Report memory mapping to GDB client

[ttimasdf]

Is your feature request related to a problem? Please describe.

gdb command info proc mapping returns empty.

Describe the solution you'd like

There seems to be a stub here that may make it easier to implement this feature. maybe make a little bit change to ql.mem.show_mapinfo() could emulate a procmaps file?

https://github.com/qilingframework/qiling/blob/67d35579a78390cf975d81a96c08e361f086ba9e/qiling/debugger/gdbserver/gdbserver.py#L631-L632

I've never played with gdb protocol. I'll send a PR if I figure it out 😅

[xwings]

the thing is we dont have /proc in qiling. To be honest, i still not too sure if we need to emulate that.

or we should figure out why do we need /proc and how we can emulate it.

[ttimasdf]

At least providing memory mapping information is friendly to debuggers.

I have a hacky solution here, https://github.com/ttimasdf/qiling/commit/5142844d9715328462f4917b4e80e40a35938711 . But I'm not sure it's good enough for PR. This patch should be used along with #325 or gdb will crash because of that bug.

Test case:

qltool run -f examples/rootfs/arm_linux/bin/arm_hello_static \
  --rootfs examples/rootfs/arm_linux --gdb 127.0.0.1:9999

Before:

After:

PS: I'm trying to add this feature because it's essential for a gdb plugin(ret-sync) to work (also stops gef from complaining), very personal...

[xwings]

i guess u should just parse show_mapinfo. and rearrange in gdb.

this way u dont have to touch ql.os.memory?

maybe u can update and trow in a PR ?

[ttimasdf]

I'm getting to update this fix. There's a problem. How to get the return value of show_mapinfo? It's printed to console/log file. So one way or another it seems we need to modify ql.os.memory. IMHO i'd prefer to add another method to make it reusable.

https://github.com/qilingframework/qiling/blob/078996ce2dbe61c3da0b9b352634876d0e38be0f/qiling/os/memory.py#L119-L136

[xwings]

If you look at the code, show_mapinfo() just parse ql.mem.map_info()

So you can just parse ql.mem.map_info()

[zi0Black]

@ttimasdf a PR would be super nice 💯.

[xwings]

Will you be able to try the latest version of Qiling and see if you still face same issue. There is lots of rework since 2020. Feel free to open a new issue if you have any similar problem.