From 87ae95eb3c2f35d3e8e00eca43d0711ab2737ef5 Mon Sep 17 00:00:00 2001 From: Jon Simons Date: Sat, 18 Oct 2014 23:23:26 -0700 Subject: [PATCH] CVE-2014-8132: Fixup error path in ssh_packet_kexinit() Before this change, dangling pointers can be unintentionally left in the respective next_crypto kex methods slots. Ensure to set all slots to NULL in the error-out path. Signed-off-by: Jon Simons Reviewed-by: Andreas Schneider (cherry picked from commit 2ced24ddd67a261dc364ad4d8958c068c1671ae7) --- src/kex.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/src/kex.c b/src/kex.c index 563c6a57..fab6badf 100644 --- a/src/kex.c +++ b/src/kex.c @@ -315,7 +315,7 @@ SSH_PACKET_CALLBACK(ssh_packet_kexinit){ for (i = 0; i < KEX_METHODS_SIZE; i++) { str = buffer_get_ssh_string(packet); if (str == NULL) { - break; + goto error; } if (buffer_add_ssh_string(session->in_hashbuf, str) < 0) { @@ -350,6 +350,11 @@ SSH_PACKET_CALLBACK(ssh_packet_kexinit){ error: ssh_string_free(str); for (i = 0; i < SSH_KEX_METHODS; i++) { + if (server_kex) { + session->next_crypto->client_kex.methods[i] = NULL; + } else { /* client */ + session->next_crypto->server_kex.methods[i] = NULL; + } SAFE_FREE(strings[i]); }