Edge: Fix flv edge crash when http unmount. v6.0.154 v7.0.13 #4166
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
winlinvip
changed the title
winlinvip
force-pushed
the
bugfix/flv-edge
branch
from
674ed15
to
078c6f6
Compare
winlinvip
changed the title
winlinvip
added a commit
that referenced
this pull request
Aug 31, 2024
Edge FLV is not working because it is stuck in an infinite loop waiting.
Previously, there was no need to wait for exit since resources were not
being cleaned up. Now, since resources need to be cleaned up, it must
wait for all active connections to exit, which causes this issue.
To reproduce the issue, start SRS edge, run the bellow command and press
`CTRL+C` to stop the request:
```bash
curl http://localhost:8080/live/livestream.flv -v >/dev/null
```
It will cause edge to fetch stream from origin, and free the consumer
when client quit. When `SrsLiveStream::do_serve_http` return, it will
free the consumer:
```cpp
srs_error_t SrsLiveStream::do_serve_http(ISrsHttpResponseWriter* w, ISrsHttpMessage* r) {
SrsUniquePtr<SrsLiveConsumer> consumer(consumer_raw);
```
Keep in mind that in this moment, the stream is alive, because only set
to not alive after this function return:
```cpp
alive_viewers_++;
err = do_serve_http(w, r); // Free 'this' alive stream.
alive_viewers_--; // Crash here, because 'this' is freed.
```
When freeing the consumer, it will cause the source to unpublish and
attempt to free the HTTP handler, which ultimately waits for the stream
not to be alive:
```cpp
SrsLiveConsumer::~SrsLiveConsumer() {
source_->on_consumer_destroy(this);
void SrsLiveSource::on_consumer_destroy(SrsLiveConsumer* consumer) {
if (consumers.empty()) {
play_edge->on_all_client_stop();
void SrsLiveSource::on_unpublish() {
handler->on_unpublish(req);
void SrsHttpStreamServer::http_unmount(SrsRequest* r) {
if (stream->entry) stream->entry->enabled = false;
for (; i < 1024; i++) {
if (!cache->alive() && !stream->alive()) {
break;
}
srs_usleep(100 * SRS_UTIME_MILLISECONDS);
}
```
After 120 seconds, it will free the stream and cause SRS to crash
because the stream is still active. In order to track this potential
issue, also add an important warning log:
```cpp
srs_warn("http: try to free a alive stream, cache=%d, stream=%d", cache->alive(), stream->alive());
```
SRS may crash if got this log.
---------
Co-authored-by: Jacob Su <suzp1984@gmail.com>
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Edge FLV is not working because it is stuck in an infinite loop waiting. Previously, there was no need to wait for exit since resources were not being cleaned up. Now, since resources need to be cleaned up, it must wait for all active connections to exit, which causes this issue.
To reproduce the issue, start SRS edge, run the bellow command and press
CTRL+Cto stop the request:curl http://localhost:8080/live/livestream.flv -v >/dev/nullIt will cause edge to fetch stream from origin, and free the consumer when client quit. When
SrsLiveStream::do_serve_httpreturn, it will free the consumer:Keep in mind that in this moment, the stream is alive, because only set to not alive after this function return:
alive_viewers_++; err = do_serve_http(w, r); // Free 'this' alive stream. alive_viewers_--; // Crash here, because 'this' is freed.When freeing the consumer, it will cause the source to unpublish and attempt to free the HTTP handler, which ultimately waits for the stream not to be alive:
After 120 seconds, it will free the stream and cause SRS to crash because the stream is still active. In order to track this potential issue, also add an important warning log:
SRS may crash if got this log.
Co-authored-by: Jacob Su suzp1984@gmail.com