diff options
| author | Liping Zhang <zlpnobody@gmail.com> | 2017-05-21 17:38:11 +0300 |
|---|---|---|
| committer | Pablo Neira Ayuso <pablo@netfilter.org> | 2017-05-23 23:54:51 +0300 |
| commit | 124dffea9e8e372509e055aebd118e85518fd644 (patch) | |
| tree | eb35feb6b0c04851d32095b9aa082c0f898c9210 /net/netfilter | |
| parent | d2df92e98a34a5619dadd29c6291113c009181e7 (diff) | |
| download | linux-124dffea9e8e372509e055aebd118e85518fd644.tar.xz | |
netfilter: nat: use atomic bit op to clear the _SRC_NAT_DONE_BIT
We need to clear the IPS_SRC_NAT_DONE_BIT to indicate that the ct has
been removed from nat_bysource table. But unfortunately, we use the
non-atomic bit operation: "ct->status &= ~IPS_NAT_DONE_MASK". So
there's a race condition that we may clear the _DYING_BIT set by
another CPU unexpectedly.
Since we don't care about the IPS_DST_NAT_DONE_BIT, so just using
clear_bit to clear the IPS_SRC_NAT_DONE_BIT is enough.
Also note, this is the last user which use the non-atomic bit operation
to update the confirmed ct->status.
Reported-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Liping Zhang <zlpnobody@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Diffstat (limited to 'net/netfilter')
| -rw-r--r-- | net/netfilter/nf_nat_core.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/net/netfilter/nf_nat_core.c b/net/netfilter/nf_nat_core.c index ef0be325a0c6..6c72922d20ca 100644 --- a/net/netfilter/nf_nat_core.c +++ b/net/netfilter/nf_nat_core.c @@ -566,7 +566,7 @@ static int nf_nat_proto_clean(struct nf_conn *ct, void *data) * Else, when the conntrack is destoyed, nf_nat_cleanup_conntrack() * will delete entry from already-freed table. */ - ct->status &= ~IPS_NAT_DONE_MASK; + clear_bit(IPS_SRC_NAT_DONE_BIT, &ct->status); rhltable_remove(&nf_nat_bysource_table, &ct->nat_bysource, nf_nat_bysource_params); |