Commit d8a54d2e authored by Greg Kroah-Hartman's avatar Greg Kroah-Hartman
Browse files

Merge tag 'lkdtm-next' of... 

Merge tag 'lkdtm-next' of https://git.kernel.org/pub/scm/linux/kernel/git/kees/linux into char-misc-next

Kees writes:

lkdtm updates for next

Christophe Leroy (1):
      lkdtm/bugs: Don't expect thread termination without CONFIG_UBSAN_TRAP

Jiasheng Jiang (1):
      lkdtm/bugs: Check for the NULL pointer after calling kmalloc

Kees Cook (4):
      lkdtm/heap: Note conditions for SLAB_LINEAR_OVERFLOW
      lkdtm/usercopy: Expand size of "out of frame" object
      lkdtm: Move crashtype definitions into each category
      lkdtm: Add CFI_BACKWARD to test ROP mitigations

* tag 'lkdtm-next' of https://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
  lkdtm: Add CFI_BACKWARD to test ROP mitigations
  lkdtm: Move crashtype definitions into each category
  lkdtm/bugs: Don't expect thread termination without CONFIG_UBSAN_TRAP
  lkdtm/usercopy: Expand size of "out of frame" object
  lkdtm/heap: Note conditions for SLAB_LINEAR_OVERFLOW
  lkdtm/bugs: Check for the NULL pointer after calling kmalloc
parents c50c29a8 2e53b877

drivers/misc/lkdtm/bugs.c

+69 −27
Original line number Diff line number Diff line
@@ -68,40 +68,40 @@ void __init lkdtm_bugs_init(int *recur_param) 
		recur_count = *recur_param;

}



void lkdtm_PANIC(void)

static void lkdtm_PANIC(void)

{

	panic("dumptest");

}



void lkdtm_BUG(void)

static void lkdtm_BUG(void)

{

	BUG();

}



static int warn_counter;



void lkdtm_WARNING(void)

static void lkdtm_WARNING(void)

{

	WARN_ON(++warn_counter);

}



void lkdtm_WARNING_MESSAGE(void)

static void lkdtm_WARNING_MESSAGE(void)

{

	WARN(1, "Warning message trigger count: %d\n", ++warn_counter);

}



void lkdtm_EXCEPTION(void)

static void lkdtm_EXCEPTION(void)

{

	*((volatile int *) 0) = 0;

}



void lkdtm_LOOP(void)

static void lkdtm_LOOP(void)

{

	for (;;)

		;

}



void lkdtm_EXHAUST_STACK(void)

static void lkdtm_EXHAUST_STACK(void)

{

	pr_info("Calling function with %lu frame size to depth %d ...\n",

		REC_STACK_SIZE, recur_count);
@@ -115,7 +115,7 @@ static noinline void __lkdtm_CORRUPT_STACK(void *stack) 
}



/* This should trip the stack canary, not corrupt the return address. */

noinline void lkdtm_CORRUPT_STACK(void)

static noinline void lkdtm_CORRUPT_STACK(void)

{

	/* Use default char array length that triggers stack protection. */

	char data[8] __aligned(sizeof(void *));
@@ -125,7 +125,7 @@ noinline void lkdtm_CORRUPT_STACK(void) 
}



/* Same as above but will only get a canary with -fstack-protector-strong */

noinline void lkdtm_CORRUPT_STACK_STRONG(void)

static noinline void lkdtm_CORRUPT_STACK_STRONG(void)

{

	union {

		unsigned short shorts[4];
@@ -139,7 +139,7 @@ noinline void lkdtm_CORRUPT_STACK_STRONG(void) 
static pid_t stack_pid;

static unsigned long stack_addr;



void lkdtm_REPORT_STACK(void)

static void lkdtm_REPORT_STACK(void)

{

	volatile uintptr_t magic;

	pid_t pid = task_pid_nr(current);
@@ -222,7 +222,7 @@ static noinline void __lkdtm_REPORT_STACK_CANARY(void *stack) 
	}

}



void lkdtm_REPORT_STACK_CANARY(void)

static void lkdtm_REPORT_STACK_CANARY(void)

