[PATCH 26/33] scsi: qla2xxx: Unlink NVMe unsol ctx before freeing on LS reject error

qla_nvme_xmt_ls_rsp() obtains uctx, which was linked into
fcport->unsol_ctx_head by qla2xxx_process_purls_iocb() and is still linked
when the NVMe transport calls back to transmit the LS response. On the
error (out:) path the function frees uctx with kfree() but never removes
it from the list. This leaves a freed node in fcport->unsol_ctx_head: the
next list_add_tail() for that fcport writes through the freed node, and a
subsequent list_del() can corrupt the list or panic.

Unlink uctx with list_del() before kfree() on the error path, matching the
other free sites in qla_nvme_release_lsrsp_cmd_kref() and
qla2xxx_process_purls_pkt(). qla2x00_rel_sp() in the failure path only
returns the SRB to its pool and does not invoke sp->put_fn, so the out:
path is the sole free and uctx is always still linked there.

Fixes: 875386b98857 ("scsi: qla2xxx: Add Unsolicited LS Request and Response Support for NVMe")
Cc: [email protected]
Reported-by: Sashiko <[email protected]>
Signed-off-by: Nilesh Javali <[email protected]>
---
 drivers/scsi/qla2xxx/qla_nvme.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/scsi/qla2xxx/qla_nvme.c b/drivers/scsi/qla2xxx/qla_nvme.c
index 28a04e0ff660..36b742f73abf 100644
--- a/drivers/scsi/qla2xxx/qla_nvme.c
+++ b/drivers/scsi/qla2xxx/qla_nvme.c
@@ -446,6 +446,7 @@ static int qla_nvme_xmt_ls_rsp(struct nvme_fc_local_port *lport,
 		qla_nvme_ls_reject_iocb(vha, ha->base_qpair, &a, true);
 		spin_unlock_irqrestore(ha->base_qpair->qp_lock_ptr, flags);
 	}
+	list_del(&uctx->elem);
 	kfree(uctx);
 	return rval;
 }
-- 
2.47.3