Can you post the code of the simple program you used to reproduce the error? (including the .pb.h/.pb.cc or the .proto file)
On Thu, May 22, 2014 at 10:58 AM, <patrickbrosi...@googlemail.com> wrote: > Thank your very much for your answer! The result of > > GOOGLE_PROTOBUF_VERIFY_VERSION; > FeedMessage fm; > LOG(INFO) << fm.GetDescriptor()->DebugString(); > > in both applications is > > ==13935== Invalid read of size 8 > ==13935== at 0x510EFF2: > google::protobuf::DescriptorPool::FindFileByName(std::string const&) const > (in /usr/lib/x86_64-linux-gnu/libprotobuf.so.8.0.0) > ==13935== by 0x47F3F4: > transit_realtime::protobuf_AssignDesc_gtfs_2drealtime_2eproto() (in > /home/patrick/secure/repo/trajserver-internal2/build/trajhttpserv) > ==13935== by 0x50E22CF: > google::protobuf::internal::FunctionClosure0::Run() (in > /usr/lib/x86_64-linux-gnu/libprotobuf.so.8.0.0) > ==13935== by 0x50E24F0: google::protobuf::GoogleOnceInitImpl(long*, > google::protobuf::Closure*) (in > /usr/lib/x86_64-linux-gnu/libprotobuf.so.8.0.0) > ==13935== by 0x474464: transit_realtime::FeedMessage::GetMetadata() > const (in /home/patrick/secure/repo/trajserver-internal2/build/trajhttpserv) > ==13935== by 0x442D40: GtfsRealTimeReader::getTripUpdates() (in > /home/patrick/secure/repo/trajserver-internal2/build/trajhttpserv) > ==13935== by 0x4824AB: > updateRealtimeReaders(std::vector<GtfsRealTimeReader, > std::allocator<GtfsRealTimeReader> >*, unsigned int) (in > /home/patrick/secure/repo/trajserver-internal2/build/trajhttpserv) > ==13935== Address 0x0 is not stack'd, malloc'd or (recently) free'd > ==13935== > [22/05/2014 19:55:47,646579] FATAL: CRASH HANDLED; Application has crashed > due to [SIGSEGV] signal > > > Am Donnerstag, 22. Mai 2014 19:47:21 UTC+2 schrieb Feng Xiao: >> >> Can you try if the following code can produce any meaningful results? I >> suggest you try this once in your original binary and then create a simple >> program calling the following code only (and only linking the .proto file >> without anything else in your project). If both fail (segfault), it might >> be a bug in protobuf generated code. If only the former fails, the problem >> should be somewhere else in your project (memory corruption bugs most >> likely). >> >> LOG(INFO) << fm.GetDescriptor()->DebugString(); >> >> Note that you shouldn't change the generated code. It won't work. >> >> >> On Thu, May 22, 2014 at 9:28 AM, <patrick...@googlemail.com> wrote: >> >>> I am still experiencing this problem. Any help is highly appreciated, I >>> tried everything. >>> >>> The problem only occurs if bad data is fed to the parseFromString() >>> function. The following code crashes with a segmentation fault if >>> readBuffer contains bad data (currently, the content of >>> http://www.google.com). If readBuffer contains well-formed >>> GTFS-realtime data, everything works as expected: >>> >>> if (!(fm.ParseFromString(readBuffer))) { >>> LOG(WARNING) << "Failed to parse realtime GTFS."; >>> return; >>> } >>> >>> This is the line in the gtfs-realtime.pb.cc (in method >>> protobuf_AssignDesc_headers_2fprotobuf_2fgtfs_2drealtime_2eproto()) >>> that causes the crash: >>> >>> const ::google::protobuf::FileDescriptor* file = >>> ::google::protobuf::DescriptorPool::generated_ >>> pool()->FindFileByName( >>> "headers/protobuf/gtfs-realtime.proto"); >>> >>> For some reason, it tries to read the original .proto file if bad data >>> is received. I tried changing this line to an absolute path, but the >>> problem persists. The gtfs-realtime.proto file resides in headers/protobuf. >>> protoc is called like this: >>> >>> protoc -I=headers/protobuf --cpp_out=. headers/protobuf/gtfs- >>> realtime.proto >>> >>> I tried several locations for -cpp_out, but it didnt help. >>> >>> This is the valgrind output after the crash: >>> >>> ==4015== Invalid read of size 8 >>> ==4015== at 0x5108FF2: >>> google::protobuf::DescriptorPool::FindFileByName(std::string >>> const&) const (in /usr/lib/x86_64-linux-gnu/libprotobuf.so.8.0.0) >>> ==4015== by 0x47F3F4: transit_realtime::protobuf_ >>> AssignDesc_gtfs_2drealtime_2eproto() (in /home/patrick/repos/ >>> trajserver/trajhttpserv) >>> ==4015== by 0x50DC2CF: >>> google::protobuf::internal::FunctionClosure0::Run() >>> (in /usr/lib/x86_64-linux-gnu/libprotobuf.so.8.0.0) >>> ==4015== by 0x50DC4F0: google::protobuf::GoogleOnceInitImpl(long*, >>> google::protobuf::Closure*) (in /usr/lib/x86_64-linux-gnu/ >>> libprotobuf.so.8.0.0) >>> ==4015== by 0x474444: transit_realtime::FeedMessage::GetMetadata() >>> const (in /home/patrick/repos/trajserver/trajhttpserv) >>> ==4015== by 0x513FF6F: google::protobuf::Message::GetTypeName() >>> const (in /usr/lib/x86_64-linux-gnu/libprotobuf.so.8.0.0) >>> ==4015== by 0x50EB090: ??? (in /usr/lib/x86_64-linux-gnu/ >>> libprotobuf.so.8.0.0) >>> ==4015== by 