[PATCH v2] media: usb: siano: Fix allocation of urbs

From: Ricardo Ribalda
Date: Mon Apr 15 2024 - 08:13:28 EST


USB urbs must be allocated with usb_alloc_urb. Quoting the manual

Only use this function (usb_init_urb) if you _really_ understand what you
are doing.

Fix the following smatch error:

drivers/media/usb/siano/smsusb.c:53:38: warning: array of flexible structures

Signed-off-by: Ricardo Ribalda <ribalda@xxxxxxxxxxxx>
---
Changes in v2: Thanks Hans
- Only leave 1/6, the other ones are in another PR
- Fix the return tag and NULLify the urbs on return
- Link to v1: https://lore.kernel.org/r/20240410-smatch-v1-0-785d009a852b@xxxxxxxxxxxx
---
drivers/media/usb/siano/smsusb.c | 36 ++++++++++++++++++++++++++----------
1 file changed, 26 insertions(+), 10 deletions(-)

diff --git a/drivers/media/usb/siano/smsusb.c b/drivers/media/usb/siano/smsusb.c
index 723510520d09..2e25b970946a 100644
--- a/drivers/media/usb/siano/smsusb.c
+++ b/drivers/media/usb/siano/smsusb.c
@@ -40,7 +40,7 @@ struct smsusb_urb_t {
struct smscore_buffer_t *cb;
struct smsusb_device_t *dev;

- struct urb urb;
+ struct urb *urb;

/* For the bottom half */
struct work_struct wq;
@@ -160,7 +160,7 @@ static int smsusb_submit_urb(struct smsusb_device_t *dev,
}

usb_fill_bulk_urb(
- &surb->urb,
+ surb->urb,
dev->udev,
usb_rcvbulkpipe(dev->udev, dev->in_ep),
surb->cb->p,
@@ -168,9 +168,9 @@ static int smsusb_submit_urb(struct smsusb_device_t *dev,
smsusb_onresponse,
surb
);
- surb->urb.transfer_flags |= URB_FREE_BUFFER;
+ surb->urb->transfer_flags |= URB_FREE_BUFFER;

- return usb_submit_urb(&surb->urb, GFP_ATOMIC);
+ return usb_submit_urb(surb->urb, GFP_ATOMIC);
}

static void smsusb_stop_streaming(struct smsusb_device_t *dev)
@@ -178,7 +178,7 @@ static void smsusb_stop_streaming(struct smsusb_device_t *dev)
int i;

for (i = 0; i < MAX_URBS; i++) {
- usb_kill_urb(&dev->surbs[i].urb);
+ usb_kill_urb(dev->surbs[i].urb);
if (dev->surbs[i].wq.func)
cancel_work_sync(&dev->surbs[i].wq);

@@ -338,6 +338,8 @@ static void smsusb_term_device(struct usb_interface *intf)
struct smsusb_device_t *dev = usb_get_intfdata(intf);

if (dev) {
+ int i;
+
dev->state = SMSUSB_DISCONNECTED;

smsusb_stop_streaming(dev);
@@ -346,6 +348,11 @@ static void smsusb_term_device(struct usb_interface *intf)
if (dev->coredev)
smscore_unregister_device(dev->coredev);

+ for (i = 0; i < MAX_URBS; i++) {
+ usb_free_urb(dev->surbs[i].urb);
+ dev->surbs[i].urb = NULL;
+ }
+
pr_debug("device 0x%p destroyed\n", dev);
kfree(dev);
}
@@ -390,6 +397,7 @@ static int smsusb_init_device(struct usb_interface *intf, int board_id)
void *mdev;
int i, rc;
int align = 0;
+ int n_urb = 0;

/* create device object */
dev = kzalloc(sizeof(struct smsusb_device_t), GFP_KERNEL);
@@ -461,16 +469,18 @@ static int smsusb_init_device(struct usb_interface *intf, int board_id)
dev->coredev->is_usb_device = true;

/* initialize urbs */
- for (i = 0; i < MAX_URBS; i++) {
- dev->surbs[i].dev = dev;
- usb_init_urb(&dev->surbs[i].urb);
+ for (n_urb = 0; n_urb < MAX_URBS; n_urb++) {
+ dev->surbs[n_urb].dev = dev;
+ dev->surbs[n_urb].urb = usb_alloc_urb(0, GFP_KERNEL);
+ if (!dev->surbs[n_urb].urb)
+ goto free_urbs;
}

pr_debug("smsusb_start_streaming(...).\n");
rc = smsusb_start_streaming(dev);
if (rc < 0) {
pr_err("smsusb_start_streaming(...) failed\n");
- goto err_unregister_device;
+ goto free_urbs;
}

dev->state = SMSUSB_ACTIVE;
@@ -478,13 +488,19 @@ static int smsusb_init_device(struct usb_interface *intf, int board_id)
rc = smscore_start_device(dev->coredev);
if (rc < 0) {
pr_err("smscore_start_device(...) failed\n");
- goto err_unregister_device;
+ goto free_urbs;
}

pr_debug("device 0x%p created\n", dev);

return rc;

+free_urbs:
+ for (i = 0; i < n_urb; i++) {
+ usb_free_urb(dev->surbs[n_urb].urb);
+ dev->surbs[n_urb].urb = NULL;
+ }
+
err_unregister_device:
smsusb_term_device(intf);
#ifdef CONFIG_MEDIA_CONTROLLER_DVB

---
base-commit: 34d7bf1c8e59f5fbf438ee32c96389ebe41ca2e8
change-id: 20240410-smatch-8f235d50753d

Best regards,
--
Ricardo Ribalda <ribalda@xxxxxxxxxxxx>