{

	/* Use default char array length that triggers stack protection. */

	char data[8] __aligned(sizeof(void *)) = { };
@@ -230,7 +230,7 @@ void lkdtm_REPORT_STACK_CANARY(void) 
	__lkdtm_REPORT_STACK_CANARY((void *)&data);

}



void lkdtm_UNALIGNED_LOAD_STORE_WRITE(void)

static void lkdtm_UNALIGNED_LOAD_STORE_WRITE(void)

{

	static u8 data[5] __attribute__((aligned(4))) = {1, 2, 3, 4, 5};

	u32 *p;
@@ -245,21 +245,21 @@ void lkdtm_UNALIGNED_LOAD_STORE_WRITE(void) 
		pr_err("XFAIL: arch has CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS\n");

}



void lkdtm_SOFTLOCKUP(void)

static void lkdtm_SOFTLOCKUP(void)

{

	preempt_disable();

	for (;;)

		cpu_relax();

}



void lkdtm_HARDLOCKUP(void)

static void lkdtm_HARDLOCKUP(void)

{

	local_irq_disable();

	for (;;)

		cpu_relax();

}



void lkdtm_SPINLOCKUP(void)

static void lkdtm_SPINLOCKUP(void)

{

	/* Must be called twice to trigger. */

	spin_lock(&lock_me_up);
@@ -267,7 +267,7 @@ void lkdtm_SPINLOCKUP(void) 
	__release(&lock_me_up);

}



void lkdtm_HUNG_TASK(void)

static void lkdtm_HUNG_TASK(void)

{

	set_current_state(TASK_UNINTERRUPTIBLE);

	schedule();
@@ -276,7 +276,7 @@ void lkdtm_HUNG_TASK(void) 
volatile unsigned int huge = INT_MAX - 2;

volatile unsigned int ignored;



void lkdtm_OVERFLOW_SIGNED(void)

static void lkdtm_OVERFLOW_SIGNED(void)

{

	int value;
@@ -291,7 +291,7 @@ void lkdtm_OVERFLOW_SIGNED(void) 
}





void lkdtm_OVERFLOW_UNSIGNED(void)

static void lkdtm_OVERFLOW_UNSIGNED(void)

{

	unsigned int value;
@@ -319,7 +319,7 @@ struct array_bounds { 
	int three;

};



void lkdtm_ARRAY_BOUNDS(void)

static void lkdtm_ARRAY_BOUNDS(void)

{

	struct array_bounds_flex_array *not_checked;

	struct array_bounds *checked;
@@ -327,6 +327,11 @@ void lkdtm_ARRAY_BOUNDS(void) 


	not_checked = kmalloc(sizeof(*not_checked) * 2, GFP_KERNEL);

	checked = kmalloc(sizeof(*checked) * 2, GFP_KERNEL);

	if (!not_checked || !checked) {

		kfree(not_checked);

		kfree(checked);

		return;

	}



	pr_info("Array access within bounds ...\n");

	/* For both, touch all bytes in the actual member size. */
@@ -346,10 +351,13 @@ void lkdtm_ARRAY_BOUNDS(void) 
	kfree(not_checked);

	kfree(checked);

	pr_err("FAIL: survived array bounds overflow!\n");

	if (IS_ENABLED(CONFIG_UBSAN_BOUNDS))

		pr_expected_config(CONFIG_UBSAN_TRAP);

	else

		pr_expected_config(CONFIG_UBSAN_BOUNDS);

}



void lkdtm_CORRUPT_LIST_ADD(void)

static void lkdtm_CORRUPT_LIST_ADD(void)

{

	/*

	 * Initially, an empty list via LIST_HEAD:
@@ -389,7 +397,7 @@ void lkdtm_CORRUPT_LIST_ADD(void) 
	}

}



void lkdtm_CORRUPT_LIST_DEL(void)

static void lkdtm_CORRUPT_LIST_DEL(void)

{

	LIST_HEAD(test_head);

	struct lkdtm_list item;
@@ -417,7 +425,7 @@ void lkdtm_CORRUPT_LIST_DEL(void) 
}



/* Test that VMAP_STACK is actually allocating with a leading guard page */

void lkdtm_STACK_GUARD_PAGE_LEADING(void)

static void lkdtm_STACK_GUARD_PAGE_LEADING(void)

