[PATCH] posix: Fix posix_spawnpi to not execute invalid binaries in non compat mode (BZ#23264)

[Florian Weimer]

On 06/06/2018 08:26 PM, Adhemerval Zanella wrote:
> 
> 
> On 06/06/2018 15:20, Florian Weimer wrote:
>> On 06/06/2018 08:11 PM, Adhemerval Zanella wrote:
>>> Current posix_spawnp implementation wrongly tries to execute invalid
>>> binaries (for instance script without shebang) as a shell script in
>>> non compat mode.  It was a regression introduced by
>>> 9ff72da471a509a8c19791efe469f47fa6977410 when __spawni started to use
>>> __execvpe instead of __execve (glibc __execvpe try to execute ENOEXEC
>>> as shell script regardless).
>>>
>>> This patch fixes it by using an internal symbol (__execvpex) with the
>>> faulty semantic (since compat mode is handled by spawni.c itself).
>>
>> Why doesn't this need a new compatibility symbol, similar to the previously attempted change?
> 
> Should we handle regressions in such way? My intention is to backport it
> to previous versions as well.

Hmm, right, it's a regression.

So this leads to the question why we need to keep the old compat 
behavior.  Maybe we can just alias the two symbol versions to a single 
implementation?  Is it really necessary to preserve the old script 
execution behavior?

Thanks,
Florian