Re: [PATCH] gdb: Fix use-after-free when an objfile has no symbols to load

[Guinevere Larsen <guinevere@redhat.com>]

On 12/6/24 2:35 PM, Simon Marchi wrote:
>
> On 2024-12-05 08:19, Guinevere Larsen wrote:
>> The recent commit <HASH> moved an initialization of an objfile_holder in
>> syms_from_objfile_1 much earlier in the function, to better deal with
>> when GDB is unable to read the objfile format.
>>
>> However, there is an early exit from syms_from_objfile_1 when the
>> objfile can be understood, but has no symbols. That was not releasing
>> the objfile_holder, so the objfile was being unlinked from the program
>> space, but the process of reading the objfile was being continued,
>> leading to use-after-frees flagged by the Address Sanitizer.
>>
>> This commit fixes that UAF by making the objfile_holder release the
>> objfile right before the early exit.
>>
>> This commit also changes the test gdb.base/dump.exp since that was the
>> original test that flagged the UAF, but at the end of the test the
>> generated files were being deleted, meaning we couldn't redo the test
>> manually after teh fact. That final deletion was removed
> teh -> the
>
> Approved-By: Simon Marchi <simon.marchi@efficios.com>
>
> Thanks,
>
> Simon
>
Thanks for the review, pushed!

-- 
Cheers,
Guinevere Larsen
She/Her/Hers