{

	const unsigned char *stack = task_stack_page(current);

	const unsigned char *ptr = stack - 1;
@@ -431,7 +439,7 @@ void lkdtm_STACK_GUARD_PAGE_LEADING(void) 
}



/* Test that VMAP_STACK is actually allocating with a trailing guard page */

void lkdtm_STACK_GUARD_PAGE_TRAILING(void)

static void lkdtm_STACK_GUARD_PAGE_TRAILING(void)

{

	const unsigned char *stack = task_stack_page(current);

	const unsigned char *ptr = stack + THREAD_SIZE;
@@ -444,7 +452,7 @@ void lkdtm_STACK_GUARD_PAGE_TRAILING(void) 
	pr_err("FAIL: accessed page after stack! (byte: %x)\n", byte);

}



void lkdtm_UNSET_SMEP(void)

static void lkdtm_UNSET_SMEP(void)

{

#if IS_ENABLED(CONFIG_X86_64) && !IS_ENABLED(CONFIG_UML)

#define MOV_CR4_DEPTH	64
@@ -510,7 +518,7 @@ void lkdtm_UNSET_SMEP(void) 
#endif

}



void lkdtm_DOUBLE_FAULT(void)

static void lkdtm_DOUBLE_FAULT(void)

{

#if IS_ENABLED(CONFIG_X86_32) && !IS_ENABLED(CONFIG_UML)

	/*
@@ -558,7 +566,7 @@ static noinline void change_pac_parameters(void) 
}

#endif



noinline void lkdtm_CORRUPT_PAC(void)

static noinline void lkdtm_CORRUPT_PAC(void)

{

#ifdef CONFIG_ARM64

#define CORRUPT_PAC_ITERATE	10
@@ -586,3 +594,37 @@ noinline void lkdtm_CORRUPT_PAC(void) 
	pr_err("XFAIL: this test is arm64-only\n");

#endif

}



static struct crashtype crashtypes[] = {

	CRASHTYPE(PANIC),

	CRASHTYPE(BUG),

	CRASHTYPE(WARNING),

	CRASHTYPE(WARNING_MESSAGE),

	CRASHTYPE(EXCEPTION),

	CRASHTYPE(LOOP),

	CRASHTYPE(EXHAUST_STACK),

	CRASHTYPE(CORRUPT_STACK),

	CRASHTYPE(CORRUPT_STACK_STRONG),

	CRASHTYPE(REPORT_STACK),

	CRASHTYPE(REPORT_STACK_CANARY),

	CRASHTYPE(UNALIGNED_LOAD_STORE_WRITE),

	CRASHTYPE(SOFTLOCKUP),

	CRASHTYPE(HARDLOCKUP),

	CRASHTYPE(SPINLOCKUP),

	CRASHTYPE(HUNG_TASK),

	CRASHTYPE(OVERFLOW_SIGNED),

	CRASHTYPE(OVERFLOW_UNSIGNED),

	CRASHTYPE(ARRAY_BOUNDS),

	CRASHTYPE(CORRUPT_LIST_ADD),

	CRASHTYPE(CORRUPT_LIST_DEL),

	CRASHTYPE(STACK_GUARD_PAGE_LEADING),

	CRASHTYPE(STACK_GUARD_PAGE_TRAILING),

	CRASHTYPE(UNSET_SMEP),

	CRASHTYPE(DOUBLE_FAULT),

	CRASHTYPE(CORRUPT_PAC),

};



struct crashtype_category bugs_crashtypes = {

	.crashtypes = crashtypes,

	.len	    = ARRAY_SIZE(crashtypes),

};

drivers/misc/lkdtm/cfi.c

+144 −1
Original line number Diff line number Diff line
@@ -3,6 +3,7 @@ 
 * This is for all the tests relating directly to Control Flow Integrity.

 */

#include "lkdtm.h"

#include <asm/page.h>



static int called_count;
@@ -22,7 +23,7 @@ static noinline int lkdtm_increment_int(int *counter) 
/*

 * This tries to call an indirect function with a mismatched prototype.

