Hi Dan,
On Fri, 19 Nov 2010, Dan Carpenter wrote:
> Hi hi!
>
> This is a smatch thing. We check if last is NULL and then dereference
> it later with out checking. It might be worth looking at. I'm not
> familiar enough with the code to know the fix.
>
> It comes from:
> commit 2817b000b02c5f0c05af67c01fb2684e1381d6ef
> Author: Sage Weil <sage@xxxxxxxxxxxx>
> Date: Tue Oct 6 11:31:08 2009 -0700
>
> ceph: directory operations
>
> regards,
> dan carpenter
>
> fs/ceph/dir.c +124 __dcache_readdir(28) error: we previously assumed 'last' could be null.
> 116 /* start at beginning? */
> 117 if (filp->f_pos == 2 || (last &&
> ^^^^
> checked here.
>
> 118 filp->f_pos < ceph_dentry(last)->offset)) {
> 119 if (list_empty(&parent->d_subdirs))
> 120 goto out_unlock;
> 121 p = parent->d_subdirs.prev;
> 122 dout(" initial p %p/%p\n", p->prev, p->next);
> 123 } else {
> 124 p = last->d_u.d_child.prev;
> ^^^^^^^^^^^^^^^^^^^^^^
> dereferenced here.
Yep, that's a bit weird. Normally last is only NULL when filp->f_pos ==
2, so this doesn't normally come up, but it could if you were a weirdo and
llseeked forward on the dir. I'll fix it up.
Thanks!
sage
--
To unsubscribe from this list: send the line "unsubscribe ceph-devel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
