CVE-2026-93140udf: Mark LVID buffer as uptodate before marking it dirty

Official description

In the Linux kernel, the following vulnerability has been resolved: udf: Mark LVID buffer as uptodate before marking it dirty When an I/O error occurs while writing the Logical Volume Integrity Descriptor (LVID) buffer to the block device, the block layer's completion handler (`end_buffer_write_sync()`) clears the `BH_Uptodate` flag on the buffer. However, the buffer still contains valid LVID data in memory. If the filesystem is subsequently remounted read-write or synced, `udf_open_lvid()` or `udf_sync_fs()` will modify the LVID buffer and call `mark_buffer_dirty()`. This triggers a spurious `WARN_ON_ONCE(!buffer_uptodate(bh))` warning in `mark_buffer_dirty()` because the buffer is not marked uptodate, even though its in-memory contents are valid and are about to be overwritten. To prevent this spurious warning, unconditionally set the `BH_Uptodate` flag before calling `mark_buffer_dirty()` in `udf_open_lvid()` and `udf_sync_fs()`. This acknowledges that the in-memory buffer is valid and matches the workaround previously applied to `udf_close_lvid()` in commit 853a0c25baf9 ("udf: Mark LVID buffer as uptodate before marking it dirty"). Extending this workaround ensures consistent behavior across all LVID updates. Buffer I/O error on dev loop0, logical block 128, lost sync page write ------------[ cut here ]------------ !buffer_uptodate(bh) WARNING: fs/buffer.c:1087 at mark_buffer_dirty+0x299/0x410 fs/buffer.c:1087 ... Call Trace: <TASK> udf_open_lvid+0x369/0x5b0 fs/udf/super.c:2078 udf_reconfigure+0x336/0x540 fs/udf/super.c:679 reconfigure_super+0x232/0x8f0 fs/super.c:1080 vfs_cmd_reconfigure fs/fsopen.c:268 [inline] vfs_fsconfig_locked+0x171/0x320 fs/fsopen.c:297 __do_sys_fsconfig fs/fsopen.c:463 [inline] __se_sys_fsconfig+0x6b9/0x810 fs/fsopen.c:350 do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94 </TASK>

Affected packages & fixed versions

Affected products (as reported)

References

• https://git.kernel.org/stable/c/e6461ef34f91ad7dbffdf912b3d661a7dd892931
• https://git.kernel.org/stable/c/359cea636f4a74a96c01a8050f155e12840c079a
• https://git.kernel.org/stable/c/a4c4e38b356ad4c1f90478124922917489137c08
• https://git.kernel.org/stable/c/8034ddf4751d9143c5ef7eebe3d4f33218fdd378
• https://git.kernel.org/stable/c/ee477e5204f764444e60699280abf5936c2a6ae6
• https://git.kernel.org/stable/c/11afe1912140f79d5af3091a54b181ef72fce1a5
• https://git.kernel.org/stable/c/c4058355d27488a3cd31c60c032335f77c4fdcfc
• https://git.kernel.org/stable/c/fb0601134c7e51728bd098abc6909315de1e5d86