Re: access(2) shouldn't be used with test(1)

[Linda Walsh]

What are you saying it should return, because I get correct results
on linux:

sudo sh -c 'test -x start_trans; echo $?'
1
sudo bash -c 'test -x start_trans; echo $?'  
1

Are you saying that access on BSD, when
passed (filename "X_OK") returns "true" for superuser even
when the file isn't executable?

Sounds like a bug to me....   if a file isn't executable, I don't care
how "super" you are -- permission won't make a text file executable!
;-)

Or isn't that what BSD is sorta saying?




Garrett Cooper wrote:
>     According to the POSIX spec, using access(2) is implementation
> dependent when running as superuser [1]. FreeBSD intentionally returns
> true whenever euid/uid = 0 [2]. FreeBSD's /bin/sh doesn't have this
> `issue' with test(1). Example:
>
> $ ls -l typescript
> -rw-r--r--  1 gcooper  gcooper  37875 Jul 12 22:19 typescript
> $ sudo sh -c 'test -x typescript; echo $?'
> 1
> $ sudo bash -c 'test -x typescript; echo $?'
> 0
>
>     Code should be added to detect the mode via stat(2), instead of
> access(2) (the FreeBSD manpage also notes security issues with race
> conditions when using access(2), so access(2) use is discouraged).
>     If I can get the details for grabbing bash from cvs/svn/whatever,
> I'll whip up a patch for this.
> Thanks,
> -Garrett
>
> [1] http://www.opengroup.org/onlinepubs/000095399/functions/access.html
> - see RATIONALE.
> [2] http://www.freebsd.org/cgi/man.cgi?query=access