diff options
| author | Mark Huang <mlhuang@cs.princeton.edu> | 2006-08-14 03:57:54 +0200 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2006-08-14 03:57:54 +0200 |
| commit | dcb7cd97f133f7cfbd181149a1e60215a869f895 (patch) | |
| tree | 73e600aa19051981a566ad55ca5fa6f9acec4f7a /net | |
| parent | [NETFILTER]: {arp,ip,ip6}_tables: proper error recovery in init path (diff) | |
| download | linux-dcb7cd97f133f7cfbd181149a1e60215a869f895.tar.xz linux-dcb7cd97f133f7cfbd181149a1e60215a869f895.zip | |
[NETFILTER]: ulog: fix panic on SMP kernels
Fix kernel panic on various SMP machines. The culprit is a null
ub->skb in ulog_send(). If ulog_timer() has already been scheduled on
one CPU and is spinning on the lock, and ipt_ulog_packet() flushes the
queue on another CPU by calling ulog_send() right before it exits,
there will be no skbuff when ulog_timer() acquires the lock and calls
ulog_send(). Cancelling the timer in ulog_send() doesn't help because
it has already been scheduled and is running on the first CPU.
Similar problem exists in ebt_ulog.c and nfnetlink_log.c.
Signed-off-by: Mark Huang <mlhuang@cs.princeton.edu>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net')
| -rw-r--r-- | net/bridge/netfilter/ebt_ulog.c | 3 | ||||
| -rw-r--r-- | net/ipv4/netfilter/ipt_ULOG.c | 5 | ||||
| -rw-r--r-- | net/netfilter/nfnetlink_log.c | 3 |
3 files changed, 11 insertions, 0 deletions
diff --git a/net/bridge/netfilter/ebt_ulog.c b/net/bridge/netfilter/ebt_ulog.c index 02693a230dc1..9f950db3b76f 100644 --- a/net/bridge/netfilter/ebt_ulog.c +++ b/net/bridge/netfilter/ebt_ulog.c @@ -74,6 +74,9 @@ static void ulog_send(unsigned int nlgroup) if (timer_pending(&ub->timer)) del_timer(&ub->timer); + if (!ub->skb) + return; + /* last nlmsg needs NLMSG_DONE */ if (ub->qlen > 1) ub->lastnlh->nlmsg_type = NLMSG_DONE; diff --git a/net/ipv4/netfilter/ipt_ULOG.c b/net/ipv4/netfilter/ipt_ULOG.c index d7dd7fe7051c..d46fd677fa11 100644 --- a/net/ipv4/netfilter/ipt_ULOG.c +++ b/net/ipv4/netfilter/ipt_ULOG.c @@ -115,6 +115,11 @@ static void ulog_send(unsigned int nlgroupnum) del_timer(&ub->timer); } + if (!ub->skb) { + DEBUGP("ipt_ULOG: ulog_send: nothing to send\n"); + return; + } + /* last nlmsg needs NLMSG_DONE */ if (ub->qlen > 1) ub->lastnlh->nlmsg_type = NLMSG_DONE; diff --git a/net/netfilter/nfnetlink_log.c b/net/netfilter/nfnetlink_log.c index 61cdda4e5d3b..b59d3b2bde21 100644 --- a/net/netfilter/nfnetlink_log.c +++ b/net/netfilter/nfnetlink_log.c @@ -366,6 +366,9 @@ __nfulnl_send(struct nfulnl_instance *inst) if (timer_pending(&inst->timer)) del_timer(&inst->timer); + if (!inst->skb) + return 0; + if (inst->qlen > 1) inst->lastnlh->nlmsg_type = NLMSG_DONE; |