sysfs: make sysfs_lookup() return ERR_PTR(-ENOENT) on failed lookup

sysfs tries to keep dcache a strict subset of sysfs_dirent tree by
shooting down dentries when a node is removed, that is, no negative
dentry for sysfs.  However, the lookup function returned NULL and thus
created negative dentries when the target node didn't exist.

Make sysfs_lookup() return ERR_PTR(-ENOENT) on lookup failure.  This
fixes the NULL dereference bug in sysfs_get_dentry() discovered by
bluetooth rfcomm device moving around.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Tejun Heo 2008-01-16 12:06:14 +09:00 коммит произвёл Linus Torvalds
Родитель cbd9c88369
Коммит e49452c677
1 изменённых файлов: 3 добавлений и 1 удалений

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@ -678,8 +678,10 @@ static struct dentry * sysfs_lookup(struct inode *dir, struct dentry *dentry,
sd = sysfs_find_dirent(parent_sd, dentry->d_name.name);
/* no such entry */
if (!sd)
if (!sd) {
ret = ERR_PTR(-ENOENT);
goto out_unlock;
}
/* attach dentry and inode */
inode = sysfs_get_inode(sd);