[PATCH v2 5/5] dnotify: Pass argument of fcntl_dirnotify as int

From: Luca Vizzarro
Date: Fri Apr 14 2023 - 11:27:21 EST


The interface for fcntl expects the argument passed for the command
F_DIRNOTIFY to be of type int. The current code wrongly treats it as
a long. In order to avoid access to undefined bits, we should explicitly
cast the argument to int.

Cc: Jan Kara <jack@xxxxxxx>
Cc: Amir Goldstein <amir73il@xxxxxxxxx>
Cc: Alexander Viro <viro@xxxxxxxxxxxxxxxxxx>
Cc: Christian Brauner <brauner@xxxxxxxxxx>
Cc: Jeff Layton <jlayton@xxxxxxxxxx>
Cc: Chuck Lever <chuck.lever@xxxxxxxxxx>
Cc: Kevin Brodsky <Kevin.Brodsky@xxxxxxx>
Cc: Vincenzo Frascino <Vincenzo.Frascino@xxxxxxx>
Cc: Szabolcs Nagy <Szabolcs.Nagy@xxxxxxx>
Cc: "Theodore Ts'o" <tytso@xxxxxxx>
Cc: David Laight <David.Laight@xxxxxxxxxx>
Cc: Mark Rutland <Mark.Rutland@xxxxxxx>
Cc: linux-fsdevel@xxxxxxxxxxxxxxx
Cc: linux-morello@xxxxxxxxxxxxxxxxxxx
Acked-by: Jan Kara <jack@xxxxxxx>
Signed-off-by: Luca Vizzarro <Luca.Vizzarro@xxxxxxx>
---
fs/notify/dnotify/dnotify.c | 4 ++--
include/linux/dnotify.h | 4 ++--
2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/fs/notify/dnotify/dnotify.c b/fs/notify/dnotify/dnotify.c
index 190aa717fa32..ebdcc25df0f7 100644
--- a/fs/notify/dnotify/dnotify.c
+++ b/fs/notify/dnotify/dnotify.c
@@ -199,7 +199,7 @@ void dnotify_flush(struct file *filp, fl_owner_t id)
}

/* this conversion is done only at watch creation */
-static __u32 convert_arg(unsigned long arg)
+static __u32 convert_arg(unsigned int arg)
{
__u32 new_mask = FS_EVENT_ON_CHILD;

@@ -258,7 +258,7 @@ static int attach_dn(struct dnotify_struct *dn, struct dnotify_mark *dn_mark,
* up here. Allocate both a mark for fsnotify to add and a dnotify_struct to be
* attached to the fsnotify_mark.
*/
-int fcntl_dirnotify(int fd, struct file *filp, unsigned long arg)
+int fcntl_dirnotify(int fd, struct file *filp, unsigned int arg)
{
struct dnotify_mark *new_dn_mark, *dn_mark;
struct fsnotify_mark *new_fsn_mark, *fsn_mark;
diff --git a/include/linux/dnotify.h b/include/linux/dnotify.h
index b1d26f9f1c9f..9f183a679277 100644
--- a/include/linux/dnotify.h
+++ b/include/linux/dnotify.h
@@ -30,7 +30,7 @@ struct dnotify_struct {
FS_MOVED_FROM | FS_MOVED_TO)

extern void dnotify_flush(struct file *, fl_owner_t);
-extern int fcntl_dirnotify(int, struct file *, unsigned long);
+extern int fcntl_dirnotify(int, struct file *, unsigned int);

#else

@@ -38,7 +38,7 @@ static inline void dnotify_flush(struct file *filp, fl_owner_t id)
{
}

-static inline int fcntl_dirnotify(int fd, struct file *filp, unsigned long arg)
+static inline int fcntl_dirnotify(int fd, struct file *filp, unsigned int arg)
{
return -EINVAL;
}
--
2.34.1