scsi: lpfc: Use after free in lpfc_rq_buf_free()

[ Upstream commit 9816ef6ecbc102b9bcbb1d83e12c7fb19924f38c ]

The error message dereferences "rqb_entry" so we need to print it first
and then free the buffer.

Fixes: 6c621a2229b0 ("scsi: lpfc: Separate NVMET RQ buffer posting from IO resources SGL/iocbq/context")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Dick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/scsi/lpfc/lpfc_mem.c b/drivers/scsi/lpfc/lpfc_mem.c
index 56faeb0..87c08ff 100644 (file)
--- a/drivers/scsi/lpfc/lpfc_mem.c
+++ b/drivers/scsi/lpfc/lpfc_mem.c
@@ -753,12 +753,12 @@ lpfc_rq_buf_free(struct lpfc_hba *phba, struct lpfc_dmabuf *mp)
        drqe.address_hi = putPaddrHigh(rqb_entry->dbuf.phys);
        rc = lpfc_sli4_rq_put(rqb_entry->hrq, rqb_entry->drq, &hrqe, &drqe);
        if (rc < 0) {
-               (rqbp->rqb_free_buffer)(phba, rqb_entry);
                lpfc_printf_log(phba, KERN_ERR, LOG_INIT,
                                "6409 Cannot post to RQ %d: %x %x\n",
                                rqb_entry->hrq->queue_id,
                                rqb_entry->hrq->host_index,
                                rqb_entry->hrq->hba_index);
+               (rqbp->rqb_free_buffer)(phba, rqb_entry);
        } else {
                list_add_tail(&rqb_entry->hbuf.list, &rqbp->rqb_buffer_list);
                rqbp->buffer_count++;