scsi: elx: efct: Fix memory leak in efct_hw_parse_filter()

[ Upstream commit 2a8a5a5dd06eef580f9818567773fd75057cb875 ]

strsep() modifies the address of the pointer passed to it so that it no
longer points to the original address. This means kfree() gets the wrong
pointer.

Fix this by passing unmodified pointer returned from kstrdup() to
kfree().

Found by Linux Verification Center (linuxtesting.org) with Svace.

Fixes: 4df84e8 ("scsi: elx: efct: Driver initialization routines")
Signed-off-by: Vitaliy Shevtsov <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Reviewed-by: Daniel Wagner <[email protected]>
Signed-off-by: Martin K. Petersen <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
(cherry picked from commit a77d0a14ed4740fb4d9fe089dc1176a2eab012ff)

Author: Vitaliy Shevtsov

drivers/scsi/elx/efct/efct_hw.c

@@ -1120,7 +1120,7 @@ int
 efct_hw_parse_filter(struct efct_hw *hw, void *value)
 {
 	int rc = 0;
-	char *p = NULL;
+	char *p = NULL, *pp = NULL;
 	char *token;
 	u32 idx = 0;
 
@@ -1132,6 +1132,7 @@ efct_hw_parse_filter(struct efct_hw *hw, void *value)
 		efc_log_err(hw->os, "p is NULL\n");
 		return -ENOMEM;
 	}
+	pp = p;
 
 	idx = 0;
 	while ((token = strsep(&p, ",")) && *token) {
@@ -1144,7 +1145,7 @@ efct_hw_parse_filter(struct efct_hw *hw, void *value)
 		if (idx == ARRAY_SIZE(hw->config.filter_def))
 			break;
 	}
-	kfree(p);
+	kfree(pp);
 
 	return rc;
 }