From b1085ba80cd2784400a7beec3fda5099198ed01c Mon Sep 17 00:00:00 2001 From: Lino Sanfilippo Date: Fri, 5 Nov 2010 17:05:27 +0100 Subject: [PATCH] fanotify: if set by user unset FMODE_NONOTIFY before fsnotify_perm() is called Unsetting FMODE_NONOTIFY in fsnotify_open() is too late, since fsnotify_perm() is called before. If FMODE_NONOTIFY is set fsnotify_perm() will skip permission checks, so a user can still disable permission checks by setting this flag in an open() call. This patch corrects this by unsetting the flag before fsnotify_perm is called. Signed-off-by: Lino Sanfilippo Signed-off-by: Eric Paris --- fs/namei.c | 3 +++ include/linux/fsnotify.h | 3 --- 2 files changed, 3 insertions(+), 3 deletions(-) diff --git a/fs/namei.c b/fs/namei.c index 5362af9b7372..4ff7ca530533 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -1748,6 +1748,9 @@ struct file *do_filp_open(int dfd, const char *pathname, if (!(open_flag & O_CREAT)) mode = 0; + /* Must never be set by userspace */ + open_flag &= ~FMODE_NONOTIFY; + /* * O_SYNC is implemented as __O_SYNC|O_DSYNC. As many places only * check for O_DSYNC if the need any syncing at all we enforce it's diff --git a/include/linux/fsnotify.h b/include/linux/fsnotify.h index 5c185fa27089..b10bcdeaef76 100644 --- a/include/linux/fsnotify.h +++ b/include/linux/fsnotify.h @@ -235,9 +235,6 @@ static inline void fsnotify_open(struct file *file) if (S_ISDIR(inode->i_mode)) mask |= FS_ISDIR; - /* FMODE_NONOTIFY must never be set from user */ - file->f_mode &= ~FMODE_NONOTIFY; - fsnotify_parent(path, NULL, mask); fsnotify(inode, mask, path, FSNOTIFY_EVENT_PATH, NULL, 0); } -- 2.34.1