[PATCH] usb: gadget: f_midi: prefer strscpy() over strcpy()

[PATCH] usb: gadget: f_midi: prefer strscpy() over strcpy()

[Abdul Rahim]

The function strcpy() is depreciated and potentially unsafe. It performs
no bounds checking on the destination buffer. This could result in
linear overflows beyond the end of the buffer, leading to all kinds of
misbehaviors. The safe replacement is strscpy() [1].

this fixes checkpatch warning:
    WARNING: Prefer strscpy over strcpy

Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strcpy [1]
Signed-off-by: Abdul Rahim <abdul.rahim@myyahoo.com>
---
 drivers/usb/gadget/function/f_midi.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/usb/gadget/function/f_midi.c b/drivers/usb/gadget/function/f_midi.c
index 1067847cc079..837fcdfa3840 100644
--- a/drivers/usb/gadget/function/f_midi.c
+++ b/drivers/usb/gadget/function/f_midi.c
@@ -819,9 +819,9 @@ static int f_midi_register_card(struct f_midi *midi)
 		goto fail;
 	}
 
-	strcpy(card->driver, f_midi_longname);
-	strcpy(card->longname, f_midi_longname);
-	strcpy(card->shortname, f_midi_shortname);
+	strscpy(card->driver, f_midi_longname);
+	strscpy(card->longname, f_midi_longname);
+	strscpy(card->shortname, f_midi_shortname);
 
 	/* Set up rawmidi */
 	snd_component_add(card, "MIDI");
@@ -833,7 +833,7 @@ static int f_midi_register_card(struct f_midi *midi)
 	}
 	midi->rmidi = rmidi;
 	midi->in_last_port = 0;
-	strcpy(rmidi->name, card->shortname);
+	strscpy(rmidi->name, card->shortname);
 	rmidi->info_flags = SNDRV_RAWMIDI_INFO_OUTPUT |
 			    SNDRV_RAWMIDI_INFO_INPUT |
 			    SNDRV_RAWMIDI_INFO_DUPLEX;
-- 
2.46.0

Re: [PATCH] usb: gadget: f_midi: prefer strscpy() over strcpy()

[Kees Cook]

On Sun, Sep 15, 2024 at 04:47:49AM +0530, Abdul Rahim wrote:
> The function strcpy() is depreciated and potentially unsafe. It performs
> no bounds checking on the destination buffer. This could result in
> linear overflows beyond the end of the buffer, leading to all kinds of
> misbehaviors. The safe replacement is strscpy() [1].
> 
> this fixes checkpatch warning:
>     WARNING: Prefer strscpy over strcpy
> 
> Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strcpy [1]
> Signed-off-by: Abdul Rahim <abdul.rahim@myyahoo.com>

Yup, these look good. Thanks!

Reviewed-by: Kees Cook <kees@kernel.org>

-- 
Kees Cook