On Sat, Jan 28, 2012 at 07:12:25PM -0500, David Schultz wrote: > On Sat, Jan 28, 2012, Kostik Belousov wrote: > > On Fri, Jan 27, 2012 at 02:42:21PM -0500, David Schultz wrote: > > > On Fri, Jan 27, 2012, Kostik Belousov wrote: > > > > On Fri, Jan 27, 2012 at 07:50:30PM +1100, Bruce Evans wrote: > > > > > On Thu, 26 Jan 2012, Gleb Smirnoff wrote: > > > > > > > > > > >On Thu, Jan 26, 2012 at 11:53:57PM +1100, Bruce Evans wrote: > > > > > >B> > @@ -1552,6 +1552,12 @@ aio_aqueue(struct thread *td, struct aio > > > > > >B> > return (error); > > > > > >B> > } > > > > > >B> > > > > > > >B> > + /* XXX: aio_nbytes is later casted to signed types. */ > > > > > >B> > + if ((int)aiocbe->uaiocb.aio_nbytes < 0) { > > > > > >B> > > > > > >B> This should avoid implementation-defined behaviour by checking if > > > > > >B> > > > > > >B> (uncast)aiocbe->uaiocb.aio_nbytes > INT_MAX. > > > > > > > > > > >Is the attached patch okay? > > > > > > > > > > Yes. It now matches the style used for read^Wsys_read() and friends. > > > > > This used to have to fit the count in "int uio_resid". uio_resid now > > > > > has type ssize_t, but for some reason the old INT_MAX limits remain. > > > > > > > > Well, I can revive the patch. I still think it is good to get rid of > > > > the limit. > > > > > > The correct limit on the maximum size of a single read/write is > > > SSIZE_MAX, but FreeBSD uses INT_MAX. It's not safe to raise the > > > limit yet, though, because of bugs in several filesystems. For > > > example, FFS copies uio_resid into a local variable of type int. > > > I have some old patches that fix some of these issues for FFS and > > > cd9660, but surely there are more places I didn't notice. > > > > > Absolutely agree. > > > > http://people.freebsd.org/~kib/misc/uio_resid.5.patch > > Nice. You found a lot more than I've got in my tree, and you even > fixed the return values. There are at least a few more places to > fix. For instance, cd9660 and the NFS client pass uio_resid or > iov_len to min(), which operates on ints. (Incidentally, C11 > generics ought to make it possible to write type-generic min() > and max() functions.)
Thank you, http://people.freebsd.org/~kib/misc/uio_resid.6.patch changed them to MIN().
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