Description
In the Linux kernel, the following vulnerability has been resolved:
ext4: fix string copying in parse_apply_sb_mount_options()
strscpy_pad() can't be used to copy a non-NUL-term string into a NUL-term
string of possibly bigger size. Commit 0efc5990bca5 ("string.h: Introduce
memtostr() and memtostr_pad()") provides additional information in that
regard. So if this happens, the following warning is observed:
strnlen: detected buffer overflow: 65 byte read of buffer size 64
WARNING: CPU: 0 PID: 28655 at lib/string_helpers.c:1032 __fortify_report+0x96/0xc0 lib/string_helpers.c:1032
Modules linked in:
CPU: 0 UID: 0 PID: 28655 Comm: syz-executor.3 Not tainted 6.12.54-syzkaller-00144-g5f0270f1ba00 #0
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
RIP: 0010:__fortify_report+0x96/0xc0 lib/string_helpers.c:1032
Call Trace:
<TASK>
__fortify_panic+0x1f/0x30 lib/string_helpers.c:1039
strnlen include/linux/fortify-string.h:235 [inline]
sized_strscpy include/linux/fortify-string.h:309 [inline]
parse_apply_sb_mount_options fs/ext4/super.c:2504 [inline]
__ext4_fill_super fs/ext4/super.c:5261 [inline]
ext4_fill_super+0x3c35/0xad00 fs/ext4/super.c:5706
get_tree_bdev_flags+0x387/0x620 fs/super.c:1636
vfs_get_tree+0x93/0x380 fs/super.c:1814
do_new_mount fs/namespace.c:3553 [inline]
path_mount+0x6ae/0x1f70 fs/namespace.c:3880
do_mount fs/namespace.c:3893 [inline]
__do_sys_mount fs/namespace.c:4103 [inline]
__se_sys_mount fs/namespace.c:4080 [inline]
__x64_sys_mount+0x280/0x300 fs/namespace.c:4080
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0x64/0x140 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x76/0x7e
Since userspace is expected to provide s_mount_opts field to be at most 63
characters long with the ending byte being NUL-term, use a 64-byte buffer
which matches the size of s_mount_opts, so that strscpy_pad() does its job
properly. Return with error if the user still managed to provide a
non-NUL-term string here.
Found by Linux Verification Center (linuxtesting.org) with Syzkaller.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Linux | Linux | 5.10.246 – < 5.10.248, 6.1.158 – < 6.1.160, 6.6.114 – < 6.6.120, 6.12.54 – < 6.12.64, 5.4.301 – < 5.5, 6.17.4 – < 6.18, 6.18 | 5.10.248 |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | linux | 6.18.3-1 | — |
| Debian 13 | linux | 6.12.69-1 | DSA-6126-1 |
| Debian 12 | linux | 6.1.162-1 | DSA-6127-1 |
| Debian 11 | linux | 5.10.249-1 | DLA-4475-1 |
| Debian 11 | linux-6.1 | 6.1.162-1~deb11u1 | DLA-4476-1 |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 25.10 | linux | 6.17.0-22.22 | USN-8177-1 |
| Ubuntu 25.10 | linux-aws +1 | 6.17.0-1012.12 | USN-8183-2, USN-8183-1 |
| Ubuntu 25.10 | linux-azure +1 | 6.17.0-1013.13 | USN-8245-1 |
| Ubuntu 25.10 | linux-oracle | 6.17.0-1011.11 | USN-8183-2 |
| Ubuntu 25.10 | linux-realtime | 6.17.0-1010.11 | USN-8177-1 |
| Ubuntu 25.10 | linux-riscv | 6.17.0-22.22.1 | — |
| Ubuntu 24.04 LTS | linux | 6.8.0-110.110 | USN-8179-1 |
| Ubuntu 24.04 LTS | linux-aws | 6.8.0-1052.55 | USN-8179-1 |
| Ubuntu 24.04 LTS | linux-aws-6.17 +1 | 6.17.0-1012.12~24.04.1 | USN-8183-2, USN-8183-1 |
| Ubuntu 24.04 LTS | linux-azure | 6.8.0-1054.60 | USN-8258-1 |
| Ubuntu 24.04 LTS | linux-azure-6.17 | 6.17.0-1013.13~24.04.1 | USN-8245-1 |
| Ubuntu 24.04 LTS | linux-gcp | 6.8.0-1054.57 | USN-8179-1 |
