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Date: Fri, 13 Mar 2015 13:50:46 +0100
From: Paolo Bonzini <pbonzini@redhat.com>
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Subject: Re: [Qemu-devel] [PATCH] hw/9pfs/virtio-9p-proxy: Fix possible
	overflow
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To: Shannon Zhao <zhaoshenglong@huawei.com>, qemu-devel@nongnu.org
Cc: peter.maydell@linaro.org, hangaohuai@huawei.com, qemu-trivial@nongnu.org, mjt@tls.msk.ru, peter.huangpeng@huawei.com, aneesh.kumar@linux.vnet.ibm.com, shannon.zhao@linaro.org



On 13/03/2015 12:09, Shannon Zhao wrote:
> +    g_assert(strlen(path) < sizeof(helper.sun_path));

Ok.

>      sockfd = socket(AF_UNIX, SOCK_STREAM, 0);
>      if (sockfd < 0) {
>          fprintf(stderr, "failed to create socket: %s\n", strerror(errno));
>          return -1;
>      }
> -    strcpy(helper.sun_path, path);
> +    strncpy(helper.sun_path, path, sizeof(helper.sun_path));

strcpy is okay here.  strncpy makes people think of what happens if
strlen(path) == sizeof(helper.sun_path).  While this cannot happen here
because of the assertion, the function should still be used with care.

Paolo