From 6c7f9703e42bc5278d0a4a6f0a39d07d62123ea3 Mon Sep 17 00:00:00 2001 From: Daiki Ueno Date: Tue, 31 Mar 2020 06:58:48 +0200 Subject: [PATCH 2/3] build: use valgrind client request to detect undefined memory use commit 50ad8778a81f9421effa4c5a3b457f98e559b178 from https://gitlab.com/gnutls/gnutls.git This tightens the check introduced in ac2f71b892d13a7ab4cc39086eef179042c7e23c, by using the valgrind client request to explicitly mark the "uninitialized but initialization is needed before use" regions. With this patch and the fix (c01011c2d8533dbbbe754e49e256c109cb848d0d) reverted, you will see the following error when running dtls_hello_random_value under valgrind: $ valgrind ./dtls_hello_random_value testing: default ==520145== Conditional jump or move depends on uninitialised value(s) ==520145== at 0x4025F5: hello_callback (dtls_hello_random_value.c:90) ==520145== by 0x488BF97: _gnutls_call_hook_func (handshake.c:1215) ==520145== by 0x488C1AA: _gnutls_send_handshake2 (handshake.c:1332) ==520145== by 0x488FC7E: send_client_hello (handshake.c:2290) ==520145== by 0x48902A1: handshake_client (handshake.c:2908) ==520145== by 0x48902A1: gnutls_handshake (handshake.c:2740) ==520145== by 0x402CB3: client (dtls_hello_random_value.c:153) ==520145== by 0x402CB3: start (dtls_hello_random_value.c:317) ==520145== by 0x402EFE: doit (dtls_hello_random_value.c:331) ==520145== by 0x4023D4: main (utils.c:254) ==520145== Upstream-Status: Backport Signed-off-by: Daiki Ueno Signed-off-by: Haiqing Bai --- configure.ac | 2 ++ lib/handshake.c | 15 +++++++++++++++ lib/state.c | 21 ++++++++++++++++++--- 3 files changed, 35 insertions(+), 3 deletions(-) diff --git a/configure.ac b/configure.ac index 172cf42..12da283 100644 --- a/configure.ac +++ b/configure.ac @@ -233,6 +233,8 @@ AS_IF([test "$ac_cv_search___atomic_load_4" = "none required" || test "$ac_cv_se dnl We use its presence to detect C11 threads AC_CHECK_HEADERS([threads.h]) +AC_CHECK_HEADERS([valgrind/memcheck.h]) + AC_ARG_ENABLE(padlock, AS_HELP_STRING([--disable-padlock], [unconditionally disable padlock acceleration]), use_padlock=$enableval) diff --git a/lib/handshake.c b/lib/handshake.c index 84a0e52..8d58fa4 100644 --- a/lib/handshake.c +++ b/lib/handshake.c @@ -57,6 +57,9 @@ #include "secrets.h" #include "tls13/session_ticket.h" #include "locks.h" +#ifdef HAVE_VALGRIND_MEMCHECK_H +#include +#endif #define TRUE 1 #define FALSE 0 @@ -242,6 +245,12 @@ int _gnutls_gen_client_random(gnutls_session_t session) return gnutls_assert_val(ret); } +#ifdef HAVE_VALGRIND_MEMCHECK_H + if (RUNNING_ON_VALGRIND) + VALGRIND_MAKE_MEM_DEFINED(session->security_parameters.client_random, + GNUTLS_RANDOM_SIZE); +#endif + return 0; } @@ -320,6 +329,12 @@ int _gnutls_gen_server_random(gnutls_session_t session, int version) return ret; } +#ifdef HAVE_VALGRIND_MEMCHECK_H + if (RUNNING_ON_VALGRIND) + VALGRIND_MAKE_MEM_DEFINED(session->security_parameters.server_random, + GNUTLS_RANDOM_SIZE); +#endif + return 0; } diff --git a/lib/state.c b/lib/state.c index 0e1d155..98900c1 100644 --- a/lib/state.c +++ b/lib/state.c @@ -55,6 +55,9 @@ #include "ext/cert_types.h" #include "locks.h" #include "kx.h" +#ifdef HAVE_VALGRIND_MEMCHECK_H +#include +#endif /* to be used by supplemental data support to disable TLS1.3 * when supplemental data have been globally registered */ @@ -564,10 +567,22 @@ int gnutls_init(gnutls_session_t * session, unsigned int flags) UINT32_MAX; } - /* everything else not initialized here is initialized - * as NULL or 0. This is why calloc is used. + /* Everything else not initialized here is initialized as NULL + * or 0. This is why calloc is used. However, we want to + * ensure that certain portions of data are initialized at + * runtime before being used. Mark such regions with a + * valgrind client request as undefined. */ - +#ifdef HAVE_VALGRIND_MEMCHECK_H + if (RUNNING_ON_VALGRIND) { + if (flags & GNUTLS_CLIENT) + VALGRIND_MAKE_MEM_UNDEFINED((*session)->security_parameters.client_random, + GNUTLS_RANDOM_SIZE); + if (flags & GNUTLS_SERVER) + VALGRIND_MAKE_MEM_UNDEFINED((*session)->security_parameters.server_random, + GNUTLS_RANDOM_SIZE); + } +#endif handshake_internal_state_clear1(*session); #ifdef HAVE_WRITEV -- 2.17.1