Commit b1085ba8 authored by Lino Sanfilippo's avatar Lino Sanfilippo Committed by Eric Paris

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: default avatarLino Sanfilippo <LinoSanfilippo@gmx.de>
Signed-off-by: default avatarEric Paris <eparis@redhat.com>
parent 88d60c32
......@@ -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
......
......@@ -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);
}
......
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