upstream: fix some memory leaks spotted by Coverity via Jakub Jelen

in bz#2366 feedback and ok dtucker@

OpenBSD-Commit-ID: 8402bbae67d578bedbadb0ce68ff7c5a136ef563

1 files changed, 33 insertions, 18 deletions

diff --git a/compat.c b/compat.c
index d0afe9084..563e13331 100644
--- a/compat.c
+++ b/compat.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: compat.c,v 1.111 2018/07/09 21:03:30 markus Exp $ */
+/* $OpenBSD: compat.c,v 1.112 2018/07/31 03:07:24 djm Exp $ */
 /*
  * Copyright (c) 1999, 2000, 2001, 2002 Markus Friedl.  All rights reserved.
  *
@@ -184,13 +184,17 @@ proto_spec(const char *spec)
 }
 
 char *
-compat_cipher_proposal(char *cipher_prop)
+compat_cipher_proposal(char *cipher_prop, u_int compat)
 {
-        if (!(datafellows & SSH_BUG_BIGENDIANAES))
+        char *cp;
+
+        if (!(compat & SSH_BUG_BIGENDIANAES))
                 return cipher_prop;
         debug2("%s: original cipher proposal: %s", __func__, cipher_prop);
-        if ((cipher_prop = match_filter_blacklist(cipher_prop, "aes*")) == NULL)
+        if ((cp = match_filter_blacklist(cipher_prop, "aes*")) == NULL)
                 fatal("match_filter_blacklist failed");
+        free(cipher_prop);
+        cipher_prop = cp;
         debug2("%s: compat cipher proposal: %s", __func__, cipher_prop);
         if (*cipher_prop == '\0')
                 fatal("No supported ciphers found");
@@ -198,13 +202,17 @@ compat_cipher_proposal(char *cipher_prop)
 }
 
 char *
-compat_pkalg_proposal(char *pkalg_prop)
+compat_pkalg_proposal(char *pkalg_prop, u_int compat)
 {
-        if (!(datafellows & SSH_BUG_RSASIGMD5))
+        char *cp;
+
+        if (!(compat & SSH_BUG_RSASIGMD5))
                 return pkalg_prop;
         debug2("%s: original public key proposal: %s", __func__, pkalg_prop);
-        if ((pkalg_prop = match_filter_blacklist(pkalg_prop, "ssh-rsa")) == NULL)
+        if ((cp = match_filter_blacklist(pkalg_prop, "ssh-rsa")) == NULL)
                 fatal("match_filter_blacklist failed");
+        free(pkalg_prop);
+        pkalg_prop = cp;
         debug2("%s: compat public key proposal: %s", __func__, pkalg_prop);
         if (*pkalg_prop == '\0')
                 fatal("No supported PK algorithms found");
@@ -212,24 +220,31 @@ compat_pkalg_proposal(char *pkalg_prop)
 }
 
 char *
-compat_kex_proposal(char *p)
+compat_kex_proposal(char *kex_prop, u_int compat)
 {
-        if ((datafellows & (SSH_BUG_CURVE25519PAD|SSH_OLD_DHGEX)) == 0)
-                return p;
-        debug2("%s: original KEX proposal: %s", __func__, p);
-        if ((datafellows & SSH_BUG_CURVE25519PAD) != 0)
-                if ((p = match_filter_blacklist(p,
+        char *cp;
+
+        if ((compat & (SSH_BUG_CURVE25519PAD|SSH_OLD_DHGEX)) == 0)
+                return kex_prop;
+        debug2("%s: original KEX proposal: %s", __func__, kex_prop);
+        if ((compat & SSH_BUG_CURVE25519PAD) != 0) {
+                if ((cp = match_filter_blacklist(kex_prop,
                     "curve25519-sha256@libssh.org")) == NULL)
                         fatal("match_filter_blacklist failed");
-        if ((datafellows & SSH_OLD_DHGEX) != 0) {
-                if ((p = match_filter_blacklist(p,
+                free(kex_prop);
+                kex_prop = cp;
+        }
+        if ((compat & SSH_OLD_DHGEX) != 0) {
+                if ((cp = match_filter_blacklist(kex_prop,
                     "diffie-hellman-group-exchange-sha256,"
                     "diffie-hellman-group-exchange-sha1")) == NULL)
                         fatal("match_filter_blacklist failed");
+                free(kex_prop);
+                kex_prop = cp;
         }
-        debug2("%s: compat KEX proposal: %s", __func__, p);
-        if (*p == '\0')
+        debug2("%s: compat KEX proposal: %s", __func__, kex_prop);
+        if (*kex_prop == '\0')
                 fatal("No supported key exchange algorithms found");
-        return p;
+        return kex_prop;
 }