diff mbox series

[v4] Refactor fork14 using new LTP API

Message ID 20240313124542.13636-1-andrea.cervesato@suse.de
State Superseded
Headers show
Series [v4] Refactor fork14 using new LTP API | expand

Commit Message

Andrea Cervesato March 13, 2024, 12:45 p.m. UTC 
From: Andrea Cervesato <andrea.cervesato@suse.com>

Signed-off-by: Andrea Cervesato <andrea.cervesato@suse.com>
---
Reverted SAFE_MMAP to mmap
Added kernel tags

 testcases/kernel/syscalls/fork/fork14.c | 208 +++++++++++-------------
 1 file changed, 96 insertions(+), 112 deletions(-)

Comments

Petr Vorel March 22, 2024, 6:42 a.m. UTC | #1 
Hi Andrea,

generally LGTM.
With using .skip_in_compat and SPDX GPL-2.0-only:

Reviewed-by: Petr Vorel <pvorel@suse.cz>

Minor notes below.

> ---
> Reverted SAFE_MMAP to mmap
> Added kernel tags
+1

>  testcases/kernel/syscalls/fork/fork14.c | 208 +++++++++++-------------
...
> +// SPDX-License-Identifier: GPL-2.0-or-later
> +/*
>   * Copyright (C) 2014  Red Hat, Inc.
> + * Copyright (C) 2023 SUSE LLC Andrea Cervesato <andrea.cervesato@suse.com>
> + */
> +
> +/*\
> + * [Description]
>   *
> - * This program is free software; you can redistribute it and/or
> - * modify it under the terms of version 2 of the GNU General Public
> - * License as published by the Free Software Foundation.

This is GPL-2.0-only.
> - *
> - * This program is distributed in the hope that it would be useful,
> - * but WITHOUT ANY WARRANTY; without even the implied warranty of
> - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
> - *
> - * Further, this software is distributed without any warranty that it
> - * is free of the rightful claim of any third person regarding
> - * infringement or the like.  Any license provided herein, whether
> - * implied or otherwise, applies only to this software file.  Patent
> - * licenses, if any, provided herein do not apply to combinations of
> - * this program with other software, or any other product whatsoever.
> - *
> - * You should have received a copy of the GNU General Public License
> - * along with this program; if not, write the Free Software
> - * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
> - * 02110-1301, USA.
> - *
> - * This test is a reporducer for this patch:
> - *              https://lkml.org/lkml/2012/4/24/328
> + * This test is a reporducer for this patch: https://lkml.org/lkml/2012/4/24/328
very nit: I would trust lore more, thus I would use

https://lore.kernel.org/lkml/1335289853-2923-1-git-send-email-siddhesh.poyarekar@gmail.com/

>   * Since vma length in dup_mmap is calculated and stored in a unsigned
>   * int, it will overflow when length of mmaped memory > 16 TB. When
> - * overflow occur, fork will  incorrectly succeed. The patch above
> - * fixed it.
> - ********************************************************************/
> + * overflow occur, fork will incorrectly succeed. The patch above fixed it.
s/occur/occurs/

> + */

> -#include <sys/mman.h>
> -#include <sys/wait.h>
> -#include <stdio.h>
> -#include <unistd.h>
> -#include "test.h"
> -#include "safe_macros.h"
> -#include "lapi/abisize.h"
> +#include "tst_test.h"

> -char *TCID = "fork14";
> -int TST_TOTAL = 1;
> +#ifndef TST_ABI32

We can use .skip_in_compat = 1, flag instead.

> -#define GB		(1024 * 1024 * 1024L)
> +#include <stdlib.h>
> +#include <sys/wait.h>

> -/* set mmap threshold to 16TB */
>  #define LARGE		(16 * 1024)
>  #define EXTENT		(16 * 1024 + 10)

> -static char **pointer_vec;
> +static char **memvec;

> -static void setup(void);
> -static void cleanup(void);
> -static int  fork_test(void);
> -
> -int main(int ac, char **av)
> +static void run(void)
>  {
> -	int lc, reproduced;
> +	int i, j, ret;
> +	pid_t pid;
> +	void *mem;
> +	int prev_failed = 0;
> +	int passed = 1;
> +	int failures = 0;

> +	for (i = 0; i < EXTENT; i++) {
I wonder if the code would not be slightly more readable if the content of the
loop was in the separate function. Probably not, feel free to ignore.

