diff options
| author | Will Deacon <will.deacon@arm.com> | 2012-10-19 14:03:32 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2014-06-11 12:04:17 -0700 |
| commit | 6330a0c429c1518714283be51b86dc02b45db882 (patch) | |
| tree | 0741c1546b3580d3d7e519d568a3e47734a678ba | |
| parent | ad988bcb5b18ad5e1865f638cfc7ba3e600c4d46 (diff) | |
virtio: 9p: correctly pass physical address to userspace for high pages
commit 30d395b124c51db66d9f3ba0611cd62021afc392 upstream.
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.
Cc: Sasha Levin <levinsasha928@gmail.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | 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 052d343d43ff..9f4fcc5419e5 100644 --- a/net/9p/trans_virtio.c +++ b/net/9p/trans_virtio.c @@ -39,6 +39,7 @@ #include <linux/inet.h> #include <linux/idr.h> #include <linux/file.h> +#include <linux/highmem.h> #include <linux/slab.h> #include <net/9p/9p.h> #include <linux/parser.h> @@ -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--; } |