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Hi,<br>
Rafaël Carré wrote:
<blockquote cite="mid:4A96AEDB.4070504@gmail.com" type="cite">
<blockquote type="cite">
<pre wrap="">0x000000006a598c54: mov (%rbx),%rcx
</pre>
</blockquote>
<pre wrap=""><!---->
you can show the registers with "info registers" in gdb, so we can see
for example if it is a NULL dereference
</pre>
</blockquote>
Here's gdb output with info registers, sorry there was no backtrace
because gdb doesn't show any.<br>
<br>
Program received signal SIGSEGV, Segmentation fault.<br>
[Switching to thread 9004.0x23ac]<br>
0x000000006a598c54 in ?? ()<br>
(gdb) warning: Invalid parameter passed to C runtime function.<br>
<br>
disass $pc-30 $pc+30<br>
Dump of assembler code from 0x6a598c36 to 0x6a598c72:<br>
0x000000006a598c36: add %al,0x88be(%rax)<br>
0x000000006a598c3c: add %al,(%rax)<br>
0x000000006a598c3e: movq $0x0,0x18(%r13)<br>
0x000000006a598c46: movl $0x0,0x20(%r13)<br>
0x000000006a598c4e: jne 0x6a598f33<br>
0x000000006a598c54: mov (%rbx),%rcx<br>
0x000000006a598c57: test %rcx,%rcx<br>
0x000000006a598c5a: je 0x6a598c66<br>
0x000000006a598c5c: cmpl $0x2,0x8(%rcx)<br>
0x000000006a598c60: je 0x6a599120<br>
0x000000006a598c66: mov %r13,(%rbx)<br>
0x000000006a598c69: add $0x8,%rdi<br>
0x000000006a598c6d: cmp $0x1,%r15d<br>
0x000000006a598c71: mov $0x1,%r12d<br>
End of assembler dump.<br>
(gdb) info registers<br>
rax 0x0 0<br>
rcx 0x0 0<br>
rdx 0x0 0<br>
rbx 0x17afc0 1552320<br>
rsp 0xec0fa90 247528080<br>
rbp 0xec0faf0 247528176<br>
rsi 0xec0fbc0 247528384<br>
rdi 0x273de08 41147912<br>
r8 0x0 0<br>
r9 0x0 0<br>
r10 0x0 0<br>
r11 0x0 0<br>
r12 0x273e320 41149216<br>
r13 0x9d 157<br>
r14 0x273b3e0 41137120<br>
r15 0x0 0<br>
rip 0x6a598c54 0x6a598c54<br>
eflags 0x10246 [ PF ZF IF RF ]<br>
cs 0x33 51<br>
ss 0x2b 43<br>
ds 0x2b 43<br>
es 0x2b 43<br>
fs 0x53 83<br>
gs 0x2b 43<br>
<br>
<br>
Thanks.<br>
Regards.<br>
<br>
<br>
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