diff mbox series

[v2,05/10] Rewrite semtest_2ns.c using new LTP API

Message ID 20220310105916.7960-6-andrea.cervesato@suse.de
State Superseded
Headers show
Series Rewrite sysvipc testing suite using new LTP API | expand

Commit Message

Andrea Cervesato March 10, 2022, 10:59 a.m. UTC 
Signed-off-by: Andrea Cervesato <andrea.cervesato@suse.de>
---
 .../kernel/containers/sysvipc/semtest_2ns.c   | 295 +++++++-----------
 1 file changed, 107 insertions(+), 188 deletions(-)

Comments

Cyril Hrubis March 10, 2022, 4:37 p.m. UTC | #1 
Hi!
> +/*\
> + * [Description]
> + *
> + * Test SysV IPC semaphore usage between namespaces.
> + *
> + * [Algorithm]
> + *
> + * Create 2 'containers'
> + * In container1 create semaphore with a specific key
> + * In container2 try to access the semaphore created in container1
> + *
> + * Test is PASS if flag = none and the semaphore is accessible in container2 or
> + * if flag = unshare/clone and the semaphore is not accessible in container2.
> + * If semaphore is not accessible in container2, creates new semaphore with the
> + * same key to double check isloation in IPCNS.
> + *
> + * Test is FAIL if flag = none and the semaphore is not accessible, if
> + * flag = unshare/clone and semaphore is accessible in container2 or if the new
> + * semaphore creation Fails.
> + */
> +
> +#define _GNU_SOURCE
> +
> +#include <sys/wait.h>
> +#include <sys/msg.h>
> +#include <sys/types.h>
>  #include <sys/sem.h>
> -#include <libclone.h>
> -#include "test.h"
> -#include "ipcns_helper.h"
> -
> -#define MY_KEY     124326L
> -#define UNSHARESTR "unshare"
> -#define CLONESTR   "clone"
> -#define NONESTR    "none"
> -
> -char *TCID = "semtest_2ns";
> -int TST_TOTAL = 1;
> -int p1[2];
> -int p2[2];
> +#include "tst_safe_sysv_ipc.h"
> +#include "tst_test.h"
> +#include "common.h"
> +
> +#define MY_KEY 124326L
> +
> +static char *str_op = "clone";
> +static int use_clone;
> +
>  static struct sembuf semop_lock[2] = {
>  	/* sem_num, sem_op, flag */
> -	{0, 0, 0},		/* wait for sem#0 to become 0 */
> -	{0, 1, SEM_UNDO}	/* then increment sem#0 by 1 */
> +	{ 0, 0, 0 }, /* wait for sem#0 to become 0 */
> +	{ 0, 1, SEM_UNDO } /* then increment sem#0 by 1 */
>  };
>  
>  static struct sembuf semop_unlock[1] = {
>  	/* sem_num, sem_op, flag */
> -	{0, -1, (IPC_NOWAIT | SEM_UNDO)}	/* decrement sem#0 by 1 (sets it to 0) */
