[LTP] [PATCH v2] syscalls/add_key05: Add userdel and groupdel before useradd

[Zhao Gongyi]

If the test exit abnormal, some user/group will be left, and the
next running of the test will fail and report:

  tst_buffers.c:55: TINFO: Test is using guarded buffers
  tst_test.c:1526: TINFO: Timeout per run is 0h 00m 30s
  useradd: group ltp_add_key05_0 exists - if you want to add this user to that group, use -g.
  add_key05.c:41: TBROK: useradd failed (9)
  userdel: user 'ltp_add_key05_0' does not exist
  add_key05.c:56: TWARN: 'userdel -r ltp_add_key05_0' failed: ENOENT (2)

Signed-off-by: Zhao Gongyi <zhaogongyi@huawei.com>
---
 testcases/kernel/syscalls/add_key/add_key05.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/testcases/kernel/syscalls/add_key/add_key05.c b/testcases/kernel/syscalls/add_key/add_key05.c
index 71a88d1a8..e8d249040 100644
--- a/testcases/kernel/syscalls/add_key/add_key05.c
+++ b/testcases/kernel/syscalls/add_key/add_key05.c
@@ -34,10 +34,15 @@ static void add_user(char n)
 {
 	char username[] = "ltp_add_key05_n";
 	const char *const cmd_useradd[] = {"useradd", username, NULL};
+	const char *const cmd_userdel[] = {"userdel", "-r", username, NULL};
+	const char *const cmd_groupdel[] = {"groupdel", username, NULL};
 	struct passwd *pw;

 	username[sizeof(username) - 2] = '0' + n;

+	tst_cmd(cmd_userdel, NULL, "/dev/null", TST_CMD_PASS_RETVAL);
+	tst_cmd(cmd_groupdel, NULL, "/dev/null", TST_CMD_PASS_RETVAL);
+
 	SAFE_CMD(cmd_useradd, NULL, NULL);
 	pw = SAFE_GETPWNAM(username);
 	ltpuser[(unsigned int)n] = pw->pw_uid;
--
2.17.1