linux-stable.git/net, branch v5.4.249

sch_netem: acquire qdisc lock in netem_change()

2023-06-28T08:18:40+00:00

[ Upstream commit 2174a08db80d1efeea382e25ac41c4e7511eb6d6 ]

syzbot managed to trigger a divide error [1] in netem.

It could happen if q->rate changes while netem_enqueue()
is running, since q->rate is read twice.

It turns out netem_change() always lacked proper synchronization.

[1]
divide error: 0000 [#1] SMP KASAN
CPU: 1 PID: 7867 Comm: syz-executor.1 Not tainted 6.1.30-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/25/2023
RIP: 0010:div64_u64 include/linux/math64.h:69 [inline]
RIP: 0010:packet_time_ns net/sched/sch_netem.c:357 [inline]
RIP: 0010:netem_enqueue+0x2067/0x36d0 net/sched/sch_netem.c:576
Code: 89 e2 48 69 da 00 ca 9a 3b 42 80 3c 28 00 4c 8b a4 24 88 00 00 00 74 0d 4c 89 e7 e8 c3 4f 3b fd 48 8b 4c 24 18 48 89 d8 31 d2 <49> f7 34 24 49 01 c7 4c 8b 64 24 48 4d 01 f7 4c 89 e3 48 c1 eb 03
RSP: 0018:ffffc9000dccea60 EFLAGS: 00010246
RAX: 000001a442624200 RBX: 000001a442624200 RCX: ffff888108a4f000
RDX: 0000000000000000 RSI: 000000000000070d RDI: 000000000000070d
RBP: ffffc9000dcceb90 R08: ffffffff849c5e26 R09: fffffbfff10e1297
R10: 0000000000000000 R11: dffffc0000000001 R12: ffff888108a4f358
R13: dffffc0000000000 R14: 0000001a8cd9a7ec R15: 0000000000000000
FS: 00007fa73fe18700(0000) GS:ffff8881f6b00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fa73fdf7718 CR3: 000000011d36e000 CR4: 0000000000350ee0
Call Trace:

[] __dev_xmit_skb net/core/dev.c:3931 [inline]
[] __dev_queue_xmit+0xcf5/0x3370 net/core/dev.c:4290
[] dev_queue_xmit include/linux/netdevice.h:3030 [inline]
[] neigh_hh_output include/net/neighbour.h:531 [inline]
[] neigh_output include/net/neighbour.h:545 [inline]
[] ip_finish_output2+0xb92/0x10d0 net/ipv4/ip_output.c:235
[] __ip_finish_output+0xc3/0x2b0
[] ip_finish_output+0x31/0x2a0 net/ipv4/ip_output.c:323
[] NF_HOOK_COND include/linux/netfilter.h:298 [inline]
[] ip_output+0x224/0x2a0 net/ipv4/ip_output.c:437
[] dst_output include/net/dst.h:444 [inline]
[] ip_local_out net/ipv4/ip_output.c:127 [inline]
[] __ip_queue_xmit+0x1425/0x2000 net/ipv4/ip_output.c:542
[] ip_queue_xmit+0x4c/0x70 net/ipv4/ip_output.c:556

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Reported-by: syzbot 
Signed-off-by: Eric Dumazet 
Cc: Stephen Hemminger 
Cc: Jamal Hadi Salim 
Cc: Cong Wang 
Cc: Jiri Pirko 
Reviewed-by: Jamal Hadi Salim 
Reviewed-by: Simon Horman 
Link: https://lore.kernel.org/r/20230620184425.1179809-1-edumazet@google.com
Signed-off-by: Paolo Abeni 
Signed-off-by: Sasha Levin

netfilter: nfnetlink_osf: fix module autoload

2023-06-28T08:18:40+00:00

[ Upstream commit 62f9a68a36d4441a6c412b81faed102594bc6670 ]

Move the alias from xt_osf to nfnetlink_osf.

Fixes: f9324952088f ("netfilter: nfnetlink_osf: extract nfnetlink_subsystem code from xt_osf.c")
Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Sasha Levin

netfilter: nf_tables: disallow element updates of bound anonymous sets

2023-06-28T08:18:40+00:00

[ Upstream commit c88c535b592d3baeee74009f3eceeeaf0fdd5e1b ]

Anonymous sets come with NFT_SET_CONSTANT from userspace. Although API
allows to create anonymous sets without NFT_SET_CONSTANT, it makes no
sense to allow to add and to delete elements for bound anonymous sets.

