From 3610cda53f247e176bcbb7a7cca64bc53b12acdb Mon Sep 17 00:00:00 2001 From: "David S. Miller" Date: Wed, 5 Jan 2011 15:38:53 -0800 Subject: af_unix: Avoid socket->sk NULL OOPS in stream connect security hooks. unix_release() can asynchornously set socket->sk to NULL, and it does so without holding the unix_state_lock() on "other" during stream connects. However, the reverse mapping, sk->sk_socket, is only transitioned to NULL under the unix_state_lock(). Therefore make the security hooks follow the reverse mapping instead of the forward mapping. Reported-by: Jeremy Fitzhardinge Reported-by: Linus Torvalds Signed-off-by: David S. Miller --- include/linux/security.h | 15 +++++++-------- 1 file changed, 7 insertions(+), 8 deletions(-) (limited to 'include') diff --git a/include/linux/security.h b/include/linux/security.h index fd4d55fb8845..d47a4c24b3e4 100644 --- a/include/linux/security.h +++ b/include/linux/security.h @@ -796,8 +796,9 @@ static inline void security_free_mnt_opts(struct security_mnt_opts *opts) * @unix_stream_connect: * Check permissions before establishing a Unix domain stream connection * between @sock and @other. - * @sock contains the socket structure. - * @other contains the peer socket structure. + * @sock contains the sock structure. + * @other contains the peer sock structure. + * @newsk contains the new sock structure. * Return 0 if permission is granted. * @unix_may_send: * Check permissions before connecting or sending datagrams from @sock to @@ -1568,8 +1569,7 @@ struct security_operations { int (*inode_getsecctx)(struct inode *inode, void **ctx, u32 *ctxlen); #ifdef CONFIG_SECURITY_NETWORK - int (*unix_stream_connect) (struct socket *sock, - struct socket *other, struct sock *newsk); + int (*unix_stream_connect) (struct sock *sock, struct sock *other, struct sock *newsk); int (*unix_may_send) (struct socket *sock, struct socket *other); int (*socket_create) (int family, int type, int protocol, int kern); @@ -2525,8 +2525,7 @@ static inline int security_inode_getsecctx(struct inode *inode, void **ctx, u32 #ifdef CONFIG_SECURITY_NETWORK -int security_unix_stream_connect(struct socket *sock, struct socket *other, - struct sock *newsk); +int security_unix_stream_connect(struct sock *sock, struct sock *other, struct sock *newsk); int security_unix_may_send(struct socket *sock, struct socket *other); int security_socket_create(int family, int type, int protocol, int kern); int security_socket_post_create(struct socket *sock, int family, @@ -2567,8 +2566,8 @@ void security_tun_dev_post_create(struct sock *sk); int security_tun_dev_attach(struct sock *sk); #else /* CONFIG_SECURITY_NETWORK */ -static inline int security_unix_stream_connect(struct socket *sock, - struct socket *other, +static inline int security_unix_stream_connect(struct sock *sock, + struct sock *other, struct sock *newsk) { return 0; -- cgit v1.2.2