diff options
author | chris.zn <chris.zn@antfin.com> | 2019-06-20 15:19:05 +0800 |
---|---|---|
committer | chris.zn <chris.zn@antfin.com> | 2019-06-24 15:49:53 +0800 |
commit | f957fb23cf68e72084c7b50569242a07997f96bc (patch) | |
tree | 65451f6c2c5c2c87a70d8638614071b971aa6cbc /test/syscalls | |
parent | 7e49515696f628a41ed63199570d25dfbe9d8848 (diff) |
Return ENOENT when reading /proc/{pid}/task of an exited process
There will be a deadloop when we use getdents to read /proc/{pid}/task
of an exited process
Like this:
Process A is running
Process B: open /proc/{pid of A}/task
Process A exits
Process B: getdents /proc/{pid of A}/task
Then, process B will fall into deadloop, and return "." and ".."
in loops and never ends.
This patch returns ENOENT when use getdents to read /proc/{pid}/task
if the process is just exited.
Signed-off-by: chris.zn <chris.zn@antfin.com>
Diffstat (limited to 'test/syscalls')
-rw-r--r-- | test/syscalls/linux/proc.cc | 19 |
1 files changed, 19 insertions, 0 deletions
diff --git a/test/syscalls/linux/proc.cc b/test/syscalls/linux/proc.cc index 924b98e3a..2177665c8 100644 --- a/test/syscalls/linux/proc.cc +++ b/test/syscalls/linux/proc.cc @@ -1908,6 +1908,25 @@ void CheckDuplicatesRecursively(std::string path) { TEST(Proc, NoDuplicates) { CheckDuplicatesRecursively("/proc"); } +TEST(Proc, Getdents) { + int child_pid = fork(); + ASSERT_GE(child_pid, 0); + if (child_pid == 0) { + while(1){ + sleep(100); + } + } + ASSERT_THAT(child_pid, SyscallSucceeds()); + char name[100]; + char buf[1024]; + int fd; + sprintf(name, "/proc/%d/task", child_pid); + fd = open(name, O_RDONLY | O_DIRECTORY); + ASSERT_THAT(kill(child_pid, SIGKILL), SyscallSucceeds()); + ASSERT_THAT(waitpid(child_pid, NULL, 0), SyscallSucceedsWithValue(child_pid)); + ASSERT_THAT(syscall(SYS_getdents, fd, buf, 1024), SyscallFailsWithErrno(ENOENT)); +} + // Most /proc/PID files are owned by the task user with SUID_DUMP_USER. TEST(ProcPid, UserDumpableOwner) { int before; |