[PATCH 4.5 121/200] IB/core: Fix oops in ib_cache_gid_set_default_gid

[Greg Kroah-Hartman]

4.5-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Doug Ledford <dledford@xxxxxxxxxx>

commit f4e7de63ab273b6a5e35c82eb4fc6363c855ddd4 upstream.

When we fail to find the default gid index, we can't continue
processing in this routine or else we will pass a negative
index to later routines resulting in invalid memory access
attempts and a kernel oops.

Fixes: 03db3a2d81e6 (IB/core: Add RoCE GID table management)
Signed-off-by: Doug Ledford <dledford@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/infiniband/core/cache.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

--- a/drivers/infiniband/core/cache.c
+++ b/drivers/infiniband/core/cache.c
@@ -691,7 +691,8 @@ void ib_cache_gid_set_default_gid(struct
 			      NULL);
 
 		/* Coudn't find default GID location */
-		WARN_ON(ix < 0);
+		if (WARN_ON(ix < 0))
+			goto release;
 
 		zattr_type.gid_type = gid_type;