[PATCH 0/4] netlink: bridge: fix nf_bridge->physindev use after free

From: Pavel Tikhomirov
Date: Wed Jan 10 2024 - 06:05:30 EST


Code processing skb from neigh->arp_queue can access its
nf_bridge->physindev, which can already be freed, leading to crash.

So, as Florian suggests, we can put physinif on nf_bridge and peek into
the original device with dev_get_by_index_rcu(), so that we can be sure
that device is not freed under us.

This is a second attempt to fix this issue, first attempt:

"neighbour: purge nf_bridged skb from foreign device neigh"
https://lore.kernel.org/netdev/20240108085232.95437-1-ptikhomirov@xxxxxxxxxxxxx/

Pavel Tikhomirov (4):
netfilter: nfnetlink_log: use proper helper for fetching physinif
netfilter: nf_queue: remove excess nf_bridge variable
netfilter: propagate net to nf_bridge_get_physindev
netfilter: bridge: replace physindev with physinif in nf_bridge_info

include/linux/netfilter_bridge.h | 6 ++--
include/linux/skbuff.h | 2 +-
net/bridge/br_netfilter_hooks.c | 42 +++++++++++++++++-----
net/bridge/br_netfilter_ipv6.c | 14 +++++---
net/ipv4/netfilter/nf_reject_ipv4.c | 9 +++--
net/ipv6/netfilter/nf_reject_ipv6.c | 11 ++++--
net/netfilter/ipset/ip_set_hash_netiface.c | 8 ++---
net/netfilter/nf_log_syslog.c | 13 +++----
net/netfilter/nf_queue.c | 6 ++--
net/netfilter/nfnetlink_log.c | 13 +++----
net/netfilter/xt_physdev.c | 2 +-
11 files changed, 83 insertions(+), 43 deletions(-)

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2.43.0