diff options
| author | Duoming Zhou <duoming@zju.edu.cn> | 2025-10-28 18:01:49 +0800 |
|---|---|---|
| committer | Martin K. Petersen <martin.petersen@oracle.com> | 2025-11-29 15:42:17 -0500 |
| commit | ab58153ec64fa3fc9aea09ca09dc9322e0b54a7c (patch) | |
| tree | e824ef2a3527bd7b45a70acb327c6380dd763bb0 | |
| parent | 971bb08704e227a7815fef31713f25c6b25e2599 (diff) | |
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.
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Duoming Zhou <duoming@zju.edu.cn>
Link: https://patch.msgid.link/20251028100149.40721-1-duoming@zju.edu.cn
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
| -rw-r--r-- | drivers/scsi/imm.c | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/drivers/scsi/imm.c b/drivers/scsi/imm.c index 5c602c057798..45b0e33293a5 100644 --- a/drivers/scsi/imm.c +++ b/drivers/scsi/imm.c @@ -1260,6 +1260,7 @@ static void imm_detach(struct parport *pb) imm_struct *dev; list_for_each_entry(dev, &imm_hosts, list) { if (dev->dev->port == pb) { + disable_delayed_work_sync(&dev->imm_tq); list_del_init(&dev->list); scsi_remove_host(dev->host); scsi_host_put(dev->host); |