From b9cdc88df8e63e81c723b82c286fc97f5d0dc325 Mon Sep 17 00:00:00 2001 From: Will Deacon Date: Fri, 19 Oct 2012 14:03:32 +0100 Subject: virtio: 9p: correctly pass physical address to userspace for high pages 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: stable@kernel.org Cc: Sasha Levin Signed-off-by: Will Deacon Signed-off-by: Rusty Russell --- net/9p/trans_virtio.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'net') diff --git a/net/9p/trans_virtio.c b/net/9p/trans_virtio.c index 35b8911b1c8e..fd05c81cb348 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--; } -- cgit v1.2.3