> +	{ 0, -1, (IPC_NOWAIT | SEM_UNDO) } /* decrement sem#0 by 1 (sets it to 0) */
>  };
>  
>  /*
>   * sem_lock() - Locks the semaphore for crit-sec updation, and unlocks it later
>   */
> -void sem_lock(int id)
> +static void sem_lock(int id)
>  {
> -	/* Checking the semlock and simulating as if the crit-sec is updated */
> -	if (semop(id, &semop_lock[0], 2) < 0) {
> -		perror("sem lock error");
> -		tst_brkm(TBROK, NULL, "semop failed");
> -	}
> -	tst_resm(TINFO, "Sem1: File locked, Critical section is updated...");
> +	SAFE_SEMOP(id, &semop_lock[0], 2);
> +
> +	tst_res(TINFO, "semaphore1: File locked, Critical section is updated...");
> +
>  	sleep(2);
> -	if (semop(id, &semop_unlock[0], 1) < 0) {
> -		perror("sem unlock error");
> -		tst_brkm(TBROK, NULL, "semop failed");
> -	}
> +
> +	SAFE_SEMOP(id, &semop_unlock[0], 1);
>  }
>  
>  /*
>   * check_sem1 -  does not read -- it writes to check_sem2() when it's done.
>   */
> -int check_sem1(void *vtest)
> +static int check_sem1(LTP_ATTRIBUTE_UNUSED void *vtest)
>  {
> -	int id1;
> -
> -	(void) vtest;
> -
> -	close(p1[0]);
> -	/* 1. Create (or fetch if existing) the binary semaphore */
> -	id1 = semget(MY_KEY, 1, IPC_CREAT | IPC_EXCL | 0666);
> -	if (id1 == -1) {
> -		perror("Semaphore create");
> -		if (errno != EEXIST) {
> -			perror("semget failure");
> -			tst_brkm(TBROK, NULL, "semget failure");
> -		}
> -		id1 = semget(MY_KEY, 1, 0);
> -		if (id1 == -1) {
> -			perror("Semaphore create");
> -			tst_brkm(TBROK, NULL, "semget failure");
> -		}
> +	TEST(semget(MY_KEY, 1, IPC_CREAT | IPC_EXCL | 0666));
> +	if (TST_RET < 0) {
> +		tst_res(TINFO, "semget failure. Checking existing semaphore");
> +
> +		if (TST_ERR != EEXIST)
> +			tst_brk(TBROK | TRERRNO, "Semaphore creation failed");
> +
> +		SAFE_SEMGET(MY_KEY, 1, 0);
>  	}
>  
> -	write(p1[1], "go", 3);
> -	tst_resm(TINFO, "Cont1: Able to create semaphore");
> -	tst_exit();
> +	tst_res(TINFO, "container1: Able to create semaphore");
> +
> +	return 0;
>  }
>  
>  /*
>   * check_sem2() reads from check_sem1() and writes to main() when it's done.
>   */
> -
> -int check_sem2(void *vtest)
> +static int check_sem2(LTP_ATTRIBUTE_UNUSED void *vtest)
>  {
> -	char buf[3];
> -	int id2;
> -
> -	(void) vtest;
> +	int id;
>  
> -	close(p1[1]);
> -	close(p2[0]);
> -	read(p1[0], buf, 3);
> +	id = semget(MY_KEY, 1, 0);
> +	if (id >= 0) {
> +		sem_lock(id);

