daemon/tls_ephemeral_credentials: fix possible race between read() and fstat()

diff --git a/daemon/tls_ephemeral_credentials.c b/daemon/tls_ephemeral_credentials.c
index 0d9ec6db6453bb3685b66e853261b41dd27618e4..2b928faaad04bbd0b949606b034f35b5a66ccd0f 100644 (file)
--- a/daemon/tls_ephemeral_credentials.c
+++ b/daemon/tls_ephemeral_credentials.c
@@ -91,7 +91,7 @@ static gnutls_x509_privkey_t get_ephemeral_privkey (void)
                }
                data.size = stat.st_size;
                bytes_read = read(datafd, data.data, stat.st_size);
-               if (bytes_read != stat.st_size) {
+               if (bytes_read < 0 || bytes_read != stat.st_size) {
                        kr_log_error(TLS, "unable to read ephemeral private key\n");
                        goto bad_data;
                }