CVE-2026-23234

In the Linux kernel, the following vulnerability has been resolved: f2fs: fix to avoid UAF in f2fs_write_end_io() As syzbot reported an use-after-free issue in f2fs_write_end_io(). It is caused by below race condition: loop device umount - worker_thread - loop_process_work - do_req_filebacked - lo_rw_aio - lo_rw_aio_complete - blk_mq_end_request - blk_update_request - f2fs_write_end_io - dec_page_count - folio_end_writeback - kill_f2fs_super - kill_block_super - f2fs_put_super : free(sbi) : get_pages(, F2FS_WB_CP_DATA) accessed sbi which is freed In kill_f2fs_super(), we will drop all page caches of f2fs inodes before call free(sbi), it guarantee that all folios should end its writeback, so it should be safe to access sbi before last folio_end_writeback(). Let's relocate ckpt thread wakeup flow before folio_end_writeback() to resolve this issue.
Configurations

Configuration 1 (hide)

OR cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*

History

17 Mar 2026, 21:21

Type Values Removed Values Added
CWE CWE-416
CVSS v2 : unknown
v3 : unknown
v2 : unknown
v3 : 7.8
CPE cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
First Time Linux
Linux linux Kernel
Summary
  • (es) En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta: f2fs: corrección para evitar UAF en f2fs_write_end_io() Como syzbot informó un problema de uso después de liberación en f2fs_write_end_io(). Es causado por la siguiente condición de carrera: loop device umount - worker_thread - loop_process_work - do_req_filebacked - lo_rw_aio - lo_rw_aio_complete - blk_mq_end_request - blk_update_request - f2fs_write_end_io - dec_page_count - folio_end_writeback - kill_f2fs_super - kill_block_super - f2fs_put_super : free(sbi) : get_pages(, F2FS_WB_CP_DATA) accedió a sbi que está liberado En kill_f2fs_super(), descartaremos todas las cachés de página de los inodos f2fs antes de llamar a free(sbi), esto garantiza que todos los folios deberían finalizar su writeback, por lo tanto, debería ser seguro acceder a sbi antes del último folio_end_writeback(). Reubicaremos el flujo de activación del hilo ckpt antes de folio_end_writeback() para resolver este problema.
References () https://git.kernel.org/stable/c/0fb58aff0dafd6837cc91f4154f3ed6e020358fa - () https://git.kernel.org/stable/c/0fb58aff0dafd6837cc91f4154f3ed6e020358fa - Patch
References () https://git.kernel.org/stable/c/2f67ff1e15a8a4d0e4ffc6564ab20d03d7398fe9 - () https://git.kernel.org/stable/c/2f67ff1e15a8a4d0e4ffc6564ab20d03d7398fe9 - Patch
References () https://git.kernel.org/stable/c/505e1c0530db6152cab3feef8e3e4da3d3e358c9 - () https://git.kernel.org/stable/c/505e1c0530db6152cab3feef8e3e4da3d3e358c9 - Patch
References () https://git.kernel.org/stable/c/995030be4ce6338c6ff814583c14166446a64008 - () https://git.kernel.org/stable/c/995030be4ce6338c6ff814583c14166446a64008 - Patch
References () https://git.kernel.org/stable/c/a42f99be8a16b32a0bb91bb6dda212a6ad61be5d - () https://git.kernel.org/stable/c/a42f99be8a16b32a0bb91bb6dda212a6ad61be5d - Patch
References () https://git.kernel.org/stable/c/acc2c97fc0005846e5cf11b5ba3189fef130c9b3 - () https://git.kernel.org/stable/c/acc2c97fc0005846e5cf11b5ba3189fef130c9b3 - Patch
References () https://git.kernel.org/stable/c/ce2739e482bce8d2c014d76c4531c877f382aa54 - () https://git.kernel.org/stable/c/ce2739e482bce8d2c014d76c4531c877f382aa54 - Patch
References () https://git.kernel.org/stable/c/cf4a9e1bc8129eb63fda5f8bdcd8d87f0bd76f42 - () https://git.kernel.org/stable/c/cf4a9e1bc8129eb63fda5f8bdcd8d87f0bd76f42 - Patch

04 Mar 2026, 15:16

Type Values Removed Values Added
New CVE

Information

Published : 2026-03-04 15:16

Updated : 2026-03-17 21:21


NVD link : CVE-2026-23234

Mitre link : CVE-2026-23234

CVE.ORG link : CVE-2026-23234


JSON object : View

Products Affected

linux

  • linux_kernel
CWE
CWE-416

Use After Free