TencentOS-kernel/net/core
Jesper Dangaard Brouer c693e2e790 bpf: Fix bpf_fib_lookup helper MTU check for SKB ctx
[ Upstream commit 2c0a10af688c02adcf127aad29e923e0056c6b69 ]

BPF end-user on Cilium slack-channel (Carlo Carraro) wants to use
bpf_fib_lookup for doing MTU-check, but *prior* to extending packet size,
by adjusting fib_params 'tot_len' with the packet length plus the expected
encap size. (Just like the bpf_check_mtu helper supports). He discovered
that for SKB ctx the param->tot_len was not used, instead skb->len was used
(via MTU check in is_skb_forwardable() that checks against netdev MTU).

Fix this by using fib_params 'tot_len' for MTU check. If not provided (e.g.
zero) then keep existing TC behaviour intact. Notice that 'tot_len' for MTU
check is done like XDP code-path, which checks against FIB-dst MTU.

V16:
- Revert V13 optimization, 2nd lookup is against egress/resulting netdev

V13:
- Only do ifindex lookup one time, calling dev_get_by_index_rcu().

V10:
- Use same method as XDP for 'tot_len' MTU check

Fixes: 4c79579b44b1 ("bpf: Change bpf_fib_lookup to return lookup status")
Reported-by: Carlo Carraro <colrack@gmail.com>
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/161287789444.790810.15247494756551413508.stgit@firesoul
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-04-12 12:52:15 +08:00
..
Makefile Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
bpf_sk_storage.c bpf: Switch bpf_map ref counter to atomic64_t so bpf_map_inc() never fails 2021-03-16 16:43:58 +08:00
datagram.c udp: fix skb_copy_and_csum_datagram with odd segment sizes 2021-04-12 12:52:05 +08:00
datagram.h Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
dev.c net: gro: do not keep too many GRO packets in napi->rx_list 2021-04-12 12:52:06 +08:00
dev_addr_lists.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
dev_ioctl.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
devlink.c devlink: Hold rtnl lock while reading netdev attributes 2021-03-16 16:41:51 +08:00
drop_monitor.c drop_monitor: work around gcc-10 stringop-overflow warning 2021-03-16 16:27:46 +08:00
dst.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
dst_cache.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
ethtool.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
failover.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
fib_notifier.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
fib_rules.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
filter.c bpf: Fix bpf_fib_lookup helper MTU check for SKB ctx 2021-04-12 12:52:15 +08:00
flow_dissector.c flow_dissector: Drop BPF flow dissector prog ref on netns cleanup 2021-03-16 16:28:20 +08:00
flow_offload.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
gen_estimator.c net_sched: gen_estimator: support large ewma log 2021-04-12 12:51:50 +08:00
gen_stats.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
gro_cells.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
hwbm.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
link_watch.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
lwt_bpf.c lwt: Disable BH too in run_lwt_bpf() 2021-03-16 16:43:20 +08:00
lwtunnel.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
neighbour.c neighbour: Prevent a dead entry from updating gc_list 2021-04-12 12:51:58 +08:00
net-procfs.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
net-sysfs.c net-sysfs: take the rtnl lock when accessing xps_rxqs_map and num_tc 2021-04-12 12:51:08 +08:00
net-sysfs.h Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
net-traces.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
net_namespace.c merge bpf_get_netns_cookie from f318903c0bf42448b4c884732df2bbb0ef7a2284. 2021-03-16 16:43:59 +08:00
netclassid_cgroup.c cgroup, netclassid: remove double cond_resched 2021-03-16 16:27:30 +08:00
netevent.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
netpoll.c net: Have netpoll bring-up DSA management interface 2021-03-16 16:41:06 +08:00
netprio_cgroup.c netprio_cgroup: Fix unlimited memory leak of v2 cgroups 2021-03-16 16:27:49 +08:00
page_pool.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
pktgen.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
ptp_classifier.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
request_sock.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
rtnetlink.c rtnetlink: Fix memory(net_device) leak when ->newlink fails 2021-03-16 16:32:42 +08:00
scm.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
secure_seq.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
skbuff.c skbuff: back tiny skbs with kmalloc() in __netdev_alloc_skb() too 2021-04-12 12:51:39 +08:00
skmsg.c bpf, sockmap: Avoid returning unneeded EAGAIN when redirecting to self 2021-03-16 16:41:24 +08:00
sock.c socket: don't clear SOCK_TSTAMP_NEW when SO_TIMESTAMPNS is disabled 2021-03-16 16:39:27 +08:00
sock_diag.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
sock_map.c bpf: sockmap: Require attach_bpf_fd when detaching a program 2021-03-16 16:32:59 +08:00
sock_reuseport.c udp: Prevent reuseport_select_sock from reading uninitialized socks 2021-04-12 12:51:29 +08:00
stream.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
sysctl_net_core.c bpf: Check correct cred for CAP_SYSLOG in bpf_dump_raw_ok() 2021-03-16 16:31:38 +08:00
timestamping.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
tso.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
utils.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
xdp.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00