Wireshark-commits: [Wireshark-commits] master-1.12 047c4c0: packet-vnc.c: Improve re-assembly.
URL: https://code.wireshark.org/review/gitweb?p=wireshark.git;a=commit;h=047c4c07551ceb5c8b9d2a97dbe7aa657f743d5d
Submitter: Bill Meier (wmeier@xxxxxxxxxxx)
Changed: branch: master-1.12
Repository: wireshark
Commits:
047c4c0 by Bill Meier (wmeier@xxxxxxxxxxx):
packet-vnc.c: Improve re-assembly.
Essentially:
When more data is needed to continue dissecting a PDU, use
DESEGMENT_ONE_MORE_SEGMENT instead of repeatedly requesting
additional bytes (for one or a few more fields).
- Improves the efficiency of the dissection;
- Prevents 'one-pass' tshark dissection from redissecting
the PDU repeatedly many, many times with each time dissecting
the PDU with one or a few more additional fields.
This generated *lots* of (repeated) output since a reassembled
VNC PDU can contain many fields (each of short length).
- (A comment in packet-tcp.c states, in effect, that repeatedly
requesting a specific amount of more bytes to dissect a PDU
will "break reassembly" although I note that the reassembly did
seem to work (in-efficiently)).
Note: Although this patch improves the handling of reassembly, the
dissector has significant issues. For example. see Bug #5366.
I expect this fixes the Bug #10134 issue: "Cannot allocate memory";
Before the fix, 'tshark -nVxr' for the input file generated trees with
multiple hundreds of thousands of entries and generated reassembled
PDUs consisting of many, many small fragments.
Change-Id: I970037c346fbaa4bffa5726fd5bee5f69396eabf
Reviewed-on: https://code.wireshark.org/review/2471
Reviewed-by: Bill Meier <wmeier@xxxxxxxxxxx>
(cherry picked from commit 728e5a1ab3e2614ec83a6af43a52742cf0f5df01)
Reviewed-on: https://code.wireshark.org/review/2821
Actions performed:
from 71cb629 catapult,irda: Fix ASAN crashes due to buffer underrun
adds 047c4c0 packet-vnc.c: Improve re-assembly.
Summary of changes:
epan/dissectors/packet-vnc.c | 23 ++++++++++++++++-------
1 file changed, 16 insertions(+), 7 deletions(-)
