darling-xnu/tests/lockf_EOF_77264182.c
2023-05-16 21:41:14 -07:00

57 lines
1.6 KiB
C

#include <fcntl.h>
#include <sys/fcntl.h>
#include <darwintest.h>
#include <darwintest_utils.h>
T_GLOBAL_META(
T_META_NAMESPACE("xnu.ipc"),
T_META_RADAR_COMPONENT_NAME("xnu"),
T_META_RADAR_COMPONENT_VERSION("IPC"),
T_META_OWNER("jonathan_w_adams"),
T_META_RUN_CONCURRENTLY(TRUE));
/*
* See rdar://77264182: xnu's lockf implementation had trouble
* with l_len = 0 (e.g. go to EOF) being treated differently
* than (l_start + l_len - 1) == OFF_MAX, even though they are
* effectively the same thing. ~25 loops of this test was enough
* to get an Intel mac into an infinite loop in the kernel.
*/
T_DECL(lockf_EOF_77264182,
"try to stress out lockf requests around OFF_MAX/EOF",
T_META_CHECK_LEAKS(false))
{
const char *dir = dt_tmpdir();
int fd;
T_ASSERT_POSIX_SUCCESS(chdir(dir), "chdir(%s)", dir);
T_ASSERT_POSIX_SUCCESS((fd = open("lockf_EOF_test", O_CREAT | O_RDWR, 0666)), "open(lockf_EOF_test)");
/*
* At each loop, we do:
* write lock [OFF_MAX - loop, EOF)
* unlock [OFF_MAX - loop, OFF_MAX)
* write lock [OFF_MAX - loop - 1, OFF_MAX)
*/
int loops;
for (loops = 0; loops < 100; loops++) {
struct flock fl = {
.l_start = OFF_MAX - loops,
.l_len = 0,
.l_pid = getpid(),
.l_type = F_WRLCK,
.l_whence = SEEK_SET
};
T_ASSERT_POSIX_SUCCESS(fcntl(fd, F_SETLK, &fl), "wrlock");
fl.l_len = OFF_MAX - fl.l_start + 1;
fl.l_type = F_UNLCK;
T_ASSERT_POSIX_SUCCESS(fcntl(fd, F_SETLK, &fl), "unlock");
fl.l_start--;
fl.l_len++;
fl.l_type = F_WRLCK;
T_ASSERT_POSIX_SUCCESS(fcntl(fd, F_SETLK, &fl), "wrlock 2");
}
T_PASS("did %d loops", loops);
}