Yan Zhai 876e8ca836 net: fix NULL pointer in skb_segment_list ... Commit 3a1296a38d ("net: Support GRO/GSO fraglist chaining.") introduced UDP listifyed GRO. The segmentation relies on frag_list being untouched when passing through the network stack. This assumption can be broken sometimes, where frag_list itself gets pulled into linear area, leaving frag_list being NULL. When this happens it can trigger following NULL pointer dereference, and panic the kernel. Reverse the test condition should fix it. [19185.577801][ C1] BUG: kernel NULL pointer dereference, address: ... [19185.663775][ C1] RIP: 0010:skb_segment_list+0x1cc/0x390 ... [19185.834644][ C1] Call Trace: [19185.841730][ C1] <TASK> [19185.848563][ C1] __udp_gso_segment+0x33e/0x510 [19185.857370][ C1] inet_gso_segment+0x15b/0x3e0 [19185.866059][ C1] skb_mac_gso_segment+0x97/0x110 [19185.874939][ C1] __skb_gso_segment+0xb2/0x160 [19185.883646][ C1] udp_queue_rcv_skb+0xc3/0x1d0 [19185.892319][ C1] udp_unicast_rcv_skb+0x75/0x90 [19185.900979][ C1] ip_protocol_deliver_rcu+0xd2/0x200 [19185.910003][ C1] ip_local_deliver_finish+0x44/0x60 [19185.918757][ C1] __netif_receive_skb_one_core+0x8b/0xa0 [19185.927834][ C1] process_backlog+0x88/0x130 [19185.935840][ C1] __napi_poll+0x27/0x150 [19185.943447][ C1] net_rx_action+0x27e/0x5f0 [19185.951331][ C1] ? mlx5_cq_tasklet_cb+0x70/0x160 [mlx5_core] [19185.960848][ C1] __do_softirq+0xbc/0x25d [19185.968607][ C1] irq_exit_rcu+0x83/0xb0 [19185.976247][ C1] common_interrupt+0x43/0xa0 [19185.984235][ C1] asm_common_interrupt+0x22/0x40 ... [19186.094106][ C1] </TASK> Fixes: 3a1296a38d ("net: Support GRO/GSO fraglist chaining.") Suggested-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Willem de Bruijn <willemb@google.com> Signed-off-by: Yan Zhai <yan@cloudflare.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/r/Y9gt5EUizK1UImEP@debian Signed-off-by: Jakub Kicinski <kuba@kernel.org>		2023-01-31 21:07:04 -08:00
..
bpf_sk_storage.c	bpf: Fix a compilation failure with clang lto build	2022-11-30 17:13:25 -08:00
datagram.c	tcp: TX zerocopy should not sense pfmemalloc status	2022-09-02 12:29:02 +01:00
dev.c	net: add netdev_sw_irq_coalesce_default_on()	2022-12-03 21:48:36 +00:00
dev.h	net: add new helper unregister_netdevice_many_notify	2022-10-31 18:10:21 -07:00
dev_addr_lists.c
dev_addr_lists_test.c	kunit: Use KUNIT_EXPECT_MEMEQ macro	2022-10-27 02:40:14 -06:00
dev_ioctl.c	net: dev: Convert sa_data to flexible array in struct sockaddr	2022-10-25 11:44:20 -07:00
devlink.c	devlink: protect devlink dump by the instance lock	2022-12-16 21:16:28 -08:00
drop_monitor.c	genetlink: introduce split op representation	2022-11-07 12:30:16 +00:00
dst.c	Networking changes for 6.2.	2022-12-13 15:47:48 -08:00
dst_cache.c
failover.c	net: failover: use IFF_NO_ADDRCONF flag to prevent ipv6 addrconf	2022-12-12 15:18:25 -08:00
fib_notifier.c
fib_rules.c
filter.c	bpf: pull before calling skb_postpull_rcsum()	2022-12-20 15:58:35 -08:00
flow_dissector.c	Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net	2022-11-29 13:04:52 -08:00
flow_offload.c	net: flow_offload: add support for ARP frame matching	2022-11-14 11:24:16 +00:00
gen_estimator.c	treewide: Convert del_timer*() to timer_shutdown*()	2022-12-25 13:38:09 -08:00
gen_stats.c	net: Remove the obsolte u64_stats_fetch_*_irq() users (net).	2022-10-28 20:13:54 -07:00
gro.c	skb: Do mix page pool and page referenced frags in GRO	2023-01-27 23:21:27 -08:00
gro_cells.c	net: drop the weight argument from netif_napi_add	2022-09-28 18:57:14 -07:00
hwbm.c
link_watch.c	net: linkwatch: only report IF_OPER_LOWERLAYERDOWN if iflink is actually down	2022-11-16 09:45:00 +00:00
lwt_bpf.c
lwtunnel.c	xfrm: lwtunnel: squelch kernel warning in case XFRM encap type is not available	2022-10-12 10:45:51 +02:00
Makefile	net: skb: export skb drop reaons to user by TRACE_DEFINE_ENUM	2022-09-07 15:28:08 +01:00
neighbour.c	Random number generator updates for Linux 6.2-rc1.	2022-12-12 16:22:22 -08:00
net-procfs.c
net-sysfs.c	Driver Core changes for 6.2-rc1	2022-12-16 03:54:54 -08:00
net-sysfs.h
net-traces.c
net_namespace.c	net: fix UaF in netns ops registration error path	2023-01-20 18:51:18 -08:00
netclassid_cgroup.c	core: Variable type completion	2022-08-31 09:40:34 +01:00
netevent.c
netpoll.c	net: move from strlcpy with unused retval to strscpy	2022-08-22 18:06:18 -07:00
netprio_cgroup.c
of_net.c	of: net: export of_get_mac_address_nvmem()	2022-11-29 10:45:53 +01:00
page_pool.c
pktgen.c	treewide: use get_random_u32_inclusive() when possible	2022-11-18 02:18:02 +01:00
ptp_classifier.c
request_sock.c
rtnetlink.c	net: expose devlink port over rtnetlink	2022-11-03 20:48:37 -07:00
scm.c
secure_seq.c
selftests.c
skbuff.c	net: fix NULL pointer in skb_segment_list	2023-01-31 21:07:04 -08:00
skmsg.c	bpf, sockmap: Fix missing BPF_F_INGRESS flag when using apply_bytes	2022-12-01 01:07:32 +01:00
sock.c	net: Introduce sk_use_task_frag in struct sock.	2022-12-19 17:28:49 -08:00
sock_destructor.h
sock_diag.c	net: fix __sock_gen_cookie()	2022-11-21 20:36:30 -08:00
sock_map.c	bpf, sockmap: Don't let sock_map_{close,destroy,unhash} call itself	2023-01-24 21:32:55 -08:00
sock_reuseport.c	soreuseport: Fix socket selection for SO_INCOMING_CPU.	2022-10-25 11:35:16 +02:00
stream.c	net: stream: purge sk_error_queue in sk_stream_kill_queues()	2022-12-19 12:33:16 +00:00
sysctl_net_core.c	net: sysctl: remove unused variable long_max	2022-09-07 15:31:19 +01:00
timestamping.c
tso.c	net: tso: inline tso_count_descs()	2022-12-12 15:04:39 -08:00
utils.c	net: core: inet[46]_pton strlen len types	2022-11-01 21:14:39 -07:00
xdp.c	xdp: improve page_pool xdp_return performance	2022-09-26 11:28:19 -07:00