> +		mem = mmap(NULL, 1 * TST_GB,
> +			PROT_READ | PROT_WRITE,
> +			MAP_PRIVATE | MAP_ANONYMOUS,
> +			0, 0);
...
> +		if (mem == MAP_FAILED) {
> +			failures++;
...
> +			if (failures > 10) {
> +				tst_brk(TCONF, "mmap() fails too many "
> +					"times, so it's almost impossible to "
> +					"get a vm_area_struct sized 16TB.");
> +			}

> -static void cleanup(void)
> -{
> -	free(pointer_vec);
> -}
> +			continue;
> +		}


> -		switch (tst_fork()) {
> -		case -1:
> -			prev_failed = 1;
> -		break;
> -		case 0:
> +		if (!pid)
>  			exit(0);
> -		default:
> -			SAFE_WAITPID(cleanup, -1, NULL, 0);

> -			if (prev_failed > 0 && i >= LARGE) {
> -				tst_resm(TFAIL, "Fork succeeds incorrectly");
> -				reproduced = 1;
> -				goto clear_memory_map;
> -			}
> +		ret = waitpid(pid, NULL, 0);
Why not SAFE_WAITPID() as it was originally?

> +		if (ret == -1 && errno != ECHILD)
> +			tst_brk(TBROK | TERRNO, "waitpid() error");
> +
> +		if (prev_failed && i >= LARGE) {
> +			passed = 0;
> +			break;
>  		}
> +
> +		prev_failed = 0;
> +
> +		tst_res(TINFO, "fork() passed at %d attempt", i);
> +	}
> +
> +	for (j = 0; j < i; j++) {
> +		if (memvec[j])
> +			SAFE_MUNMAP(memvec[j], 1 * TST_GB);
>  	}

> -clear_memory_map:
> -	for (j = 0; j < cnt; j++) {
> -		if (pointer_vec[j])
> -			SAFE_MUNMAP(cleanup, pointer_vec[j], 1 * GB);
> +	if (passed)
> +		tst_res(TPASS, "fork() failed as expected");
> +	else
> +		tst_res(TFAIL, "fork() succeeded incorrectly");
> +}
> +
> +static void setup(void)
> +{
> +	memvec = SAFE_MALLOC(EXTENT * sizeof(char *));
> +	memset(memvec, 0, EXTENT);
> +}
> +
> +static void cleanup(void)
> +{
> +	for (long i = 0; i < EXTENT; i++) {
> +		if (memvec && memvec[i])
> +			SAFE_MUNMAP(memvec[i], 1 * TST_GB);
>  	}

> -	return reproduced;
> +	if (memvec)
> +		free(memvec);
>  }
> +
> +static struct tst_test test = {
> +	.test_all = run,
> +	.setup = setup,
> +	.cleanup = cleanup,
> +	.forks_child = 1,
> +	.tags = (const struct tst_tag[]) {
> +		{"linux-git", "7edc8b0ac16cbaed7cb4ea4c6b95ce98d2997e84"},
nit: we usually use shorter hash 7edc8b0ac16c (as used in Fixes: in git
commits).

> +		{}
> +	}
> +};
> +
> +#else /* TST_ABI32 */
> +	TST_TEST_TCONF("Test doesn't supports 32bits architecture");
s/supports/support/

But we can use .skip_in_compat = 1, flag instead.

