From mboxrd@z Thu Jan 1 00:00:00 1970 From: Will Deacon Subject: [PATCH v2 2/3] virtio: 9p: correctly pass physical address to userspace for high pages Date: Fri, 19 Oct 2012 14:03:32 +0100 Message-ID: <1350651813-8694-2-git-send-email-will.deacon@arm.com> References: <1350651813-8694-1-git-send-email-will.deacon@arm.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1350651813-8694-1-git-send-email-will.deacon@arm.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: virtualization-bounces@lists.linux-foundation.org Errors-To: virtualization-bounces@lists.linux-foundation.org To: linux-kernel@vger.kernel.org Cc: Marc.Zyngier@arm.com, Will Deacon , virtualization@lists.linux-foundation.org, ericvh@gmail.com, levinsasha928@gmail.com, akpm@linux-foundation.org List-Id: virtualization@lists.linuxfoundation.org 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. Cc: Rusty Russell Cc: Sasha Levin Signed-off-by: Will Deacon --- net/9p/trans_virtio.c | 3 ++- 1 files changed, 2 insertions(+), 1 deletions(-) diff --git a/net/9p/trans_virtio.c b/net/9p/trans_virtio.c index 35b8911..fd05c81 100644 --- 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 virtio_chan *chan, 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--; } -- 1.7.4.1