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: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Beau Belgrave <beaub@linux.microsoft.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
This commit is contained in:
Beau Belgrave 2022-01-18 12:43:24 -08:00 committed by Steven Rostedt (Google)
parent 3a6163893a
commit 7640e77035

View File

@ -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;