[LTP] [PATCH v2] Test : madvise('MADV_WIPEONFORK')

[Jan Stancek <jstancek@redhat.com>]

----- Original Message -----
> 
>  madvise10.c :- Present the child process with zero-filled memory in
>   this range after a fork(2).
>   Test-Case 1 : madvise with 'MADV_WIPEONFORK'
>   Test-Case 2 : madvise with 'MADV_WIPEONFORK' as size 'ZERO'
> 
>  madvise11.c:- The MADV_WIPEONFORK operation can be applied only to
>   private anonymous pages.
>   Test-Case 1 : mmap with 'MAP_SHARED | MAP_ANONYMOUS'
>   Test-Case 2 : mmap with 'MAP_PRIVATE'
> 
>  madvise12.c:- Within the child created by fork(2), the MADV_WIPEONFORK
>   setting remains in place on the specified address range.
>   Test-Case 1: 'MADV_WIPEONFORK' on Grand child
> 
>  madvise13.c:- MADV_KEEPONFORK Undo the effect of an earlier MADV_WIPEONFORK
>   Test-Case 1 : Undo 'MADV_WIPEONFORK' by 'MADV_KEEPONFORK'
> 
> * Update from v1 to v2:-
> 
>  Added EINVAL error check in madvise02.
>  Tests having common code are combined together and put into one
>   single file madvise10.c.
>  Files were added to .gitignore which was left out in the previous
>   patch file.
>  Using -1 as file descriptor for MAP_PRIVATE | MAP_ANONYMOUS page.
>  Whole mapped-memory area is compared instead of first byte.
>  Printing test_errno with TFAIL.
> 
> Signed-off-by: Subash Ganesan <subash@zilogic.com>
> Signed-off-by: Kewal Ukunde <kewal@zilogic.com>
> Acked-by: Jan Stancek <jstancek@redhat.com>

Please don't add my ack, when I didn't have a chance to review yet.
I'll try to have a look tomorrow.