Kind regards,
Petr

> +#endif
Andrea Cervesato March 22, 2024, 8:59 a.m. UTC | #2 
Hi,

On 3/22/24 07:42, Petr Vorel wrote:
> Hi Andrea,
>
> generally LGTM.
> With using .skip_in_compat and SPDX GPL-2.0-only:
Totally forgot the license..
>
> Reviewed-by: Petr Vorel <pvorel@suse.cz>
>
> Minor notes below.
>
>> ---
>> Reverted SAFE_MMAP to mmap
>> Added kernel tags
> +1
>
>>   testcases/kernel/syscalls/fork/fork14.c | 208 +++++++++++-------------
> ...
>> +// SPDX-License-Identifier: GPL-2.0-or-later
>> +/*
>>    * Copyright (C) 2014  Red Hat, Inc.
>> + * Copyright (C) 2023 SUSE LLC Andrea Cervesato <andrea.cervesato@suse.com>
>> + */
>> +
>> +/*\
>> + * [Description]
>>    *
>> - * This program is free software; you can redistribute it and/or
>> - * modify it under the terms of version 2 of the GNU General Public
>> - * License as published by the Free Software Foundation.
> This is GPL-2.0-only.
>> - *
>> - * This program is distributed in the hope that it would be useful,
>> - * but WITHOUT ANY WARRANTY; without even the implied warranty of
>> - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
>> - *
>> - * Further, this software is distributed without any warranty that it
>> - * is free of the rightful claim of any third person regarding
>> - * infringement or the like.  Any license provided herein, whether
>> - * implied or otherwise, applies only to this software file.  Patent
>> - * licenses, if any, provided herein do not apply to combinations of
>> - * this program with other software, or any other product whatsoever.
>> - *
>> - * You should have received a copy of the GNU General Public License
>> - * along with this program; if not, write the Free Software
>> - * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
>> - * 02110-1301, USA.
>> - *
>> - * This test is a reporducer for this patch:
>> - *              https://lkml.org/lkml/2012/4/24/328
>> + * This test is a reporducer for this patch: https://lkml.org/lkml/2012/4/24/328
> very nit: I would trust lore more, thus I would use
>
> https://lore.kernel.org/lkml/1335289853-2923-1-git-send-email-siddhesh.poyarekar@gmail.com/
>
>>    * Since vma length in dup_mmap is calculated and stored in a unsigned
>>    * int, it will overflow when length of mmaped memory > 16 TB. When
>> - * overflow occur, fork will  incorrectly succeed. The patch above
>> - * fixed it.
>> - ********************************************************************/
>> + * overflow occur, fork will incorrectly succeed. The patch above fixed it.
> s/occur/occurs/
>
>> + */
>> -#include <sys/mman.h>
>> -#include <sys/wait.h>
>> -#include <stdio.h>
>> -#include <unistd.h>
>> -#include "test.h"
>> -#include "safe_macros.h"
>> -#include "lapi/abisize.h"
>> +#include "tst_test.h"
>> -char *TCID = "fork14";
>> -int TST_TOTAL = 1;
>> +#ifndef TST_ABI32
> We can use .skip_in_compat = 1, flag instead.
>
>> -#define GB		(1024 * 1024 * 1024L)
>> +#include <stdlib.h>
>> +#include <sys/wait.h>
>> -/* set mmap threshold to 16TB */
>>   #define LARGE		(16 * 1024)
>>   #define EXTENT		(16 * 1024 + 10)
>> -static char **pointer_vec;
