Building with clang may make this more likely to crash, problem is encountered on ell/tls.c:114 (before). Also, use memmove as src/dst may overlap. --- ell/tls.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/ell/tls.c b/ell/tls.c index 0e06c27..50df446 100644 --- a/ell/tls.c +++ b/ell/tls.c @@ -92,7 +92,8 @@ bool tls12_prf(enum l_checksum_type type, { struct l_checksum *hmac = l_checksum_new_hmac(type, secret, secret_len); size_t a_len, chunk_len, prfseed_len = strlen(label) + seed_len; - uint8_t a[128], prfseed[prfseed_len]; + uint8_t a[128 + prfseed_len]; + uint8_t *prfseed = &a[128]; if (!hmac) return false; @@ -108,10 +109,10 @@ bool tls12_prf(enum l_checksum_type type, /* Generate A(i) */ l_checksum_reset(hmac); l_checksum_update(hmac, a, a_len); - a_len = l_checksum_get_digest(hmac, a, sizeof(a)); + a_len = l_checksum_get_digest(hmac, a, 128); /* Append seed & generate output */ - memcpy(a + a_len, prfseed, prfseed_len); + memmove(a + a_len, prfseed, prfseed_len); l_checksum_reset(hmac); l_checksum_update(hmac, a, a_len + prfseed_len); -- 2.24.0-rc1