[PATCH] inotify: oops fix

Bug fix: Ensure that the fd passed to inotify_add_watch() and
inotify_rm_watch() belongs to inotify.

Signed-off-by: Robert Love <rml@novell.com>
Signed-off-by: John McCutchan <ttb@tentacle.dhs.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 15 insertions, 1 deletions

diff --git a/fs/inotify.c b/fs/inotify.c
index 807209f0bcda..b55d6e4a0911 100644
--- a/fs/inotify.c
+++ b/fs/inotify.c
@@ -929,6 +929,12 @@ asmlinkage long sys_inotify_add_watch(int fd, const char __user *path, u32 mask)
         if (unlikely(!filp))
                 return -EBADF;
 
+        /* verify that this is indeed an inotify instance */
+        if (unlikely(filp->f_op != &inotify_fops)) {
+                ret = -EINVAL;
+                goto fput_and_out;
+        }
+
         ret = find_inode(path, &nd);
         if (unlikely(ret))
                 goto fput_and_out;
@@ -986,10 +992,18 @@ asmlinkage long sys_inotify_rm_watch(int fd, u32 wd)
         filp = fget_light(fd, &fput_needed);
         if (unlikely(!filp))
                 return -EBADF;
+
+        /* verify that this is indeed an inotify instance */
+        if (unlikely(filp->f_op != &inotify_fops)) {
+                ret = -EINVAL;
+                goto out;
+        }
+
         dev = filp->private_data;
         ret = inotify_ignore(dev, wd);
-        fput_light(filp, fput_needed);
 
+out:
+        fput_light(filp, fput_needed);
         return ret;
 }