diff options
author | Eric Dumazet <eric.dumazet@gmail.com> | 2011-04-21 05:45:37 -0400 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2011-04-28 16:16:35 -0400 |
commit | f6d8bd051c391c1c0458a30b2a7abcd939329259 (patch) | |
tree | 1dc4daecdeb0b42c2c6b59d7d6b41e091c11db5f /include/net/ip.h | |
parent | 0a14842f5a3c0e88a1e59fac5c3025db39721f74 (diff) |
inet: add RCU protection to inet->opt
We lack proper synchronization to manipulate inet->opt ip_options
Problem is ip_make_skb() calls ip_setup_cork() and
ip_setup_cork() possibly makes a copy of ipc->opt (struct ip_options),
without any protection against another thread manipulating inet->opt.
Another thread can change inet->opt pointer and free old one under us.
Use RCU to protect inet->opt (changed to inet->inet_opt).
Instead of handling atomic refcounts, just copy ip_options when
necessary, to avoid cache line dirtying.
We cant insert an rcu_head in struct ip_options since its included in
skb->cb[], so this patch is large because I had to introduce a new
ip_options_rcu structure.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'include/net/ip.h')
-rw-r--r-- | include/net/ip.h | 11 |
1 files changed, 6 insertions, 5 deletions
diff --git a/include/net/ip.h b/include/net/ip.h index 7c416583b710..3a59bf99aa3a 100644 --- a/include/net/ip.h +++ b/include/net/ip.h | |||
@@ -52,7 +52,7 @@ static inline unsigned int ip_hdrlen(const struct sk_buff *skb) | |||
52 | struct ipcm_cookie { | 52 | struct ipcm_cookie { |
53 | __be32 addr; | 53 | __be32 addr; |
54 | int oif; | 54 | int oif; |
55 | struct ip_options *opt; | 55 | struct ip_options_rcu *opt; |
56 | __u8 tx_flags; | 56 | __u8 tx_flags; |
57 | }; | 57 | }; |
58 | 58 | ||
@@ -92,7 +92,7 @@ extern int igmp_mc_proc_init(void); | |||
92 | 92 | ||
93 | extern int ip_build_and_send_pkt(struct sk_buff *skb, struct sock *sk, | 93 | extern int ip_build_and_send_pkt(struct sk_buff *skb, struct sock *sk, |
94 | __be32 saddr, __be32 daddr, | 94 | __be32 saddr, __be32 daddr, |
95 | struct ip_options *opt); | 95 | struct ip_options_rcu *opt); |
96 | extern int ip_rcv(struct sk_buff *skb, struct net_device *dev, | 96 | extern int ip_rcv(struct sk_buff *skb, struct net_device *dev, |
97 | struct packet_type *pt, struct net_device *orig_dev); | 97 | struct packet_type *pt, struct net_device *orig_dev); |
98 | extern int ip_local_deliver(struct sk_buff *skb); | 98 | extern int ip_local_deliver(struct sk_buff *skb); |
@@ -416,14 +416,15 @@ extern int ip_forward(struct sk_buff *skb); | |||
416 | * Functions provided by ip_options.c | 416 | * Functions provided by ip_options.c |
417 | */ | 417 | */ |
418 | 418 | ||
419 | extern void ip_options_build(struct sk_buff *skb, struct ip_options *opt, __be32 daddr, struct rtable *rt, int is_frag); | 419 | extern void ip_options_build(struct sk_buff *skb, struct ip_options *opt, |
420 | __be32 daddr, struct rtable *rt, int is_frag); | ||
420 | extern int ip_options_echo(struct ip_options *dopt, struct sk_buff *skb); | 421 | extern int ip_options_echo(struct ip_options *dopt, struct sk_buff *skb); |
421 | extern void ip_options_fragment(struct sk_buff *skb); | 422 | extern void ip_options_fragment(struct sk_buff *skb); |
422 | extern int ip_options_compile(struct net *net, | 423 | extern int ip_options_compile(struct net *net, |
423 | struct ip_options *opt, struct sk_buff *skb); | 424 | struct ip_options *opt, struct sk_buff *skb); |
424 | extern int ip_options_get(struct net *net, struct ip_options **optp, | 425 | extern int ip_options_get(struct net *net, struct ip_options_rcu **optp, |
425 | unsigned char *data, int optlen); | 426 | unsigned char *data, int optlen); |
426 | extern int ip_options_get_from_user(struct net *net, struct ip_options **optp, | 427 | extern int ip_options_get_from_user(struct net *net, struct ip_options_rcu **optp, |
427 | unsigned char __user *data, int optlen); | 428 | unsigned char __user *data, int optlen); |
428 | extern void ip_options_undo(struct ip_options * opt); | 429 | extern void ip_options_undo(struct ip_options * opt); |
429 | extern void ip_forward_options(struct sk_buff *skb); | 430 | extern void ip_forward_options(struct sk_buff *skb); |