 */

void lkdtm_CFI_FORWARD_PROTO(void)

static void lkdtm_CFI_FORWARD_PROTO(void)

{

	/*

	 * Matches lkdtm_increment_void()'s prototype, but not
@@ -41,3 +42,145 @@ void lkdtm_CFI_FORWARD_PROTO(void) 
	pr_err("FAIL: survived mismatched prototype function call!\n");

	pr_expected_config(CONFIG_CFI_CLANG);

}



/*

 * This can stay local to LKDTM, as there should not be a production reason

 * to disable PAC && SCS.

 */

#ifdef CONFIG_ARM64_PTR_AUTH_KERNEL

# ifdef CONFIG_ARM64_BTI_KERNEL

#  define __no_pac             "branch-protection=bti"

# else

#  define __no_pac             "branch-protection=none"

# endif

# define __no_ret_protection   __noscs __attribute__((__target__(__no_pac)))

#else

# define __no_ret_protection   __noscs

#endif



#define no_pac_addr(addr)      \

	((__force __typeof__(addr))((__force u64)(addr) | PAGE_OFFSET))



/* The ultimate ROP gadget. */

static noinline __no_ret_protection

void set_return_addr_unchecked(unsigned long *expected, unsigned long *addr)

{

	/* Use of volatile is to make sure final write isn't seen as a dead store. */

	unsigned long * volatile *ret_addr = (unsigned long **)__builtin_frame_address(0) + 1;



	/* Make sure we've found the right place on the stack before writing it. */

	if (no_pac_addr(*ret_addr) == expected)

		*ret_addr = (addr);

	else

		/* Check architecture, stack layout, or compiler behavior... */

		pr_warn("Eek: return address mismatch! %px != %px\n",

			*ret_addr, addr);

}



static noinline

void set_return_addr(unsigned long *expected, unsigned long *addr)

{

	/* Use of volatile is to make sure final write isn't seen as a dead store. */

	unsigned long * volatile *ret_addr = (unsigned long **)__builtin_frame_address(0) + 1;



	/* Make sure we've found the right place on the stack before writing it. */

	if (no_pac_addr(*ret_addr) == expected)

		*ret_addr = (addr);

	else

		/* Check architecture, stack layout, or compiler behavior... */

		pr_warn("Eek: return address mismatch! %px != %px\n",

			*ret_addr, addr);

}



static volatile int force_check;



static void lkdtm_CFI_BACKWARD(void)

{

	/* Use calculated gotos to keep labels addressable. */

	void *labels[] = {0, &&normal, &&redirected, &&check_normal, &&check_redirected};



	pr_info("Attempting unchecked stack return address redirection ...\n");



	/* Always false */

	if (force_check) {

		/*

		 * Prepare to call with NULLs to avoid parameters being treated as

		 * constants in -02.

		 */

		set_return_addr_unchecked(NULL, NULL);

		set_return_addr(NULL, NULL);

		if (force_check)

			goto *labels[1];

		if (force_check)

			goto *labels[2];

		if (force_check)

			goto *labels[3];

		if (force_check)

			goto *labels[4];

		return;

	}



	/*

	 * Use fallthrough switch case to keep basic block ordering between

	 * set_return_addr*() and the label after it.

	 */

	switch (force_check) {

	case 0:

		set_return_addr_unchecked(&&normal, &&redirected);

		fallthrough;

	case 1:

normal:

		/* Always true */

		if (!force_check) {

			pr_err("FAIL: stack return address manipulation failed!\n");

			/* If we can't redirect "normally", we can't test mitigations. */

			return;

		}

		break;

	default:

redirected:

		pr_info("ok: redirected stack return address.\n");

		break;

	}



	pr_info("Attempting checked stack return address redirection ...\n");



	switch (force_check) {

	case 0:

		set_return_addr(&&check_normal, &&check_redirected);

		fallthrough;

	case 1:

check_normal:

		/* Always true */

		if (!force_check) {

			pr_info("ok: control flow unchanged.\n");

			return;

		}



check_redirected:

		pr_err("FAIL: stack return address was redirected!\n");

		break;

