Goal is to attach to a running process, get the process mappings, identify heap and examine. Within gdb on Linux it's quite comfortable to do info proc map. I have some struggle with this on FreeBSD.
When I attach to a running program and do the (more generic) maintenance info sections:
.. I dont see it.
I guess I could use procstat -v <PID> which does provide better information but I was not able to tell "this is heap":
I'd like to have a better way of identifying it than "somewhere after the bss section".
I tried to find the memory map (virtual memory layout) of 32b FreeBSD system, something official. What I found was that the memory is divided into classic 1:4 ratio where the upper chunk is reserved for the kernel.
I'd like to know if there's better way of identifying this though.
When I attach to a running program and do the (more generic) maintenance info sections:
Code:
(gdb) main info sec
Exec file:
`/local/test/test', file type elf32-i386-freebsd.
0x8048134->0x8048149 at 0x00000134: .interp ALLOC LOAD READONLY DATA HAS_CONTENTS
0x804814c->0x8048164 at 0x0000014c: .note.ABI-tag ALLOC LOAD READONLY DATA HAS_CONTENTS
0x8048164->0x80482a0 at 0x00000164: .hash ALLOC LOAD READONLY DATA HAS_CONTENTS
0x80482a0->0x8048520 at 0x000002a0: .dynsym ALLOC LOAD READONLY DATA HAS_CONTENTS
0x8048520->0x804867a at 0x00000520: .dynstr ALLOC LOAD READONLY DATA HAS_CONTENTS
...I guess I could use procstat -v <PID> which does provide better information but I was not able to tell "this is heap":
Code:
procstat -v 80900
PID START END PRT RES PRES REF SHD FL TP PATH
80900 0x8048000 0x804a000 r-x 2 0 1 0 CN-- vn /local/test/test
80900 0x804a000 0x8400000 rw- 1 0 1 0 ---- df
80900 0x2804a000 0x2805f000 r-x 20 0 1 0 C--- vn /libexec/ld-elf.so.1
80900 0x2805f000 0x28060000 rw- 1 0 1 0 C--- vn /libexec/ld-elf.so.1
80900 0x28060000 0x2806a000 rw- 10 0 1 0 ---- df
80900 0x2806a000 0x28080000 r-x 22 0 1 0 C--- vn /lib/libthr.so.3
80900 0x28080000 0x28082000 rw- 2 0 1 0 C--- vn /lib/libthr.so.3
80900 0x28082000 0x2808a000 rw- 7 0 1 0 ---- df
80900 0x2808a000 0x28197000 r-x 236 0 66 31 CN-- vn /lib/libc.so.7
80900 0x28197000 0x2819e000 rw- 7 0 1 0 C--- vn /lib/libc.so.7
80900 0x2819e000 0x281c8000 rw- 14 0 2 0 ---- df
80900 0x28400000 0x28800000 rw- 11 0 2 0 ---- df
80900 0xbf9df000 0xbf9ff000 rwx 2 0 1 0 ---D df
80900 0xbf9ff000 0xbfa00000 --- 0 0 0 0 ---- --
80900 0xbfbe0000 0xbfc00000 rwx 3 0 1 0 ---D dfI'd like to have a better way of identifying it than "somewhere after the bss section".
I tried to find the memory map (virtual memory layout) of 32b FreeBSD system, something official. What I found was that the memory is divided into classic 1:4 ratio where the upper chunk is reserved for the kernel.
I'd like to know if there's better way of identifying this though.
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