Jan

> ---
>  runtest/syscalls                              |   1 +
>  testcases/kernel/syscalls/madvise/.gitignore  |   1 +
>  testcases/kernel/syscalls/madvise/madvise02.c |  12 ++
>  testcases/kernel/syscalls/madvise/madvise10.c | 184
>  ++++++++++++++++++++++++++
>  4 files changed, 198 insertions(+)
>  create mode 100644 testcases/kernel/syscalls/madvise/madvise10.c
> 
> diff --git a/runtest/syscalls b/runtest/syscalls
> index a9afecf57..9b30635c2 100644
> --- a/runtest/syscalls
> +++ b/runtest/syscalls
> @@ -773,6 +773,7 @@ madvise06 madvise06
>  madvise07 madvise07
>  madvise08 madvise08
>  madvise09 madvise09
> +madvise10 madvise10
>  
>  newuname01 newuname01
>  
> diff --git a/testcases/kernel/syscalls/madvise/.gitignore
> b/testcases/kernel/syscalls/madvise/.gitignore
> index 58bafb1b0..002d8e5d9 100644
> --- a/testcases/kernel/syscalls/madvise/.gitignore
> +++ b/testcases/kernel/syscalls/madvise/.gitignore
> @@ -5,3 +5,4 @@
>  /madvise07
>  /madvise08
>  /madvise09
> +/madvise10
> diff --git a/testcases/kernel/syscalls/madvise/madvise02.c
> b/testcases/kernel/syscalls/madvise/madvise02.c
> index 710e46e54..4c357c514 100644
> --- a/testcases/kernel/syscalls/madvise/madvise02.c
> +++ b/testcases/kernel/syscalls/madvise/madvise02.c
> @@ -25,6 +25,8 @@
>   *     locked or shared pages (with MADV_DONTNEED)
>   *  4. MADV_MERGEABLE or MADV_UNMERGEABLE was specified in advice,
>   *     but the kernel was not configured with CONFIG_KSM.
> + *  8|9. The MADV_FREE & MADV_WIPEONFORK operation can be applied
> + *  	only to private anonymous pages.
>   *
>   * (B) Test Case for ENOMEM
>   *  5|6. addresses in the specified range are not currently mapped
> @@ -51,6 +53,7 @@
>  #include "tst_test.h"
>  #include "lapi/mmap.h"
>  
> +#define MAP_SIZE (4 * 1024)
>  #define TEST_FILE "testfile"
>  #define STR "abcdefghijklmnopqrstuvwxyz12345\n"
>  #define KSM_SYS_DIR	"/sys/kernel/mm/ksm"
> @@ -59,6 +62,8 @@ static struct stat st;
>  static long pagesize;
>  static char *file1;
>  static char *file2;
> +static char *file3;
> +static char *shared_anon;
>  static char *ptr_addr;
>  static char *tmp_addr;
>  static char *nonalign;
> @@ -81,6 +86,8 @@ static struct tcase {
>  	{MADV_WILLNEED,    "MADV_WILLNEED",    &tmp_addr,  EBADF, 0},
>  	{MADV_FREE,        "MADV_FREE",        &file1,    EINVAL, 0},
>  	{MADV_WIPEONFORK,  "MADV_WIPEONFORK",  &file1,    EINVAL, 0},
> +	{MADV_WIPEONFORK,  "MADV_WIPEONFORK shared_anon", &shared_anon, EINVAL, 0},
> +	{MADV_WIPEONFORK,  "MADV_WIPEONFORK private file backed", &file3, EINVAL,
> 0},
>  };
>  
>  static void tcases_filter(void)
> @@ -151,6 +158,9 @@ static void setup(void)
>  	file1 = SAFE_MMAP(0, st.st_size, PROT_READ, MAP_SHARED, fd, 0);
>  	file2 = SAFE_MMAP(0, st.st_size, PROT_READ, MAP_SHARED, fd, 0);
>  	SAFE_MUNMAP(file2 + st.st_size - pagesize, pagesize);
> +	file3 = SAFE_MMAP(0, st.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
> +	shared_anon = SAFE_MMAP(0, MAP_SIZE, PROT_READ, MAP_SHARED |
> +			MAP_ANONYMOUS, -1, 0);
>  
>  	nonalign = file1 + 100;
>  
> @@ -192,6 +202,8 @@ static void cleanup(void)
>  	free(ptr_addr);
>  	SAFE_MUNMAP(file1, st.st_size);
>  	SAFE_MUNMAP(file2, st.st_size - pagesize);
> +	SAFE_MUNMAP(file3, st.st_size);
> +	SAFE_MUNMAP(shared_anon, MAP_SIZE);
>  }
>  
>  static struct tst_test test = {
> diff --git a/testcases/kernel/syscalls/madvise/madvise10.c
> b/testcases/kernel/syscalls/madvise/madvise10.c
> new file mode 100644
> index 000000000..2c3e5902e
> --- /dev/null
> +++ b/testcases/kernel/syscalls/madvise/madvise10.c
> @@ -0,0 +1,184 @@
> +// SPDX-License-Identifier: GPL-2.0 or later
> +/*
> + *  Copyright (c) Zilogic Systems Pvt. Ltd., 2018
> + *  Email : code@zilogic.com
> + *
> + * 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.
> + */
> +
> +/*
> + * test cases for madvise(2) system call, advise value as "MADV_WIPEONFORK".
> + *
> + * DESCRIPTION
> + * Present the child process with zero-filled memory in this
> + * range after a fork(2).
> + * The MADV_WIPEONFORK operation can be applied only to
> + * private anonymous pages.