0x50EB891: >>> google::protobuf::MessageLite::ParseFromString(std::string >>> const&) (in /usr/lib/x86_64-linux-gnu/libprotobuf.so.8.0.0) >>> ==4015== by 0x442E83: GtfsRealTimeReader::getTripUpdates() (in >>> /home/patrick/repos/trajserver/trajhttpserv) >>> ==4015== by 0x4824AB: >>> updateRealtimeReaders(std::vector<GtfsRealTimeReader, >>> std::allocator<GtfsRealTimeReader> >*, unsigned int) (in >>> /home/patrick/repos/trajserver/trajhttpserv) >>> ==4015== Address 0x0 is not stack'd, malloc'd or (recently) free'd >>> ==4015== >>> [22/05/2014 15:21:02,241645] FATAL: CRASH HANDLED; Application has >>> crashed due to [SIGSEGV] signal >>> >>> >>> Again, this crash happens every time I try to parse some random string >>> as a GTFS-realtime protobuf feed. >>> >>> I reproduced the segfault on three different machines: a Ubuntu 13.10 >>> machine with libprotoc 2.4.1, a Ubuntu 14.04 machine with libprotoc 2.5.0 >>> and a Debian machine with libprotoc 2.4.1. I tried different c++ version, >>> Ii tried -O1, -O2, -O3, I tried fixing the gtfs-realtime.pb.cc line by >>> hand, I played around with the protoc parameters, I compiled and installed >>> libprotoc 2.5.0 by hand on all 3 machines, I tried parsing the feed from a >>> stream and from a string, I created an application that only reads >>> http://www.google.com and feeds it to parseFromString() function - the >>> behaviour is always exactly the same: no problem on well-formed data, >>> segfault on bad data. >>> >>> I am using the original gtfs-realtime.proto file from the GTFS realtime >>> page. >>> >>> Anyone? >>> >>> >>> Am Freitag, 2. Mai 2014 15:29:48 UTC+2 schrieb patrick...@googlemail.com >>> : >>> >>>> Hi, >>>> >>>> I am using a straightforward C++ client to fetch GTFS-realtime feeds. >>>> Feeds are read into a string with libcurl and than parsed: >>>> >>>> GOOGLE_PROTOBUF_VERIFY_VERSION; >>>> FeedMessage fm; >>>> >>>> /** fetching realtime feed with libcurl into readBuffer **/ >>>> >>>> if (!fm.ParseFromString(readBuffer)) { // this line crashes >>>> LOG(ERROR) << "Failed to parse realtime GTFS."; >>>> return; >>>> } >>>> >>>> I experience random segfault crashes during parsing. All of them oocure >>>> while parsing a very specific feed. The segfault is caused by >>>> >>>> google::protobuf::DescriptorPool::FindFileByName >>>> >>>> Backtrace: >>>> >>>> Program received signal SIGSEGV, Segmentation fault. >>>> #0 0x00007ffff7901f3e in >>>> google::protobuf::DescriptorPool::FindFileByName(std::string >>>> const&) const () from /usr/lib/libprotobuf.so.7 >>>> #1 0x000000000047e045 in transit_realtime::protobuf_Ass >>>> ignDesc_headers_2fprotobuf_2fgtfs_2drealtime_2eproto() () at >>>> headers/protobuf/gtfs-realtime.pb.cc:80 >>>> #2 0x00007ffff7683400 in pthread_once () >>>> at ../nptl/sysdeps/unix/sysv/linux/x86_64/pthread_once.S:104 >>>> #3 0x0000000000471593 in transit_realtime::FeedMessage::GetMetadata() >>>> const >>>> () at /usr/include/google/protobuf/stubs/once.h:115 >>>> #4 0x00007ffff7932274 in google::protobuf::Message::GetTypeName() >>>> const () >>>> from /usr/lib/libprotobuf.so.7 >>>> #5 0x00007ffff78e2f17 in ?? () from /usr/lib/libprotobuf.so.7 >>>> #6 0x00007ffff78e3714 in >>>> google::protobuf::MessageLite::ParseFromString(std::string >>>> const&) () from /usr/lib/libprotobuf.so.7 >>>> >>>> >>>> Since the segfaults are _always_ caused by the same feed, I strongly >>>> suspect that it is bad data that causes the crash. The random nature of the >>>> crashes could be explained by the feed returning a bad message every few >>>> few hours. Nevertheless, for bad data, ParseFromString() should return >>>> false, and not crash completely. >>>> >>>> I am using g++ 4.8.1 with -O3 -g -std=c++0x >>>> protoc --version returns "libprotoc 2.4.1" >>>> >>>> Thanks for any help :) >>>> >>>> >>>> >>>> >>>> >>>> >>>> -- >>> You received this message because you are subscribed to the Google >>> Groups "Protocol Buffers" group. >>> To unsubscribe from this group and stop receiving emails from it, send >>> an email to protobuf+u...@googlegroups.com. >>> To post to this group, send email to prot...@googlegroups.com. >>> >>> Visit this group at http://groups.google.com/group/protobuf. >>> For more options, visit https://groups.google.com/d/optout. >>> >> >> -- > You received this message because you are subscribed to the Google Groups > "Protocol Buffers" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to protobuf+unsubscr...@googlegroups.com. > To post to this group, send email to protobuf@googlegroups.com. > Visit this group at http://groups.google.com/group/protobuf. > For more options, visit https://groups.google.com/d/optout. > -- You received this message because you are subscribed to the Google Groups "Protocol Buffers" group. 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