Commit 3a3a11e6 authored by Kees Cook's avatar Kees Cook Committed by Greg Kroah-Hartman
Browse files

lkdtm: Use init_uts_ns.name instead of macros 



Using generated/compile.h triggered a full LKDTM rebuild with every
build. Avoid this by using the exported strings instead.

Fixes: b8661450 ("lkdtm: Add kernel version to failure hints")
Signed-off-by: default avatarKees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20210901233406.2571643-1-keescook@chromium.org


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent bf9f243f

drivers/misc/lkdtm/core.c

+10 −0
Original line number Diff line number Diff line
@@ -26,6 +26,7 @@ 
#include <linux/init.h>

#include <linux/slab.h>

#include <linux/debugfs.h>

#include <linux/utsname.h>



#define DEFAULT_COUNT 10
@@ -210,6 +211,8 @@ module_param(cpoint_count, int, 0644); 
MODULE_PARM_DESC(cpoint_count, " Crash Point Count, number of times the "\

				"crash point is to be hit to trigger action");



/* For test debug reporting. */

char *lkdtm_kernel_info;



/* Return the crashtype number or NULL if the name is invalid */

static const struct crashtype *find_crashtype(const char *name)
@@ -490,6 +493,11 @@ static int __init lkdtm_module_init(void) 
	crash_count = cpoint_count;

#endif



	/* Common initialization. */

	lkdtm_kernel_info = kasprintf(GFP_KERNEL, "kernel (%s %s)",

				      init_uts_ns.name.release,

				      init_uts_ns.name.machine);



	/* Handle test-specific initialization. */

	lkdtm_bugs_init(&recur_count);

	lkdtm_perms_init();
@@ -538,6 +546,8 @@ static void __exit lkdtm_module_exit(void) 
	if (lkdtm_kprobe != NULL)

		unregister_kprobe(lkdtm_kprobe);



	kfree(lkdtm_kernel_info);



	pr_info("Crash point unregistered\n");

}

drivers/misc/lkdtm/lkdtm.h

+17 −11
Original line number Diff line number Diff line
@@ -5,17 +5,17 @@ 
#define pr_fmt(fmt) "lkdtm: " fmt



#include <linux/kernel.h>

#include <generated/compile.h>

#include <generated/utsrelease.h>



#define LKDTM_KERNEL "kernel (" UTS_RELEASE " " UTS_MACHINE ")"

extern char *lkdtm_kernel_info;



#define pr_expected_config(kconfig)				\

{								\

	if (IS_ENABLED(kconfig)) 				\

		pr_err("Unexpected! This " LKDTM_KERNEL " was built with " #kconfig "=y\n"); \

		pr_err("Unexpected! This %s was built with " #kconfig "=y\n", \

			lkdtm_kernel_info);			\

	else							\

		pr_warn("This is probably expected, since this " LKDTM_KERNEL " was built *without* " #kconfig "=y\n"); \

		pr_warn("This is probably expected, since this %s was built *without* " #kconfig "=y\n", \

			lkdtm_kernel_info);			\

}



#ifndef MODULE
@@ -25,24 +25,30 @@ int lkdtm_check_bool_cmdline(const char *param); 
	if (IS_ENABLED(kconfig)) {				\

		switch (lkdtm_check_bool_cmdline(param)) {	\

		case 0:						\

			pr_warn("This is probably expected, since this " LKDTM_KERNEL " was built with " #kconfig "=y but booted with '" param "=N'\n"); \

			pr_warn("This is probably expected, since this %s was built with " #kconfig "=y but booted with '" param "=N'\n", \

				lkdtm_kernel_info);		\

			break;					\

		case 1:						\

			pr_err("Unexpected! This " LKDTM_KERNEL " was built with " #kconfig "=y and booted with '" param "=Y'\n"); \

			pr_err("Unexpected! This %s was built with " #kconfig "=y and booted with '" param "=Y'\n", \

				lkdtm_kernel_info);		\

			break;					\

		default:					\

			pr_err("Unexpected! This " LKDTM_KERNEL " was built with " #kconfig "=y (and booted without '" param "' specified)\n"); \

			pr_err("Unexpected! This %s was built with " #kconfig "=y (and booted without '" param "' specified)\n", \

				lkdtm_kernel_info);		\

		}						\

	} else {						\

		switch (lkdtm_check_bool_cmdline(param)) {	\

		case 0:						\

			pr_warn("This is probably expected, as this " LKDTM_KERNEL " was built *without* " #kconfig "=y and booted with '" param "=N'\n"); \

			pr_warn("This is probably expected, as this %s was built *without* " #kconfig "=y and booted with '" param "=N'\n", \

				lkdtm_kernel_info);		\

			break;					\

		case 1:						\

			pr_err("Unexpected! This " LKDTM_KERNEL " was built *without* " #kconfig "=y but booted with '" param "=Y'\n"); \

			pr_err("Unexpected! This %s was built *without* " #kconfig "=y but booted with '" param "=Y'\n", \

				lkdtm_kernel_info);		\

			break;					\

		default:					\

			pr_err("This is probably expected, since this " LKDTM_KERNEL " was built *without* " #kconfig "=y (and booted without '" param "' specified)\n"); \

			pr_err("This is probably expected, since this %s was built *without* " #kconfig "=y (and booted without '" param "' specified)\n", \

				lkdtm_kernel_info);		\

			break;					\

		}						\

	}							\