Techwizz/kernel-fxtec-pro1x
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity

[NETFILTER]: ulog: fix panic on SMP kernels

Browse source 
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>
This commit is contained in:
Mark Huang 2006-08-13 18:57:54 -07:00 committed by David S. Miller
parent 0eff66e625
commit dcb7cd97f1
3 changed files with 11 additions and 0 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

3
net/bridge/netfilter/ebt_ulog.c
View file

@ -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;

5
net/ipv4/netfilter/ipt_ULOG.c
View file

@ -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;

3
net/netfilter/nfnetlink_log.c
View file

@ -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;