Fixes: 96518518cc41 ("netfilter: add nftables")
Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Sasha Levin

ipvs: align inner_mac_header for encapsulation

2023-06-28T08:18:39+00:00

[ Upstream commit d7fce52fdf96663ddc2eb21afecff3775588612a ]

When using encapsulation the original packet's headers are copied to the
inner headers. This preserves the space for an inner mac header, which
is not used by the inner payloads for the encapsulation types supported
by IPVS. If a packet is using GUE or GRE encapsulation and needs to be
segmented, flow can be passed to __skb_udp_tunnel_segment() which
calculates a negative tunnel header length. A negative tunnel header
length causes pskb_may_pull() to fail, dropping the packet.

This can be observed by attaching probes to ip_vs_in_hook(),
__dev_queue_xmit(), and __skb_udp_tunnel_segment():

    perf probe --add '__dev_queue_xmit skb->inner_mac_header \
    skb->inner_network_header skb->mac_header skb->network_header'
    perf probe --add '__skb_udp_tunnel_segment:7 tnl_hlen'
    perf probe -m ip_vs --add 'ip_vs_in_hook skb->inner_mac_header \
    skb->inner_network_header skb->mac_header skb->network_header'

These probes the headers and tunnel header length for packets which
traverse the IPVS encapsulation path. A TCP packet can be forced into
the segmentation path by being smaller than a calculated clamped MSS,
but larger than the advertised MSS.

    probe:ip_vs_in_hook: inner_mac_header=0x0 inner_network_header=0x0 mac_header=0x44 network_header=0x52
    probe:ip_vs_in_hook: inner_mac_header=0x44 inner_network_header=0x52 mac_header=0x44 network_header=0x32
    probe:dev_queue_xmit: inner_mac_header=0x44 inner_network_header=0x52 mac_header=0x44 network_header=0x32
    probe:__skb_udp_tunnel_segment_L7: tnl_hlen=-2

When using veth-based encapsulation, the interfaces are set to be
mac-less, which does not preserve space for an inner mac header. This
prevents this issue from occurring.

In our real-world testing of sending a 32KB file we observed operation
time increasing from ~75ms for veth-based encapsulation to over 1.5s
using IPVS encapsulation due to retries from dropped packets.

This changeset modifies the packet on the encapsulation path in
ip_vs_tunnel_xmit() and ip_vs_tunnel_xmit_v6() to remove the inner mac
header offset. This fixes UDP segmentation for both encapsulation types,
and corrects the inner headers for any IPIP flows that may use it.

Fixes: 84c0d5e96f3a ("ipvs: allow tunneling with gue encapsulation")
Signed-off-by: Terin Stock 
Acked-by: Julian Anastasov 
Acked-by: Simon Horman 
Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Sasha Levin

xfrm: Linearize the skb after offloading if needed.

2023-06-28T08:18:38+00:00

[ Upstream commit f015b900bc3285322029b4a7d132d6aeb0e51857 ]

With offloading enabled, esp_xmit() gets invoked very late, from within
validate_xmit_xfrm() which is after validate_xmit_skb() validates and
linearizes the skb if the underlying device does not support fragments.

esp_output_tail() may add a fragment to the skb while adding the auth
tag/ IV. Devices without the proper support will then send skb->data
points to with the correct length so the packet will have garbage at the
end. A pcap sniffer will claim that the proper data has been sent since
it parses the skb properly.

It is not affected with INET_ESP_OFFLOAD disabled.

Linearize the skb after offloading if the sending hardware requires it.
It was tested on v4, v6 has been adopted.

Fixes: 7785bba299a8d ("esp: Add a software GRO codepath")
Signed-off-by: Sebastian Andrzej Siewior 
Signed-off-by: Steffen Klassert 
Signed-off-by: Sasha Levin

neighbour: delete neigh_lookup_nodev as not used

2023-06-21T13:44:12+00:00

commit 76b9bf965c98c9b53ef7420b3b11438dbd764f92 upstream.

neigh_lookup_nodev isn't used in the kernel after removal
of DECnet. So let's remove it.

