CVE-2013-4408:s4:dcerpc_smb: check for invalid frag_len in send_read_request_continue()

Bug: https://bugzilla.samba.org/show_bug.cgi?id=10185

Signed-off-by: Stefan Metzmacher <metze@samba.org>
Reviewed-by: Jeremy Allison <jra@samba.org>

diff --git a/source4/librpc/rpc/dcerpc_smb.c b/source4/librpc/rpc/dcerpc_smb.c
index 395e0672558a57f3e3ad3b9504b8a590deb5ba2a..61cf791625e047b420f7dc29c2b302030364b896 100644 (file)
--- a/source4/librpc/rpc/dcerpc_smb.c
+++ b/source4/librpc/rpc/dcerpc_smb.c
@@ -160,6 +160,12 @@ static NTSTATUS send_read_request_continue(struct dcecli_connection *c, DATA_BLO
        } else {
                uint32_t frag_length = blob->length>=16?
                        dcerpc_get_frag_length(blob):0x2000;
+
+               if (frag_length < state->data.length) {
+                       talloc_free(state);
+                       return NT_STATUS_RPC_PROTOCOL_ERROR;
+               }
+
                state->received = blob->length;
                state->data = data_blob_talloc(state, NULL, frag_length);
                if (!state->data.data) {