	}



	if (IS_ENABLED(CONFIG_ARM64_PTR_AUTH_KERNEL)) {

		pr_expected_config(CONFIG_ARM64_PTR_AUTH_KERNEL);

		return;

	}

	if (IS_ENABLED(CONFIG_SHADOW_CALL_STACK)) {

		pr_expected_config(CONFIG_SHADOW_CALL_STACK);

		return;

	}

	pr_warn("This is probably expected, since this %s was built *without* %s=y nor %s=y\n",

		lkdtm_kernel_info,

		"CONFIG_ARM64_PTR_AUTH_KERNEL", "CONFIG_SHADOW_CALL_STACK");

}



static struct crashtype crashtypes[] = {

	CRASHTYPE(CFI_FORWARD_PROTO),

	CRASHTYPE(CFI_BACKWARD),

};



struct crashtype_category cfi_crashtypes = {

	.crashtypes = crashtypes,

	.len	    = ARRAY_SIZE(crashtypes),

};

drivers/misc/lkdtm/core.c

+31 −107
Original line number Diff line number Diff line
@@ -86,109 +86,21 @@ static struct crashpoint crashpoints[] = { 
#endif

};





/* Crash types. */

struct crashtype {

	const char *name;

	void (*func)(void);

};



#define CRASHTYPE(_name)			\

	{					\

		.name = __stringify(_name),	\

		.func = lkdtm_ ## _name,	\

	}



/* Define the possible types of crashes that can be triggered. */

static const struct crashtype crashtypes[] = {

	CRASHTYPE(PANIC),

	CRASHTYPE(BUG),

	CRASHTYPE(WARNING),

	CRASHTYPE(WARNING_MESSAGE),

	CRASHTYPE(EXCEPTION),

	CRASHTYPE(LOOP),

	CRASHTYPE(EXHAUST_STACK),

	CRASHTYPE(CORRUPT_STACK),

	CRASHTYPE(CORRUPT_STACK_STRONG),

	CRASHTYPE(REPORT_STACK),

	CRASHTYPE(REPORT_STACK_CANARY),

	CRASHTYPE(CORRUPT_LIST_ADD),

	CRASHTYPE(CORRUPT_LIST_DEL),

	CRASHTYPE(STACK_GUARD_PAGE_LEADING),

	CRASHTYPE(STACK_GUARD_PAGE_TRAILING),

	CRASHTYPE(UNSET_SMEP),

	CRASHTYPE(CORRUPT_PAC),

	CRASHTYPE(UNALIGNED_LOAD_STORE_WRITE),

	CRASHTYPE(SLAB_LINEAR_OVERFLOW),

	CRASHTYPE(VMALLOC_LINEAR_OVERFLOW),

	CRASHTYPE(WRITE_AFTER_FREE),

	CRASHTYPE(READ_AFTER_FREE),

	CRASHTYPE(WRITE_BUDDY_AFTER_FREE),

	CRASHTYPE(READ_BUDDY_AFTER_FREE),

	CRASHTYPE(SLAB_INIT_ON_ALLOC),

	CRASHTYPE(BUDDY_INIT_ON_ALLOC),

	CRASHTYPE(SLAB_FREE_DOUBLE),

	CRASHTYPE(SLAB_FREE_CROSS),

	CRASHTYPE(SLAB_FREE_PAGE),

	CRASHTYPE(SOFTLOCKUP),

	CRASHTYPE(HARDLOCKUP),

	CRASHTYPE(SPINLOCKUP),

	CRASHTYPE(HUNG_TASK),

	CRASHTYPE(OVERFLOW_SIGNED),

	CRASHTYPE(OVERFLOW_UNSIGNED),

	CRASHTYPE(ARRAY_BOUNDS),

	CRASHTYPE(EXEC_DATA),

	CRASHTYPE(EXEC_STACK),

	CRASHTYPE(EXEC_KMALLOC),

	CRASHTYPE(EXEC_VMALLOC),

	CRASHTYPE(EXEC_RODATA),

	CRASHTYPE(EXEC_USERSPACE),

	CRASHTYPE(EXEC_NULL),

	CRASHTYPE(ACCESS_USERSPACE),

	CRASHTYPE(ACCESS_NULL),

	CRASHTYPE(WRITE_RO),