Fixes: 1202cdd66531 ("Remove DECnet support from kernel")
Signed-off-by: Leon Romanovsky 
Reviewed-by: Eric Dumazet 
Reviewed-by: Nikolay Aleksandrov 
Link: https://lore.kernel.org/r/eb5656200d7964b2d177a36b77efa3c597d6d72d.1678267343.git.leonro@nvidia.com
Signed-off-by: Jakub Kicinski 
Signed-off-by: Greg Kroah-Hartman

net: tipc: resize nlattr array to correct size

2023-06-21T13:44:12+00:00

[ Upstream commit 44194cb1b6045dea33ae9a0d54fb7e7cd93a2e09 ]

According to nla_parse_nested_deprecated(), the tb[] is supposed to the
destination array with maxtype+1 elements. In current
tipc_nl_media_get() and __tipc_nl_media_set(), a larger array is used
which is unnecessary. This patch resize them to a proper size.

Fixes: 1e55417d8fc6 ("tipc: add media set to new netlink api")
Fixes: 46f15c6794fb ("tipc: add media get/dump to new netlink api")
Signed-off-by: Lin Ma 
Reviewed-by: Florian Westphal 
Reviewed-by: Tung Nguyen 
Link: https://lore.kernel.org/r/20230614120604.1196377-1-linma@zju.edu.cn
Signed-off-by: Jakub Kicinski 
Signed-off-by: Sasha Levin

net/sched: cls_api: Fix lockup on flushing explicitly created chain

2023-06-21T13:44:12+00:00

[ Upstream commit c9a82bec02c339cdda99b37c5e62b3b71fc4209c ]

Mingshuai Ren reports:

When a new chain is added by using tc, one soft lockup alarm will be
 generated after delete the prio 0 filter of the chain. To reproduce
 the problem, perform the following steps:
(1) tc qdisc add dev eth0 root handle 1: htb default 1
(2) tc chain add dev eth0
(3) tc filter del dev eth0 chain 0 parent 1: prio 0
(4) tc filter add dev eth0 chain 0 parent 1:

Fix the issue by accounting for additional reference to chains that are
explicitly created by RTM_NEWCHAIN message as opposed to implicitly by
RTM_NEWTFILTER message.

Fixes: 726d061286ce ("net: sched: prevent insertion of new classifiers during chain flush")
Reported-by: Mingshuai Ren 
Closes: https://lore.kernel.org/lkml/87legswvi3.fsf@nvidia.com/T/
Signed-off-by: Vlad Buslov 
Link: https://lore.kernel.org/r/20230612093426.2867183-1-vladbu@nvidia.com
Signed-off-by: Jakub Kicinski 
Signed-off-by: Sasha Levin

sctp: fix an error code in sctp_sf_eat_auth()

2023-06-21T13:44:11+00:00

[ Upstream commit 75e6def3b26736e7ff80639810098c9074229737 ]

The sctp_sf_eat_auth() function is supposed to enum sctp_disposition
values and returning a kernel error code will cause issues in the
caller.  Change -ENOMEM to SCTP_DISPOSITION_NOMEM.

Fixes: 65b07e5d0d09 ("[SCTP]: API updates to suport SCTP-AUTH extensions.")
Signed-off-by: Dan Carpenter 
Acked-by: Xin Long 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

net/sched: cls_u32: Fix reference counter leak leading to overflow

2023-06-21T13:44:11+00:00

[ Upstream commit 04c55383fa5689357bcdd2c8036725a55ed632bc ]

In the event of a failure in tcf_change_indev(), u32_set_parms() will
immediately return without decrementing the recently incremented
reference counter.  If this happens enough times, the counter will
rollover and the reference freed, leading to a double free which can be
used to do 'bad things'.

In order to prevent this, move the point of possible failure above the
point where the reference counter is incremented.  Also save any
meaningful return values to be applied to the return data at the
appropriate point in time.

This issue was caught with KASAN.

Fixes: 705c7091262d ("net: sched: cls_u32: no need to call tcf_exts_change for newly allocated struct")
Suggested-by: Eric Dumazet 
Signed-off-by: Lee Jones 
Reviewed-by: Eric Dumazet 
Acked-by: Jamal Hadi Salim 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin