diff options
| author | Patrick McHardy <kaber@trash.net> | 2008-06-17 22:51:47 (GMT) |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2008-06-17 22:51:47 (GMT) |
| commit | 68b80f11380889996aa7eadba29dbbb5c29a5864 (patch) | |
| tree | e6425d1ee4d15713678e60cd03bd5f514385e6e5 /net/ipv4 | |
| parent | 65c3e4715b1b934f8dcc002d9f46b4371ca7a9b1 (diff) | |
| download | linux-68b80f11380889996aa7eadba29dbbb5c29a5864.tar.xz | |
netfilter: nf_nat: fix RCU races
Fix three ct_extend/NAT extension related races:
- When cleaning up the extension area and removing it from the bysource hash,
the nat->ct pointer must not be set to NULL since it may still be used in
a RCU read side
- When replacing a NAT extension area in the bysource hash, the nat->ct
pointer must be assigned before performing the replacement
- When reallocating extension storage in ct_extend, the old memory must
not be freed immediately since it may still be used by a RCU read side
Possibly fixes https://bugzilla.redhat.com/show_bug.cgi?id=449315
and/or http://bugzilla.kernel.org/show_bug.cgi?id=10875
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv4')
| -rw-r--r-- | net/ipv4/netfilter/nf_nat_core.c | 3 |
1 files changed, 1 insertions, 2 deletions
diff --git a/net/ipv4/netfilter/nf_nat_core.c b/net/ipv4/netfilter/nf_nat_core.c index 0457859..d2a887f 100644 --- a/net/ipv4/netfilter/nf_nat_core.c +++ b/net/ipv4/netfilter/nf_nat_core.c @@ -556,7 +556,6 @@ static void nf_nat_cleanup_conntrack(struct nf_conn *ct) spin_lock_bh(&nf_nat_lock); hlist_del_rcu(&nat->bysource); - nat->ct = NULL; spin_unlock_bh(&nf_nat_lock); } @@ -570,8 +569,8 @@ static void nf_nat_move_storage(void *new, void *old) return; spin_lock_bh(&nf_nat_lock); - hlist_replace_rcu(&old_nat->bysource, &new_nat->bysource); new_nat->ct = ct; + hlist_replace_rcu(&old_nat->bysource, &new_nat->bysource); spin_unlock_bh(&nf_nat_lock); } |