Bug#970460: qemu-user: trashes argv[0] breaking multi-call binaries

16.09.2020 20:15, John Paul Adrian Glaubitz wrote:
> 
>> On Sep 16, 2020, at 6:57 PM, Thorsten Glaser <[email protected]> wrote:
>>
>> I’m attaching a test program that does the following:
>>
>> • if argv[1] is "-" it just outputs argv[0] and argv[1]
>> • otherwise it also execve(2)s argv[1] with its argv[0] set to "meow"
> 
> That’s been fixed upstream and can be configured with the qemu-binfmt.sh script and the option “preserved=yes”.

Where it's been fixed? current git version of scripts/qemu-binfmt-conf.sh
does not have 'preserved' option, and if the P flag is set when registering
binfmt, the kernel will _prepend_ additional argv[0] element which is not
expected by current linux-user/main.c code (so the tst.c example will be
running with 3 args, not 2).

Thanks,

/mjt