[PATCH][next] media: usb: siano: Fix undefined behavior bug in struct smsusb_urb_t

From: Gustavo A. R. Silva
Date: Fri Sep 29 2023 - 11:42:21 EST


`struct urb` is a flexible structure, which means that it contains a
flexible-array member at the bottom. This could potentially lead to an
overwrite of the object `wq` at run-time with the contents of `urb`.

Fix this by placing object `urb` at the end of `struct smsusb_urb_t`.

Fixes: dd47fbd40e6e ("[media] smsusb: don't sleep while atomic")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Gustavo A. R. Silva <gustavoars@xxxxxxxxxx>
---
drivers/media/usb/siano/smsusb.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/media/usb/siano/smsusb.c b/drivers/media/usb/siano/smsusb.c
index 9d9e14c858e6..2c048f8e8371 100644
--- a/drivers/media/usb/siano/smsusb.c
+++ b/drivers/media/usb/siano/smsusb.c
@@ -40,10 +40,10 @@ struct smsusb_urb_t {
struct smscore_buffer_t *cb;
struct smsusb_device_t *dev;

- struct urb urb;
-
/* For the bottom half */
struct work_struct wq;
+
+ struct urb urb;
};

struct smsusb_device_t {
--
2.34.1