From e49452c67703d3647467d65275fb893589384fed Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Wed, 16 Jan 2008 12:06:14 +0900 Subject: [PATCH] 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 Signed-off-by: Linus Torvalds --- fs/sysfs/dir.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c index 337162935d2..b197016bbfb 100644 --- a/fs/sysfs/dir.c +++ b/fs/sysfs/dir.c @@ -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); -- 2.41.1