[TS-733] segfault in mime_hdr_set_accelerators_and_presence_bits

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Won't Fix
• Affects Version/s: 2.0.1
• Component/s: MIME
• Labels: MIME segfault

Environment

X6240 AMD64 Debian Lenny (2.6.26) 64G of Ram.

• Assignee: Unassigned
• Reporter: Ricky Chan
• Created: 08/Apr/11 09:08
• Updated: 19/Aug/11 01:19
• Resolved: 30/May/11 01:45

Description

We are seeing segfault and I have now put back unstripped binaries so I can get line numbers are frame traces.

Below is the trace, although GDB claims it's line 482, I believe it's now actually there (a short int comparison won't crash it). My interest is the fact that m_wks_idx is 67 which is larger than the MAX amount of slots which I believe is 16 (0 - 15) right?

I got this segfault 6 times this morning, and it appears from the same client too.
I'm thinking of patching the code to make sure m_wks_idx isn't > MAX_FIELD_SLOTNUM_MAX for now.

#0 ink_stack_trace_dump (sighandler_frame=2) at ink_stack_trace.cc:66
66 fp = (void **) (*fp);
(gdb) bt
#0 ink_stack_trace_dump (sighandler_frame=2) at ink_stack_trace.cc:66
#1 0x0000000000502f8a in signal_handler (sig=<value optimized out>) at signals.cc:332
#2 <signal handler called>
#3 mime_hdr_field_detach (mh=0x2aaab46c1298, field=0x2aaab46c1390, detach_all_dups=false) at MIME.cc:482
#4 0x0000000000601e8e in mime_hdr_field_delete (heap=0x2aaab46c11e0, mh=0x2aaab46c1298, field=0x2aaab46c1390, delete_all_dups=true) at MIME.cc:1737
#5 0x000000000056cee9 in HttpTransact::set_headers_for_cache_write (s=0x2aaaba56d8b0, cache_info=0x2aaaba56d948, request=0x2aaaba56df90,
response=0x2aaaba56dfc8) at ../../iocore/cache/../../proxy/http2/../hdrs/MIME.h:1071
#6 0x000000000056ec29 in HttpTransact::handle_cache_operation_on_forward_server_response (s=0x2aaaba56d8b0) at HttpTransact.cc:5270
#7 0x000000000056ff99 in HttpTransact::handle_forward_server_connection_open (s=0x2aaaba56d8b0) at HttpTransact.cc:4732
#8 0x0000000000572370 in HttpTransact::handle_response_from_server (s=0x2aaaba56d8b0) at HttpTransact.cc:4255
#9 0x0000000000578a5d in HttpTransact::HandleResponse (s=0x2aaaba56d8b0) at HttpTransact.cc:3937
#10 0x0000000000534485 in HttpSM::call_transact_and_set_next_state (this=0x2aaaba56d830, f=0x2aaab46c1390) at HttpSM.cc:7190
#11 0x0000000000549aa0 in HttpSM::state_read_server_response_header (this=0x2aaaba56d830, event=<value optimized out>, data=0x2232e28) at HttpSM.cc:535
#12 0x0000000000547e3b in HttpSM::main_handler (this=0x2aaaba56d830, event=100, data=0x2232e28) at HttpSM.cc:2683
#13 0x00000000006c19f7 in read_from_net (nh=0x2aaaac950098, vc=0x2232d50, thread=<value optimized out>) at ../../iocore/eventsystem/I_Continuation.h:147
#14 0x00000000006b9452 in NetHandler::mainNetEvent (this=0x2aaaac950098, event=<value optimized out>, e=0xfa9130) at UnixNet.cc:292
#15 0x00000000006e3614 in EThread::process_event (this=0x2aaaac94f010, e=0xfa9130, calling_code=5) at I_Continuation.h:147
#16 0x00000000006e3e50 in EThread::execute (this=0x2aaaac94f010) at UnixEThread.cc:249
#17 0x00000000006e1a72 in spawn_thread_internal (a=0xf93270) at Thread.cc:85
#18 0x00002abbb5d7efc7 in start_thread () from /lib/libpthread.so.0
#19 0x00002abbb74f064d in clone () from /lib/libc.so.6
#20 0x0000000000000000 in ?? ()
(gdb) frame 3
#3 mime_hdr_field_detach (mh=0x2aaab46c1298, field=0x2aaab46c1390, detach_all_dups=false) at MIME.cc:482
warning: Source file is more recent than executable.
482 if (field->m_wks_idx < 0)
(gdb) p *field
$1 =

{ m_ptr_name = 0x19618e4 "Via1.1 AKmdrL2CacheBC10.telecom.co.nzCache-Controlmax-stale=0Via1.1 AKmdrL2CacheBC10.telecom.co.nzX-BlueCoat-ViaB8C344C089BFFBD7Client-ip210.55.215.151X-Forwarded-For210.55.215.151http10.244.132.255om"..., m_ptr_value = 0x19618e7 "1.1 AKmdrL2CacheBC10.telecom.co.nzCache-Controlmax-stale=0Via1.1 AKmdrL2CacheBC10.telecom.co.nzX-BlueCoat-ViaB8C344C089BFFBD7Client-ip210.55.215.151X-Forwarded-For210.55.215.151http10.244.132.255om0yo"..., m_next_dup = 0xffffffffb46c87f0, m_wks_idx = 67, m_len_name = 3, m_len_value = 34, m_n_v_raw_printable = 0 '\0', m_n_v_raw_printable_pad = 4 '\004', m_readiness = 2 '\002', m_flags = 1 '\001'}

Issue Links

• is related to: TS-729 Seg faults within HttpTransactHeaders::insert_via_header_in_request