diff options
author | Will Deacon <will.deacon@arm.com> | 2012-10-19 14:03:32 +0100 |
---|---|---|
committer | Ben Hutchings <ben@decadent.org.uk> | 2013-01-03 03:32:58 +0000 |
commit | 30d395b124c51db66d9f3ba0611cd62021afc392 (patch) | |
tree | dfed45d357b77a2116aa5a2b87c480413288273f /net | |
parent | 8bc528cece6bc1adf4524eaab7bb82aa66438c4a (diff) |
virtio: 9p: correctly pass physical address to userspace for high pages
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>
Diffstat (limited to 'net')
-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 32aa9834229..55f0c09da5a 100644 --- a/net/9p/trans_virtio.c +++ b/net/9p/trans_virtio.c @@ -37,6 +37,7 @@ #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> @@ -323,7 +324,7 @@ 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--; } |