forge/linux-pinenote
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

ip: ip_ra_control() rcu fix

Browse source 
commit 66018506e1 (ip: Router Alert RCU conversion) introduced RCU
lookups to ip_call_ra_chain(). It missed proper deinit phase :
When ip_ra_control() deletes an ip_ra_chain, it should make sure
ip_call_ra_chain() users can not start to use socket during the rcu
grace period. It should also delay the sock_put() after the grace
period, or we risk a premature socket freeing and corruptions, as
raw sockets are not rcu protected yet.

This delay avoids using expensive atomic_inc_not_zero() in
ip_call_ra_chain().

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Eric Dumazet 2010-06-09 16:21:07 +00:00 • committed by David S. Miller
parent 96b52e61be
commit 592fcb9dfa
2 changed files with 19 additions and 5 deletions
Download patch file Download diff file Expand all files Collapse all files

5
include/net/ip.h
View file

@ -61,7 +61,10 @@ struct ipcm_cookie {
struct ip_ra_chain {
struct ip_ra_chain *next;
struct sock *sk;
void (*destructor)(struct sock *);
union {
void (*destructor)(struct sock *);
struct sock *saved_sk;
};
struct rcu_head rcu;
};