Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]


Groups > linux.kernel > #1415205

Re: [PATCH] mailbox: mailbox-test: set tdev->signal to NULL after freeing

From Lee Jones <lee.jones@linaro.org>
Newsgroups linux.kernel
Subject Re: [PATCH] mailbox: mailbox-test: set tdev->signal to NULL after freeing
Date 2016-06-06 17:20 +0200
Message-ID <rH4tP-6DT-19@gated-at.bofh.it> (permalink)
References <rCndL-5Ak-9@gated-at.bofh.it>
Organization linux.* mail to news gateway

Show all headers | View raw


On Tue, 24 May 2016, Sudeep Holla wrote:

> tdev->signal is not set NULL after it's freed. This will cause random
> exceptions when the stale pointer is accessed after tdev->signal is
> freed. Also, since tdev->signal allocation is skipped the next time
> it's written, this leads to continuous fault finally leading to the
> total death of the system.
> 
> Cc: Lee Jones <lee.jones@linaro.org>
> Cc: Jassi Brar <jassisinghbrar@gmail.com>
> Fixes: d1c2f87c9a8f ("mailbox: mailbox-test: Prevent memory leak")
> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
> ---
>  drivers/mailbox/mailbox-test.c | 1 +
>  1 file changed, 1 insertion(+)

Strange there isn't a kfree_and_null() call.

Patch looks okay to me though:

Acked-by: Lee Jones <lee.jones@linaro.org>

> diff --git a/drivers/mailbox/mailbox-test.c b/drivers/mailbox/mailbox-test.c
> index 58d04726cdd7..9ca96e9db6bf 100644
> --- a/drivers/mailbox/mailbox-test.c
> +++ b/drivers/mailbox/mailbox-test.c
> @@ -133,6 +133,7 @@ static ssize_t mbox_test_message_write(struct file *filp,
>  out:
>  	kfree(tdev->signal);
>  	kfree(tdev->message);
> +	tdev->signal = NULL;
> 
>  	return ret < 0 ? ret : count;
>  }

-- 
Lee Jones
Linaro STMicroelectronics Landing Team Lead
Linaro.org │ Open source software for ARM SoCs
Follow Linaro: Facebook | Twitter | Blog

Back to linux.kernel | Previous | Next | Find similar | Unroll thread


Thread

Re: [PATCH] mailbox: mailbox-test: set tdev->signal to NULL after  freeing Lee Jones <lee.jones@linaro.org> - 2016-06-06 17:20 +0200

csiph-web