Debugging ld.so in gdb

[Jacob Kroon <jacob.kroon@gmail.com>]

Hi,

Since a week or two I have started to see a segfault on my updated
Fedora 35 system. I suspect the segfault is related to a recent glibc
update.

The segfault I see happens when I run the following:

$ ldd ./mylib.so

I narrowed it down to running:

$ LD_TRACE_LOADED_OBJECTS=1 /lib64/ld-linux-x86-64.so.2 ./mylib.so

"coredumpctl info" gives me:

> Stack trace of thread 143567:
> #0  0x00007ff428f73590 n/a (n/a + 0x0)
> #1  0x00007ff428f8af0f _dl_map_object_deps (/usr/lib64/ld-linux-x86-64.so.2 + 0x3f0f)
> #2  0x00007ff428fa6970 dl_main (/usr/lib64/ld-linux-x86-64.so.2 + 0x1f970)
> #3  0x00007ff428fa2c7c _dl_sysdep_start (/usr/lib64/ld-linux-x86-64.so.2 + 0x1bc7c)
> #4  0x00007ff428fa4678 _dl_start_final (/usr/lib64/ld-linux-x86-64.so.2 + 0x1d678)
> #5  0x00007ff428fa36a8 _start (/usr/lib64/ld-linux-x86-64.so.2 + 0x1c6a8)

but inspecting in gdb using "coredumpctl debug" doesn't give me any sane
backtrace.

The .so is part of a Yocto build. If I copy the file out from its build
directory to $HOME and run ldd on it, then there is no crash. So I
suspect RUNPATH is involved somehow since it contains $ORIGIN.

Any ideas of what I can do to investigate further ?

Regards Jacob