ah: use crypto_memneq to check the ICV

Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
diff --git a/net/ipv6/ah6.c b/net/ipv6/ah6.c
index dda6035..ac747b1 100644
--- a/net/ipv6/ah6.c
+++ b/net/ipv6/ah6.c
@@ -25,6 +25,7 @@
 
 #define pr_fmt(fmt) "IPv6: " fmt
 
+#include <crypto/algapi.h>
 #include <crypto/hash.h>
 #include <linux/module.h>
 #include <linux/slab.h>
@@ -481,7 +482,7 @@
 	auth_data = ah_tmp_auth(work_iph, hdr_len);
 	icv = ah_tmp_icv(ahp->ahash, auth_data, ahp->icv_trunc_len);
 
-	err = memcmp(icv, auth_data, ahp->icv_trunc_len) ? -EBADMSG : 0;
+	err = crypto_memneq(icv, auth_data, ahp->icv_trunc_len) ? -EBADMSG : 0;
 	if (err)
 		goto out;
 
@@ -627,7 +628,7 @@
 		goto out_free;
 	}
 
-	err = memcmp(icv, auth_data, ahp->icv_trunc_len) ? -EBADMSG : 0;
+	err = crypto_memneq(icv, auth_data, ahp->icv_trunc_len) ? -EBADMSG : 0;
 	if (err)
 		goto out_free;