All of lore.kernel.org
 help / color / mirror / Atom feed
* [PATCH] isdn/i4l: add error handling for try_module_get
@ 2018-06-12  4:43 Zhouyang Jia
  2018-06-12 10:11 ` Sergei Shtylyov
  0 siblings, 1 reply; 2+ messages in thread
From: Zhouyang Jia @ 2018-06-12  4:43 UTC (permalink / raw)
  Cc: Zhouyang Jia, Karsten Keil, Kees Cook, Annie Cherkaev, Al Viro,
	Jiten Thakkar, netdev, linux-kernel

When try_module_get fails, the lack of error-handling code may
cause unexpected results.

This patch adds error-handling code after calling try_module_get.

Signed-off-by: Zhouyang Jia <jiazhouyang09@gmail.com>
---
 drivers/isdn/i4l/isdn_common.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/isdn/i4l/isdn_common.c b/drivers/isdn/i4l/isdn_common.c
index 7c6f3f5..7e52851 100644
--- a/drivers/isdn/i4l/isdn_common.c
+++ b/drivers/isdn/i4l/isdn_common.c
@@ -71,7 +71,8 @@ static int isdn_add_channels(isdn_driver_t *d, int drvidx, int n, int adding);
 static inline void
 isdn_lock_driver(isdn_driver_t *drv)
 {
-	try_module_get(drv->interface->owner);
+	if (!try_module_get(drv->interface->owner))
+		printk(KERN_WARNING "isdn_lock_driver: cannot get module\n");
 	drv->locks++;
 }
 
-- 
2.7.4


^ permalink raw reply related	[flat|nested] 2+ messages in thread

* Re: [PATCH] isdn/i4l: add error handling for try_module_get
  2018-06-12  4:43 [PATCH] isdn/i4l: add error handling for try_module_get Zhouyang Jia
@ 2018-06-12 10:11 ` Sergei Shtylyov
  0 siblings, 0 replies; 2+ messages in thread
From: Sergei Shtylyov @ 2018-06-12 10:11 UTC (permalink / raw)
  To: Zhouyang Jia
  Cc: Karsten Keil, Kees Cook, Annie Cherkaev, Al Viro, Jiten Thakkar,
	netdev, linux-kernel

On 6/12/2018 7:43 AM, Zhouyang Jia wrote:

> When try_module_get fails, the lack of error-handling code may
> cause unexpected results.
> 
> This patch adds error-handling code after calling try_module_get.
> 
> Signed-off-by: Zhouyang Jia <jiazhouyang09@gmail.com>
> ---
>   drivers/isdn/i4l/isdn_common.c | 3 ++-
>   1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/isdn/i4l/isdn_common.c b/drivers/isdn/i4l/isdn_common.c
> index 7c6f3f5..7e52851 100644
> --- a/drivers/isdn/i4l/isdn_common.c
> +++ b/drivers/isdn/i4l/isdn_common.c
> @@ -71,7 +71,8 @@ static int isdn_add_channels(isdn_driver_t *d, int drvidx, int n, int adding);
>   static inline void
>   isdn_lock_driver(isdn_driver_t *drv)
>   {
> -	try_module_get(drv->interface->owner);
> +	if (!try_module_get(drv->interface->owner))
> +		printk(KERN_WARNING "isdn_lock_driver: cannot get module\n");

    Do you call this error handling code? :-)
    And BTW we have pr_warn() for that.

>   	drv->locks++;
>   }
>   

MBR, Sergei

^ permalink raw reply	[flat|nested] 2+ messages in thread

end of thread, other threads:[~2018-06-12 10:11 UTC | newest]

Thread overview: 2+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2018-06-12  4:43 [PATCH] isdn/i4l: add error handling for try_module_get Zhouyang Jia
2018-06-12 10:11 ` Sergei Shtylyov

This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.