diff options
| author | Will Deacon <will.deacon@arm.com> | 2012-10-19 15:03:32 +0200 |
|---|---|---|
| committer | Rusty Russell <rusty@rustcorp.com.au> | 2012-10-22 09:49:36 +0200 |
| commit | b9cdc88df8e63e81c723b82c286fc97f5d0dc325 (patch) | |
| tree | db52a74df7a5345f42250b7e82fb8f790820aab9 /net/9p | |
| parent | mm: highmem: export kmap_to_page for modules (diff) | |
| download | linux-b9cdc88df8e63e81c723b82c286fc97f5d0dc325.tar.xz linux-b9cdc88df8e63e81c723b82c286fc97f5d0dc325.zip | |
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 <levinsasha928@gmail.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Diffstat (limited to 'net/9p')
| -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 35b8911b1c8e..fd05c81cb348 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--; } |