On Fri, 2016-02-05 at 21:44 +0000, Rainer Weikusat wrote: > The present unix_stream_read_generic contains various code sequences of > the form > > err = -EDISASTER; > if (<test>) > goto out; > > This has the unfortunate side effect of possibly causing the error code > to bleed through to the final > > out: > return copied ? : err; > > and then to be wrongly returned if no data was copied because the caller > didn't supply a data buffer, as demonstrated by the program available at > > http://pad.lv/1540731 > > Change it such that err is only set if an error condition was detected.
Well, if you replace the traditional flow err = -XXXX; if (test) goto out; Then please add unlikely() to at least give a hint to the compiler. if (unlikely(test)) { err = -XXX; goto out; } And please add a 'Fixes: .... ' tag for bug fixes. Thanks.