alistair23-linux/net/ipv6/udp_impl.h
Eric Dumazet f77d602124 ipv6: do not clear pinet6 field
We have seen multiple NULL dereferences in __inet6_lookup_established()

After analysis, I found that inet6_sk() could be NULL while the
check for sk_family == AF_INET6 was true.

Bug was added in linux-2.6.29 when RCU lookups were introduced in UDP
and TCP stacks.

Once an IPv6 socket, using SLAB_DESTROY_BY_RCU is inserted in a hash
table, we no longer can clear pinet6 field.

This patch extends logic used in commit fcbdf09d96
("net: fix nulls list corruptions in sk_prot_alloc")

TCP/UDP/UDPLite IPv6 protocols provide their own .clear_sk() method
to make sure we do not clear pinet6 field.

At socket clone phase, we do not really care, as cloning the parent (non
NULL) pinet6 is not adding a fatal race.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-05-11 16:26:38 -07:00

40 lines
1.5 KiB
C

#ifndef _UDP6_IMPL_H
#define _UDP6_IMPL_H
#include <net/udp.h>
#include <net/udplite.h>
#include <net/protocol.h>
#include <net/addrconf.h>
#include <net/inet_common.h>
#include <net/transp_v6.h>
extern int __udp6_lib_rcv(struct sk_buff *, struct udp_table *, int );
extern void __udp6_lib_err(struct sk_buff *, struct inet6_skb_parm *,
u8 , u8 , int , __be32 , struct udp_table *);
extern int udp_v6_get_port(struct sock *sk, unsigned short snum);
extern int udpv6_getsockopt(struct sock *sk, int level, int optname,
char __user *optval, int __user *optlen);
extern int udpv6_setsockopt(struct sock *sk, int level, int optname,
char __user *optval, unsigned int optlen);
#ifdef CONFIG_COMPAT
extern int compat_udpv6_setsockopt(struct sock *sk, int level, int optname,
char __user *optval, unsigned int optlen);
extern int compat_udpv6_getsockopt(struct sock *sk, int level, int optname,
char __user *optval, int __user *optlen);
#endif
extern int udpv6_sendmsg(struct kiocb *iocb, struct sock *sk,
struct msghdr *msg, size_t len);
extern int udpv6_recvmsg(struct kiocb *iocb, struct sock *sk,
struct msghdr *msg, size_t len,
int noblock, int flags, int *addr_len);
extern int udpv6_queue_rcv_skb(struct sock * sk, struct sk_buff *skb);
extern void udpv6_destroy_sock(struct sock *sk);
extern void udp_v6_clear_sk(struct sock *sk, int size);
#ifdef CONFIG_PROC_FS
extern int udp6_seq_show(struct seq_file *seq, void *v);
#endif
#endif /* _UDP6_IMPL_H */