[PATCH] autofs4: avoid panic on bind mount of autofs owned directory
While this is not a solution to bind and move mounts on autofs owned
directories it is necessary to fix the trady error handling.
At least it avoids the kernel panic I observed checking out bug #4589.
Signed-off-by: Ian Kent <raven@themaw.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/fs/autofs4/root.c b/fs/autofs4/root.c
index 3765c04..e137acf 100644
--- a/fs/autofs4/root.c
+++ b/fs/autofs4/root.c
@@ -205,7 +205,11 @@
struct vfsmount *fp_mnt = mntget(mnt);
struct dentry *fp_dentry = dget(dentry);
- while (follow_down(&fp_mnt, &fp_dentry) && d_mountpoint(fp_dentry));
+ if (!autofs4_follow_mount(&fp_mnt, &fp_dentry)) {
+ dput(fp_dentry);
+ mntput(fp_mnt);
+ return -ENOENT;
+ }
fp = dentry_open(fp_dentry, fp_mnt, file->f_flags);
status = PTR_ERR(fp);