4.9-stable review patch. If anyone has any objections, please let me know.
------------------ From: jiangyiwen <[email protected]> commit 23cba9cbde0bba05d772b335fe5f66aa82b9ad19 upstream. Because the value of limit is VIRTQUEUE_NUM, if index is equal to limit, it will cause sg array out of bounds, so correct the judgement of BUG_ON. Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Yiwen Jiang <[email protected]> Reported-By: Dan Carpenter <[email protected]> Acked-by: Jun Piao <[email protected]> Cc: [email protected] Signed-off-by: Dominique Martinet <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- net/9p/trans_virtio.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/net/9p/trans_virtio.c +++ b/net/9p/trans_virtio.c @@ -189,7 +189,7 @@ static int pack_sg_list(struct scatterli s = rest_of_page(data); if (s > count) s = count; - BUG_ON(index > limit); + BUG_ON(index >= limit); /* Make sure we don't terminate early. */ sg_unmark_end(&sg[index]); sg_set_buf(&sg[index++], data, s); @@ -234,6 +234,7 @@ pack_sg_list_p(struct scatterlist *sg, i s = PAGE_SIZE - data_off; if (s > count) s = count; + BUG_ON(index >= limit); /* Make sure we don't terminate early. */ sg_unmark_end(&sg[index]); sg_set_page(&sg[index++], pdata[i++], s, data_off);
