xfrm: use memcpy to suppress gcc phony buffer overflow warning.

This bug is reported from below link:
https://bugzilla.redhat.com/show_bug.cgi?id=982761

An simplified command from its original reproducing method in bugzilla:
ip xfrm state add src 10.0.0.2 dst 10.0.0.1 proto ah spi 0x12345678 auth md5 12
will cause below spew from gcc.

Reported-by: Sohny Thomas <sthomas@linux.vnet.ibm.com>

diff --git a/ip/xfrm_state.c b/ip/xfrm_state.c
index 389942c03215c1a02fe47bd5a848033367917bf8..f4ad4cb15108cf71d4970342676e7f69416ba388 100644 (file)
--- a/ip/xfrm_state.c
+++ b/ip/xfrm_state.c
@@ -162,7 +162,7 @@ static int xfrm_algo_parse(struct xfrm_algo *alg, enum xfrm_attr_type_t type,
                        if (len > max)
                                invarg("ALGO-KEYMAT value makes buffer overflow\n", key);
 
-                       strncpy(buf, key, len);
+                       memcpy(buf, key, len);
                }
        }