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

f2fs: fix to do sanity check on sbi->total_valid_block_count

syzbot reported a f2fs bug as below:

------------[ cut here ]------------
kernel BUG at fs/f2fs/f2fs.h:2521!
RIP: 0010:dec_valid_block_count+0x3b2/0x3c0 fs/f2fs/f2fs.h:2521
Call Trace:
f2fs_truncate_data_blocks_range+0xc8c/0x11a0 fs/f2fs/file.c:695
truncate_dnode+0x417/0x740 fs/f2fs/node.c:973
truncate_nodes+0x3ec/0xf50 fs/f2fs/node.c:1014
f2fs_truncate_inode_blocks+0x8e3/0x1370 fs/f2fs/node.c:1197
f2fs_do_truncate_blocks+0x840/0x12b0 fs/f2fs/file.c:810
f2fs_truncate_blocks+0x10d/0x300 fs/f2fs/file.c:838
f2fs_truncate+0x417/0x720 fs/f2fs/file.c:888
f2fs_setattr+0xc4f/0x12f0 fs/f2fs/file.c:1112
notify_change+0xbca/0xe90 fs/attr.c:552
do_truncate+0x222/0x310 fs/open.c:65
handle_truncate fs/namei.c:3466 [inline]
do_open fs/namei.c:3849 [inline]
path_openat+0x2e4f/0x35d0 fs/namei.c:4004
do_filp_open+0x284/0x4e0 fs/namei.c:4031
do_sys_openat2+0x12b/0x1d0 fs/open.c:1429
do_sys_open fs/open.c:1444 [inline]
__do_sys_creat fs/open.c:1522 [inline]
__se_sys_creat fs/open.c:1516 [inline]
__x64_sys_creat+0x124/0x170 fs/open.c:1516
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/syscall_64.c:94

The reason is: in fuzzed image, sbi->total_valid_block_count is
inconsistent w/ mapped blocks indexed by inode, so, we should
not trigger panic for such case, instead, let's print log and
set fsck flag.
Fixes

Solution

No solution given by the vendor.


Workaround

No workaround given by the vendor.

History

Thu, 03 Jul 2025 12:30:00 +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

Moderate


Thu, 03 Jul 2025 09:00:00 +0000

Type Values Removed Values Added
Description In the Linux kernel, the following vulnerability has been resolved: f2fs: fix to do sanity check on sbi->total_valid_block_count syzbot reported a f2fs bug as below: ------------[ cut here ]------------ kernel BUG at fs/f2fs/f2fs.h:2521! RIP: 0010:dec_valid_block_count+0x3b2/0x3c0 fs/f2fs/f2fs.h:2521 Call Trace: f2fs_truncate_data_blocks_range+0xc8c/0x11a0 fs/f2fs/file.c:695 truncate_dnode+0x417/0x740 fs/f2fs/node.c:973 truncate_nodes+0x3ec/0xf50 fs/f2fs/node.c:1014 f2fs_truncate_inode_blocks+0x8e3/0x1370 fs/f2fs/node.c:1197 f2fs_do_truncate_blocks+0x840/0x12b0 fs/f2fs/file.c:810 f2fs_truncate_blocks+0x10d/0x300 fs/f2fs/file.c:838 f2fs_truncate+0x417/0x720 fs/f2fs/file.c:888 f2fs_setattr+0xc4f/0x12f0 fs/f2fs/file.c:1112 notify_change+0xbca/0xe90 fs/attr.c:552 do_truncate+0x222/0x310 fs/open.c:65 handle_truncate fs/namei.c:3466 [inline] do_open fs/namei.c:3849 [inline] path_openat+0x2e4f/0x35d0 fs/namei.c:4004 do_filp_open+0x284/0x4e0 fs/namei.c:4031 do_sys_openat2+0x12b/0x1d0 fs/open.c:1429 do_sys_open fs/open.c:1444 [inline] __do_sys_creat fs/open.c:1522 [inline] __se_sys_creat fs/open.c:1516 [inline] __x64_sys_creat+0x124/0x170 fs/open.c:1516 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/syscall_64.c:94 The reason is: in fuzzed image, sbi->total_valid_block_count is inconsistent w/ mapped blocks indexed by inode, so, we should not trigger panic for such case, instead, let's print log and set fsck flag.
Title f2fs: fix to do sanity check on sbi->total_valid_block_count
References

cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published:

Updated: 2025-07-28T04:13:56.526Z

Reserved: 2025-04-16T04:51:23.991Z

Link: CVE-2025-38163

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Awaiting Analysis

Published: 2025-07-03T09:15:31.727

Modified: 2025-07-03T15:13:53.147

Link: CVE-2025-38163

cve-icon Redhat

Severity : Moderate

Publid Date: 2025-07-03T00:00:00Z

Links: CVE-2025-38163 - Bugzilla

cve-icon OpenCVE Enrichment

Updated: 2025-07-06T22:16:22Z