| Ubuntu 24.04 LTS | linux-gke | 6.8.0-1050.56 | USN-8179-1 |
| Ubuntu 24.04 LTS | linux-gkeop | 6.8.0-1037.40 | USN-8179-1 |
| Ubuntu 24.04 LTS | linux-hwe-6.17 | 6.17.0-22.22~24.04.1 | USN-8183-2 |
| Ubuntu 24.04 LTS | linux-ibm | 6.8.0-1051.51 | USN-8179-1 |
| Ubuntu 24.04 LTS | linux-lowlatency | 6.8.0-110.110.1 | USN-8179-1 |
| Ubuntu 24.04 LTS | linux-nvidia | 6.8.0-1051.54 | USN-8185-1 |
| Ubuntu 24.04 LTS | linux-nvidia-6.17 | 6.17.0-1018.18 | — |
| Ubuntu 24.04 LTS | linux-nvidia-lowlatency | 6.8.0-1051.54.1 | USN-8185-2 |
| Ubuntu 24.04 LTS | linux-nvidia-tegra | 6.8.0-1022.22 | USN-8265-1 |
| Ubuntu 24.04 LTS | linux-oem-6.17 | 6.17.0-1020.20 | USN-8245-1 |
| Ubuntu 24.04 LTS | linux-oracle | 6.8.0-1049.50 | USN-8203-1 |
| Ubuntu 24.04 LTS | linux-oracle-6.17 | 6.17.0-1011.11~24.04.1 | USN-8183-2 |
| Ubuntu 24.04 LTS | linux-raspi | 6.8.0-1052.56 | USN-8179-3 |
| Ubuntu 24.04 LTS | linux-riscv +10 | No fix yet | — |
| Ubuntu 24.04 LTS | linux-riscv-6.17 | 6.17.0-22.22.1~24.04.1 | — |
| Ubuntu 22.04 LTS | linux-aws-6.8 | 6.8.0-1052.55~22.04.1 | USN-8179-1 |
| Ubuntu 22.04 LTS | linux-azure-6.8 | 6.8.0-1059.65~22.04.1 | USN-8440-1 |
| Ubuntu 22.04 LTS | linux-gcp-6.8 | 6.8.0-1054.57~22.04.1 | USN-8179-4 |
| Ubuntu 22.04 LTS | linux-hwe-6.8 +1 | 6.8.0-110.110~22.04.1 | USN-8179-3 |
| Ubuntu 22.04 LTS | linux-ibm-6.8 | 6.8.0-1051.51~22.04.1 | USN-8179-3 |
| Ubuntu 22.04 LTS | linux-lowlatency-hwe-6.8 | 6.8.0-110.110.1~22.04.1 | USN-8179-1 |
| Ubuntu 22.04 LTS | linux-nvidia-6.8 | 6.8.0-1051.54~22.04.1 | USN-8185-1 |
| Ubuntu 22.04 LTS | linux-oracle-6.8 | 6.8.0-1049.50~22.04.1 | USN-8203-1 |
| Ubuntu 22.04 LTS | linux-riscv +32 | No fix yet | — |
| Ubuntu 20.04 LTS | linux-gke +28 | No fix yet | — |
| Ubuntu 18.04 LTS | linux-gcp +14 | No fix yet | — |
Show 4 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 16.04 LTS | linux-hwe-edge | No fix yet | — |
| Ubuntu Pro Realtime 24.04 LTS | linux-raspi-realtime | 6.8.0-2042.43 | USN-8204-1 |
| Ubuntu Pro Realtime 24.04 LTS | linux-realtime | 6.8.1-1047.48 | USN-8184-1 |
| Ubuntu Pro Realtime 24.04 LTS | linux-realtime-6.14 | No fix yet | — |
| Ubuntu Pro Realtime 24.04 LTS | linux-realtime-6.17 | 6.17.0-1010.11~24.04.1 | USN-8177-2 |
| Ubuntu Pro Realtime 22.04 LTS | linux-realtime-6.8 | 6.8.1-1047.48~22.04.1 | USN-8184-1 |
| Ubuntu Pro FIPS-updates 24.04 LTS | linux-aws-fips | 6.8.0-1052.55+fips1 | USN-8179-2 |
| Ubuntu Pro FIPS-updates 24.04 LTS | linux-azure-fips | 6.8.0-1053.59+fips1 | — |
| Ubuntu Pro FIPS-updates 24.04 LTS | linux-fips | 6.8.0-110.110+fips2 | USN-8179-2 |
| Ubuntu Pro FIPS-updates 24.04 LTS | linux-gcp-fips | 6.8.0-1054.57+fips1 | USN-8179-2 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP7 | kernel-64kb +6 | 6.4.0-150700.53.31.1 | SUSE-SU-2026:0447-1 |
| SLES 15 SP7 | kernel-azure +2 | 6.4.0-150700.20.27.1 | SUSE-SU-2026:0472-1 |
| SLES 15 SP7 | kernel-default-base | 6.4.0-150700.53.31.1.150700.17.21.1 | SUSE-SU-2026:0447-1 |
| SLES 12 SP5 | kernel-syms +2 | 4.12.14-122.293.1 | SUSE-SU-2026:0473-1 |
Show 8 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 16.0 | kernel-64kb +8 | 6.12.0-160000.26.1 | SUSE-SU-2026:20599-1 |
| SLES for SAP 16.0 | kernel-default-base | 6.12.0-160000.26.1.160000.2.7 | SUSE-SU-2026:20599-1 |
| SLES 16.0 | kernel-64kb +8 | 6.12.0-160000.26.1 | SUSE-SU-2026:20615-1, SUSE-SU-2026:20599-1 |
