Message-ID: <54C21A11.1010202@sunrus.com.cn>
Date: Fri, 23 Jan 2015 17:53:21 +0800
From: Chen Gang S <gang.chen@sunrus.com.cn>
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Subject: Re: [Qemu-devel] [PATCH] linux-user/syscall.c: Free the vec[i] in
 failure processing code block
To: riku.voipio@iki.fi
Cc: QEMU Trivial <qemu-trivial@nongnu.org>, qemu-devel <qemu-devel@nongnu.org>

On 1/23/15 17:36, Chen Gang S wrote:
> When failure occurs during allocating vec[i], also need free all
> allocated vec[i] in failure processing code block before return.
> 
> If error is EFAULT when "i == 0", vec[i].iov_base is NULL, then can just
> skip it, so can still use "while (--i >= 0)" for the free looping.
> 
> Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com>
> ---
>  linux-user/syscall.c | 5 +++++
>  1 file changed, 5 insertions(+)
> 
> diff --git a/linux-user/syscall.c b/linux-user/syscall.c
> index 290fdea..e6a8e49 100644
> --- a/linux-user/syscall.c
> +++ b/linux-user/syscall.c
> @@ -1873,6 +1873,11 @@ static struct iovec *lock_iovec(int type, abi_ulong target_addr,
>      return vec;
>  
>   fail:
> +    while (--i >= 0) {
> +        if (tswapal(vec[i].iov_len) > 0) {
> +            unlock_user(vec[i].iov_base, base, 0);

Oh, sorry, base is undefined here. I shall send patch v2 for it.

> +        }
> +    }
>      unlock_user(target_vec, target_addr, 0);
>   fail2:
>      free(vec);
> 

-- 
Chen Gang

Open, share, and attitude like air, water, and life which God blessed