dm mpath: validate hw_handler argument count
Fix arg count parsing error in hw handlers.
Cc: stable@kernel.org
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
diff --git a/drivers/md/dm-mpath.c b/drivers/md/dm-mpath.c
index d880299..f25bdeb 100644
--- a/drivers/md/dm-mpath.c
+++ b/drivers/md/dm-mpath.c
@@ -705,6 +705,11 @@
if (!hw_argc)
return 0;
+ if (hw_argc > as->argc) {
+ ti->error = "not enough arguments for hardware handler";
+ return -EINVAL;
+ }
+
m->hw_handler_name = kstrdup(shift(as), GFP_KERNEL);
request_module("scsi_dh_%s", m->hw_handler_name);
if (scsi_dh_handler_exist(m->hw_handler_name) == 0) {