From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Greg Kroah-Hartman , alan@lxorguk.ukuu.org.uk, Will Deacon , Sasha Levin , Rusty Russell Subject: [ 013/123] virtio: 9p: correctly pass physical address to userspace for high pages Date: Wed, 9 Jan 2013 12:34:12 -0800 Message-Id: <20130109201500.230166296@linuxfoundation.org> In-Reply-To: <20130109201458.392601412@linuxfoundation.org> References: <20130109201458.392601412@linuxfoundation.org> List-ID: 3.7-stable review patch. If anyone has any objections, please let me know. ------------------ From: Will Deacon commit b9cdc88df8e63e81c723b82c286fc97f5d0dc325 upstream. When using a virtio transport, the 9p net device may pass the physical address of a kernel buffer to userspace via a scatterlist inside a virtqueue. If the kernel buffer is mapped outside of the linear mapping (e.g. highmem), then virt_to_page will return a bogus value and we will populate the scatterlist with junk. This patch uses kmap_to_page when populating the page array for a kernel buffer. Signed-off-by: Will Deacon Cc: Sasha Levin Signed-off-by: Rusty Russell Signed-off-by: Greg Kroah-Hartman --- net/9p/trans_virtio.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/net/9p/trans_virtio.c +++ b/net/9p/trans_virtio.c @@ -39,6 +39,7 @@ #include #include #include +#include #include #include #include @@ -325,7 +326,7 @@ static int p9_get_mapped_pages(struct vi int count = nr_pages; while (nr_pages) { s = rest_of_page(data); - pages[index++] = virt_to_page(data); + pages[index++] = kmap_to_page(data); data += s; nr_pages--; }