diff options
author | Christoph Hellwig <hch@lst.de> | 2008-02-15 14:37:24 -0800 |
---|---|---|
committer | Al Viro <viro@zeniv.linux.org.uk> | 2008-03-19 06:50:44 -0400 |
commit | 322ee5b36eac42e762526b0df7fa432beba6e7a0 (patch) | |
tree | 2499695b67123a8d463a1e59e91aa793f4803c10 | |
parent | 3227e14c3cab5ef7972c72eb13c13de444b5bfbc (diff) |
[PATCH] check for null vfsmount in dentry_open()
Make sure no-one calls dentry_open with a NULL vfsmount argument and crap
out with a stacktrace otherwise. A NULL file->f_vfsmnt has always been
problematic, but with the per-mount r/o tracking we can't accept anymore
at all.
[AV] the last place that passed NULL had been eliminated by the previous
patch (reiserfs xattr stuff)
Acked-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
-rw-r--r-- | fs/open.c | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/fs/open.c b/fs/open.c index 54198538b67e..a4b12022edaa 100644 --- a/fs/open.c +++ b/fs/open.c @@ -903,6 +903,18 @@ struct file *dentry_open(struct dentry *dentry, struct vfsmount *mnt, int flags) int error; struct file *f; + /* + * We must always pass in a valid mount pointer. Historically + * callers got away with not passing it, but we must enforce this at + * the earliest possible point now to avoid strange problems deep in the + * filesystem stack. + */ + if (!mnt) { + printk(KERN_WARNING "%s called with NULL vfsmount\n", __func__); + dump_stack(); + return ERR_PTR(-EINVAL); + } + error = -ENFILE; f = get_empty_filp(); if (f == NULL) { |