Commit 36eeee75 authored by Kuniyuki Iwashima's avatar Kuniyuki Iwashima Committed by David S. Miller
Browse files

tcp: Fix a data-race around sysctl_tcp_adv_win_scale. 



While reading sysctl_tcp_adv_win_scale, it can be changed concurrently.
Thus, we need to add READ_ONCE() to its reader.

Fixes: 1da177e4 ("Linux-2.6.12-rc2")
Signed-off-by: default avatarKuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 02ca527a

include/net/tcp.h

+1 −1
Original line number Diff line number Diff line
@@ -1419,7 +1419,7 @@ void tcp_select_initial_window(const struct sock *sk, int __space, 


static inline int tcp_win_from_space(const struct sock *sk, int space)

{

	int tcp_adv_win_scale = sock_net(sk)->ipv4.sysctl_tcp_adv_win_scale;

	int tcp_adv_win_scale = READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_adv_win_scale);



	return tcp_adv_win_scale <= 0 ?

		(space>>(-tcp_adv_win_scale)) :