scsi: qla2xxx: Avoid req_q_map double-read in qla2x00_error_entry()

qla2x00_error_entry() reads ha->req_q_map[que] twice: once for the NULL
check and again when assigning it to req. The map slot is cleared by
qla25xx_free_req_que() (ha->req_q_map[que_id] = NULL under mq_lock)
during queue teardown, while the response-queue interrupt that drives
qla2x00_error_entry() is still registered (the IRQ is released later in
qla25xx_free_rsp_que()). If the slot is set to NULL between the two
reads, req becomes NULL and is dereferenced.

Read the slot once into req and NULL-check the local before use. mq_lock
is a mutex and cannot be taken from interrupt context, so the single
read plus local check is the appropriate fix for the reported NULL
dereference.

Fixes: a6fe35c052 ("[SCSI] qla2xxx: Avoid invalid request queue dereference for bad response packets.")
Cc: stable@vger.kernel.org
Reported-by: Sashiko <sashiko-dev@google.com>
Signed-off-by: Nilesh Javali <njavali@marvell.com>
Link: https://patch.msgid.link/20260730155838.2119230-17-njavali@marvell.com
Signed-off-by: Martin K. Petersen (Oracle) <mkp@kernel.org>
This commit is contained in:
Nilesh Javali 2026-07-30 21:28:21 +05:30 • committed by Martin K. Petersen (Oracle)
commit deb8abde83