On Fri, Nov 30, 2012 at 12:08:53PM +0100, Dieter Bloms wrote:
Hi Werner,
--snip-- 25 cString tComponent::ToString(void) 26 { 27 char buffer[256]; 28 snprintf(buffer, sizeof(buffer), "%X %02X %s %s", stream, type, language, description ? description : ""); 29 return buffer; 30 } 31 32 bool tComponent::FromString(const char *s) 33 { 34 unsigned int Stream, Type; 35 description = NULL; 36 int n = sscanf(s, "%X %02X %7s %as[^\n]", &Stream, &Type, language, &description); // 7 = MAXLANGCODE2 - 1 37 esyslog("dbloms: "%X" "%02X" "%7s" "%s"", Stream, Type, language, description); 38 39 if (n != 4 || isempty(description)) { 40 free(description); 41 description = NULL; 42 } 43 stream = Stream; 44 type = Type; 45 return n >= 3; 46 } --snip--
and get a core dump with this:
--snip-- vdrservernew:/tmp# gdb --core /tmp/core /usr/local/bin/vdr GNU gdb (GDB) 7.5 Copyright (C) 2012 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later http://gnu.org/licenses/gpl.html This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. Type "show copying" and "show warranty" for details. This GDB was configured as "x86_64-unknown-linux-gnu". For bug reporting instructions, please see: http://www.gnu.org/software/gdb/bugs/... Reading symbols from /usr/local/bin/vdr...done. [New LWP 8986] [New LWP 8985] [New LWP 8987] [Thread debugging using libthread_db enabled] Using host libthread_db library "/lib/libthread_db.so.1". Core was generated by `/usr/local/bin/vdr --config=/etc/vdr --epgfile=/tmp/epg.data --grab=/dev/shm --'. Program terminated with signal 11, Segmentation fault. #0 0x00006b2476b263b3 in strnlen () from /lib/libc.so.0.9.32 (gdb) bt #0 0x00006b2476b263b3 in strnlen () from /lib/libc.so.0.9.32 #1 0x00006b2476b1ff56 in ?? () from /lib/libc.so.0.9.32 #2 0x00006b2476b1d5dc in vsnprintf () from /lib/libc.so.0.9.32 #3 0x00006b2476b14c29 in vsyslog () from /lib/libc.so.0.9.32 #4 0x000000000052e510 in syslog_with_tid (priority=3, format=0x551ab8 "dbloms: "%X" "%02X" "%7s" "%s"") at tools.c:40 #5 0x00000000004a1e4e in FromString (s=<optimized out>, this=0x3dabc20) at epg.c:37 #6 cComponents::SetComponent (this=<optimized out>, Index=<optimized out>, s=s@entry=0x3daaaa2 "1 01 deu 4:3") at epg.c:84 #7 0x00000000004a4163 in cEvent::Parse (this=0x3d9f4d0, s=<optimized out>) at epg.c:498 #8 0x00000000004e9f16 in cRecordingInfo::Read (this=0x3da8640, f=f@entry=0x3d9f840) at recording.c:468 #9 0x00000000004eb553 in cRecording::cRecording (this=0x3da05c0, FileName=0x3d8aa7c "Sex_and_the_City_2/2012-11-19.20.10.27-0.rec") at recording.c:723 #10 0x00000000004ecf21 in cRecordings::ScanVideoDir (this=0x7fe880 <Recordings>, DirName=0x3d9d4c0 "/remote/vdr/Sex_and_the_City_2", Foreground=false, LinkLevel=0) at recording.c:1165 #11 0x00000000004ed39c in cRecordings::ScanVideoDir (this=0x7fe880 <Recordings>, DirName=0x3d83a20 "/remote/vdr", Foreground=false, LinkLevel=0) at recording.c:1180 #12 0x00000000005269be in cThread::StartThread (Thread=0x7fe8a0 <Recordings+32>) at thread.c:262 #13 0x00006b247844a406 in start_thread () from /lib/libpthread.so.0.9.32 #14 0x00006b2478442885 in clone () from /lib/libpthread.so.0.9.32 #15 0x0000000000000000 in ?? () (gdb) --snip--
Maybe some more checks are required as if n != 4 this could be that one of the variables are not used and therefore not initialized.
Before sscanf() this could be a `memset(language, 0, sizeof(language));' or more simple a `*language = 0;' depending on the type of language. Also the code
if (n != 4 || isempty(description)) { free(description); description = NULL; }
could become
if (n != 4 || isempty(description)) { if (description) free(description); description = NULL; }
as well as the line
esyslog("dbloms: "%X" "%02X" "%7s" "%s"", Stream, Type, language, description);
may look like
esyslog("dbloms: "%X" "%02X" "%7s" "%s"", Stream, Type, language, description ? description : "");
Werner