I wonder why we even call the sem_lock() here, it does not add any
value to the test and only slows it down for two seconds for no reason
in the case of -m none.


Looking at the code the whole test looks strange and does not make much
sense.

Looking at the check_sem1() I guess that it's supposed to create a
semaphore in one namespace, while the check_sem2() is trying to check if
that leaks into the second namespace. But without the checkpoint
synchronization the order is not guaranteed at all.

I guess that this should really be rewritten so that:

* check_sem1() creates the semaphore, then calls CHECKPOINT_WAKE()

* check_sem2() does CHEKPOINT_WAIT() then check if the semaphore does
  exists

That is the very basic test we should do.

On the top of that we can make the check_sem1() to also lock the
semaphore between the call to wake the other process. And the other
process check_sem2() can attempt to lock it as well with IPC_NOWAIT. If
that fails the reference to the semaphore somehow leaked even if the
namespaces are isolated.
diff mbox series

Patch

diff --git a/testcases/kernel/containers/sysvipc/semtest_2ns.c b/testcases/kernel/containers/sysvipc/semtest_2ns.c
index c3483b675..c0c6f445e 100644
--- a/testcases/kernel/containers/sysvipc/semtest_2ns.c
+++ b/testcases/kernel/containers/sysvipc/semtest_2ns.c
@@ -1,230 +1,149 @@ 
-/* *************************************************************************
-* Copyright (c) International Business Machines Corp., 2009
-* This program is free software; you can redistribute it and/or modify
-* it under the terms of the GNU General Public License as published by
-* the Free Software Foundation; either version 2 of the License, or
-* (at your option) any later version.
-*
-* This program is distributed in the hope that it will be useful,
-* but WITHOUT ANY WARRANTY; without even the implied warranty of
-* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
-* the GNU General Public License for more details.
-* You should have received a copy of the GNU General Public License
-* along with this program; if not, write to the Free Software
-* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
-*
-* Author: Veerendra C <vechandr@in.ibm.com>
-*
-* Test Assertion:
-* This testcase verifies the semaphore isoloation in 2 diff containers.
-* It tries to create/access a semaphore created with the same KEY.
-*
-* Description:
-* Create 2 'containers' with the below flag value
-*   Flag = clone, clone(CLONE_NEWIPC), or unshare(CLONE_NEWIPC)
-* In Cont1, create semaphore with key 124326L
-* In Cont2, try to access the semaphore created in Cont1.
-* PASS :
-*		If flag = None and the semaphore is accessible in Cont2.
-*		If flag = unshare/clone and the semaphore is not accessible in Cont2.
-*		If semaphore is not accessible in Cont2, creates new semaphore with
-*		the same key to double check isloation in IPCNS.
-*
-* FAIL :
-*		If flag = none and the semaphore is not accessible.
-*		If flag = unshare/clone and semaphore is accessible in Cont2.
-*		If the new semaphore creation Fails.
-***************************************************************************/
-
-#define _GNU_SOURCE 1
-#include <stdio.h>
-#include <stdlib.h>
-#include <unistd.h>
-#include <string.h>
-#include <sys/ipc.h>
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (c) International Business Machines Corp., 2009
+ *				Veerendra C <vechandr@in.ibm.com>
+ * Copyright (C) 2022 SUSE LLC Andrea Cervesato <andrea.cervesato@suse.com>
+ */
+
+/*\
+ * [Description]
+ *
+ * Test SysV IPC semaphore usage between namespaces.
+ *
+ * [Algorithm]
+ *
+ * Create 2 'containers'
+ * In container1 create semaphore with a specific key
+ * In container2 try to access the semaphore created in container1
+ *
+ * Test is PASS if flag = none and the semaphore is accessible in container2 or
+ * if flag = unshare/clone and the semaphore is not accessible in container2.
+ * If semaphore is not accessible in container2, creates new semaphore with the
+ * same key to double check isloation in IPCNS.
+ *
+ * Test is FAIL if flag = none and the semaphore is not accessible, if
+ * flag = unshare/clone and semaphore is accessible in container2 or if the new
+ * semaphore creation Fails.
+ */
+
+#define _GNU_SOURCE
+
+#include <sys/wait.h>
+#include <sys/msg.h>
+#include <sys/types.h>
 #include <sys/sem.h>
-#include <libclone.h>
-#include "test.h"
-#include "ipcns_helper.h"
-
-#define MY_KEY     124326L
-#define UNSHARESTR "unshare"
-#define CLONESTR   "clone"
-#define NONESTR    "none"
-
-char *TCID = "semtest_2ns";
-int TST_TOTAL = 1;
-int p1[2];
-int p2[2];
+#include "tst_safe_sysv_ipc.h"
+#include "tst_test.h"
+#include "common.h"
+
+#define MY_KEY 124326L
+
+static char *str_op = "clone";
+static int use_clone;
+
 static struct sembuf semop_lock[2] = {
 	/* sem_num, sem_op, flag */
-	{0, 0, 0},		/* wait for sem#0 to become 0 */
-	{0, 1, SEM_UNDO}	/* then increment sem#0 by 1 */
+	{ 0, 0, 0 }, /* wait for sem#0 to become 0 */
+	{ 0, 1, SEM_UNDO } /* then increment sem#0 by 1 */
 };
 
 static struct sembuf semop_unlock[1] = {
 	/* sem_num, sem_op, flag */
-	{0, -1, (IPC_NOWAIT | SEM_UNDO)}	/* decrement sem#0 by 1 (sets it to 0) */
+	{ 0, -1, (IPC_NOWAIT | SEM_UNDO) } /* decrement sem#0 by 1 (sets it to 0) */
 };
 
