scsi: imm: Fix use-after-free bug caused by unfinished delayed work

Summary

In the Linux kernel, the following vulnerability has been resolved: scsi: imm: Fix use-after-free bug caused by unfinished delayed work The delayed work item 'imm_tq' is initialized in imm_attach() and scheduled via imm_queuecommand() for processing SCSI commands. When the IMM parallel port SCSI host adapter is detached through imm_detach(), the imm_struct device instance is deallocated. However, the delayed work might still be pending or executing when imm_detach() is called, leading to use-after-free bugs when the work function imm_interrupt() accesses the already freed imm_struct memory. The race condition can occur as follows: CPU 0(detach thread) | CPU 1 | imm_queuecommand() | imm_queuecommand_lck() imm_detach() | schedule_delayed_work() kfree(dev) //FREE | imm_interrupt() | dev = container_of(...) //USE dev-> //USE Add disable_delayed_work_sync() in imm_detach() to guarantee proper cancellation of the delayed work item before imm_struct is deallocated.

Timeline

1. Dec 18, 2025, 3:02 PM UTCCVE published
2. Oct 21, 2026, 12:38 PM UTCRecord last updated

Affected versions

• Linux Linux

  From 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 · fixed in 9a8e53154353580d53f7f86a253927e41294017e; From 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 · fixed in 31ab2aad7a7b7501e904a09bf361e44671f66092; From 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 · fixed in 48dd41fa2d6c6a0c50e714deeba06ffe7f91961b; From 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 · fixed in 9e434426cc23ad5e2aad649327b59aea00294b13; From 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 · fixed in ab58153ec64fa3fc9aea09ca09dc9322e0b54a7c

• Linux Linux

  2.6.12

• KernelLinux

  From 2.6.12 · fixed in 6.6.160; From 6.7.0 · fixed in 6.12.63; From 6.13.0 · fixed in 6.17.13; From 6.18.0 · fixed in 6.18.2

References 5