	CRASHTYPE(WRITE_RO_AFTER_INIT),

	CRASHTYPE(WRITE_KERN),

	CRASHTYPE(WRITE_OPD),

	CRASHTYPE(REFCOUNT_INC_OVERFLOW),

	CRASHTYPE(REFCOUNT_ADD_OVERFLOW),

	CRASHTYPE(REFCOUNT_INC_NOT_ZERO_OVERFLOW),

	CRASHTYPE(REFCOUNT_ADD_NOT_ZERO_OVERFLOW),

	CRASHTYPE(REFCOUNT_DEC_ZERO),

	CRASHTYPE(REFCOUNT_DEC_NEGATIVE),

	CRASHTYPE(REFCOUNT_DEC_AND_TEST_NEGATIVE),

	CRASHTYPE(REFCOUNT_SUB_AND_TEST_NEGATIVE),

	CRASHTYPE(REFCOUNT_INC_ZERO),

	CRASHTYPE(REFCOUNT_ADD_ZERO),

	CRASHTYPE(REFCOUNT_INC_SATURATED),

	CRASHTYPE(REFCOUNT_DEC_SATURATED),

	CRASHTYPE(REFCOUNT_ADD_SATURATED),

	CRASHTYPE(REFCOUNT_INC_NOT_ZERO_SATURATED),

	CRASHTYPE(REFCOUNT_ADD_NOT_ZERO_SATURATED),

	CRASHTYPE(REFCOUNT_DEC_AND_TEST_SATURATED),

	CRASHTYPE(REFCOUNT_SUB_AND_TEST_SATURATED),

	CRASHTYPE(REFCOUNT_TIMING),

	CRASHTYPE(ATOMIC_TIMING),

	CRASHTYPE(USERCOPY_HEAP_SIZE_TO),

	CRASHTYPE(USERCOPY_HEAP_SIZE_FROM),

	CRASHTYPE(USERCOPY_HEAP_WHITELIST_TO),

	CRASHTYPE(USERCOPY_HEAP_WHITELIST_FROM),

	CRASHTYPE(USERCOPY_STACK_FRAME_TO),

	CRASHTYPE(USERCOPY_STACK_FRAME_FROM),

	CRASHTYPE(USERCOPY_STACK_BEYOND),

	CRASHTYPE(USERCOPY_KERNEL),

	CRASHTYPE(STACKLEAK_ERASING),

	CRASHTYPE(CFI_FORWARD_PROTO),

	CRASHTYPE(FORTIFIED_OBJECT),

	CRASHTYPE(FORTIFIED_SUBOBJECT),

	CRASHTYPE(FORTIFIED_STRSCPY),

	CRASHTYPE(DOUBLE_FAULT),

/* List of possible types for crashes that can be triggered. */

static const struct crashtype_category *crashtype_categories[] = {

	&bugs_crashtypes,

	&heap_crashtypes,

	&perms_crashtypes,

	&refcount_crashtypes,

	&usercopy_crashtypes,

	&stackleak_crashtypes,

	&cfi_crashtypes,

	&fortify_crashtypes,

#ifdef CONFIG_PPC_64S_HASH_MMU

	CRASHTYPE(PPC_SLB_MULTIHIT),

	&powerpc_crashtypes,

#endif

};





/* Global kprobe entry and crashtype. */

static struct kprobe *lkdtm_kprobe;

static struct crashpoint *lkdtm_crashpoint;
@@ -223,11 +135,16 @@ char *lkdtm_kernel_info; 
/* Return the crashtype number or NULL if the name is invalid */

static const struct crashtype *find_crashtype(const char *name)

{

	int i;

	int cat, idx;



	for (cat = 0; cat < ARRAY_SIZE(crashtype_categories); cat++) {

		for (idx = 0; idx < crashtype_categories[cat]->len; idx++) {

			struct crashtype *crashtype;



	for (i = 0; i < ARRAY_SIZE(crashtypes); i++) {

		if (!strcmp(name, crashtypes[i].name))

			return &crashtypes[i];

			crashtype = &crashtype_categories[cat]->crashtypes[idx];

			if (!strcmp(name, crashtype->name))

				return crashtype;

