Hangbin Liu 51f6a134cf net_sched: fix NULL pointer dereference when delete tcindex filter ... [ Upstream commit 2df8bee5654bb2b7312662ca6810d4dc16b0b67f ] Li Shuang reported the following crash: [ 71.267724] BUG: unable to handle kernel NULL pointer dereference at 0000000000000004 [ 71.276456] PGD 800000085d9bd067 P4D 800000085d9bd067 PUD 859a0b067 PMD 0 [ 71.284127] Oops: 0000 [#1] SMP PTI [ 71.288015] CPU: 12 PID: 2386 Comm: tc Not tainted 4.18.0-rc8.latest+ #131 [ 71.295686] Hardware name: Dell Inc. PowerEdge R730/0WCJNT, BIOS 2.1.5 04/11/2016 [ 71.304037] RIP: 0010:tcindex_delete+0x72/0x280 [cls_tcindex] [ 71.310446] Code: 00 31 f6 48 87 75 20 48 85 f6 74 11 48 8b 47 18 48 8b 40 08 48 8b 40 50 e8 fb a6 f8 fc 48 85 db 0f 84 dc 00 00 00 48 8b 73 18 <8b> 56 04 48 8d 7e 04 85 d2 0f 84 7b 01 00 [ 71.331517] RSP: 0018:ffffb45207b3f898 EFLAGS: 00010282 [ 71.337345] RAX: ffff8ad3d72d6360 RBX: ffff8acc84393680 RCX: 000000000000002e [ 71.345306] RDX: ffff8ad3d72c8570 RSI: 0000000000000000 RDI: ffff8ad847a45800 [ 71.353277] RBP: ffff8acc84393688 R08: ffff8ad3d72c8400 R09: 0000000000000000 [ 71.361238] R10: ffff8ad3de786e00 R11: 0000000000000000 R12: ffffb45207b3f8c7 [ 71.369199] R13: ffff8ad3d93bd2a0 R14: 000000000000002e R15: ffff8ad3d72c9600 [ 71.377161] FS: 00007f9d3ec3e740(0000) GS:ffff8ad3df980000(0000) knlGS:0000000000000000 [ 71.386188] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 71.392597] CR2: 0000000000000004 CR3: 0000000852f06003 CR4: 00000000001606e0 [ 71.400558] Call Trace: [ 71.403299] tcindex_destroy_element+0x25/0x40 [cls_tcindex] [ 71.409611] tcindex_walk+0xbb/0x110 [cls_tcindex] [ 71.414953] tcindex_destroy+0x44/0x90 [cls_tcindex] [ 71.420492] ? tcindex_delete+0x280/0x280 [cls_tcindex] [ 71.426323] tcf_proto_destroy+0x16/0x40 [ 71.430696] tcf_chain_flush+0x51/0x70 [ 71.434876] tcf_block_put_ext.part.30+0x8f/0x1b0 [ 71.440122] tcf_block_put+0x4d/0x70 [ 71.444108] cbq_destroy+0x4d/0xd0 [sch_cbq] [ 71.448869] qdisc_destroy+0x62/0x130 [ 71.452951] dsmark_destroy+0x2a/0x70 [sch_dsmark] [ 71.458300] qdisc_destroy+0x62/0x130 [ 71.462373] qdisc_graft+0x3ba/0x470 [ 71.466359] tc_get_qdisc+0x2a6/0x2c0 [ 71.470443] ? cred_has_capability+0x7d/0x130 [ 71.475307] rtnetlink_rcv_msg+0x263/0x2d0 [ 71.479875] ? rtnl_calcit.isra.30+0x110/0x110 [ 71.484832] netlink_rcv_skb+0x4d/0x130 [ 71.489109] netlink_unicast+0x1a3/0x250 [ 71.493482] netlink_sendmsg+0x2ae/0x3a0 [ 71.497859] sock_sendmsg+0x36/0x40 [ 71.501748] ___sys_sendmsg+0x26f/0x2d0 [ 71.506029] ? handle_pte_fault+0x586/0xdf0 [ 71.510694] ? __handle_mm_fault+0x389/0x500 [ 71.515457] ? __sys_sendmsg+0x5e/0xa0 [ 71.519636] __sys_sendmsg+0x5e/0xa0 [ 71.523626] do_syscall_64+0x5b/0x180 [ 71.527711] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 71.533345] RIP: 0033:0x7f9d3e257f10 [ 71.537331] Code: c3 48 8b 05 82 6f 2c 00 f7 db 64 89 18 48 83 cb ff eb dd 0f 1f 80 00 00 00 00 83 3d 8d d0 2c 00 00 75 10 b8 2e 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 [ 71.558401] RSP: 002b:00007fff6f893398 EFLAGS: 00000246 ORIG_RAX: 000000000000002e [ 71.566848] RAX: ffffffffffffffda RBX: 000000005b71274d RCX: 00007f9d3e257f10 [ 71.574810] RDX: 0000000000000000 RSI: 00007fff6f8933e0 RDI: 0000000000000003 [ 71.582770] RBP: 00007fff6f8933e0 R08: 000000000000ffff R09: 0000000000000003 [ 71.590729] R10: 00007fff6f892e20 R11: 0000000000000246 R12: 0000000000000000 [ 71.598689] R13: 0000000000662ee0 R14: 0000000000000000 R15: 0000000000000000 [ 71.606651] Modules linked in: sch_cbq cls_tcindex sch_dsmark xt_CHECKSUM iptable_mangle ipt_MASQUERADE iptable_nat nf_nat_ipv4 nf_nat nf_conntrack_ipv4 nf_defrag_ipv4 xt_conntrack nf_coni [ 71.685425] libahci i2c_algo_bit i2c_core i40e libata dca mdio megaraid_sas dm_mirror dm_region_hash dm_log dm_mod [ 71.697075] CR2: 0000000000000004 [ 71.700792] ---[ end trace f604eb1acacd978b ]--- Reproducer: tc qdisc add dev lo handle 1:0 root dsmark indices 64 set_tc_index tc filter add dev lo parent 1:0 protocol ip prio 1 tcindex mask 0xfc shift 2 tc qdisc add dev lo parent 1:0 handle 2:0 cbq bandwidth 10Mbit cell 8 avpkt 1000 mpu 64 tc class add dev lo parent 2:0 classid 2:1 cbq bandwidth 10Mbit rate 1500Kbit avpkt 1000 prio 1 bounded isolated allot 1514 weight 1 maxburst 10 tc filter add dev lo parent 2:0 protocol ip prio 1 handle 0x2e tcindex classid 2:1 pass_on tc qdisc add dev lo parent 2:1 pfifo limit 5 tc qdisc del dev lo root This is because in tcindex_set_parms, when there is no old_r, we set new exts to cr.exts. And we didn't set it to filter when r == &new_filter_result. Then in tcindex_delete() -> tcf_exts_get_net(), we will get NULL pointer dereference as we didn't init exts. Fix it by moving tcf_exts_change() after "if (old_r && old_r != r)" check. Then we don't need "cr" as there is no errout after that. Fixes: bf63ac73b3 ("net_sched: fix an oops in tcindex filter") Reported-by: Li Shuang <shuali@redhat.com> Signed-off-by: Hangbin Liu <liuhangbin@gmail.com> Acked-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2018-08-22 07:48:35 +02:00
..
6lowpan	6lowpan: put mcast compression in an own function	2015-10-21 00:49:25 +02:00
9p	net/9p: Switch to wait_event_killable()	2017-11-30 08:37:25 +00:00
802
8021q	vlan: also check phy_driver ts_info for vlan's real device	2018-04-13 19:50:25 +02:00
appletalk
atm	net: atm: Fix potential Spectre v1	2018-05-16 10:06:51 +02:00
ax25	ax25: Fix segfault after sock connection timeout	2017-02-04 09:45:09 +01:00
batman-adv	batman-adv: fix packet loss for broadcasted DHCP packets to a server	2018-05-30 07:49:06 +02:00
bluetooth	Bluetooth: hidp: buffer overflow in hidp_process_report	2018-08-17 20:56:45 +02:00
bridge	netfilter: ebtables: reject non-bridge targets	2018-07-22 14:25:54 +02:00
caif	net: caif: Fix a sleep-in-atomic bug in cfpkt_create_pfx	2017-07-05 14:37:14 +02:00
can	can: af_can: canfd_rcv(): replace WARN_ONCE by pr_warn_once	2018-01-31 12:06:08 +01:00
ceph	libceph: validate con->state at the top of try_write()	2018-05-02 07:53:42 -07:00
core	rtnetlink: add rtnl_link_state check in rtnl_configure_link	2018-07-28 07:45:02 +02:00
dcb	net/dcb: make dcbnl.c explicitly non-modular	2015-10-09 07:52:27 -07:00
dccp	dccp: fix undefined behavior with 'cwnd' shift in ccid2_cwnd_restart()	2018-08-22 07:48:35 +02:00
decnet	dn_getsockoptdecnet: move nf_{get/set}sockopt outside sock lock	2018-02-25 11:03:38 +01:00
dns_resolver	KEYS: DNS: fix parsing multiple options	2018-07-22 14:25:54 +02:00
dsa	net: dsa: Do not suspend/resume closed slave_dev	2018-08-06 16:24:41 +02:00
ethernet	net: introduce device min_header_len	2017-02-18 16:39:27 +01:00
