[SCSI] target: Fix match_strdup() memory leaks

match_strdup() dynamically allocates memory and it is the responsabillity
of the caller to free that memory. The following three cases:

drivers/target/target_core_file.c:fd_set_configfs_dev_params()
drivers/target/target_core_iblock.c:iblock_set_configfs_dev_params()
drivers/target/target_core_configfs.c:target_core_dev_pr_store_attr_res_aptpl_metadata()

should be kfree()'ing the allocated memory once it is no longer needed.
It also makes sure to return -ENOMEM if the memory allocation in match_strdup()
should fail.  For target_core_configfs.c, this patch adds kfree()'s around
Opt_initiator_fabric, Opt_initiator_node, Opt_initiator_sid, Opt_sa_res_key,
Opt_target_fabric, and Opt_target_node for the Persistent Reservations
Activate Persistence across Target Power Loss (APTPL=1) token parsing.

Signed-off-by: Jesper Juhl <jj@chaosbits.net>
Signed-off-by: Nicholas A. Bellinger <nab@linux-iscsi.org>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
diff --git a/drivers/target/target_core_iblock.c b/drivers/target/target_core_iblock.c
index 3df570d..96d98cc 100644
--- a/drivers/target/target_core_iblock.c
+++ b/drivers/target/target_core_iblock.c
@@ -468,7 +468,7 @@
 					       const char *page, ssize_t count)
 {
 	struct iblock_dev *ib_dev = se_dev->se_dev_su_ptr;
-	char *orig, *ptr, *opts;
+	char *orig, *ptr, *arg_p, *opts;
 	substring_t args[MAX_OPT_ARGS];
 	int ret = 0, arg, token;
 
@@ -491,9 +491,14 @@
 				ret = -EEXIST;
 				goto out;
 			}
-
-			ret = snprintf(ib_dev->ibd_udev_path, SE_UDEV_PATH_LEN,
-				"%s", match_strdup(&args[0]));
+			arg_p = match_strdup(&args[0]);
+			if (!arg_p) {
+				ret = -ENOMEM;
+				break;
+			}
+			snprintf(ib_dev->ibd_udev_path, SE_UDEV_PATH_LEN,
+					"%s", arg_p);
+			kfree(arg_p);
 			printk(KERN_INFO "IBLOCK: Referencing UDEV path: %s\n",
 					ib_dev->ibd_udev_path);
 			ib_dev->ibd_flags |= IBDF_HAS_UDEV_PATH;