diff options
| author | Duoming Zhou <duoming@zju.edu.cn> | 2025-10-28 18:01:49 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2025-12-18 14:00:15 +0100 |
| commit | 48dd41fa2d6c6a0c50e714deeba06ffe7f91961b (patch) | |
| tree | 6be831b6a7e81b0f22d284bd39fba99e706dd113 | |
| parent | 40e646ed350c138c1cd93c48a79a55554d0f0797 (diff) | |
scsi: imm: Fix use-after-free bug caused by unfinished delayed work
[ Upstream commit ab58153ec64fa3fc9aea09ca09dc9322e0b54a7c ]
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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
| -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 0821cf994b98..8a099bc27e06 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); |