		}

	}



	return NULL;
@@ -347,17 +264,24 @@ static ssize_t lkdtm_debugfs_entry(struct file *f, 
static ssize_t lkdtm_debugfs_read(struct file *f, char __user *user_buf,

		size_t count, loff_t *off)

{

	int n, cat, idx;

	ssize_t out;

	char *buf;

	int i, n, out;



	buf = (char *)__get_free_page(GFP_KERNEL);

	if (buf == NULL)

		return -ENOMEM;



	n = scnprintf(buf, PAGE_SIZE, "Available crash types:\n");

	for (i = 0; i < ARRAY_SIZE(crashtypes); i++) {



	for (cat = 0; cat < ARRAY_SIZE(crashtype_categories); cat++) {

		for (idx = 0; idx < crashtype_categories[cat]->len; idx++) {

			struct crashtype *crashtype;



			crashtype = &crashtype_categories[cat]->crashtypes[idx];

			n += scnprintf(buf + n, PAGE_SIZE - n, "%s\n",

			      crashtypes[i].name);

				      crashtype->name);

		}

	}

	buf[n] = '\0';

drivers/misc/lkdtm/fortify.c

+14 −3
Original line number Diff line number Diff line
@@ -10,7 +10,7 @@ 


static volatile int fortify_scratch_space;



void lkdtm_FORTIFIED_OBJECT(void)

static void lkdtm_FORTIFIED_OBJECT(void)

{

	struct target {

		char a[10];
@@ -31,7 +31,7 @@ void lkdtm_FORTIFIED_OBJECT(void) 
	pr_expected_config(CONFIG_FORTIFY_SOURCE);

}



void lkdtm_FORTIFIED_SUBOBJECT(void)

static void lkdtm_FORTIFIED_SUBOBJECT(void)

{

	struct target {

		char a[10];
@@ -67,7 +67,7 @@ void lkdtm_FORTIFIED_SUBOBJECT(void) 
 * strscpy and generate a panic because there is a write overflow (i.e. src

 * length is greater than dst length).

 */

void lkdtm_FORTIFIED_STRSCPY(void)

static void lkdtm_FORTIFIED_STRSCPY(void)

{

	char *src;

	char dst[5];
@@ -134,3 +134,14 @@ void lkdtm_FORTIFIED_STRSCPY(void) 


	kfree(src);

}



static struct crashtype crashtypes[] = {

	CRASHTYPE(FORTIFIED_OBJECT),

	CRASHTYPE(FORTIFIED_SUBOBJECT),

	CRASHTYPE(FORTIFIED_STRSCPY),

};



struct crashtype_category fortify_crashtypes = {

	.crashtypes = crashtypes,

	.len	    = ARRAY_SIZE(crashtypes),

};

drivers/misc/lkdtm/heap.c

+36 −11
Original line number Diff line number Diff line
@@ -22,8 +22,11 @@ static volatile int __offset = 1; 
/*

 * If there aren't guard pages, it's likely that a consecutive allocation will

 * let us overflow into the second allocation without overwriting something real.

 *

 * This should always be caught because there is an unconditional unmapped

 * page after vmap allocations.

 */

void lkdtm_VMALLOC_LINEAR_OVERFLOW(void)

static void lkdtm_VMALLOC_LINEAR_OVERFLOW(void)

{

	char *one, *two;
@@ -41,8 +44,11 @@ void lkdtm_VMALLOC_LINEAR_OVERFLOW(void) 
 * This tries to stay within the next largest power-of-2 kmalloc cache

 * to avoid actually overwriting anything important if it's not detected

 * correctly.

 *

 * This should get caught by either memory tagging, KASan, or by using

 * CONFIG_SLUB_DEBUG=y and slub_debug=ZF (or CONFIG_SLUB_DEBUG_ON=y).

