lkdtm/stackleak: Make the test more verbose (01c0514e) · Commits · 戴 / test

drivers/misc/lkdtm/stackleak.c

+17 −8

Original line number	Diff line number	Diff line
		@@ -16,6 +16,7 @@ void lkdtm_STACKLEAK_ERASING(void)
		unsigned long *sp, left, found, i;
		const unsigned long check_depth =
		STACKLEAK_SEARCH_DEPTH / sizeof(unsigned long);
		bool test_failed = false;

		/*
		* For the details about the alignment of the poison values, see
		@@ -34,7 +35,8 @@ void lkdtm_STACKLEAK_ERASING(void)
		left--;
		} else {
		pr_err("FAIL: not enough stack space for the test\n");
		return;
		test_failed = true;
		goto end;
		}

		pr_info("checking unused part of the thread stack (%lu bytes)...\n",
		@@ -52,22 +54,29 @@ void lkdtm_STACKLEAK_ERASING(void)
		}

		if (found <= check_depth) {
		pr_err("FAIL: thread stack is not erased (checked %lu bytes)\n",
		pr_err("FAIL: the erased part is not found (checked %lu bytes)\n",
		i * sizeof(unsigned long));
		return;
		test_failed = true;
		goto end;
		}

		pr_info("first %lu bytes are unpoisoned\n",
		pr_info("the erased part begins after %lu not poisoned bytes\n",
		(i - found) * sizeof(unsigned long));

		/* The rest of thread stack should be erased */
		for (; i < left; i++) {
		if (*(sp - i) != STACKLEAK_POISON) {
		pr_err("FAIL: thread stack is NOT properly erased\n");
		return;
		pr_err("FAIL: bad value number %lu in the erased part: 0x%lx\n",
		i, *(sp - i));
		test_failed = true;
		}
		}

		end:
		if (test_failed) {
		pr_err("FAIL: the thread stack is NOT properly erased\n");
		dump_stack();
		} else {
		pr_info("OK: the rest of the thread stack is properly erased\n");
		return;
		}
		}