New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Jump to bottom

http2: fix session memory accounting after pausing #30684

Closed

mikelehen wants to merge 1 commit into nodejs:master from mikelehen:mikelehen/fix-http2-session-memory-accounting-leak

Commits on Nov 27, 2019

http2: fix session memory accounting after pausing

The ability to pause input processing was added in 8a4a193 but
introduced a session memory accounting mismatch leading to potential
NGHTTP2_ENHANCE_YOUR_CALM errors.

After pausing
(https://github.com/nodejs/node/blob/f36331c1bfa4c4c202346b05dc3bd672f653e4df/src/node_http2.cc#L871),
the early return on line 873 skips the
DecrementCurrentSessionMemory(stream_buf_.len) call below (line 878).

When we later finished processing the input chunk
(https://github.com/nodejs/node/blob/f36331c1bfa4c4c202346b05dc3bd672f653e4df/src/node_http2.cc#L1858),
we were calling DecrementCurrentSessionMemory(stream_buf_offset_) [line
1875] which was a no-op since we just set stream_buf_offset_ to 0 [line
1873].

The correct amount to decrement by is still stream_buf_.len, since
that's the amount we skipped previously (line 878).

Fixes: nodejs#29223
Refs: nodejs@164ac5b

Michael Lehenbauer committed Nov 27, 2019