fanotify: Require fid_mode for any non-fd event

Like inode events, FAN_FS_ERROR will require fid mode.  Therefore,
convert the verification during fanotify_mark(2) to require fid for any
non-fd event.  This means fid_mode will not only be required for inode
events, but for any event that doesn't provide a descriptor.

Link: https://lore.kernel.org/r/20211025192746.66445-17-krisman@collabora.com
Suggested-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com>
Signed-off-by: Jan Kara <jack@suse.cz>

diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c
index adeae6d65e351148679af5d0eeae170c0f6fca11..66ee3c2805c7b928a1ba1b84660f43544dac50d3 100644 (file)
--- a/fs/notify/fanotify/fanotify_user.c
+++ b/fs/notify/fanotify/fanotify_user.c
@@ -1458,14 +1458,14 @@ static int do_fanotify_mark(int fanotify_fd, unsigned int flags, __u64 mask,
                goto fput_and_out;
 
        /*
-        * Events with data type inode do not carry enough information to report
-        * event->fd, so we do not allow setting a mask for inode events unless
-        * group supports reporting fid.
-        * inode events are not supported on a mount mark, because they do not
-        * carry enough information (i.e. path) to be filtered by mount point.
+        * Events that do not carry enough information to report
+        * event->fd require a group that supports reporting fid.  Those
+        * events are not supported on a mount mark, because they do not
+        * carry enough information (i.e. path) to be filtered by mount
+        * point.
         */
        fid_mode = FAN_GROUP_FLAG(group, FANOTIFY_FID_BITS);
-       if (mask & FANOTIFY_INODE_EVENTS &&
+       if (mask & ~(FANOTIFY_FD_EVENTS|FANOTIFY_EVENT_FLAGS) &&
            (!fid_mode || mark_type == FAN_MARK_MOUNT))
                goto fput_and_out;
 

diff --git a/include/linux/fanotify.h b/include/linux/fanotify.h
index eec3b7c40811528dfab87563cacffea4396a6021..52d464802d99fb11e16e121503fbdec155113b37 100644 (file)
--- a/include/linux/fanotify.h
+++ b/include/linux/fanotify.h
@@ -84,6 +84,9 @@ extern struct ctl_table fanotify_table[]; /* for sysctl */
  */
 #define FANOTIFY_DIRENT_EVENTS (FAN_MOVE | FAN_CREATE | FAN_DELETE)
 
+/* Events that can be reported with event->fd */
+#define FANOTIFY_FD_EVENTS (FANOTIFY_PATH_EVENTS | FANOTIFY_PERM_EVENTS)
+
 /* Events that can only be reported with data type FSNOTIFY_EVENT_INODE */
 #define FANOTIFY_INODE_EVENTS  (FANOTIFY_DIRENT_EVENTS | \
                                 FAN_ATTRIB | FAN_MOVE_SELF | FAN_DELETE_SELF)