From: Florian Weimer <fweimer@redhat.com>
To: Jacob Kroon <jacob.kroon@gmail.com>
Cc: Jacob Kroon via Gdb <gdb@sourceware.org>
Subject: Re: Debugging ld.so in gdb
Date: Fri, 04 Feb 2022 17:09:10 +0100 [thread overview]
Message-ID: <87h79eobq1.fsf@oldenburg.str.redhat.com> (raw)
In-Reply-To: <dd662ef3-e7b3-b566-4342-607c820f2528@gmail.com> (Jacob Kroon's message of "Fri, 4 Feb 2022 15:27:15 +0100")
* Jacob Kroon:
> On 2/4/22 15:22, Florian Weimer wrote:
>> * Jacob Kroon:
>>
>>> This is what I get, following the instructions above:
>>>
>>>> 171966 0x00007ffff7fd85a0 <dfs_traversal+80>: mov 0x0(%r13),%rax
>>>> 171967 0x00007ffff7fd85a4 <dfs_traversal+84>: lea -0x8(%rax),%rdx
>>>> 171968 0x00007ffff7fd85a8 <dfs_traversal+88>: mov %rdx,0x0(%r13)
>>>> 171969 0x00007ffff7fd85ac <dfs_traversal+92>: mov %rbp,-0x8(%rax)
>>>> 171970 0x00007ffff7fd85b0 <dfs_traversal+96>: add $0x8,%rsp
>>>> 171971 0x00007ffff7fd85b4 <dfs_traversal+100>: pop %rbx
>>>> 171972 0x00007ffff7fd85b5 <dfs_traversal+101>: pop %rbp
>>>> 171973 0x00007ffff7fd85b6 <dfs_traversal+102>: pop %r12
>>>> 171974 0x00007ffff7fd85b8 <dfs_traversal+104>: pop %r13
>>>> 171975 0x00007ffff7fd85ba <dfs_traversal+106>: ret
>>>
>>> Does that make sense ? Any other information I can provide. This is with
>>> glibc-2.34-24.fc35.x86_64, Fedora 35.
>>
>> This doesn't really make sense. There's probably some GDB option to get
>> a longer trace.
>>
>> If it is crashing at the RET, it means that either code has been mapped
>> over, or the stack has been corrupted. At the crash site, what does
>>
>> print *(void**)$rsp
>>
>> print?
>>
>
> $2 = (void *) 0x7ffff7d31b70
>
>> disassemble *(void**)$rsp
>>
>> could also be interesting.
>>
>
> "No function contains specified address"
>
> Let me see if I can find some gdb option to get a longer trace.
Looks like the code at that address has been unmapped (or the link map
is at least gone from a GDB perspective). Maybe you can see what was at
the address before using “info files”?
Thanks,
Florian
next prev parent reply other threads:[~2022-02-04 16:09 UTC|newest]
Thread overview: 24+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-02-04 13:45 Jacob Kroon
2022-02-04 13:58 ` Florian Weimer
2022-02-04 14:09 ` Jacob Kroon
2022-02-04 14:22 ` Florian Weimer
2022-02-04 14:27 ` Jacob Kroon
2022-02-04 16:09 ` Florian Weimer [this message]
2022-02-04 16:53 ` Jacob Kroon
2022-02-04 17:04 ` Florian Weimer
2022-02-04 17:11 ` Jacob Kroon
2022-02-04 17:15 ` Florian Weimer
2022-02-07 8:36 ` Jacob Kroon
2022-02-07 11:46 ` Jacob Kroon
2022-02-07 11:55 ` Florian Weimer
2022-02-07 12:15 ` Jacob Kroon
2022-02-07 12:27 ` Florian Weimer
2022-02-07 12:32 ` Jacob Kroon
2022-02-07 13:39 ` Jacob Kroon
2022-02-07 13:45 ` Jacob Kroon
2022-02-07 13:53 ` Adhemerval Zanella
2022-02-07 13:54 ` Jacob Kroon
2022-02-07 14:07 ` Florian Weimer
2022-02-07 16:28 ` Florian Weimer
2022-02-07 17:04 ` Jacob Kroon
2022-02-04 14:45 ` Jacob Kroon
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