[CRIU] [PATCHv2 2/2] zdtm: sysctl net.unix.max_dgram_qlen value preservation test

[Alexander Mikhalitsyn]

Test checks that if the /proc/sys/net/unix/max_dgram_qlen value has
been changed in process net namespace, then it is saved after c/r.

Based-on-patch-by: Cyrill Gorcunov <gorcunov at gmail.com>
Signed-off-by: Alexander Mikhalitsyn <alexander at mihalicyn.com>
---
 test/zdtm/static/Makefile              |  1 +
 test/zdtm/static/netns_sub_sysctl.c    | 52 ++++++++++++++++++++++++++
 test/zdtm/static/netns_sub_sysctl.desc |  5 +++
 3 files changed, 58 insertions(+)
 create mode 100644 test/zdtm/static/netns_sub_sysctl.c
 create mode 100644 test/zdtm/static/netns_sub_sysctl.desc

diff --git a/test/zdtm/static/Makefile b/test/zdtm/static/Makefile
index a38482f4..887bf4ac 100644
--- a/test/zdtm/static/Makefile
+++ b/test/zdtm/static/Makefile
@@ -207,6 +207,7 @@ TST_NOFILE	:=				\
 		pipe03				\
 		netns_sub			\
 		netns_sub_veth			\
+		netns_sub_sysctl	\
 		unlink_multiple_largefiles	\
 		config_inotify_irmap		\
 		thp_disable			\
diff --git a/test/zdtm/static/netns_sub_sysctl.c b/test/zdtm/static/netns_sub_sysctl.c
new file mode 100644
index 00000000..6a816c53
--- /dev/null
+++ b/test/zdtm/static/netns_sub_sysctl.c
@@ -0,0 +1,52 @@
+#include <sched.h>
+#include <errno.h>
+#include <stdlib.h>
+
+#include "zdtmtst.h"
+
+const char *test_doc	= "Check dump and restore a net.unix.max_dgram_qlen sysctl parameter in subns";
+
+#define CONF_UNIX_PARAM "/proc/sys/net/unix/max_dgram_qlen"
+
+int main(int argc, char **argv)
+{
+	char cmd[128];
+	FILE *fp;
+	int ret, test_max_dgram_qlen = 321, max_dgram_qlen = 0;
+	test_init(argc, argv);
+
+	if (unshare(CLONE_NEWNET)) {
+		perror("unshare");
+		return 1;
+	}
+
+	sprintf(cmd, "echo %d > %s", test_max_dgram_qlen, CONF_UNIX_PARAM);
+	if (system(cmd)) {
+		pr_perror("Can't change %s", CONF_UNIX_PARAM);
+		return -1;
+	}
+
+	test_daemon();
+	test_waitsig();
+
+	fp = fopen(CONF_UNIX_PARAM, "r+");
+	if (fp == NULL) {
+		pr_perror("fopen");
+		return -1;
+	}
+
+	ret = fscanf(fp, "%d", &max_dgram_qlen);
+	if (ret != 1) {
+		pr_perror("fscanf");
+		fclose(fp);
+		return -1;
+	}
+
+	if (test_max_dgram_qlen != max_dgram_qlen) {
+		fail();
+		return 1;
+	}
+
+	pass();
+	return 0;
+}
diff --git a/test/zdtm/static/netns_sub_sysctl.desc b/test/zdtm/static/netns_sub_sysctl.desc
new file mode 100644
index 00000000..e13a65b6
--- /dev/null
+++ b/test/zdtm/static/netns_sub_sysctl.desc
@@ -0,0 +1,5 @@
+{
+    'deps': ['/bin/sh', '/sbin/ip|/bin/ip'],
+    'flavor': 'ns',
+    'flags': 'suid'
+}
-- 
2.17.1