| SLES 16.0 | kernel-default-base | 6.12.0-160000.26.1.160000.2.7 | SUSE-SU-2026:20599-1 |
| SLE Micro 6.2 | kernel-default-base | 6.12.0-160000.26.1.160000.2.7 | SUSE-SU-2026:20555-1 |
| SLE Micro 6.2 | kernel-rt +5 | 6.12.0-160000.26.1 | SUSE-SU-2026:20570-1, SUSE-SU-2026:20555-1 |
| SLE Micro 6.1 | kernel-default-base | 6.4.0-39.1.21.16 | SUSE-SU-2026:20498-1 |
| SLE Micro 6.1 | kernel-rt +1 | 6.4.0-40.1 | SUSE-SU-2026:20876-1 |
| SLE Micro 6.1 | kernel-source +2 | 6.4.0-39.1 | SUSE-SU-2026:20498-1 |
| SLE Micro 6.0 | kernel-default-base | 6.4.0-39.1.21.16 | SUSE-SU-2026:20477-1 |
| SLE Micro 6.0 | kernel-rt +1 | 6.4.0-40.1 | SUSE-SU-2026:20845-1 |
| SLE Micro 6.0 | kernel-source +2 | 6.4.0-39.1 | SUSE-SU-2026:20477-1 |
| SLE Live Patching 15 SP7 | kernel-default | 6.4.0-150700.53.31.1 | SUSE-SU-2026:0447-1 |
| SLE Live Patching 15 SP7 | kernel-livepatch-SLE15-SP7-RT_Update_9 | 1-150700.1.3.2 | SUSE-SU-2026:0587-1 |
| SLE Live Patching 15 SP7 | kernel-livepatch-SLE15-SP7_Update_9 | 1-150700.15.3.1 | SUSE-SU-2026:0447-1 |
| SLE Live Patching 12 SP5 | kernel-default | 4.12.14-122.293.1 | SUSE-SU-2026:0473-1 |
| SLE Live Patching 12 SP5 | kgraft-patch-SLE12-SP5_Update_77 | 1-8.3.1 | SUSE-SU-2026:0473-1 |
| SUSE Real Time Module 15 SP7 | kernel-rt | 6.4.0-150700.7.31.2 | SUSE-SU-2026:0587-1 |
| SUSE Real Time Module 15 SP7 | kernel-syms-rt +1 | 6.4.0-150700.7.31.1 | SUSE-SU-2026:0587-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Leap 16.0 | kernel-default-base | 6.12.0-160000.26.1.160000.2.7 | openSUSE-SU-2026:20287-1 |
| openSUSE Leap 16.0 | kernel-rt +11 | 6.12.0-160000.26.1 | openSUSE-SU-2026:20287-1 |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2023 | kernel-livepatch-6.12.64-87.122 +1 | 1:1.0-0.amzn2023 | ALAS2023-2026-1494, ALAS2023-2026-1423 |
| Amazon Linux 2023 | perf +14 | 1:6.1.161-183.298.amzn2023 | ALAS2023-2026-1494 |
| Amazon Linux 2023 | perf6.12 +14 | 1:6.12.64-87.122.amzn2023 | ALAS2023-2026-1423 |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 9 | kernel-uek +34 | 6.12.0-108.64.6.3.el10uek | ELSA-2026-50112 |
Advisories 42
- WID-SEC-2026-0119 Linux Kernel: Mehrere Schwachstellen BSI CERT-Bund (WID) · Nov 12, 2026
- SSA-457936 SSA-457936: Vulnerabilities in the additional GNU/Linux subsystem of the SIMATIC S7-1500 CPU 1518(F)-4 PN/DP MFP V3.1.7 Siemens ProductCERT · Nov 10, 2026
- USN-8440-1 linux-azure-6.8 vulnerabilities Ubuntu Security Notices (USN) · Nov 7, 2026
- USN-8179-1 linux, linux-aws, linux-aws-6.8, linux-gcp, linux-gke, linux-gkeop, linux-ibm, linux-lowlatency, linux-lowlatency-hwe-6.8 vulnerabilities Ubuntu Security Notices (USN) · Nov 4, 2026
- USN-8183-2 linux-aws, linux-aws-6.17, linux-hwe-6.17, linux-oracle, linux-oracle-6.17 vulnerabilities Ubuntu Security Notices (USN) · Nov 4, 2026
- USN-8203-1 linux-oracle, linux-oracle-6.8 vulnerabilities Ubuntu Security Notices (USN) · Nov 4, 2026
- USN-8204-1 linux-raspi-realtime vulnerabilities Ubuntu Security Notices (USN) · Nov 4, 2026
- USN-8184-1 linux-realtime, linux-realtime-6.8 vulnerabilities Ubuntu Security Notices (USN) · Nov 4, 2026
- USN-8185-1 linux-nvidia, linux-nvidia-6.8 vulnerabilities Ubuntu Security Notices (USN) · Nov 4, 2026
- USN-8185-2 linux-nvidia-lowlatency vulnerabilities Ubuntu Security Notices (USN) · Nov 4, 2026