>> +static char **memvec;
>> -static void setup(void);
>> -static void cleanup(void);
>> -static int  fork_test(void);
>> -
>> -int main(int ac, char **av)
>> +static void run(void)
>>   {
>> -	int lc, reproduced;
>> +	int i, j, ret;
>> +	pid_t pid;
>> +	void *mem;
>> +	int prev_failed = 0;
>> +	int passed = 1;
>> +	int failures = 0;
>> +	for (i = 0; i < EXTENT; i++) {
> I wonder if the code would not be slightly more readable if the content of the
> loop was in the separate function. Probably not, feel free to ignore.
>
>> +		mem = mmap(NULL, 1 * TST_GB,
>> +			PROT_READ | PROT_WRITE,
>> +			MAP_PRIVATE | MAP_ANONYMOUS,
>> +			0, 0);
> ...
>> +		if (mem == MAP_FAILED) {
>> +			failures++;
> ...
>> +			if (failures > 10) {
>> +				tst_brk(TCONF, "mmap() fails too many "
>> +					"times, so it's almost impossible to "
>> +					"get a vm_area_struct sized 16TB.");
>> +			}
>> -static void cleanup(void)
>> -{
>> -	free(pointer_vec);
>> -}
>> +			continue;
>> +		}
>
>> -		switch (tst_fork()) {
>> -		case -1:
>> -			prev_failed = 1;
>> -		break;
>> -		case 0:
>> +		if (!pid)
>>   			exit(0);
>> -		default:
>> -			SAFE_WAITPID(cleanup, -1, NULL, 0);
>> -			if (prev_failed > 0 && i >= LARGE) {
>> -				tst_resm(TFAIL, "Fork succeeds incorrectly");
>> -				reproduced = 1;
>> -				goto clear_memory_map;
>> -			}
>> +		ret = waitpid(pid, NULL, 0);
> Why not SAFE_WAITPID() as it was originally?
Was discussed with Cyril in the previous review. It's because we don't 
want it to fail only once.
>
>> +		if (ret == -1 && errno != ECHILD)
>> +			tst_brk(TBROK | TERRNO, "waitpid() error");
>> +
>> +		if (prev_failed && i >= LARGE) {
>> +			passed = 0;
>> +			break;
>>   		}
>> +
>> +		prev_failed = 0;
>> +
>> +		tst_res(TINFO, "fork() passed at %d attempt", i);
>> +	}
>> +
>> +	for (j = 0; j < i; j++) {
>> +		if (memvec[j])
>> +			SAFE_MUNMAP(memvec[j], 1 * TST_GB);
>>   	}
>> -clear_memory_map:
>> -	for (j = 0; j < cnt; j++) {
>> -		if (pointer_vec[j])
>> -			SAFE_MUNMAP(cleanup, pointer_vec[j], 1 * GB);
>> +	if (passed)
>> +		tst_res(TPASS, "fork() failed as expected");
>> +	else
>> +		tst_res(TFAIL, "fork() succeeded incorrectly");
>> +}
>> +
>> +static void setup(void)
>> +{
>> +	memvec = SAFE_MALLOC(EXTENT * sizeof(char *));
>> +	memset(memvec, 0, EXTENT);
>> +}
>> +
>> +static void cleanup(void)
>> +{
>> +	for (long i = 0; i < EXTENT; i++) {
>> +		if (memvec && memvec[i])
>> +			SAFE_MUNMAP(memvec[i], 1 * TST_GB);
>>   	}
>> -	return reproduced;
>> +	if (memvec)
>> +		free(memvec);
>>   }
>> +
>> +static struct tst_test test = {
>> +	.test_all = run,
>> +	.setup = setup,
>> +	.cleanup = cleanup,
>> +	.forks_child = 1,
>> +	.tags = (const struct tst_tag[]) {
>> +		{"linux-git", "7edc8b0ac16cbaed7cb4ea4c6b95ce98d2997e84"},
> nit: we usually use shorter hash 7edc8b0ac16c (as used in Fixes: in git
> commits).
>
>> +		{}
>> +	}
>> +};
>> +
>> +#else /* TST_ABI32 */
>> +	TST_TEST_TCONF("Test doesn't supports 32bits architecture");
> s/supports/support/
>
> But we can use .skip_in_compat = 1, flag instead.
>
> Kind regards,
> Petr
>
>> +#endif

