On Tue, Oct 11, 2005 at 10:56:43AM +0200, Grzegorz Nosek wrote:
> I found an (IMHO) silly bug in do_sendfile in 2.6.13.x kernels (at
> least in 2.6.13.3 and .4, didn't backtrack to find where it
> originated). Without the patch all I apparently get from sys_sendfile
> is an oops due to a call in sys_sendfile with ppos being NULL. With the
> patch it works OK. Noticed in vsftpd.
>
> @@ -719,7 +719,7 @@
> current->syscr++;
> current->syscw++;
>
> - if (*ppos > max)
> + if (ppos && *ppos > max)
That change can't fix a bug in 2.6.13, because ppos is forced to be
non-null further up the file:
622 static ssize_t do_sendfile(int out_fd, int in_fd, loff_t *ppos,
...
647 if (!ppos)
648 ppos = &in_file->f_pos;
...
684 pos = *ppos;
...
701 current->syscr++;
702 current->syscw++;
703
704 if (*ppos > max)
705 retval = -EOVERFLOW;
(line numbers from 2.6.13.)
So there must be something else at work. Perhaps your patches?
On Tue, Oct 11, 2005 at 04:53:47PM +0200, Jiri Slaby wrote:
> I don't know the code surrounding this, but shouldn't be this
> (!ppos || *ppos > max)?
That would be wrong, too; if it were valid to call in with ppos==0, you
wouldn't want to return EOVERFLOW; and if ppos==0 were not valid and you
wanted to return an error, EOVERFLOW would be the wrong error to return.
-andy
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
[Index of Archives]
[Kernel Newbies]
[Netfilter]
[Bugtraq]
[Photo]
[Stuff]
[Gimp]
[Yosemite News]
[MIPS Linux]
[ARM Linux]
[Linux Security]
[Linux RAID]
[Video 4 Linux]
[Linux for the blind]
[Linux Resources]