- USN-8179-3 linux-hwe-6.8, linux-ibm-6.8, linux-raspi vulnerabilities Ubuntu Security Notices (USN) · Nov 4, 2026
- USN-8265-1 linux-nvidia-tegra vulnerabilities Ubuntu Security Notices (USN) · Nov 4, 2026
- USN-8258-1 linux-azure vulnerabilities Ubuntu Security Notices (USN) · Nov 4, 2026
- USN-8179-4 linux-gcp-6.8 vulnerabilities Ubuntu Security Notices (USN) · Nov 4, 2026
- USN-8183-1 linux-gcp, linux-gcp-6.17 vulnerabilities Ubuntu Security Notices (USN) · Nov 4, 2026
- USN-8245-1 linux-azure, linux-azure-6.17, linux-oem-6.17 vulnerabilities Ubuntu Security Notices (USN) · Nov 4, 2026
- USN-8177-2 linux-realtime-6.17 vulnerabilities Ubuntu Security Notices (USN) · Nov 4, 2026
- USN-8179-2 linux-aws-fips, linux-fips, linux-gcp-fips vulnerabilities Ubuntu Security Notices (USN) · Nov 4, 2026
- USN-8177-1 linux, linux-realtime vulnerabilities Ubuntu Security Notices (USN) · Nov 4, 2026
- ICSA-26-295-11 Siemens SIMATIC S7-1500 CPU 1518(F)-4 PN/DP MFP CISA ICS & IT advisories · Oct 22, 2026
- SSA-019113 SSA-019113: Vulnerabilities in the additional GNU/Linux subsystem of the SIMATIC S7-1500 CPU 1518(F)-4 PN/DP MFP V3.1.6 Siemens ProductCERT · Oct 13, 2026
- ICSA-26-209-04 Siemens SIMATIC S7-1500 CPU 1518(F)-4 PN/DP MFP CISA ICS & IT advisories · Jul 28, 2026
- SUSE-SU-2026:20570-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Jul 9, 2026
- SUSE-SU-2026:20876-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 31, 2026
- SUSE-SU-2026:20845-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 28, 2026
- ALAS2023-2026-1494 Important: kernel security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Mar 27, 2026
- openSUSE-SU-2026:20287-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2026:20615-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2026:20599-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2026:20555-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2026:20498-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2026:20477-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2026:0587-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2026:0472-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2026:0447-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2026:0473-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- DSA-6127-1 linux - security update Debian Security (DSA / DLA) · Mar 9, 2026
- DSA-6126-1 linux - security update Debian Security (DSA / DLA) · Mar 9, 2026
- ELSA-2026-50112 Important: Unbreakable Enterprise kernel security update (Oracle Linux 9) Oracle Linux Security Advisories (ELSA) · Feb 20, 2026
- ALAS2023-2026-1423 Important: kernel6.12 security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Feb 11, 2026
- DLA-4475-1 linux - security update Debian Security (DSA / DLA) · Feb 10, 2026
- DLA-4476-1 linux-6.1 - security update Debian Security (DSA / DLA) · Feb 10, 2026
References
- https://git.kernel.org/stable/c/52ac96c4a2dd7bc47666000440b0602d9742e820
- https://git.kernel.org/stable/c/6e37143560e37869d51b7d9e0ac61fc48895f8a0
- https://git.kernel.org/stable/c/902ca2356f1e3ec5355c5808ad5d3f9d0095b0cc
- https://git.kernel.org/stable/c/db9ee13fab0267eccf6544ee35b16c9522db9aac
- https://git.kernel.org/stable/c/5bbacbbf1ca4419861dca3c6b82707c10e9c021c
- https://git.kernel.org/stable/c/ee5a977b4e771cc181f39d504426dbd31ed701cc