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author | Johannes Berg <johannes@sipsolutions.net> | 2009-09-24 15:44:05 -0700 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2009-09-24 15:44:05 -0700 |
commit | b8273570f802a7658827dcb077b0b517ba75a289 (patch) | |
tree | 06fcee4433089cdb16504f40b1975ebbdf69e241 /net/netlink/af_netlink.c | |
parent | 704cc92e9ffe29458ea8831ae097c631b1160c01 (diff) | |
download | op-kernel-dev-b8273570f802a7658827dcb077b0b517ba75a289.zip op-kernel-dev-b8273570f802a7658827dcb077b0b517ba75a289.tar.gz |
genetlink: fix netns vs. netlink table locking (2)
Similar to commit d136f1bd366fdb7e747ca7e0218171e7a00a98a5,
there's a bug when unregistering a generic netlink family,
which is caught by the might_sleep() added in that commit:
BUG: sleeping function called from invalid context at net/netlink/af_netlink.c:183
in_atomic(): 1, irqs_disabled(): 0, pid: 1510, name: rmmod
2 locks held by rmmod/1510:
#0: (genl_mutex){+.+.+.}, at: [<ffffffff8138283b>] genl_unregister_family+0x2b/0x130
#1: (rcu_read_lock){.+.+..}, at: [<ffffffff8138270c>] __genl_unregister_mc_group+0x1c/0x120
Pid: 1510, comm: rmmod Not tainted 2.6.31-wl #444
Call Trace:
[<ffffffff81044ff9>] __might_sleep+0x119/0x150
[<ffffffff81380501>] netlink_table_grab+0x21/0x100
[<ffffffff813813a3>] netlink_clear_multicast_users+0x23/0x60
[<ffffffff81382761>] __genl_unregister_mc_group+0x71/0x120
[<ffffffff81382866>] genl_unregister_family+0x56/0x130
[<ffffffffa0007d85>] nl80211_exit+0x15/0x20 [cfg80211]
[<ffffffffa000005a>] cfg80211_exit+0x1a/0x40 [cfg80211]
Fix in the same way by grabbing the netlink table lock
before doing rcu_read_lock().
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/netlink/af_netlink.c')
-rw-r--r-- | net/netlink/af_netlink.c | 19 |
1 files changed, 11 insertions, 8 deletions
diff --git a/net/netlink/af_netlink.c b/net/netlink/af_netlink.c index 55180b9..a4bafbf 100644 --- a/net/netlink/af_netlink.c +++ b/net/netlink/af_netlink.c @@ -1609,6 +1609,16 @@ int netlink_change_ngroups(struct sock *sk, unsigned int groups) return err; } +void __netlink_clear_multicast_users(struct sock *ksk, unsigned int group) +{ + struct sock *sk; + struct hlist_node *node; + struct netlink_table *tbl = &nl_table[ksk->sk_protocol]; + + sk_for_each_bound(sk, node, &tbl->mc_list) + netlink_update_socket_mc(nlk_sk(sk), group, 0); +} + /** * netlink_clear_multicast_users - kick off multicast listeners * @@ -1619,15 +1629,8 @@ int netlink_change_ngroups(struct sock *sk, unsigned int groups) */ void netlink_clear_multicast_users(struct sock *ksk, unsigned int group) { - struct sock *sk; - struct hlist_node *node; - struct netlink_table *tbl = &nl_table[ksk->sk_protocol]; - netlink_table_grab(); - - sk_for_each_bound(sk, node, &tbl->mc_list) - netlink_update_socket_mc(nlk_sk(sk), group, 0); - + __netlink_clear_multicast_users(ksk, group); netlink_table_ungrab(); } |