I have not yet found the solution on internet so i ask it here. Never had this problem before it was always doing fine, so i don't know what changed. I'm using gdb peda but the problem stays the same with normal gdb.
I'm loading a program called "main" in gdb : gdb main
Then I get the functions name : info functions
0x000000000000162f main
(I removed extra symbols, it actually shows more symbols)
Then I disassamble the main : disas main
0x0000000000001708 <+217>: movzx eax,BYTE PTR [rbp+rax*1-0x70]
0x000000000000170d <+222>: cmp dl,al
0x000000000000170f <+224>: je 0x1718 <main+233>
(Same here I only show a small part)
Since I'm interested in watching what is being compared I want to set a breakpoint there b *0x170d
And when I run it it says
Cannot insert breakpoint 1.
Cannot access memory at address 0x170d
So I tried to set up a breakpoint at address 0x0 but I get the same error.
Running it first and then disassembling it gives the following :
0x0000555555555708 <+217>: movzx eax,BYTE PTR [rbp+rax*1-0x70]
0x000055555555570d <+222>: cmp dl,al
0x000055555555570f <+224>: je 0x555555555718 <main+233>
On another computer it's working fine I just set the breakpoint at the address it shows. I usually use ghidra and set the breakpoint at the addresses shown in ghidra's disassembler. I read that it was a problem with gdb not mapping memory but i have not found a working solution.
to kind of resolve it what I'm doing is that I run it first then read memory when it's running I take the address of the instruction where I want to set the breakpoint and rerun it.
