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

f2fs: fix to avoid updating zero-sized extent in extent cache

As syzbot reported:

F2FS-fs (loop0): __update_extent_tree_range: extent len is zero, type: 0, extent [0, 0, 0], age [0, 0]
------------[ cut here ]------------
kernel BUG at fs/f2fs/extent_cache.c:678!
Oops: invalid opcode: 0000 [#1] SMP KASAN NOPTI
CPU: 0 UID: 0 PID: 5336 Comm: syz.0.0 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
RIP: 0010:__update_extent_tree_range+0x13bc/0x1500 fs/f2fs/extent_cache.c:678
Call Trace:
<TASK>
f2fs_update_read_extent_cache_range+0x192/0x3e0 fs/f2fs/extent_cache.c:1085
f2fs_do_zero_range fs/f2fs/file.c:1657 [inline]
f2fs_zero_range+0x10c1/0x1580 fs/f2fs/file.c:1737
f2fs_fallocate+0x583/0x990 fs/f2fs/file.c:2030
vfs_fallocate+0x669/0x7e0 fs/open.c:342
ioctl_preallocate fs/ioctl.c:289 [inline]
file_ioctl+0x611/0x780 fs/ioctl.c:-1
do_vfs_ioctl+0xb33/0x1430 fs/ioctl.c:576
__do_sys_ioctl fs/ioctl.c:595 [inline]
__se_sys_ioctl+0x82/0x170 fs/ioctl.c:583
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f07bc58eec9

In error path of f2fs_zero_range(), it may add a zero-sized extent
into extent cache, it should be avoided.

No CVSS v4.0

No CVSS v3.1

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

The EPSS score is 0.00032.

Key SSVC decision points have not yet been added.

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions
Linux Linux unaffected
Version Status Constraints
6e9619499f53b22ead972e476c0e8341c997d929 affected < 9c07bd262c13ca922adad6e7613d48505f97f548
6e9619499f53b22ead972e476c0e8341c997d929 affected < 72c58a82e6fb7b327e8701f5786c70c3edc56188
6e9619499f53b22ead972e476c0e8341c997d929 affected < e50b81c50fcbe63f50405bb40f262162ff32af88
6e9619499f53b22ead972e476c0e8341c997d929 affected < efe3371001f50a2d6f746b50bdc6f9f26b2089ec
6e9619499f53b22ead972e476c0e8341c997d929 affected < 4f244c64efe628d277b916f47071adf480eb8646
6e9619499f53b22ead972e476c0e8341c997d929 affected < bac23833220a1f8fe8dfab7e16efa20ff64d7589
6e9619499f53b22ead972e476c0e8341c997d929 affected < 7c37c79510329cd951a4dedf3f7bf7e2b18dccec
Linux Linux affected
Version Status Constraints
4.7 affected —
0 unaffected < 4.7
5.10.248 unaffected ≤ 5.10.*
5.15.198 unaffected ≤ 5.15.*
6.1.160 unaffected ≤ 6.1.*
6.6.120 unaffected ≤ 6.6.*
6.12.64 unaffected ≤ 6.12.*
6.18.3 unaffected ≤ 6.18.*
6.19 unaffected ≤ *

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References
Link Providers
https://git.kernel.org/stable/c/4f244c64efe628d277b916f47071adf480eb8646 cve-icon cve-icon
https://git.kernel.org/stable/c/72c58a82e6fb7b327e8701f5786c70c3edc56188 cve-icon cve-icon
https://git.kernel.org/stable/c/7c37c79510329cd951a4dedf3f7bf7e2b18dccec cve-icon cve-icon
https://git.kernel.org/stable/c/9c07bd262c13ca922adad6e7613d48505f97f548 cve-icon cve-icon
https://git.kernel.org/stable/c/bac23833220a1f8fe8dfab7e16efa20ff64d7589 cve-icon cve-icon
https://git.kernel.org/stable/c/e50b81c50fcbe63f50405bb40f262162ff32af88 cve-icon cve-icon
https://git.kernel.org/stable/c/efe3371001f50a2d6f746b50bdc6f9f26b2089ec cve-icon cve-icon
https://lore.kernel.org/linux-cve-announce/2026011306-CVE-2025-68796-9eee@gregkh/T cve-icon
https://nvd.nist.gov/vuln/detail/CVE-2025-68796 cve-icon
https://www.cve.org/CVERecord?id=CVE-2025-68796 cve-icon
History

Mon, 19 Jan 2026 12:45:00 +0000

Type Values Removed Values Added
References

Thu, 15 Jan 2026 12:15:00 +0000

Type Values Removed Values Added
References

Tue, 13 Jan 2026 15:45:00 +0000

Type Values Removed Values Added
Description In the Linux kernel, the following vulnerability has been resolved: f2fs: fix to avoid updating zero-sized extent in extent cache As syzbot reported: F2FS-fs (loop0): __update_extent_tree_range: extent len is zero, type: 0, extent [0, 0, 0], age [0, 0] ------------[ cut here ]------------ kernel BUG at fs/f2fs/extent_cache.c:678! Oops: invalid opcode: 0000 [#1] SMP KASAN NOPTI CPU: 0 UID: 0 PID: 5336 Comm: syz.0.0 Not tainted syzkaller #0 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 RIP: 0010:__update_extent_tree_range+0x13bc/0x1500 fs/f2fs/extent_cache.c:678 Call Trace: <TASK> f2fs_update_read_extent_cache_range+0x192/0x3e0 fs/f2fs/extent_cache.c:1085 f2fs_do_zero_range fs/f2fs/file.c:1657 [inline] f2fs_zero_range+0x10c1/0x1580 fs/f2fs/file.c:1737 f2fs_fallocate+0x583/0x990 fs/f2fs/file.c:2030 vfs_fallocate+0x669/0x7e0 fs/open.c:342 ioctl_preallocate fs/ioctl.c:289 [inline] file_ioctl+0x611/0x780 fs/ioctl.c:-1 do_vfs_ioctl+0xb33/0x1430 fs/ioctl.c:576 __do_sys_ioctl fs/ioctl.c:595 [inline] __se_sys_ioctl+0x82/0x170 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f07bc58eec9 In error path of f2fs_zero_range(), it may add a zero-sized extent into extent cache, it should be avoided.
Title f2fs: fix to avoid updating zero-sized extent in extent cache
First Time appeared Linux
Linux linux Kernel
CPEs cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Vendors & Products Linux
Linux linux Kernel
References

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cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published:

Updated: 2026-02-09T08:33:44.079Z

Reserved: 2025-12-24T10:30:51.042Z

Link: CVE-2025-68796

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Awaiting Analysis

Published: 2026-01-13T16:16:01.540

Modified: 2026-01-19T13:16:14.150

Link: CVE-2025-68796

cve-icon Redhat

Severity :

Publid Date: 2026-01-13T00:00:00Z

Links: CVE-2025-68796 - Bugzilla

cve-icon OpenCVE Enrichment

No data.

Weaknesses

No weakness.