tree bd17bc9decca96d211d6b97e2eec6bede728980a
parent 8f5699bda16c96c06a71d6515d1a73bbfbc68235
author Amaury Denoyelle <adenoyelle@haproxy.com> 1671544036 +0100
committer Amaury Denoyelle <adenoyelle@haproxy.com> 1671609484 +0100

BUG/MEDIUM: mux-quic: fix double delete from qcc.opening_list

qcs instances for bidirectional streams are inserted in
<qcc.opening_list>. It is removed from the list once a full HTTP request
has been parsed. This is required to implement http-request timeout.

In case a stream is deleted before receiving full HTTP request, it also
must be removed from <qcc.opening_list>. This was not the case on first
implementation but has been fixed by the following patch :
  641a65ff3cccd394eed49378c6ccdb8ba0a101a7
  BUG/MINOR: mux-quic: remove qcs from opening-list on free

This means that now a stream can be deleted from the list in two
different functions. Sadly, as LIST_DELETE was used in both cases,
nothing prevented a double-deletion from the list, even though
LIST_INLIST was used. Both calls are replaced with LIST_DEL_INIT which
is idempotent.

This bug causes memory corruption which results in most cases in a
segfault, most of times outside of mux-quic code itself. It has been
found first by gabrieltz who reported it on the github issue #1903. Big
thanks to him for his testing.

This bug also causes failures on several 'M' transfer testcase of QUIC
interop-runner. The s2n-quic client is particularly useful in this case
as segfaults triggers were most of the times on the LIST_DELETE
operation itself. This is probably due to its encapsulating of HEADERS
frame with fin bit delayed in a following empty STREAM frame.

This must be backported wherever the above patch is, up to 2.6.