Andrea
Petr Vorel March 22, 2024, 9:36 a.m. UTC | #3 
Hi Andrea,

> > generally LGTM.
> > With using .skip_in_compat and SPDX GPL-2.0-only:
> Totally forgot the license..

Thanks for sending v5.

...
> > > -		default:
> > > -			SAFE_WAITPID(cleanup, -1, NULL, 0);
> > > -			if (prev_failed > 0 && i >= LARGE) {
> > > -				tst_resm(TFAIL, "Fork succeeds incorrectly");
> > > -				reproduced = 1;
> > > -				goto clear_memory_map;
> > > -			}
> > > +		ret = waitpid(pid, NULL, 0);
> > Why not SAFE_WAITPID() as it was originally?
> Was discussed with Cyril in the previous review. It's because we don't want
> it to fail only once.

Ah, I'm sorry, I overlooked it.

Kind regards,
Petr
diff mbox series

Patch

diff --git a/testcases/kernel/syscalls/fork/fork14.c b/testcases/kernel/syscalls/fork/fork14.c
index 93af2ebac..c5a5a96be 100644
--- a/testcases/kernel/syscalls/fork/fork14.c
+++ b/testcases/kernel/syscalls/fork/fork14.c
@@ -1,143 +1,127 @@ 
-/*********************************************************************
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
  * Copyright (C) 2014  Red Hat, Inc.
+ * Copyright (C) 2023 SUSE LLC Andrea Cervesato <andrea.cervesato@suse.com>
+ */
+
+/*\
+ * [Description]
  *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of version 2 of the GNU General Public
- * License as published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it would be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
- *
- * Further, this software is distributed without any warranty that it
- * is free of the rightful claim of any third person regarding
- * infringement or the like.  Any license provided herein, whether
- * implied or otherwise, applies only to this software file.  Patent
- * licenses, if any, provided herein do not apply to combinations of
- * this program with other software, or any other product whatsoever.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
- * 02110-1301, USA.
- *
- * This test is a reporducer for this patch:
- *              https://lkml.org/lkml/2012/4/24/328
+ * This test is a reporducer for this patch: https://lkml.org/lkml/2012/4/24/328
  * Since vma length in dup_mmap is calculated and stored in a unsigned
  * int, it will overflow when length of mmaped memory > 16 TB. When
- * overflow occur, fork will  incorrectly succeed. The patch above
- * fixed it.
- ********************************************************************/
+ * overflow occur, fork will incorrectly succeed. The patch above fixed it.
+ */
 
-#include <sys/mman.h>
-#include <sys/wait.h>
-#include <stdio.h>
-#include <unistd.h>
-#include "test.h"
-#include "safe_macros.h"
-#include "lapi/abisize.h"
+#include "tst_test.h"
 
-char *TCID = "fork14";
-int TST_TOTAL = 1;
+#ifndef TST_ABI32
 
-#define GB		(1024 * 1024 * 1024L)
+#include <stdlib.h>
+#include <sys/wait.h>
 
-/* set mmap threshold to 16TB */
 #define LARGE		(16 * 1024)
 #define EXTENT		(16 * 1024 + 10)
 
-static char **pointer_vec;
+static char **memvec;
 
-static void setup(void);
-static void cleanup(void);
-static int  fork_test(void);
-
-int main(int ac, char **av)
+static void run(void)
 {
-	int lc, reproduced;
+	int i, j, ret;
+	pid_t pid;
+	void *mem;
+	int prev_failed = 0;
+	int passed = 1;
+	int failures = 0;
 
-	tst_parse_opts(ac, av, NULL, NULL);
-/*
- * Tested on ppc64/x86_64/i386/s390x. And only 64bit has this issue.
- * Since a 32bit program can't mmap so many memory.
- */
-#ifdef TST_ABI32
-	tst_brkm(TCONF, NULL, "This test is only for 64bit.");
-#endif
-	setup();
-	for (lc = 0; TEST_LOOPING(lc); lc++) {
-		tst_count = 0;
+	for (i = 0; i < EXTENT; i++) {
+		mem = mmap(NULL, 1 * TST_GB,
+			PROT_READ | PROT_WRITE,
+			MAP_PRIVATE | MAP_ANONYMOUS,
+			0, 0);
 
-		reproduced = fork_test();
-		if (reproduced == 0)
-			tst_resm(TPASS, "fork failed as expected.");
-	}
-	cleanup();
-	tst_exit();
-}
+		if (mem == MAP_FAILED) {
+			failures++;
 
-static void setup(void)
-{
-	tst_sig(FORK, DEF_HANDLER, cleanup);
-	TEST_PAUSE;
+			tst_res(TINFO, "mmap() failed");
 