hsr	net/hsr: fix a warning message	2015-11-23 14:56:15 -05:00
ieee802154	net: ieee802154: fix net_device reference release too early	2018-04-13 19:50:10 +02:00
ipv4	tcp: Fix missing range_truesize enlargement in the backport	2018-08-17 20:56:44 +02:00
ipv6	ipv4+ipv6: Make INET*_ESP select CRYPTO_ECHAINIV	2018-08-15 17:42:05 +02:00
ipx	ipx: call ipxitf_put() in ioctl error path	2017-05-25 14:30:13 +02:00
irda	irda: do not leak initialized list.dev to userspace	2017-08-30 10:19:21 +02:00
iucv	net/iucv: Free memory obtained by kzalloc	2018-03-31 18:12:33 +02:00
key	af_key: Always verify length of provided sadb_key	2018-06-16 09:54:25 +02:00
l2tp	l2tp: use sk_dst_check() to avoid race on sk->sk_dst_cache	2018-08-22 07:48:35 +02:00
l3mdev	net: Add netif_is_l3_slave	2015-10-07 04:27:43 -07:00
lapb
llc	llc: use refcount_inc_not_zero() for llc_sap_find()	2018-08-22 07:48:35 +02:00
mac80211	mac80211: Add RX flag to indicate ICV stripped	2018-05-16 10:06:46 +02:00
mac802154	mac802154: llsec: use kzfree	2015-10-21 00:49:24 +02:00
mpls	mpls, nospec: Sanitize array index in mpls_label_ok()	2018-03-11 16:19:47 +01:00
netfilter	netfilter: nf_queue: augment nfqa_cfg_policy	2018-07-17 11:31:46 +02:00
netlabel	netlabel: If PF_INET6, check sk_buff ip header version	2018-05-30 07:49:17 +02:00
netlink	netlink: Don't shift on 64 for ngroups	2018-08-09 12:19:28 +02:00
netrom
nfc	net/nfc: Avoid stalls when nfc_alloc_send_skb() returned NULL.	2018-07-22 14:25:54 +02:00
openvswitch	openvswitch: Don't swap table in nlattr_set() after OVS_ATTR_NESTED is found	2018-05-26 08:48:47 +02:00
packet	packet: fix reserve calculation	2018-06-13 16:15:28 +02:00
phonet	phonet: properly unshare skbs in phonet_rcv()	2016-01-31 11:29:00 -08:00
rds	rds: avoid unenecessary cong_update in loop transport	2018-07-22 14:25:54 +02:00
rfkill	rfkill: gpio: fix memory leak in probe error path	2018-05-16 10:06:51 +02:00
rose
rxrpc	rxrpc: check return value of skb_to_sgvec always	2018-04-13 19:50:23 +02:00
sched	net_sched: fix NULL pointer dereference when delete tcindex filter	2018-08-22 07:48:35 +02:00
sctp	sctp: delay the authentication for the duplicated cookie-echo chunk	2018-05-26 08:48:49 +02:00
sunrpc	rpc_pipefs: fix double-dput()	2018-04-24 09:32:11 +02:00
switchdev	switchdev: pass pointer to fib_info instead of copy	2016-06-24 10:18:16 -07:00
tipc	tipc: add policy for TIPC_NLA_NET_ADDR	2018-04-29 07:50:06 +02:00
unix	net/unix: don't show information about sockets from other namespaces	2017-11-18 11:11:06 +01:00
vmw_vsock	vsock: split dwork to avoid reinitializations	2018-08-22 07:48:35 +02:00
wimax
wireless	cfg80211: limit wiphy names to 128 bytes	2018-05-26 08:49:00 +02:00
x25	net: x25: fix one potential use-after-free issue	2018-04-13 19:50:07 +02:00
xfrm	xfrm: skip policies marked as dead while rehashing	2018-07-03 11:21:32 +02:00
compat.c	net: support compat 64-bit time in {s,g}etsockopt	2018-05-26 08:48:47 +02:00
Kconfig	Make DST_CACHE a silent config option	2018-02-25 11:03:37 +01:00
Makefile	net: Introduce L3 Master device abstraction	2015-09-29 20:40:32 -07:00
socket.c	net: socket: fix potential spectre v1 gadget in socketcall	2018-08-06 16:24:42 +02:00
sysctl_net.c	net: Use ns_capable_noaudit() when determining net sysctl permissions	2016-09-15 08:27:50 +02:00