diff options
| author | Eric W. Biederman <ebiederm@xmission.com> | 2020-06-25 17:23:22 -0500 |
|---|---|---|
| committer | Eric W. Biederman <ebiederm@xmission.com> | 2020-07-07 11:58:57 -0500 |
| commit | e80eb1dc868bc1ed93602389d54b27f170ca770c (patch) | |
| tree | 79fa3fd78b5dcdde8b08eb4d7f0d4c7b14a46ad9 /net/bpfilter | |
| parent | 38fd525a4c61e7ecdc9ad4dcbf7b767d0a007962 (diff) | |
bpfilter: Take advantage of the facilities of struct pid
Instead of relying on the exit_umh cleanup callback use the fact a
struct pid can be tested to see if a process still exists, and that
struct pid has a wait queue that notifies when the process dies.
v1: https://lkml.kernel.org/r/87h7uydlu9.fsf_-_@x220.int.ebiederm.org
v2: https://lkml.kernel.org/r/874kqt4owu.fsf_-_@x220.int.ebiederm.org
Link: https://lkml.kernel.org/r/20200702164140.4468-14-ebiederm@xmission.com
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Tested-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Diffstat (limited to 'net/bpfilter')
| -rw-r--r-- | net/bpfilter/bpfilter_kern.c | 15 |
1 files changed, 5 insertions, 10 deletions
diff --git a/net/bpfilter/bpfilter_kern.c b/net/bpfilter/bpfilter_kern.c index 08ea77c2b137..9616fb7defeb 100644 --- a/net/bpfilter/bpfilter_kern.c +++ b/net/bpfilter/bpfilter_kern.c @@ -18,10 +18,11 @@ static void shutdown_umh(void) struct umd_info *info = &bpfilter_ops.info; struct pid *tgid = info->tgid; - if (bpfilter_ops.stop) - return; - - kill_pid(tgid, SIGKILL, 1); + if (tgid) { + kill_pid(tgid, SIGKILL, 1); + wait_event(tgid->wait_pidfd, thread_group_exited(tgid)); + bpfilter_umh_cleanup(info); + } } static void __stop_umh(void) @@ -77,7 +78,6 @@ static int start_umh(void) err = fork_usermode_driver(&bpfilter_ops.info); if (err) return err; - bpfilter_ops.stop = false; pr_info("Loaded bpfilter_umh pid %d\n", pid_nr(bpfilter_ops.info.tgid)); /* health check that usermode process started correctly */ @@ -100,16 +100,11 @@ static int __init load_umh(void) return err; mutex_lock(&bpfilter_ops.lock); - if (!bpfilter_ops.stop) { - err = -EFAULT; - goto out; - } err = start_umh(); if (!err && IS_ENABLED(CONFIG_INET)) { bpfilter_ops.sockopt = &__bpfilter_process_sockopt; bpfilter_ops.start = &start_umh; } -out: mutex_unlock(&bpfilter_ops.lock); if (err) umd_unload_blob(&bpfilter_ops.info); |