From ad5a165f94f087d04a648e56839227fcbafa00d5 Mon Sep 17 00:00:00 2001
From: Frank Denis <github@pureftpd.org>
Date: Sun, 21 Sep 2014 22:06:45 -0700
Subject: [PATCH] crypto_sign(): read the copy, not the message, to properly
 handle overlaps

---
 src/libsodium/crypto_sign/ed25519/ref10/sign.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/libsodium/crypto_sign/ed25519/ref10/sign.c b/src/libsodium/crypto_sign/ed25519/ref10/sign.c
index 80f64955..1ee5d6c4 100644
--- a/src/libsodium/crypto_sign/ed25519/ref10/sign.c
+++ b/src/libsodium/crypto_sign/ed25519/ref10/sign.c
@@ -63,7 +63,8 @@ crypto_sign(unsigned char *sm, unsigned long long *smlen,
 
     memmove(sm + crypto_sign_ed25519_BYTES, m, mlen);
 /* LCOV_EXCL_START */
-    if (crypto_sign_detached(sm, &siglen, m, mlen, sk) != 0 ||
+    if (crypto_sign_detached(sm, &siglen, sm + crypto_sign_ed25519_BYTES,
+                             mlen, sk) != 0 ||
         siglen != crypto_sign_ed25519_BYTES) {
         if (smlen != NULL) {
             *smlen = 0;