocks+0xb0c/0x13a0
ext4_map_blocks+0x2cd/0x8f0
ext4_iomap_begin+0x27b/0x400
iomap_iter+0x222/0x3d0
__iomap_dio_rw+0x243/0xcb0
iomap_dio_rw+0x16/0x80
=========================================================

A simple reproducer demonstrating the problem:

mkfs.ext4 -F /dev/sda -b 4096 100M
mount /dev/sda /tmp/test
fallocate -l1M /tmp/test/tmp
fallocate -l10M /tmp/test/file
fallocate -i -o 1M -l16777203M /tmp/test/file
fsstress -d /tmp/test -l 0 -n 100000 -p 8 &
sleep 10 && killall -9 fsstress
rm -f /tmp/test/tmp
xfs_io -c "open -ad /tmp/test/file" -c "pwrite -S 0xff 0 8192"

We simply refactor the logic for adjusting the best extent by adding
a temporary ext4_free_extent ex and use extent_logical_end() to avoid
overflow, which also simplifies the code.

Metrics

No CVSS v4.0

Attack Vector Local

Attack Complexity Low

Privileges Required Low

Scope Unchanged

Confidentiality Impact None

Integrity Impact None

Availability Impact High

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

The EPSS score is 0.00024.

Key SSVC decision points have not yet been added.

Affected Vendors & Products

Vendors Products
Linux Subscribe
Linux Kernel Subscribe

No data.

No data.

No data.

Advisories

No advisories yet.

Fixes

Solution

No solution given by the vendor.

Workaround

No workaround given by the vendor.

References
Link Providers
https://git.kernel.org/stable/c/58fe961c606c446f5612f6897827b1cac42c2e89 cve-icon cve-icon
https://git.kernel.org/stable/c/83ecffd40c65844a73c2e93d7c841455786605ac cve-icon cve-icon
https://git.kernel.org/stable/c/b7e9ec38b6a0beb5a49cd1e76be0a9a07c218e90 cve-icon cve-icon
https://git.kernel.org/stable/c/bc056e7163ac7db945366de219745cf94f32a3e6 cve-icon cve-icon
https://git.kernel.org/stable/c/f2c3a3aa6f11ad9878dbc3a067b0633e07b586c1 cve-icon cve-icon
https://git.kernel.org/stable/c/fcefddf3a151b2c416b20120c06bb1ba9ad676fb cve-icon cve-icon
https://lore.kernel.org/linux-cve-announce/2025122431-CVE-2023-54069-1a17@gregkh/T cve-icon
https://nvd.nist.gov/vuln/detail/CVE-2023-54069 cve-icon
https://www.cve.org/CVERecord?id=CVE-2023-54069 cve-icon
History

Thu, 25 Dec 2025 12:15:00 +0000

Type Values Removed Values Added
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

Wed, 24 Dec 2025 12:45:00 +0000

Type Values Removed Values Added
Description In the Linux kernel, the following vulnerability has been resolved: ext4: fix BUG in ext4_mb_new_inode_pa() due to overflow When we calculate the end position of ext4_free_extent, this position may be exactly where ext4_lblk_t (i.e. uint) overflows. For example, if ac_g_ex.fe_logical is 4294965248 and ac_orig_goal_len is 2048, then the computed end is 0x100000000, which is 0. If ac->ac_o_ex.fe_logical is not the first case of adjusting the best extent, that is, new_bex_end > 0, the following BUG_ON will be triggered: ========================================================= kernel BUG at fs/ext4/mballoc.c:5116! invalid opcode: 0000 [#1] PREEMPT SMP PTI CPU: 3 PID: 673 Comm: xfs_io Tainted: G E 6.5.0-rc1+ #279 RIP: 0010:ext4_mb_new_inode_pa+0xc5/0x430 Call Trace: <TASK> ext4_mb_use_best_found+0x203/0x2f0 ext4_mb_try_best_found+0x163/0x240 ext4_mb_regular_allocator+0x158/0x1550 ext4_mb_new_blocks+0x86a/0xe10 ext4_ext_map_blocks+0xb0c/0x13a0 ext4_map_blocks+0x2cd/0x8f0 ext4_iomap_begin+0x27b/0x400 iomap_iter+0x222/0x3d0 __iomap_dio_rw+0x243/0xcb0 iomap_dio_rw+0x16/0x80 ========================================================= A simple reproducer demonstrating the problem: mkfs.ext4 -F /dev/sda -b 4096 100M mount /dev/sda /tmp/test fallocate -l1M /tmp/test/tmp fallocate -l10M /tmp/test/file fallocate -i -o 1M -l16777203M /tmp/test/file fsstress -d /tmp/test -l 0 -n 100000 -p 8 & sleep 10 && killall -9 fsstress rm -f /tmp/test/tmp xfs_io -c "open -ad /tmp/test/file" -c "pwrite -S 0xff 0 8192" We simply refactor the logic for adjusting the best extent by adding a temporary ext4_free_extent ex and use extent_logical_end() to avoid overflow, which also simplifies the code.
Title ext4: fix BUG in ext4_mb_new_inode_pa() due to overflow
First Time appeared Linux
Linux linux Kernel
CPEs cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Vendors & Products Linux
Linux linux Kernel
References

Projects

Sign in to view the affected projects.

cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published:

Updated: 2025-12-24T12:23:13.504Z

Reserved: 2025-12-24T12:21:05.093Z

Link: CVE-2023-54069

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2025-12-24T13:16:08.747

Modified: 2025-12-24T13:16:08.747

Link: CVE-2023-54069

cve-icon Redhat

Severity : Low

Publid Date: 2025-12-24T00:00:00Z

Links: CVE-2023-54069 - Bugzilla

cve-icon OpenCVE Enrichment

No data.

Weaknesses

No weakness.