remarkable-linux/net/rds/tcp.h
David S. Miller 676d23690f net: Fix use after free by removing length arg from sk_data_ready callbacks.
Several spots in the kernel perform a sequence like:

	skb_queue_tail(&sk->s_receive_queue, skb);
	sk->sk_data_ready(sk, skb->len);

But at the moment we place the SKB onto the socket receive queue it
can be consumed and freed up.  So this skb->len access is potentially
to freed up memory.

Furthermore, the skb->len can be modified by the consumer so it is
possible that the value isn't accurate.

And finally, no actual implementation of this callback actually uses
the length argument.  And since nobody actually cared about it's
value, lots of call sites pass arbitrary values in such as '0' and
even '1'.

So just remove the length argument from the callback, that way there
is no confusion whatsoever and all of these use-after-free cases get
fixed as a side effect.

Based upon a patch by Eric Dumazet and his suggestion to audit this
issue tree-wide.

Signed-off-by: David S. Miller <davem@davemloft.net>
2014-04-11 16:15:36 -04:00

89 lines
2.5 KiB
C

#ifndef _RDS_TCP_H
#define _RDS_TCP_H
#define RDS_TCP_PORT 16385
struct rds_tcp_incoming {
struct rds_incoming ti_inc;
struct sk_buff_head ti_skb_list;
};
struct rds_tcp_connection {
struct list_head t_tcp_node;
struct rds_connection *conn;
struct socket *t_sock;
void *t_orig_write_space;
void *t_orig_data_ready;
void *t_orig_state_change;
struct rds_tcp_incoming *t_tinc;
size_t t_tinc_hdr_rem;
size_t t_tinc_data_rem;
/* XXX error report? */
struct work_struct t_conn_w;
struct work_struct t_send_w;
struct work_struct t_down_w;
struct work_struct t_recv_w;
/* for info exporting only */
struct list_head t_list_item;
u32 t_last_sent_nxt;
u32 t_last_expected_una;
u32 t_last_seen_una;
};
struct rds_tcp_statistics {
uint64_t s_tcp_data_ready_calls;
uint64_t s_tcp_write_space_calls;
uint64_t s_tcp_sndbuf_full;
uint64_t s_tcp_connect_raced;
uint64_t s_tcp_listen_closed_stale;
};
/* tcp.c */
void rds_tcp_tune(struct socket *sock);
void rds_tcp_nonagle(struct socket *sock);
void rds_tcp_set_callbacks(struct socket *sock, struct rds_connection *conn);
void rds_tcp_restore_callbacks(struct socket *sock,
struct rds_tcp_connection *tc);
u32 rds_tcp_snd_nxt(struct rds_tcp_connection *tc);
u32 rds_tcp_snd_una(struct rds_tcp_connection *tc);
u64 rds_tcp_map_seq(struct rds_tcp_connection *tc, u32 seq);
extern struct rds_transport rds_tcp_transport;
/* tcp_connect.c */
int rds_tcp_conn_connect(struct rds_connection *conn);
void rds_tcp_conn_shutdown(struct rds_connection *conn);
void rds_tcp_state_change(struct sock *sk);
/* tcp_listen.c */
int rds_tcp_listen_init(void);
void rds_tcp_listen_stop(void);
void rds_tcp_listen_data_ready(struct sock *sk);
/* tcp_recv.c */
int rds_tcp_recv_init(void);
void rds_tcp_recv_exit(void);
void rds_tcp_data_ready(struct sock *sk);
int rds_tcp_recv(struct rds_connection *conn);
void rds_tcp_inc_free(struct rds_incoming *inc);
int rds_tcp_inc_copy_to_user(struct rds_incoming *inc, struct iovec *iov,
size_t size);
/* tcp_send.c */
void rds_tcp_xmit_prepare(struct rds_connection *conn);
void rds_tcp_xmit_complete(struct rds_connection *conn);
int rds_tcp_xmit(struct rds_connection *conn, struct rds_message *rm,
unsigned int hdr_off, unsigned int sg, unsigned int off);
void rds_tcp_write_space(struct sock *sk);
/* tcp_stats.c */
DECLARE_PER_CPU(struct rds_tcp_statistics, rds_tcp_stats);
#define rds_tcp_stats_inc(member) rds_stats_inc_which(rds_tcp_stats, member)
unsigned int rds_tcp_stats_info_copy(struct rds_info_iterator *iter,
unsigned int avail);
#endif