diff options
| -rw-r--r-- | kernel/fork.c | 23 | ||||
| -rw-r--r-- | tools/testing/selftests/pidfd/pidfd_info_test.c | 13 |
2 files changed, 27 insertions, 9 deletions
diff --git a/kernel/fork.c b/kernel/fork.c index c4b26cd8998b..4a2080b968c8 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -2108,10 +2108,27 @@ static int __pidfd_prepare(struct pid *pid, unsigned int flags, struct file **re */ int pidfd_prepare(struct pid *pid, unsigned int flags, struct file **ret) { - bool thread = flags & PIDFD_THREAD; + int err = 0; - if (!pid || !pid_has_task(pid, thread ? PIDTYPE_PID : PIDTYPE_TGID)) - return -EINVAL; + if (!(flags & PIDFD_THREAD)) { + /* + * If this is struct pid isn't used as a thread-group + * leader pid but the caller requested to create a + * thread-group leader pidfd then report ENOENT to the + * caller as a hint. + */ + if (!pid_has_task(pid, PIDTYPE_TGID)) + err = -ENOENT; + } + + /* + * If this wasn't a thread-group leader struct pid or the task + * got reaped in the meantime report -ESRCH to userspace. + */ + if (!pid_has_task(pid, PIDTYPE_PID)) + err = -ESRCH; + if (err) + return err; return __pidfd_prepare(pid, flags, ret); } diff --git a/tools/testing/selftests/pidfd/pidfd_info_test.c b/tools/testing/selftests/pidfd/pidfd_info_test.c index 1758a1b0457b..a0eb6e81eaa2 100644 --- a/tools/testing/selftests/pidfd/pidfd_info_test.c +++ b/tools/testing/selftests/pidfd/pidfd_info_test.c @@ -299,6 +299,7 @@ TEST_F(pidfd_info, thread_group) /* Opening a thread as a thread-group leader must fail. */ pidfd_thread = sys_pidfd_open(pid_thread, 0); ASSERT_LT(pidfd_thread, 0); + ASSERT_EQ(errno, ENOENT); /* Opening a thread as a PIDFD_THREAD must succeed. */ pidfd_thread = sys_pidfd_open(pid_thread, PIDFD_THREAD); @@ -362,9 +363,9 @@ TEST_F(pidfd_info, thread_group) ASSERT_EQ(ioctl(pidfd_leader, PIDFD_GET_INFO, &info), 0); ASSERT_FALSE(!!(info.mask & PIDFD_INFO_CREDS)); ASSERT_TRUE(!!(info.mask & PIDFD_INFO_EXIT)); - /* The thread-group leader exited successfully. Only the specific thread was SIGKILLed. */ - ASSERT_TRUE(WIFEXITED(info.exit_code)); - ASSERT_EQ(WEXITSTATUS(info.exit_code), 0); + /* Even though the thread-group exited successfully it will still report the group exit code. */ + ASSERT_TRUE(WIFSIGNALED(info.exit_code)); + ASSERT_EQ(WTERMSIG(info.exit_code), SIGKILL); /* * Retrieve exit information for the thread-group leader via the @@ -375,9 +376,9 @@ TEST_F(pidfd_info, thread_group) ASSERT_FALSE(!!(info2.mask & PIDFD_INFO_CREDS)); ASSERT_TRUE(!!(info2.mask & PIDFD_INFO_EXIT)); - /* The thread-group leader exited successfully. Only the specific thread was SIGKILLed. */ - ASSERT_TRUE(WIFEXITED(info2.exit_code)); - ASSERT_EQ(WEXITSTATUS(info2.exit_code), 0); + /* Even though the thread-group exited successfully it will still report the group exit code. */ + ASSERT_TRUE(WIFSIGNALED(info2.exit_code)); + ASSERT_EQ(WTERMSIG(info2.exit_code), SIGKILL); /* Retrieve exit information for the thread. */ info.mask = PIDFD_INFO_CGROUPID | PIDFD_INFO_EXIT; |