 /*
  * sem_lock() - Locks the semaphore for crit-sec updation, and unlocks it later
  */
-void sem_lock(int id)
+static void sem_lock(int id)
 {
-	/* Checking the semlock and simulating as if the crit-sec is updated */
-	if (semop(id, &semop_lock[0], 2) < 0) {
-		perror("sem lock error");
-		tst_brkm(TBROK, NULL, "semop failed");
-	}
-	tst_resm(TINFO, "Sem1: File locked, Critical section is updated...");
+	SAFE_SEMOP(id, &semop_lock[0], 2);
+
+	tst_res(TINFO, "semaphore1: File locked, Critical section is updated...");
+
 	sleep(2);
-	if (semop(id, &semop_unlock[0], 1) < 0) {
-		perror("sem unlock error");
-		tst_brkm(TBROK, NULL, "semop failed");
-	}
+
+	SAFE_SEMOP(id, &semop_unlock[0], 1);
 }
 
 /*
  * check_sem1 -  does not read -- it writes to check_sem2() when it's done.
  */
-int check_sem1(void *vtest)
+static int check_sem1(LTP_ATTRIBUTE_UNUSED void *vtest)
 {
-	int id1;
-
-	(void) vtest;
-
-	close(p1[0]);
-	/* 1. Create (or fetch if existing) the binary semaphore */
-	id1 = semget(MY_KEY, 1, IPC_CREAT | IPC_EXCL | 0666);
-	if (id1 == -1) {
-		perror("Semaphore create");
-		if (errno != EEXIST) {
-			perror("semget failure");
-			tst_brkm(TBROK, NULL, "semget failure");
-		}
-		id1 = semget(MY_KEY, 1, 0);
-		if (id1 == -1) {
-			perror("Semaphore create");
-			tst_brkm(TBROK, NULL, "semget failure");
-		}
+	TEST(semget(MY_KEY, 1, IPC_CREAT | IPC_EXCL | 0666));
+	if (TST_RET < 0) {
+		tst_res(TINFO, "semget failure. Checking existing semaphore");
+
+		if (TST_ERR != EEXIST)
+			tst_brk(TBROK | TRERRNO, "Semaphore creation failed");
+
+		SAFE_SEMGET(MY_KEY, 1, 0);
 	}
 
-	write(p1[1], "go", 3);
-	tst_resm(TINFO, "Cont1: Able to create semaphore");
-	tst_exit();
+	tst_res(TINFO, "container1: Able to create semaphore");
+
+	return 0;
 }
 
 /*
  * check_sem2() reads from check_sem1() and writes to main() when it's done.
  */
-
-int check_sem2(void *vtest)
+static int check_sem2(LTP_ATTRIBUTE_UNUSED void *vtest)
 {
-	char buf[3];
-	int id2;
-
-	(void) vtest;
+	int id;
 
-	close(p1[1]);
-	close(p2[0]);
-	read(p1[0], buf, 3);
+	id = semget(MY_KEY, 1, 0);
+	if (id >= 0) {
+		sem_lock(id);
 
-	id2 = semget(MY_KEY, 1, 0);
-	if (id2 != -1) {
-		sem_lock(id2);
-		write(p2[1], "exists", 7);
+		if (use_clone == T_NONE)
+			tst_res(TPASS, "Plain cloned process able to access the semaphore created");
+		else
+			tst_res(TFAIL, "%s : In namespace2 found the semaphore created in Namespace1", str_op);
 	} else {
 		/* Trying to create a new semaphore, if semaphore is not existing */
-		id2 = semget(MY_KEY, 1, IPC_CREAT | IPC_EXCL | 0666);
-		if (id2 == -1) {
-			perror("Semaphore create");
-			if (errno != EEXIST) {
-				perror("semget failure");
-				tst_resm(TBROK, "semget failure");
-			}
-		} else
-			tst_resm(TINFO,
-				 "Cont2: Able to create semaphore with sameKey");
-		/* Passing the pipe Not-found mesg */
-		write(p2[1], "notfnd", 7);
+		TEST(semget(MY_KEY, 1, IPC_CREAT | IPC_EXCL | 0666));
+		if (TST_RET < 0) {
+			if (TST_ERR != EEXIST)
+				tst_brk(TBROK | TERRNO, "semget error");
+		} else {
+			tst_res(TINFO, "container2: Able to create semaphore with sameKey");
+		}
+
+		if (use_clone == T_NONE)
+			tst_res(TFAIL, "Plain cloned process didn't find semaphore");
+		else
+			tst_res(TPASS, "%s : In namespace2 unable to access the semaphore created in namespace1", str_op);
 	}
 
