5.15-stable review patch. If anyone has any objections, please let me know.
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From: Florian Westphal fw@strlen.de
[ Upstream commit 8aae7625ff3f0bd5484d01f1b8d5af82e44bec2d ]
New skbs allocated via nf_send_reset() have skb->dev == NULL.
fib*_rules_early_flow_dissect helpers already have a 'struct net' argument but its not passed down to the flow dissector core, which will then WARN as it can't derive a net namespace to use:
WARNING: CPU: 0 PID: 0 at net/core/flow_dissector.c:1016 __skb_flow_dissect+0xa91/0x1cd0 [..] ip_route_me_harder+0x143/0x330 nf_send_reset+0x17c/0x2d0 [nf_reject_ipv4] nft_reject_inet_eval+0xa9/0xf2 [nft_reject_inet] nft_do_chain+0x198/0x5d0 [nf_tables] nft_do_chain_inet+0xa4/0x110 [nf_tables] nf_hook_slow+0x41/0xc0 ip_local_deliver+0xce/0x110 ..
Cc: Stanislav Fomichev sdf@google.com Cc: David Ahern dsahern@kernel.org Cc: Ido Schimmel idosch@nvidia.com Fixes: 812fa71f0d96 ("netfilter: Dissect flow after packet mangling") Link: https://bugzilla.kernel.org/show_bug.cgi?id=217826 Signed-off-by: Florian Westphal fw@strlen.de Reviewed-by: Ido Schimmel idosch@nvidia.com Reviewed-by: David Ahern dsahern@kernel.org Link: https://lore.kernel.org/r/20230830110043.30497-1-fw@strlen.de Signed-off-by: Paolo Abeni pabeni@redhat.com Signed-off-by: Sasha Levin sashal@kernel.org --- include/net/ip6_fib.h | 5 ++++- include/net/ip_fib.h | 5 ++++- 2 files changed, 8 insertions(+), 2 deletions(-)
diff --git a/include/net/ip6_fib.h b/include/net/ip6_fib.h index bbb27639f2933..d72cee4dff70b 100644 --- a/include/net/ip6_fib.h +++ b/include/net/ip6_fib.h @@ -610,7 +610,10 @@ static inline bool fib6_rules_early_flow_dissect(struct net *net, if (!net->ipv6.fib6_rules_require_fldissect) return false;
- skb_flow_dissect_flow_keys(skb, flkeys, flag); + memset(flkeys, 0, sizeof(*flkeys)); + __skb_flow_dissect(net, skb, &flow_keys_dissector, + flkeys, NULL, 0, 0, 0, flag); + fl6->fl6_sport = flkeys->ports.src; fl6->fl6_dport = flkeys->ports.dst; fl6->flowi6_proto = flkeys->basic.ip_proto; diff --git a/include/net/ip_fib.h b/include/net/ip_fib.h index 3417ba2d27ad6..c3324a1949c3a 100644 --- a/include/net/ip_fib.h +++ b/include/net/ip_fib.h @@ -415,7 +415,10 @@ static inline bool fib4_rules_early_flow_dissect(struct net *net, if (!net->ipv4.fib_rules_require_fldissect) return false;
- skb_flow_dissect_flow_keys(skb, flkeys, flag); + memset(flkeys, 0, sizeof(*flkeys)); + __skb_flow_dissect(net, skb, &flow_keys_dissector, + flkeys, NULL, 0, 0, 0, flag); + fl4->fl4_sport = flkeys->ports.src; fl4->fl4_dport = flkeys->ports.dst; fl4->flowi4_proto = flkeys->basic.ip_proto;