[PATCH] sysfs: sysfs_remove_dir() needs to invalidate the dentry

When calling sysfs_remove_dir() don't allow any further sysfs functions to work for this kobject anymore. This fixes a nasty USB cdc-acm oops on disconnect. Many thanks to Bob Copeland and Paul Fulghum for taking the time to track this down. Cc: Bob Copeland <[email protected]> Cc: Paul Fulghum <[email protected]> Cc: Maneesh Soni <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
mna · Mar 20, 2006 · 641e6f3 · 641e6f3
1 parent c4a1745
commit 641e6f3
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diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c
@@ -302,6 +302,7 @@ void sysfs_remove_dir(struct kobject * kobj)
 	 * Drop reference from dget() on entrance.
 	 */
 	dput(dentry);
+	kobj->dentry = NULL;
 }
 
 int sysfs_rename_dir(struct kobject * kobj, const char *new_name)

diff --git a/fs/sysfs/inode.c b/fs/sysfs/inode.c
@@ -227,12 +227,16 @@ void sysfs_drop_dentry(struct sysfs_dirent * sd, struct dentry * parent)
 void sysfs_hash_and_remove(struct dentry * dir, const char * name)
 {
 	struct sysfs_dirent * sd;
-	struct sysfs_dirent * parent_sd = dir->d_fsdata;
+	struct sysfs_dirent * parent_sd;
+
+	if (!dir)
+		return;
 
 	if (dir->d_inode == NULL)
 		/* no inode means this hasn't been made visible yet */
 		return;
 
+	parent_sd = dir->d_fsdata;
 	mutex_lock(&dir->d_inode->i_mutex);
 	list_for_each_entry(sd, &parent_sd->s_children, s_sibling) {
 		if (!sd->s_element)