-	tst_exit();
+	id = SAFE_SEMGET(MY_KEY, 1, 0);
+	SAFE_SEMCTL(id, IPC_RMID, 0);
+
+	return 0;
 }
 
-static void setup(void)
+static void run(void)
 {
-	tst_require_root();
-	check_newipc();
+	clone_unshare_test(use_clone, CLONE_NEWIPC, check_sem1, NULL);
+	clone_unshare_test(use_clone, CLONE_NEWIPC, check_sem2, NULL);
 }
 
-int main(int argc, char *argv[])
+static void setup(void)
 {
-	int ret, id, use_clone = T_NONE;
-	char *tsttype = NONESTR;
-	char buf[7];
-
-	setup();
-
-	if (argc != 2) {
-		tst_resm(TINFO, "Usage: %s <clone| unshare| none>", argv[0]);
-		tst_resm(TINFO, " where clone, unshare, or fork specifies"
-			 " unshare method.");
-		tst_exit();
-	}
-
-	/* Using PIPE's to sync between container and Parent */
-	if (pipe(p1) == -1) {
-		perror("pipe1");
-		tst_exit();
-	}
-	if (pipe(p2) == -1) {
-		perror("pipe2");
-		tst_exit();
-	}
+	use_clone = get_clone_unshare_enum(str_op);
 
-	if (strcmp(argv[1], "clone") == 0) {
-		use_clone = T_CLONE;
-		tsttype = CLONESTR;
-	} else if (strcmp(argv[1], "unshare") == 0) {
-		use_clone = T_UNSHARE;
-		tsttype = UNSHARESTR;
-	}
-
-	tst_resm(TINFO, "Semaphore Namespaces Test : %s", tsttype);
-
-	/* Create 2 containers */
-	ret = do_clone_unshare_test(use_clone, CLONE_NEWIPC, check_sem1, NULL);
-	if (ret < 0) {
-		tst_brkm(TFAIL, NULL, "clone/unshare failed");
-	}
-
-	ret = do_clone_unshare_test(use_clone, CLONE_NEWIPC, check_sem2, NULL);
-	if (ret < 0) {
-		tst_brkm(TFAIL, NULL, "clone/unshare failed");
-	}
-	close(p2[1]);
-	read(p2[0], buf, 7);
-
-	if (strcmp(buf, "exists") == 0)
-		if (use_clone == T_NONE)
-			tst_resm(TPASS,
-				 "Plain cloned process able to access the semaphore "
-				 "created");
-		else
-			tst_resm(TFAIL,
-				 "%s : In namespace2 found the semaphore "
-				 "created in Namespace1", tsttype);
-	else if (use_clone == T_NONE)
-		tst_resm(TFAIL, "Plain cloned process didn't find semaphore");
-	else
-		tst_resm(TPASS,
-			 "%s : In namespace2 unable to access the semaphore "
-			 "created in Namespace1", tsttype);
-
-	/* Delete the semaphore */
-	id = semget(MY_KEY, 1, 0);
-	semctl(id, IPC_RMID, 0);
-	tst_exit();
+	if (use_clone != T_NONE)
+		check_newipc();
 }
+
+static struct tst_test test = {
+	.test_all = run,
+	.setup = setup,
+	.needs_root = 1,
+	.forks_child = 1,
+	.options = (struct tst_option[]) {
+		{ "m:", &str_op, "Test execution mode <clone|unshare|none>" },
+		{},
+	},
+};