m3m3m4n / modbus-fuzz-note Goto Github PK

Hello, I am using your modified aflnet-modbus to fuzz the modbus program. But encountered some difficulties:

I compiled and used the afl-fuzz main program according to the installation method you gave. The command used is as follows:

../../afl-fuzz -d -i in -o out -N tcp://127.0.0.1/1502 -P MODBUSTCP -m none -D 10000 -q 3 -s 3 -Q -R -K . /test-server

However, after execution of this command, afl-fuzz will crash after a random time, and the error message is: segmentation fault.

I used gdb to parse the core dump file. gdb shows that the error occurs in

memcpy(m->mdata, &out_buf[regions[i].start_byte], len); in afl-fuzz.c.

I tried again and again and this error still exists. I don't understand what went wrong. The available evidence seems to point to a memory issue, but I still can't pinpoint the problem and don't know how to fix it. Do you have any good suggestions or ideas? Looking forward to your reply