> + * Within the child created by fork(2), the MADV_WIPEONFORK
> + * setting remains in place on the specified map_address range.
> + * The MADV_KEEPONFORK operation undo the effect of MADV_WIPEONFORK.
> + *
> + * Test-Case 1 : madvise with "MADV_WIPEONFORK"
> + * flow :	Map memory area as private anonymous page.
> + *		Mark memory area as wipe-on-fork.
> + *		On fork, child process memory should be zeroed.
> + *
> + * Test-Case 2 : madvise with "MADV_WIPEONFORK" as size "ZERO"
> + * flow :	Map memory area as private anonymous page.
> + *		Mark memory area as wipe-on-fork, with length zero.
> + *		On fork, child process memory should be accessible.
> + *
> + * Test-Case 3 : "MADV_WIPEONFORK" on Grand child
> + * flow :	Map memory area as private anonymous.
> + *		Mark memory areas as wipe-on-fork.
> + *		On fork, child process memory should be zeroed.
> + *		In child, fork to create grand-child,
> + *		memory should be zeroed.
> + *
> + * Test-Case 4 : Undo "MADV_WIPEONFORK" by "MADV_KEEPONFORK"
> + * flow :	Map memory area as private anonymous page.
> + *		Mark memory area as wipe-on-fork.
> + *		Mark memory area as keep-on-fork.
> + *		On fork, child process memory should be retained.
> + **/
> +
> +#include <stdio.h>
> +#include <signal.h>
> +#include <sys/types.h>
> +#include <sys/stat.h>
> +#include <fcntl.h>
> +#include <sys/mman.h>
> +#include <error.h>
> +#include <errno.h>
> +#include <unistd.h>
> +#include <sys/types.h>
> +#include <sys/wait.h>
> +#include <stdlib.h>
> +
> +#include "lapi/mmap.h"
> +#include "tst_test.h"
> +#include "tst_safe_macros.h"
> +
> +#define MAP_SIZE (4 * 1024)
> +
> +static char pattern[MAP_SIZE];
> +static char zero[MAP_SIZE];
> +
> +static const struct test_case {
> +	int size;
> +	int advise1;
> +	int advise2;
> +	char *exp;
> +	int grand_child;
> +} tcases[] = {
> +	{MAP_SIZE, MADV_NORMAL,	MADV_WIPEONFORK, zero,    0},
> +	{0,	   MADV_NORMAL, MADV_WIPEONFORK, pattern, 0},
> +	{MAP_SIZE, MADV_NORMAL, MADV_WIPEONFORK, zero,    1},
> +	{MAP_SIZE, MADV_WIPEONFORK, MADV_KEEPONFORK, pattern, 0},
> +};
> +
> +static void cmp_area(char *addr, const struct test_case *tc)
> +{
> +	int i;
> +
> +	for (i = 0; i < tc->size; i++) {
> +		if (addr[i] != tc->exp[i]) {
> +			tst_res(TFAIL, "In PID : %d Failed match", getpid());
> +			break;
> +		}
> +	}
> +
> +	tst_res(TPASS, "In PID : %d Matched expected pattern", getpid());
> +}
> +
> +static int set_advice(char *addr, int size, int advise)
> +{
> +	TEST(madvise(addr, size, advise));
> +
> +	if (TEST_RETURN == -1) {
> +		tst_res(TFAIL | TTERRNO, "failed :madvise(%p, %d, 0x%x)",
> +				addr, size, advise);
> +
> +		return 1;
> +	}
> +
> +	tst_res(TINFO, "success :madvise(%p, %d, 0x%x)",
> +			addr, size, advise);
> +	return 0;
> +}
> +
> +static char *mem_map(void)
> +{
> +	char *ptr;
> +
> +	ptr = SAFE_MMAP(NULL, MAP_SIZE,
> +			PROT_READ | PROT_WRITE,
> +			MAP_PRIVATE | MAP_ANONYMOUS,
> +			-1, 0);
> +
> +	memcpy(ptr, pattern, MAP_SIZE);
> +
> +	return ptr;
> +}
> +
> +static void test_madvise(unsigned int test_nr)
> +{
> +	const struct test_case *tc = &tcases[test_nr];
> +	char *addr;
> +	pid_t pid;
> +
> +	addr = mem_map();
> +
> +	if (set_advice(addr, tc->size, tc->advise1))
> +		goto un_map;
> +
> +	if (!set_advice(addr, tc->size, tc->advise2)) {
> +		tst_res(TINFO, "In %s process",
> +				tc->grand_child ? "grand_child" : "child");
> +
> +		pid = SAFE_FORK();
> +
> +		if (!pid) {
> +			if (tc->grand_child) {
> +				pid = SAFE_FORK();
> +
> +				if (!pid) {
> +					cmp_area(addr, tc);
> +					exit(0);
> +				}
> +			} else {
> +				cmp_area(addr, tc);
> +				exit(0);
> +			}
> +		}
> +		tst_reap_children();
> +	}
> +
> +un_map:
> +	SAFE_MUNMAP(addr, MAP_SIZE);
> +}
> +
> +static void setup(void)
> +{
> +	unsigned int i;
> +
> +	for (i = 0; i < MAP_SIZE; i++)
> +		pattern[i] = i % 0x02;
> +}
> +
> +static struct tst_test test = {
> +	.tcnt = ARRAY_SIZE(tcases),
> +	.forks_child = 1,
> +	.test = test_madvise,
> +	.setup = setup,
> +	.min_kver = "4.14",
> +};
> +
> --
> 2.11.0
> 
> --
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>