On Wed, Aug 7, 2013 at 6:30 PM, Chen Gang <gang.c...@asianux.com> wrote: > On 08/08/2013 12:58 AM, Andy Lutomirski wrote: >> On Wed, Aug 7, 2013 at 9:21 AM, Oleg Nesterov <o...@redhat.com> wrote: >>> On 08/06, Andy Lutomirski wrote: >>>> >>>> I assume that what the man page means is that the return value is >>>> whatever fsgid was prior to the call. On error, fsgid isn't changed, so >>>> the return value is still "current". >>> >>> Probably... Still >>> >>> On success, the previous value of fsuid is returned. >>> On error, the current value of fsuid is returned. >>> >>> looks confusing. sys_setfsuid() always returns the old value. >>> >>>> (FWIW, this behavior is awful and is probably the cause of a security >>>> bug or three, since success and failure are indistinguishable. >>> >>> At least this all looks strange. >>> >>> I dunno if we can change this old behaviour. I won't be surprized >>> if someone already uses setfsuid(-1) as getfsuid(). >> > > Oh, really it is. > > Hmm... as a pair function, we need add getfsuid() too, if we do not add > it, it will make negative effect with setfsuid(). > > Since it is a system call, we have to keep compitable. > > So in my opinion, better add getfsuid2()/setfsuid2() instead of current > setfsuid()
How about getfsuid() and setfsuid2()? --Andy -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
