Description
In the Linux kernel, the following vulnerability has been resolved:
fs/ntfs3: Keep write operations atomic
syzbot reported a NULL pointer dereference in __generic_file_write_iter. [1]
Before the write operation is completed, the user executes ioctl[2] to clear
the compress flag of the file, which causes the is_compressed() judgment to
return 0, further causing the program to enter the wrong process and call the
wrong ops ntfs_aops_cmpr, which triggers the null pointer dereference of
write_begin.
Use inode lock to synchronize ioctl and write to avoid this case.
[1]
Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000
Mem abort info:
ESR = 0x0000000086000006
EC = 0x21: IABT (current EL), IL = 32 bits
SET = 0, FnV = 0
EA = 0, S1PTW = 0
FSC = 0x06: level 2 translation fault
user pgtable: 4k pages, 48-bit VAs, pgdp=000000011896d000
[0000000000000000] pgd=0800000118b44403, p4d=0800000118b44403, pud=0800000117517403, pmd=0000000000000000
Internal error: Oops: 0000000086000006 [#1] PREEMPT SMP
Modules linked in:
CPU: 0 UID: 0 PID: 6427 Comm: syz-executor347 Not tainted 6.13.0-rc3-syzkaller-g573067a5a685 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
pstate: 80400005 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : 0x0
lr : generic_perform_write+0x29c/0x868 mm/filemap.c:4055
sp : ffff80009d4978a0
x29: ffff80009d4979c0 x28: dfff800000000000 x27: ffff80009d497bc8
x26: 0000000000000000 x25: ffff80009d497960 x24: ffff80008ba71c68
x23: 0000000000000000 x22: ffff0000c655dac0 x21: 0000000000001000
x20: 000000000000000c x19: 1ffff00013a92f2c x18: ffff0000e183aa1c
x17: 0004060000000014 x16: ffff800083275834 x15: 0000000000000001
x14: 0000000000000000 x13: 0000000000000001 x12: ffff0000c655dac0
x11: 0000000000ff0100 x10: 0000000000ff0100 x9 : 0000000000000000
x8 : 0000000000000000 x7 : 0000000000000000 x6 : 0000000000000000
x5 : ffff80009d497980 x4 : ffff80009d497960 x3 : 0000000000001000
x2 : 0000000000000000 x1 : ffff0000e183a928 x0 : ffff0000d60b0fc0
Call trace:
0x0 (P)
__generic_file_write_iter+0xfc/0x204 mm/filemap.c:4156
ntfs_file_write_iter+0x54c/0x630 fs/ntfs3/file.c:1267
new_sync_write fs/read_write.c:586 [inline]
vfs_write+0x920/0xcf4 fs/read_write.c:679
ksys_write+0x15c/0x26c fs/read_write.c:731
__do_sys_write fs/read_write.c:742 [inline]
__se_sys_write fs/read_write.c:739 [inline]
__arm64_sys_write+0x7c/0x90 fs/read_write.c:739
__invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49
el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132
do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151
el0_svc+0x54/0x168 arch/arm64/kernel/entry-common.c:744
el0t_64_sync_handler+0x84/0x108 arch/arm64/kernel/entry-common.c:762
[2]
ioctl$FS_IOC_SETFLAGS(r0, 0x40086602, &(0x7f00000000c0)=0x20)
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Linux | Linux | 5.15 | 6.1.191 |
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 | 6.12.27-1 | — |
| Debian 13 | linux | 6.12.27-1 | — |
| Debian 12 | linux | No fix yet | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Nvidia-BlueField 24.04 LTS | linux-bluefield | No fix yet | — |
| Ubuntu Nvidia-BlueField 22.04 LTS | linux-bluefield | No fix yet | — |
| Ubuntu 25.10 | linux-azure-fde | No fix yet | — |
| Ubuntu 25.04 | linux | 6.14.0-22.22 | USN-7594-1 |
| Ubuntu 25.04 | linux-aws +3 | 6.14.0-1007.7 | USN-7594-3, USN-7594-2, USN-7594-1 |
| Ubuntu 25.04 | linux-gcp | 6.14.0-1008.8 | USN-7594-1 |
| Ubuntu 25.04 | linux-realtime | 6.14.0-1004.4 | USN-7594-1 |
| Ubuntu 24.04 LTS | linux +28 | No fix yet | — |
| Ubuntu 24.04 LTS | linux-gcp-6.14 | 6.14.0-1011.11~24.04.1 | — |
Show 10 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 22.04 LTS | linux +59 | No fix yet | — |
| Ubuntu 20.04 LTS | linux-gke +28 | No fix yet | — |
| Ubuntu 18.04 LTS | linux-gcp +14 | No fix yet | — |
| Ubuntu 16.04 LTS | linux-hwe-edge | No fix yet | — |
| Ubuntu Pro Realtime 24.04 LTS | linux-realtime +1 | No fix yet | — |
| Ubuntu Pro Realtime 24.04 LTS | linux-realtime-6.14 | 6.14.0-1010.10~24.04.1 | — |
| Ubuntu Pro Realtime 22.04 LTS | linux-realtime +2 | No fix yet | — |
| Ubuntu Pro FIPS-updates 24.04 LTS | linux-fips +3 | No fix yet | — |
| Ubuntu Pro FIPS-updates 22.04 LTS | linux-fips +3 | No fix yet | — |
| Ubuntu Pro FIPS-preview 22.04 LTS | linux-fips +3 | No fix yet | — |
| Ubuntu Pro 20.04 LTS | linux-aws-5.15 +10 | No fix yet | — |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2023 | bpftool +14 | 6.12.29-33.102.amzn2023 | ALAS2023-2025-994 |
| Amazon Linux 2023 | kernel-livepatch-6.12.29-33.102 | 1.0-0.amzn2023 | ALAS2023-2025-994 |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 9 | kernel-uek +34 | 6.12.0-101.33.4.3.el10uek | ELSA-2025-20530, ELSA-2025-20480 |
Advisories 7
- WID-SEC-2025-0975 Linux Kernel: Mehrere Schwachstellen ermöglichen Denial of Service BSI CERT-Bund (WID) · Nov 12, 2026
- USN-7594-2 linux-azure vulnerabilities Ubuntu Security Notices (USN) · Feb 4, 2026
- USN-7594-1 linux, linux-gcp, linux-raspi, linux-realtime vulnerabilities Ubuntu Security Notices (USN) · Feb 4, 2026
- USN-7594-3 linux-aws, linux-oracle vulnerabilities Ubuntu Security Notices (USN) · Feb 4, 2026
- ALAS2023-2025-994 Important: kernel6.12 security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Aug 26, 2025
- ELSA-2025-20530 Important: Unbreakable Enterprise kernel security update (Oracle Linux 9) Oracle Linux Security Advisories (ELSA) · Aug 18, 2025
- ELSA-2025-20480 Important: Unbreakable Enterprise kernel security update (Oracle Linux 9) Oracle Linux Security Advisories (ELSA) · Jul 17, 2025
References
- https://git.kernel.org/stable/c/ad4429a5cd6b9175532d62e97262d16e60c3b166
- https://git.kernel.org/stable/c/7af81befc042853949982439f847e25fedef6598
- https://git.kernel.org/stable/c/8db49e89a7f8b48ee59fa9ad32b6ed0879747df8
- https://git.kernel.org/stable/c/464139e18f619aa14fb921a61721862f43421c54
- https://git.kernel.org/stable/c/285cec318bf5a7a6c8ba999b2b6ec96f9a20590f