 */

void lkdtm_SLAB_LINEAR_OVERFLOW(void)

static void lkdtm_SLAB_LINEAR_OVERFLOW(void)

{

	size_t len = 1020;

	u32 *data = kmalloc(len, GFP_KERNEL);
@@ -54,7 +60,7 @@ void lkdtm_SLAB_LINEAR_OVERFLOW(void) 
	kfree(data);

}



void lkdtm_WRITE_AFTER_FREE(void)

static void lkdtm_WRITE_AFTER_FREE(void)

{

	int *base, *again;

	size_t len = 1024;
@@ -80,7 +86,7 @@ void lkdtm_WRITE_AFTER_FREE(void) 
		pr_info("Hmm, didn't get the same memory range.\n");

}



void lkdtm_READ_AFTER_FREE(void)

static void lkdtm_READ_AFTER_FREE(void)

{

	int *base, *val, saw;

	size_t len = 1024;
@@ -124,7 +130,7 @@ void lkdtm_READ_AFTER_FREE(void) 
	kfree(val);

}



void lkdtm_WRITE_BUDDY_AFTER_FREE(void)

static void lkdtm_WRITE_BUDDY_AFTER_FREE(void)

{

	unsigned long p = __get_free_page(GFP_KERNEL);

	if (!p) {
@@ -144,7 +150,7 @@ void lkdtm_WRITE_BUDDY_AFTER_FREE(void) 
	schedule();

}



void lkdtm_READ_BUDDY_AFTER_FREE(void)

static void lkdtm_READ_BUDDY_AFTER_FREE(void)

{

	unsigned long p = __get_free_page(GFP_KERNEL);

	int saw, *val;
@@ -181,7 +187,7 @@ void lkdtm_READ_BUDDY_AFTER_FREE(void) 
	kfree(val);

}



void lkdtm_SLAB_INIT_ON_ALLOC(void)

static void lkdtm_SLAB_INIT_ON_ALLOC(void)

{

	u8 *first;

	u8 *val;
@@ -213,7 +219,7 @@ void lkdtm_SLAB_INIT_ON_ALLOC(void) 
	kfree(val);

}



void lkdtm_BUDDY_INIT_ON_ALLOC(void)

static void lkdtm_BUDDY_INIT_ON_ALLOC(void)

{

	u8 *first;

	u8 *val;
@@ -246,7 +252,7 @@ void lkdtm_BUDDY_INIT_ON_ALLOC(void) 
	free_page((unsigned long)val);

}



void lkdtm_SLAB_FREE_DOUBLE(void)

static void lkdtm_SLAB_FREE_DOUBLE(void)

{

	int *val;
@@ -263,7 +269,7 @@ void lkdtm_SLAB_FREE_DOUBLE(void) 
	kmem_cache_free(double_free_cache, val);

}



void lkdtm_SLAB_FREE_CROSS(void)

static void lkdtm_SLAB_FREE_CROSS(void)

{

	int *val;
@@ -279,7 +285,7 @@ void lkdtm_SLAB_FREE_CROSS(void) 
	kmem_cache_free(b_cache, val);

}



void lkdtm_SLAB_FREE_PAGE(void)

static void lkdtm_SLAB_FREE_PAGE(void)

{

	unsigned long p = __get_free_page(GFP_KERNEL);
@@ -313,3 +319,22 @@ void __exit lkdtm_heap_exit(void) 
	kmem_cache_destroy(a_cache);

	kmem_cache_destroy(b_cache);

}



static struct crashtype crashtypes[] = {

	CRASHTYPE(SLAB_LINEAR_OVERFLOW),

	CRASHTYPE(VMALLOC_LINEAR_OVERFLOW),

	CRASHTYPE(WRITE_AFTER_FREE),

	CRASHTYPE(READ_AFTER_FREE),

	CRASHTYPE(WRITE_BUDDY_AFTER_FREE),

	CRASHTYPE(READ_BUDDY_AFTER_FREE),

	CRASHTYPE(SLAB_INIT_ON_ALLOC),

	CRASHTYPE(BUDDY_INIT_ON_ALLOC),

	CRASHTYPE(SLAB_FREE_DOUBLE),

	CRASHTYPE(SLAB_FREE_CROSS),

	CRASHTYPE(SLAB_FREE_PAGE),

};



struct crashtype_category heap_crashtypes = {

	.crashtypes = crashtypes,

	.len	    = ARRAY_SIZE(crashtypes),

};