-	pointer_vec = SAFE_MALLOC(cleanup, EXTENT * sizeof(char *));
-}
+			if (failures > 10) {
+				tst_brk(TCONF, "mmap() fails too many "
+					"times, so it's almost impossible to "
+					"get a vm_area_struct sized 16TB.");
+			}
 
-static void cleanup(void)
-{
-	free(pointer_vec);
-}
+			continue;
+		}
 
-static int fork_test(void)
-{
-	int i, j, prev_failed = 0, fails = 0, cnt = 0;
-	int reproduced = 0;
-	void *addr;
+		memvec[i] = mem;
 
-	for (i = 0; i < EXTENT; i++) {
-		addr = mmap(NULL, 1 * GB, PROT_READ | PROT_WRITE,
-			    MAP_PRIVATE | MAP_ANONYMOUS, 0, 0);
-		if (addr == MAP_FAILED) {
-			pointer_vec[i] = NULL;
-			fails++;
-			/*
-			 * EXTENT is "16*1024+10", if fails count exceeds 10,
-			 * we are almost impossible to get an vm_area_struct
-			 * sized 16TB
+		pid = fork();
+
+		if (pid == -1) {
+			/* keep track of the failed fork() and verify that next one
+			 * is failing as well.
 			 */
-			if (fails == 11) {
-				tst_brkm(TCONF, cleanup, "mmap() fails too many"
-					 "times, so we are almost impossible to"
-					 " get an vm_area_struct sized 16TB.");
-			}
-		} else {
-			pointer_vec[i] = addr;
+			prev_failed = 1;
+			continue;
 		}
-		cnt++;
 
-		switch (tst_fork()) {
-		case -1:
-			prev_failed = 1;
-		break;
-		case 0:
+		if (!pid)
 			exit(0);
-		default:
-			SAFE_WAITPID(cleanup, -1, NULL, 0);
 
-			if (prev_failed > 0 && i >= LARGE) {
-				tst_resm(TFAIL, "Fork succeeds incorrectly");
-				reproduced = 1;
-				goto clear_memory_map;
-			}
+		ret = waitpid(pid, NULL, 0);
+		if (ret == -1 && errno != ECHILD)
+			tst_brk(TBROK | TERRNO, "waitpid() error");
+
+		if (prev_failed && i >= LARGE) {
+			passed = 0;
+			break;
 		}
+
+		prev_failed = 0;
+
+		tst_res(TINFO, "fork() passed at %d attempt", i);
+	}
+
+	for (j = 0; j < i; j++) {
+		if (memvec[j])
+			SAFE_MUNMAP(memvec[j], 1 * TST_GB);
 	}
 
-clear_memory_map:
-	for (j = 0; j < cnt; j++) {
-		if (pointer_vec[j])
-			SAFE_MUNMAP(cleanup, pointer_vec[j], 1 * GB);
+	if (passed)
+		tst_res(TPASS, "fork() failed as expected");
+	else
+		tst_res(TFAIL, "fork() succeeded incorrectly");
+}
+
+static void setup(void)
+{
+	memvec = SAFE_MALLOC(EXTENT * sizeof(char *));
+	memset(memvec, 0, EXTENT);
+}
+
+static void cleanup(void)
+{
+	for (long i = 0; i < EXTENT; i++) {
+		if (memvec && memvec[i])
+			SAFE_MUNMAP(memvec[i], 1 * TST_GB);
 	}
 
-	return reproduced;
+	if (memvec)
+		free(memvec);
 }
+
+static struct tst_test test = {
+	.test_all = run,
+	.setup = setup,
+	.cleanup = cleanup,
+	.forks_child = 1,
+	.tags = (const struct tst_tag[]) {
+		{"linux-git", "7edc8b0ac16cbaed7cb4ea4c6b95ce98d2997e84"},
+		{}
+	}
+};
+
+#else /* TST_ABI32 */
+	TST_TEST_TCONF("Test doesn't supports 32bits architecture");
+#endif