From 5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sat, 27 Apr 2024 12:05:51 +0200 Subject: Adding upstream version 5.10.209. Signed-off-by: Daniel Baumann --- drivers/misc/lkdtm/cfi.c | 42 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 42 insertions(+) create mode 100644 drivers/misc/lkdtm/cfi.c (limited to 'drivers/misc/lkdtm/cfi.c') diff --git a/drivers/misc/lkdtm/cfi.c b/drivers/misc/lkdtm/cfi.c new file mode 100644 index 000000000..e73ebdbfa --- /dev/null +++ b/drivers/misc/lkdtm/cfi.c @@ -0,0 +1,42 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * This is for all the tests relating directly to Control Flow Integrity. + */ +#include "lkdtm.h" + +static int called_count; + +/* Function taking one argument, without a return value. */ +static noinline void lkdtm_increment_void(int *counter) +{ + (*counter)++; +} + +/* Function taking one argument, returning int. */ +static noinline int lkdtm_increment_int(int *counter) +{ + (*counter)++; + + return *counter; +} +/* + * This tries to call an indirect function with a mismatched prototype. + */ +void lkdtm_CFI_FORWARD_PROTO(void) +{ + /* + * Matches lkdtm_increment_void()'s prototype, but not + * lkdtm_increment_int()'s prototype. + */ + void (*func)(int *); + + pr_info("Calling matched prototype ...\n"); + func = lkdtm_increment_void; + func(&called_count); + + pr_info("Calling mismatched prototype ...\n"); + func = (void *)lkdtm_increment_int; + func(&called_count); + + pr_info("Fail: survived mismatched prototype function call!\n"); +} -- cgit v1.2.3