Re: [PATCH] elf: sanitize objname in _dl_signal_error

[Jiangfeng Xiao <xiaojiangfeng@huawei.com>]

On 2024/4/1 21:50, Adhemerval Zanella Netto wrote:


> How did you trigger this issue, either from user provided ABI (dlfcn.h)
> or some some internal usage (if any)? If this is a user-visible issue
> it will require a bug report and a reproducer.
> 

Thanks for your reply.


The following are my reproduction cases:

```
#include <dlfcn.h>

int main(void)
{
	(void)dlopen("not_exist.so", -1);

	return 0;
}

```

However, this case cannot be reproduced in a common environment.

I reproduced this issue in the arm32 environment.
Glibc in the environment is compiled using the Clang compiler.
The glibc version is 2.34. (The patches that supports Clang
compilation has been applied to this version)

I have not figured out why the lcatch variable
in the _dl_signal_error function is null.
As a result, the exception branch
fatal_error(0, NULL, NULL, NULL, "invalid mode parameter")
is executed.
Maybe my Clang compiler's compilation parameters
are not configured properly.

I can then be sure that if glibc is compiled by the GCC compiler,
it should not trigger this issue.

I don't think the glibc mainline branch will trigger this problem
because glibc has not officially promised to support Clang.
So I think I'd rather not submit a bug report first.