From: Li RongQing lirongqing@baidu.com
commit db5c97f02373917efe2c218ebf8e3d8b19e343b6 upstream.
first_len is the remainder of the first page we're copying. If this size is larger, then out of page boundary write will otherwise happen.
Fixes: c05cd3645814 ("xsk: add support to allow unaligned chunk placement") Signed-off-by: Li RongQing lirongqing@baidu.com Signed-off-by: Daniel Borkmann daniel@iogearbox.net Acked-by: Jonathan Lemon jonathan.lemon@gmail.com Acked-by: Björn Töpel bjorn.topel@intel.com Link: https://lore.kernel.org/bpf/1585813930-19712-1-git-send-email-lirongqing@bai... Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- net/xdp/xsk.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-)
--- a/net/xdp/xsk.c +++ b/net/xdp/xsk.c @@ -129,8 +129,9 @@ static void __xsk_rcv_memcpy(struct xdp_ u64 page_start = addr & ~(PAGE_SIZE - 1); u64 first_len = PAGE_SIZE - (addr - page_start);
- memcpy(to_buf, from_buf, first_len + metalen); - memcpy(next_pg_addr, from_buf + first_len, len - first_len); + memcpy(to_buf, from_buf, first_len); + memcpy(next_pg_addr, from_buf + first_len, + len + metalen - first_len);
return; }