@@ -28,8 +28,8 @@ TEST(unshare_EMFILE)
int fd;
ssize_t n, n2;
static char buf[512], buf2[512];
- struct rlimit rlimit;
int nr_open;
+ int bits_per_long = sizeof(long) * 8;
fd = open("/proc/sys/fs/nr_open", O_RDWR);
ASSERT_GE(fd, 0);
@@ -40,24 +40,8 @@ TEST(unshare_EMFILE)
ASSERT_EQ(sscanf(buf, "%d", &nr_open), 1);
- ASSERT_EQ(0, getrlimit(RLIMIT_NOFILE, &rlimit));
-
- /* bump fs.nr_open */
- n2 = sprintf(buf2, "%d\n", nr_open + 1024);
- lseek(fd, 0, SEEK_SET);
- write(fd, buf2, n2);
-
- /* bump ulimit -n */
- rlimit.rlim_cur = nr_open + 1024;
- rlimit.rlim_max = nr_open + 1024;
- EXPECT_EQ(0, setrlimit(RLIMIT_NOFILE, &rlimit)) {
- lseek(fd, 0, SEEK_SET);
- write(fd, buf, n);
- exit(EXIT_FAILURE);
- }
-
- /* get a descriptor past the old fs.nr_open */
- EXPECT_GE(dup2(2, nr_open + 64), 0) {
+ /* get a descriptor >= bits_per_long */
+ EXPECT_GE(dup2(2, bits_per_long+1), 0) {
lseek(fd, 0, SEEK_SET);
write(fd, buf, n);
exit(EXIT_FAILURE);
@@ -74,15 +58,21 @@ TEST(unshare_EMFILE)
if (pid == 0) {
int err;
- /* restore fs.nr_open */
+ /* set nr_open == bits_per_long */
+ n2 = sprintf(buf2, "%d\n", bits_per_long);
lseek(fd, 0, SEEK_SET);
- write(fd, buf, n);
+ write(fd, buf2, n2);
+
/* ... and now unshare(CLONE_FILES) must fail with EMFILE */
err = unshare(CLONE_FILES);
EXPECT_EQ(err, -1)
exit(EXIT_FAILURE);
EXPECT_EQ(errno, EMFILE)
exit(EXIT_FAILURE);
+
+ /* restore fs.nr_open */
+ lseek(fd, 0, SEEK_SET);
+ write(fd, buf, n);
exit(EXIT_SUCCESS);
}
dup2(2, nr_open+64) may cause ENOMEM error, change to dup2(2, bits_per_long +1) and set nr_open to bits_per_long to avoid ENOMEM. Signed-off-by: lufei <lufei@uniontech.com> --- tools/testing/selftests/core/unshare_test.c | 32 +++++++-------------- 1 file changed, 11 insertions(+), 21 deletions(-)