Messages in this thread Patch in this message | | | Subject | [RFC][PATCH 03/30] check for null vfsmount in dentry_open() | From | Dave Hansen <> | Date | Fri, 08 Feb 2008 14:26:45 -0800 |
| |
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.
Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Dave Hansen <haveblue@us.ibm.com> ---
linux-2.6.git-dave/fs/open.c | 12 ++++++++++++ 1 file changed, 12 insertions(+)
diff -puN fs/open.c~check-for-NULL-vfsmount-in-dentry-open fs/open.c --- linux-2.6.git/fs/open.c~check-for-NULL-vfsmount-in-dentry-open 2008-02-08 13:04:45.000000000 -0800 +++ linux-2.6.git-dave/fs/open.c 2008-02-08 13:04:45.000000000 -0800 @@ -906,6 +906,18 @@ struct file *dentry_open(struct dentry * 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) { _
| |