Clang warns:
drivers/usb/cdns3/cdns3-gadget.c:2290:11: error: variable 'priv_dev' is uninitialized when used here [-Werror,-Wuninitialized]
dev_dbg(priv_dev->dev, "usbss: invalid parameters\n");
^~~~~~~~
include/linux/dev_printk.h:155:18: note: expanded from macro 'dev_dbg'
dynamic_dev_dbg(dev, dev_fmt(fmt), ##__VA_ARGS__)
^~~
include/linux/dynamic_debug.h:167:7: note: expanded from macro 'dynamic_dev_dbg'
dev, fmt, ##__VA_ARGS__)
^~~
include/linux/dynamic_debug.h:152:56: note: expanded from macro '_dynamic_func_call'
__dynamic_func_call(__UNIQUE_ID(ddebug), fmt, func, ##__VA_ARGS__)
^~~~~~~~~~~
include/linux/dynamic_debug.h:134:15: note: expanded from macro '__dynamic_func_call'
func(&id, ##__VA_ARGS__); \
^~~~~~~~~~~
drivers/usb/cdns3/cdns3-gadget.c:2278:31: note: initialize the variable 'priv_dev' to silence this warning
struct cdns3_device *priv_dev;
^
= NULL
1 error generated.
The priv_dev assignment was moved below the if statement to avoid
potentially dereferencing ep before it was checked but priv_dev is used
in the dev_dbg() call.
To fix this, move the priv_dev and comp_desc assignments back to their
original spot and hoist the ep check above those assignments with a call
to pr_debug() instead of dev_dbg().
Fixes: c3ffc9c4ca44 ("usb: cdns3: change place of 'priv_ep' assignment in cdns3_gadget_ep_dequeue(), cdns3_gadget_ep_enable()")
Link: https://github.com/ClangBuiltLinux/linux/issues/1680
Signed-off-by: Nathan Chancellor <[email protected]>
---
drivers/usb/cdns3/cdns3-gadget.c | 12 ++++++++----
1 file changed, 8 insertions(+), 4 deletions(-)
diff --git a/drivers/usb/cdns3/cdns3-gadget.c b/drivers/usb/cdns3/cdns3-gadget.c
index 9ac7d0a8c5da..d21b69997e75 100644
--- a/drivers/usb/cdns3/cdns3-gadget.c
+++ b/drivers/usb/cdns3/cdns3-gadget.c
@@ -2284,16 +2284,20 @@ static int cdns3_gadget_ep_enable(struct usb_ep *ep,
int ret = 0;
int val;
+ if (!ep) {
+ pr_debug("usbss: ep not configured?\n");
+ return -EINVAL;
+ }
+
priv_ep = ep_to_cdns3_ep(ep);
+ priv_dev = priv_ep->cdns3_dev;
+ comp_desc = priv_ep->endpoint.comp_desc;
- if (!ep || !desc || desc->bDescriptorType != USB_DT_ENDPOINT) {
+ if (!desc || desc->bDescriptorType != USB_DT_ENDPOINT) {
dev_dbg(priv_dev->dev, "usbss: invalid parameters\n");
return -EINVAL;
}
- comp_desc = priv_ep->endpoint.comp_desc;
- priv_dev = priv_ep->cdns3_dev;
-
if (!desc->wMaxPacketSize) {
dev_err(priv_dev->dev, "usbss: missing wMaxPacketSize\n");
return -EINVAL;
base-commit: 8288c99fc263bcafc5df5fa8c278b2eb8106364e
--
2.37.1
On 22-08-03 09:24:22, Nathan Chancellor wrote:
> Clang warns:
>
> drivers/usb/cdns3/cdns3-gadget.c:2290:11: error: variable 'priv_dev' is uninitialized when used here [-Werror,-Wuninitialized]
> dev_dbg(priv_dev->dev, "usbss: invalid parameters\n");
> ^~~~~~~~
> include/linux/dev_printk.h:155:18: note: expanded from macro 'dev_dbg'
> dynamic_dev_dbg(dev, dev_fmt(fmt), ##__VA_ARGS__)
> ^~~
> include/linux/dynamic_debug.h:167:7: note: expanded from macro 'dynamic_dev_dbg'
> dev, fmt, ##__VA_ARGS__)
> ^~~
> include/linux/dynamic_debug.h:152:56: note: expanded from macro '_dynamic_func_call'
> __dynamic_func_call(__UNIQUE_ID(ddebug), fmt, func, ##__VA_ARGS__)
> ^~~~~~~~~~~
> include/linux/dynamic_debug.h:134:15: note: expanded from macro '__dynamic_func_call'
> func(&id, ##__VA_ARGS__); \
> ^~~~~~~~~~~
> drivers/usb/cdns3/cdns3-gadget.c:2278:31: note: initialize the variable 'priv_dev' to silence this warning
> struct cdns3_device *priv_dev;
> ^
> = NULL
> 1 error generated.
>
> The priv_dev assignment was moved below the if statement to avoid
> potentially dereferencing ep before it was checked but priv_dev is used
> in the dev_dbg() call.
>
> To fix this, move the priv_dev and comp_desc assignments back to their
> original spot and hoist the ep check above those assignments with a call
> to pr_debug() instead of dev_dbg().
>
> Fixes: c3ffc9c4ca44 ("usb: cdns3: change place of 'priv_ep' assignment in cdns3_gadget_ep_dequeue(), cdns3_gadget_ep_enable()")
> Link: https://github.com/ClangBuiltLinux/linux/issues/1680
> Signed-off-by: Nathan Chancellor <[email protected]>
Acked-by: Peter Chen <[email protected]>
> ---
> drivers/usb/cdns3/cdns3-gadget.c | 12 ++++++++----
> 1 file changed, 8 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/usb/cdns3/cdns3-gadget.c b/drivers/usb/cdns3/cdns3-gadget.c
> index 9ac7d0a8c5da..d21b69997e75 100644
> --- a/drivers/usb/cdns3/cdns3-gadget.c
> +++ b/drivers/usb/cdns3/cdns3-gadget.c
> @@ -2284,16 +2284,20 @@ static int cdns3_gadget_ep_enable(struct usb_ep *ep,
> int ret = 0;
> int val;
>
> + if (!ep) {
> + pr_debug("usbss: ep not configured?\n");
> + return -EINVAL;
> + }
> +
> priv_ep = ep_to_cdns3_ep(ep);
> + priv_dev = priv_ep->cdns3_dev;
> + comp_desc = priv_ep->endpoint.comp_desc;
>
> - if (!ep || !desc || desc->bDescriptorType != USB_DT_ENDPOINT) {
> + if (!desc || desc->bDescriptorType != USB_DT_ENDPOINT) {
> dev_dbg(priv_dev->dev, "usbss: invalid parameters\n");
> return -EINVAL;
> }
>
> - comp_desc = priv_ep->endpoint.comp_desc;
> - priv_dev = priv_ep->cdns3_dev;
> -
> if (!desc->wMaxPacketSize) {
> dev_err(priv_dev->dev, "usbss: missing wMaxPacketSize\n");
> return -EINVAL;
>
> base-commit: 8288c99fc263bcafc5df5fa8c278b2eb8106364e
> --
> 2.37.1
>
--
Thanks,
Peter Chen