CVE-2022-3437 source4/heimdal: Use constant-time memcmp() in unwrap_des3()

The surrounding checks all use ct_memcmp(), so this one was presumably
meant to as well.

BUG: https://bugzilla.samba.org/show_bug.cgi?id=15134

Signed-off-by: Joseph Sutton <josephsutton@catalyst.net.nz>
Reviewed-by: Andrew Bartlett <abartlet@samba.org>

diff --git a/source4/heimdal/lib/gssapi/krb5/unwrap.c b/source4/heimdal/lib/gssapi/krb5/unwrap.c
index b3da35ee9e28f4b374569d2acd0b8f50500ce6c2..7111a7944fe0d55c94fe9a1c06166722b0fe94f8 100644 (file)
--- a/source4/heimdal/lib/gssapi/krb5/unwrap.c
+++ b/source4/heimdal/lib/gssapi/krb5/unwrap.c
@@ -227,7 +227,7 @@ unwrap_des3
   if (ret)
       return ret;
 
-  if (memcmp (p, "\x04\x00", 2) != 0) /* HMAC SHA1 DES3_KD */
+  if (ct_memcmp (p, "\x04\x00", 2) != 0) /* HMAC SHA1 DES3_KD */
     return GSS_S_BAD_SIG;
   p += 2;
   if (ct_memcmp (p, "\x02\x00", 2) == 0) {