Commit 7640e770 authored by Beau Belgrave's avatar Beau Belgrave Committed by Steven Rostedt (Google)
Browse files

user_events: Add self-test for validator boundaries 

Tests to ensure validator boundary cases are working correctly within
close and far bounds. Ensures __data_loc and __rel_loc strings are
null terminated and within range. Ensures min size checks work as
expected.

Link: https://lkml.kernel.org/r/20220118204326.2169-11-beaub@linux.microsoft.com



Acked-by: default avatarMasami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: default avatarBeau Belgrave <beaub@linux.microsoft.com>
Signed-off-by: default avatarSteven Rostedt (Google) <rostedt@goodmis.org>
parent 3a616389

tools/testing/selftests/user_events/ftrace_test.c

+65 −0
Original line number Diff line number Diff line
@@ -309,6 +309,71 @@ TEST_F(user, write_fault) { 
	ASSERT_EQ(0, munmap(anon, l));

}



TEST_F(user, write_validator) {

	struct user_reg reg = {0};

	struct iovec io[3];

	int loc, bytes;

	char data[8];

	int before = 0, after = 0;



	reg.size = sizeof(reg);

	reg.name_args = (__u64)"__test_event __rel_loc char[] data";



	/* Register should work */

	ASSERT_EQ(0, ioctl(self->data_fd, DIAG_IOCSREG, &reg));

	ASSERT_EQ(0, reg.write_index);

	ASSERT_NE(0, reg.status_index);



	io[0].iov_base = &reg.write_index;

	io[0].iov_len = sizeof(reg.write_index);

	io[1].iov_base = &loc;

	io[1].iov_len = sizeof(loc);

	io[2].iov_base = data;

	bytes = snprintf(data, sizeof(data), "Test") + 1;

	io[2].iov_len = bytes;



	/* Undersized write should fail */

	ASSERT_EQ(-1, writev(self->data_fd, (const struct iovec *)io, 1));

	ASSERT_EQ(EINVAL, errno);



	/* Enable event */

	self->enable_fd = open(enable_file, O_RDWR);

	ASSERT_NE(-1, write(self->enable_fd, "1", sizeof("1")))



	/* Full in-bounds write should work */

	before = trace_bytes();

	loc = DYN_LOC(0, bytes);

	ASSERT_NE(-1, writev(self->data_fd, (const struct iovec *)io, 3));

	after = trace_bytes();

	ASSERT_GT(after, before);



	/* Out of bounds write should fault (offset way out) */

	loc = DYN_LOC(1024, bytes);

	ASSERT_EQ(-1, writev(self->data_fd, (const struct iovec *)io, 3));

	ASSERT_EQ(EFAULT, errno);



	/* Out of bounds write should fault (offset 1 byte out) */

	loc = DYN_LOC(1, bytes);

	ASSERT_EQ(-1, writev(self->data_fd, (const struct iovec *)io, 3));

	ASSERT_EQ(EFAULT, errno);



	/* Out of bounds write should fault (size way out) */

	loc = DYN_LOC(0, bytes + 1024);

	ASSERT_EQ(-1, writev(self->data_fd, (const struct iovec *)io, 3));

	ASSERT_EQ(EFAULT, errno);



	/* Out of bounds write should fault (size 1 byte out) */

	loc = DYN_LOC(0, bytes + 1);

	ASSERT_EQ(-1, writev(self->data_fd, (const struct iovec *)io, 3));

	ASSERT_EQ(EFAULT, errno);



	/* Non-Null should fault */

	memset(data, 'A', sizeof(data));

	loc = DYN_LOC(0, bytes);

	ASSERT_EQ(-1, writev(self->data_fd, (const struct iovec *)io, 3));

	ASSERT_EQ(EFAULT, errno);

}



TEST_F(user, print_fmt) {

	int ret;