The SMTP app layer used a thread local data structure for the mpm in
reply parsing, but it only used a pmq. The MpmThreadCtx was actually
global. Until now this wasn't really noticed because non of the mpm's
used the thread ctx.
Hyperscan does use it however.
This patch creates a new structure SMTPThreadCtx, which contains both
the pmq and the mpm thread ctx. It's passed directly to the reply
parsing function instead of storing a pointer to it in the SMTPState.
Additionally fix a small memory leak warning wrt the smtp global mpm
state.
Make the file storage use the streaming buffer API.
As the individual file chunks were not needed by themselves, this
approach uses a chunkless implementation.
This patch fixes the following leak:
Direct leak of 9982880 byte(s) in 2902 object(s) allocated from:
#0 0x4c253b in malloc ??:?
#1 0x10c39ac in MimeDecInitParser /home/victor/qa/buildbot/donkey/z600fuzz/Private/src/util-decode-mime.c:2379
#2 0x6a0f91 in SMTPProcessRequest /home/victor/qa/buildbot/donkey/z600fuzz/Private/src/app-layer-smtp.c:1085
#3 0x697658 in SMTPParse /home/victor/qa/buildbot/donkey/z600fuzz/Private/src/app-layer-smtp.c:1185
#4 0x68fa7a in SMTPParseClientRecord /home/victor/qa/buildbot/donkey/z600fuzz/Private/src/app-layer-smtp.c:1208
#5 0x6561c5 in AppLayerParserParse /home/victor/qa/buildbot/donkey/z600fuzz/Private/src/app-layer-parser.c:908
#6 0x53dc2e in AppLayerHandleTCPData /home/victor/qa/buildbot/donkey/z600fuzz/Private/src/app-layer.c:444
#7 0xf8e0af in DoReassemble /home/victor/qa/buildbot/donkey/z600fuzz/Private/src/stream-tcp-reassemble.c:2635
#8 0xf8c3f8 in StreamTcpReassembleAppLayer /home/victor/qa/buildbot/donkey/z600fuzz/Private/src/stream-tcp-reassemble.c:3028
#9 0xf94267 in StreamTcpReassembleHandleSegmentUpdateACK /home/victor/qa/buildbot/donkey/z600fuzz/Private/src/stream-tcp-reassemble.c:3404
#10 0xf9643d in StreamTcpReassembleHandleSegment /home/victor/qa/buildbot/donkey/z600fuzz/Private/src/stream-tcp-reassemble.c:3432
#11 0xf578b4 in HandleEstablishedPacketToClient /home/victor/qa/buildbot/donkey/z600fuzz/Private/src/stream-tcp.c:2245
#12 0xeea3c7 in StreamTcpPacketStateEstablished /home/victor/qa/buildbot/donkey/z600fuzz/Private/src/stream-tcp.c:2489
#13 0xec1d38 in StreamTcpPacket /home/victor/qa/buildbot/donkey/z600fuzz/Private/src/stream-tcp.c:4568
#14 0xeb0e16 in StreamTcp /home/victor/qa/buildbot/donkey/z600fuzz/Private/src/stream-tcp.c:5064
#15 0xff52a4 in TmThreadsSlotVarRun /home/victor/qa/buildbot/donkey/z600fuzz/Private/src/tm-threads.c:130
#16 0xffdad1 in TmThreadsSlotVar /home/victor/qa/buildbot/donkey/z600fuzz/Private/src/tm-threads.c:474
#17 0x7f7cd678d181 in start_thread /build/buildd/eglibc-2.19/nptl/pthread_create.c:312 (discriminator 2)
We come to this case when a SMTP session contains at least 2 mails
and then the ending of the first is not correctly detected. In that
case, switching to a new tx seems a good solution. This way we still
have partial logging.
If SMTP session is weird then we may reach a state where a field
like MAIL FROM is seen as duplicated.
Valgrind output is:
30 bytes in 1 blocks are definitely lost in loss record 96 of 399
at 0x4C29C0F: malloc (in /usr/lib/valgrind/vgpreload_memcheck-amd64-linux.so)
by 0x4A5803: SMTPParseCommandWithParam (app-layer-smtp.c:996)
by 0x4A4DCE: SMTPParseCommandMAILFROM (app-layer-smtp.c:1016)
by 0x4A3F55: SMTPProcessRequest (app-layer-smtp.c:1127)
by 0x4A1F8C: SMTPParse (app-layer-smtp.c:1191)
by 0x493AD7: SMTPParseClientRecord (app-layer-smtp.c:1214)
by 0x4878A6: AppLayerParserParse (app-layer-parser.c:908)
by 0x42384E: AppLayerHandleTCPData (app-layer.c:444)
by 0x8D7EAD: DoReassemble (stream-tcp-reassemble.c:2635)
by 0x8D795F: StreamTcpReassembleAppLayer (stream-tcp-reassemble.c:3028)
by 0x8D8BE0: StreamTcpReassembleHandleSegmentUpdateACK (stream-tcp-reassemble.c:3404)
by 0x8D8F6E: StreamTcpReassembleHandleSegment (stream-tcp-reassemble.c:3432)
If a boundary was longer than 254 bytes a stack overflow would result
in mime decoding.
Ticket #1449
Reported-by: Kostya Kortchinsky of the Google Security Team
Victor Julien
Justin Viiret
Mats Klepsland
Eric Leblond
Giuseppe Longo
David Abarbanel
Anoop Saldanha