diff mbox series

xsk: fix out of boundary write in __xsk_rcv_memcpy

Message ID 1585813930-19712-1-git-send-email-lirongqing@baidu.com
State New
Headers show
Series xsk: fix out of boundary write in __xsk_rcv_memcpy | expand

Commit Message

Li RongQing April 2, 2020, 7:52 a.m. UTC 
first_len is remainder of first page, if write size is
larger than it, out of page boundary write will happen

Fixes: c05cd3645814 "(xsk: add support to allow unaligned chunk placement)"
Signed-off-by: Li RongQing <lirongqing@baidu.com>
---
 net/xdp/xsk.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)
diff mbox series

Patch

diff --git a/net/xdp/xsk.c b/net/xdp/xsk.c
index 356f90e4522b..c350108aa38d 100644
--- a/net/xdp/xsk.c
+++ b/net/xdp/xsk.c
@@ -131,8 +131,9 @@  static void __xsk_rcv_memcpy(struct xdp_umem *umem, u64 addr, void *from_buf,
 		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;
 	}