[SCM] Socket Wrapper Repository - branch master updated

[Michael Adam]

The branch, master has been updated
       via  5af1553 Avoid mutex lock wait in socket close failure
      from  888a62e swrap: Add sanity check in socket_wrapper_max_sockets()

https://git.samba.org/?p=socket_wrapper.git;a=shortlog;h=master


- Log -----------------------------------------------------------------
commit 5af15532cefecb5665736f30e00960c17700d1b0
Author: Anoop C S <anoopcs at redhat.com>
Date:   Fri Feb 10 21:38:11 2017 +0530

    Avoid mutex lock wait in socket close failure
    
    In case of absence to close a socket fd during an exit from
    application we try to close the same by traversing the
    socket_fds in swrap_destructor. But the early lock taken on
    libc_symbol_binding_mutex inside the destructor blocks the
    subsequent request for locking the same while loading
    libc_close within swrap_close.
    
    Also added a test case to verify this flaw in destructor.
    
    Signed-off-by: Anoop C S <anoopcs at redhat.com>
    Reviewed-by: Andreas Schneider <asn at samba.org>
    Reviewed-by: Michael Adam <obnox at samba.org>

-----------------------------------------------------------------------

Summary of changes:
 src/socket_wrapper.c       |  4 ----
 tests/CMakeLists.txt       |  3 ++-
 tests/test_close_failure.c | 50 ++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 52 insertions(+), 5 deletions(-)
 create mode 100644 tests/test_close_failure.c


Changeset truncated at 500 lines:

diff --git a/src/socket_wrapper.c b/src/socket_wrapper.c
index 186b696..3d468c3 100644
--- a/src/socket_wrapper.c
+++ b/src/socket_wrapper.c
@@ -5656,8 +5656,6 @@ void swrap_destructor(void)
 {
 	struct socket_info_fd *s = socket_fds;
 
-	SWRAP_LOCK_ALL;
-
 	while (s != NULL) {
 		swrap_close(s->fd);
 		s = socket_fds;
@@ -5671,6 +5669,4 @@ void swrap_destructor(void)
 	if (swrap.libc.socket_handle) {
 		dlclose(swrap.libc.socket_handle);
 	}
-
-	SWRAP_UNLOCK_ALL;
 }
diff --git a/tests/CMakeLists.txt b/tests/CMakeLists.txt
index 9292b40..c2bd799 100644
--- a/tests/CMakeLists.txt
+++ b/tests/CMakeLists.txt
@@ -35,7 +35,8 @@ set(SWRAP_TESTS
     test_echo_udp_send_recv
     test_echo_udp_sendmsg_recvmsg
     test_swrap_unit
-    test_max_sockets)
+    test_max_sockets
+    test_close_failure)
 
 if (HAVE_STRUCT_MSGHDR_MSG_CONTROL)
     set(SWRAP_TESTS ${SWRAP_TESTS} test_sendmsg_recvmsg_fd)
diff --git a/tests/test_close_failure.c b/tests/test_close_failure.c
new file mode 100644
index 0000000..0c9d6a7
--- /dev/null
+++ b/tests/test_close_failure.c
@@ -0,0 +1,50 @@
+#include "torture.h"
+
+#include <errno.h>
+#include <stdio.h>
+#include <cmocka.h>
+#include <unistd.h>
+#include <stdlib.h>
+
+static int setup(void **state)
+{
+	torture_setup_socket_dir(state);
+
+	return 0;
+}
+
+static int teardown(void **state)
+{
+	torture_teardown_socket_dir(state);
+
+	return 0;
+}
+
+static void test_close_failure(void **state)
+{
+	int s;
+	int rc;
+
+	(void) state; /* unused */
+	(void) s; /*set but not used */
+
+	s = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
+
+	assert_int_not_equal(rc, -1);
+
+	/* Do not close the socket here so that destructor
+	 * handles it and no hang should be observed.*/
+}
+
+int main(void) {
+	int rc;
+
+	const struct CMUnitTest close_failure_tests[] = {
+		cmocka_unit_test_setup_teardown(test_close_failure,
+						setup, teardown),
+	};
+
+	rc = cmocka_run_group_tests(close_failure_tests, NULL, NULL);
+
+	return rc;
+}


-- 
Socket Wrapper Repository