diff options
| author | Patrick McHardy <kaber@trash.net> | 2007-02-27 09:56:42 -0800 |
|---|---|---|
| committer | David S. Miller <davem@sunset.davemloft.net> | 2007-02-28 09:42:13 -0800 |
| commit | 4498121ca3acbf928681b71261227d28dc29b6f6 (patch) | |
| tree | f6947b8bf2cee22498fcea4e9c447c4eed4b6998 | |
| parent | 6548cda289b549ed60c35f16a0051609aeee2fd0 (diff) | |
| download | linux-3.10-4498121ca3acbf928681b71261227d28dc29b6f6.tar.gz linux-3.10-4498121ca3acbf928681b71261227d28dc29b6f6.tar.bz2 linux-3.10-4498121ca3acbf928681b71261227d28dc29b6f6.zip | |
[NET]: Handle disabled preemption in gfp_any()
ctnetlink uses netlink_unicast from an atomic_notifier_chain
(which is called within a RCU read side critical section)
without holding further locks. netlink_unicast calls netlink_trim
with the result of gfp_any() for the gfp flags, which are passed
down to pskb_expand_header. gfp_any() only checks for softirq
context and returns GFP_KERNEL, resulting in this warning:
BUG: sleeping function called from invalid context at mm/slab.c:3032
in_atomic():1, irqs_disabled():0
no locks held by rmmod/7010.
Call Trace:
[<ffffffff8109467f>] debug_show_held_locks+0x9/0xb
[<ffffffff8100b0b4>] __might_sleep+0xd9/0xdb
[<ffffffff810b5082>] __kmalloc+0x68/0x110
[<ffffffff811ba8f2>] pskb_expand_head+0x4d/0x13b
[<ffffffff81053147>] netlink_broadcast+0xa5/0x2e0
[<ffffffff881cd1d7>] :nfnetlink:nfnetlink_send+0x83/0x8a
[<ffffffff8834f6a6>] :nf_conntrack_netlink:ctnetlink_conntrack_event+0x94c/0x96a
[<ffffffff810624d6>] notifier_call_chain+0x29/0x3e
[<ffffffff8106251d>] atomic_notifier_call_chain+0x32/0x60
[<ffffffff881d266d>] :nf_conntrack:destroy_conntrack+0xa5/0x1d3
[<ffffffff881d194e>] :nf_conntrack:nf_ct_cleanup+0x8c/0x12c
[<ffffffff881d4614>] :nf_conntrack:kill_l3proto+0x0/0x13
[<ffffffff881d482a>] :nf_conntrack:nf_conntrack_l3proto_unregister+0x90/0x94
[<ffffffff883551b3>] :nf_conntrack_ipv4:nf_conntrack_l3proto_ipv4_fini+0x2b/0x5d
[<ffffffff8109d44f>] sys_delete_module+0x1b5/0x1e6
[<ffffffff8105f245>] trace_hardirqs_on_thunk+0x35/0x37
[<ffffffff8105911e>] system_call+0x7e/0x83
Since netlink_unicast is supposed to be callable from within RCU
read side critical sections, make gfp_any() check for in_atomic()
instead of in_softirq().
Additionally nfnetlink_send needs to use gfp_any() as well for the
call to netlink_broadcast).
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | include/net/sock.h | 2 | ||||
| -rw-r--r-- | net/netfilter/nfnetlink.c | 3 |
2 files changed, 2 insertions, 3 deletions
diff --git a/include/net/sock.h b/include/net/sock.h index 03684e702d1..2c7d60ca354 100644 --- a/include/net/sock.h +++ b/include/net/sock.h @@ -1278,7 +1278,7 @@ static inline int sock_writeable(const struct sock *sk) static inline gfp_t gfp_any(void) { - return in_softirq() ? GFP_ATOMIC : GFP_KERNEL; + return in_atomic() ? GFP_ATOMIC : GFP_KERNEL; } static inline long sock_rcvtimeo(const struct sock *sk, int noblock) diff --git a/net/netfilter/nfnetlink.c b/net/netfilter/nfnetlink.c index 11d504d0ac7..bf23e489e4c 100644 --- a/net/netfilter/nfnetlink.c +++ b/net/netfilter/nfnetlink.c @@ -197,13 +197,12 @@ EXPORT_SYMBOL_GPL(nfnetlink_has_listeners); int nfnetlink_send(struct sk_buff *skb, u32 pid, unsigned group, int echo) { - gfp_t allocation = in_interrupt() ? GFP_ATOMIC : GFP_KERNEL; int err = 0; NETLINK_CB(skb).dst_group = group; if (echo) atomic_inc(&skb->users); - netlink_broadcast(nfnl, skb, pid, group, allocation); + netlink_broadcast(nfnl, skb, pid, group, gfp_any()); if (echo) err = netlink_unicast(nfnl, skb, pid, MSG_DONTWAIT); |