linux/mm/rodata_test.c
Jinbum Park 2959a5f726 mm: add arch-independent testcases for RODATA
This patch makes arch-independent testcases for RODATA.  Both x86 and
x86_64 already have testcases for RODATA, But they are arch-specific
because using inline assembly directly.

And cacheflush.h is not a suitable location for rodata-test related
things.  Since they were in cacheflush.h, If someone change the state of
CONFIG_DEBUG_RODATA_TEST, It cause overhead of kernel build.

To solve the above issues, write arch-independent testcases and move it
to shared location.

[jinb.park7@gmail.com: fix config dependency]
  Link: http://lkml.kernel.org/r/20170209131625.GA16954@pjb1027-Latitude-E5410
Link: http://lkml.kernel.org/r/20170129105436.GA9303@pjb1027-Latitude-E5410
Signed-off-by: Jinbum Park <jinb.park7@gmail.com>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Laura Abbott <labbott@redhat.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Valentin Rothberg <valentinrothberg@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-27 18:43:48 -08:00

56 lines
1.5 KiB
C

/*
* rodata_test.c: functional test for mark_rodata_ro function
*
* (C) Copyright 2008 Intel Corporation
* Author: Arjan van de Ven <arjan@linux.intel.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; version 2
* of the License.
*/
#include <linux/uaccess.h>
#include <asm/sections.h>
const int rodata_test_data = 0xC3;
EXPORT_SYMBOL_GPL(rodata_test_data);
void rodata_test(void)
{
unsigned long start, end;
int zero = 0;
/* test 1: read the value */
/* If this test fails, some previous testrun has clobbered the state */
if (!rodata_test_data) {
pr_err("rodata_test: test 1 fails (start data)\n");
return;
}
/* test 2: write to the variable; this should fault */
if (!probe_kernel_write((void *)&rodata_test_data,
(void *)&zero, sizeof(zero))) {
pr_err("rodata_test: test data was not read only\n");
return;
}
/* test 3: check the value hasn't changed */
if (rodata_test_data == zero) {
pr_err("rodata_test: test data was changed\n");
return;
}
/* test 4: check if the rodata section is PAGE_SIZE aligned */
start = (unsigned long)__start_rodata;
end = (unsigned long)__end_rodata;
if (start & (PAGE_SIZE - 1)) {
pr_err("rodata_test: start of .rodata is not page size aligned\n");
return;
}
if (end & (PAGE_SIZE - 1)) {
pr_err("rodata_test: end of .rodata is not page size aligned\n");
return;
}
pr_info("rodata_test: all tests were successful\n");
}