u-boot/cmd/stackprot_test.c
Tom Rini 2fc62f2991 stackprot: Make our test a bit more complex
With better compiler optimizations available, a compiler may see we do
nothing with our buffer after calling memset and omit the call, thus
causing us to not smash the stack.  Add a comment to explain why we now
also have a printf call, so that the test will pass as the memset will
not be omitted.

Reported-by: Marek Behún <marek.behun@nic.cz>
Signed-off-by: Tom Rini <trini@konsulko.com>
2021-05-24 14:23:01 -04:00

26 lines
594 B
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright 2021 Broadcom
*/
#include <common.h>
#include <command.h>
static int do_test_stackprot_fail(struct cmd_tbl *cmdtp, int flag, int argc,
char *const argv[])
{
/*
* In order to avoid having the compiler optimize away the stack smashing
* we need to do a little something here.
*/
char a[128];
memset(a, 0xa5, 512);
printf("We have smashed our stack as this should not exceed 128: sizeof(a) = %ld\n", strlen(a));
return 0;
}
U_BOOT_CMD(stackprot_test, 1, 1, do_test_stackprot_fail,
"test stack protector fail", "");