mm/kasan/report_generic.c

Source file repositories/reference/linux-study-clean/mm/kasan/report_generic.c

File Facts

System
Linux kernel
Corpus path
mm/kasan/report_generic.c
Extension
.c
Size
10505 bytes
Lines
400
Domain
Core OS
Bucket
Memory Management
Inferred role
Core OS: exported/initcall integration point
Status
integration implementation candidate

Why This File Exists

Core operating-system implementation surface: boot, tasks, memory, VFS, syscall-facing interfaces, synchronization, credentials, and isolation.

Dependency Surface

Detected Declarations

Annotated Snippet

if (tok_len + 1 > max_tok_len) {
			pr_err("internal error: frame description too long: %s\n",
			       *frame_descr);
			return false;
		}

		/* Copy token (+ 1 byte for '\0'). */
		strscpy(token, *frame_descr, tok_len + 1);
	}

	/* Advance frame_descr past separator. */
	*frame_descr = sep + 1;

	if (value != NULL && kstrtoul(token, 10, value)) {
		pr_err("internal error: not a valid number: %s\n", token);
		return false;
	}

	return true;
}

static void print_decoded_frame_descr(const char *frame_descr)
{
	/*
	 * We need to parse the following string:
	 *    "n alloc_1 alloc_2 ... alloc_n"
	 * where alloc_i looks like
	 *    "offset size len name"
	 * or "offset size len name:line".
	 */

	char token[64];
	unsigned long num_objects;

	if (!tokenize_frame_descr(&frame_descr, token, sizeof(token),
				  &num_objects))
		return;

	pr_err("\n");
	pr_err("This frame has %lu %s:\n", num_objects,
	       num_objects == 1 ? "object" : "objects");

	while (num_objects--) {
		unsigned long offset;
		unsigned long size;

		/* access offset */
		if (!tokenize_frame_descr(&frame_descr, token, sizeof(token),
					  &offset))
			return;
		/* access size */
		if (!tokenize_frame_descr(&frame_descr, token, sizeof(token),
					  &size))
			return;
		/* name length (unused) */
		if (!tokenize_frame_descr(&frame_descr, NULL, 0, NULL))
			return;
		/* object name */
		if (!tokenize_frame_descr(&frame_descr, token, sizeof(token),
					  NULL))
			return;

		/* Strip line number; without filename it's not very helpful. */
		strreplace(token, ':', '\0');

		/* Finally, print object information. */
		pr_err(" [%lu, %lu) '%s'", offset, offset + size, token);
	}
}

/* Returns true only if the address is on the current task's stack. */
static bool __must_check get_address_stack_frame_info(const void *addr,
						      unsigned long *offset,
						      const char **frame_descr,
						      const void **frame_pc)
{
	unsigned long aligned_addr;
	unsigned long mem_ptr;
	const u8 *shadow_bottom;
	const u8 *shadow_ptr;
	const unsigned long *frame;

	BUILD_BUG_ON(IS_ENABLED(CONFIG_STACK_GROWSUP));

	aligned_addr = round_down((unsigned long)addr, sizeof(long));
	mem_ptr = round_down(aligned_addr, KASAN_GRANULE_SIZE);
	shadow_ptr = kasan_mem_to_shadow((void *)aligned_addr);
	shadow_bottom = kasan_mem_to_shadow(end_of_stack(current));

	while (shadow_ptr >= shadow_bottom && *shadow_ptr != KASAN_STACK_LEFT) {

Annotation

Implementation Notes