Add a test that triggers stack writes across recursive calls,verifying detection at specific recursion depths.
Signed-off-by: Jinchao Wang <[email protected]> --- mm/kstackwatch/test.c | 29 ++++++++++++++++++++++++++++- 1 file changed, 28 insertions(+), 1 deletion(-) diff --git a/mm/kstackwatch/test.c b/mm/kstackwatch/test.c index 2b196f72ffd7..3e867d778e91 100644 --- a/mm/kstackwatch/test.c +++ b/mm/kstackwatch/test.c @@ -150,6 +150,27 @@ static void silent_corruption_test(void) silent_corruption_victim(i); } +/* + * Test Case 3: Recursive Call Corruption + * Test corruption detection at specified recursion depth + */ +static void recursive_corruption_test(int depth) +{ + u64 buffer[BUFFER_SIZE]; + + pr_info("recursive call at depth %d\n", depth); + pr_info("buffer 0x%lx\n", (unsigned long)buffer); + if (depth <= MAX_DEPTH) + recursive_corruption_test(depth + 1); + + buffer[0] = depth; + + /* make sure the compiler do not drop assign action */ + barrier_data(buffer); + + pr_info("returning from depth %d\n", depth); +} + static ssize_t test_proc_write(struct file *file, const char __user *buffer, size_t count, loff_t *pos) { @@ -181,6 +202,11 @@ static ssize_t test_proc_write(struct file *file, const char __user *buffer, pr_info("triggering silent corruption test\n"); silent_corruption_test(); break; + case 3: + pr_info("triggering recursive corruption test\n"); + /* depth start with 0 */ + recursive_corruption_test(0); + break; default: pr_err("Unknown test number %d\n", test_num); return -EINVAL; @@ -202,7 +228,8 @@ static ssize_t test_proc_read(struct file *file, char __user *buffer, "Usage:\n" " echo 'test0' > /proc/kstackwatch_test - Canary write test\n" " echo 'test1' > /proc/kstackwatch_test - Canary overflow test\n" - " echo 'test2' > /proc/kstackwatch_test - Silent corruption test\n"; + " echo 'test2' > /proc/kstackwatch_test - Silent corruption test\n" + " echo 'test3' > /proc/kstackwatch_test - Recursive corruption test\n"; return simple_read_from_buffer(buffer, count, pos, usage, strlen(usage)); -- 2.43.0
