forked from Minki/linux
1ffbc7ea91
Reproduce:
modprobe sch_teql
tc qdisc add dev teql0 root teql0
This leads to (for instance in Centos 7 VM) OOPS:
[ 532.366633] BUG: unable to handle kernel NULL pointer dereference at 00000000000000a8
[ 532.366733] IP: [<ffffffffc06124a8>] teql_destroy+0x18/0x100 [sch_teql]
[ 532.366825] PGD 80000001376d5067 PUD 137e37067 PMD 0
[ 532.366906] Oops: 0000 [#1] SMP
[ 532.366987] Modules linked in: sch_teql ...
[ 532.367945] CPU: 1 PID: 3026 Comm: tc Kdump: loaded Tainted: G ------------ T 3.10.0-1062.7.1.el7.x86_64 #1
[ 532.368041] Hardware name: Virtuozzo KVM, BIOS 1.11.0-2.vz7.2 04/01/2014
[ 532.368125] task: ffff8b7d37d31070 ti: ffff8b7c9fdbc000 task.ti: ffff8b7c9fdbc000
[ 532.368224] RIP: 0010:[<ffffffffc06124a8>] [<ffffffffc06124a8>] teql_destroy+0x18/0x100 [sch_teql]
[ 532.368320] RSP: 0018:ffff8b7c9fdbf8e0 EFLAGS: 00010286
[ 532.368394] RAX: ffffffffc0612490 RBX: ffff8b7cb1565e00 RCX: ffff8b7d35ba2000
[ 532.368476] RDX: ffff8b7d35ba2000 RSI: 0000000000000000 RDI: ffff8b7cb1565e00
[ 532.368557] RBP: ffff8b7c9fdbf8f8 R08: ffff8b7d3fd1f140 R09: ffff8b7d3b001600
[ 532.368638] R10: ffff8b7d3b001600 R11: ffffffff84c7d65b R12: 00000000ffffffd8
[ 532.368719] R13: 0000000000008000 R14: ffff8b7d35ba2000 R15: ffff8b7c9fdbf9a8
[ 532.368800] FS: 00007f6a4e872740(0000) GS:ffff8b7d3fd00000(0000) knlGS:0000000000000000
[ 532.368885] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 532.368961] CR2: 00000000000000a8 CR3: 00000001396ee000 CR4: 00000000000206e0
[ 532.369046] Call Trace:
[ 532.369159] [<ffffffff84c8192e>] qdisc_create+0x36e/0x450
[ 532.369268] [<ffffffff846a9b49>] ? ns_capable+0x29/0x50
[ 532.369366] [<ffffffff849afde2>] ? nla_parse+0x32/0x120
[ 532.369442] [<ffffffff84c81b4c>] tc_modify_qdisc+0x13c/0x610
[ 532.371508] [<ffffffff84c693e7>] rtnetlink_rcv_msg+0xa7/0x260
[ 532.372668] [<ffffffff84907b65>] ? sock_has_perm+0x75/0x90
[ 532.373790] [<ffffffff84c69340>] ? rtnl_newlink+0x890/0x890
[ 532.374914] [<ffffffff84c8da7b>] netlink_rcv_skb+0xab/0xc0
[ 532.376055] [<ffffffff84c63708>] rtnetlink_rcv+0x28/0x30
[ 532.377204] [<ffffffff84c8d400>] netlink_unicast+0x170/0x210
[ 532.378333] [<ffffffff84c8d7a8>] netlink_sendmsg+0x308/0x420
[ 532.379465] [<ffffffff84c2f3a6>] sock_sendmsg+0xb6/0xf0
[ 532.380710] [<ffffffffc034a56e>] ? __xfs_filemap_fault+0x8e/0x1d0 [xfs]
[ 532.381868] [<ffffffffc034a75c>] ? xfs_filemap_fault+0x2c/0x30 [xfs]
[ 532.383037] [<ffffffff847ec23a>] ? __do_fault.isra.61+0x8a/0x100
[ 532.384144] [<ffffffff84c30269>] ___sys_sendmsg+0x3e9/0x400
[ 532.385268] [<ffffffff847f3fad>] ? handle_mm_fault+0x39d/0x9b0
[ 532.386387] [<ffffffff84d88678>] ? __do_page_fault+0x238/0x500
[ 532.387472] [<ffffffff84c31921>] __sys_sendmsg+0x51/0x90
[ 532.388560] [<ffffffff84c31972>] SyS_sendmsg+0x12/0x20
[ 532.389636] [<ffffffff84d8dede>] system_call_fastpath+0x25/0x2a
[ 532.390704] [<ffffffff84d8de21>] ? system_call_after_swapgs+0xae/0x146
[ 532.391753] Code: 00 00 00 00 00 00 5b 5d c3 66 2e 0f 1f 84 00 00 00 00 00 66 66 66 66 90 55 48 89 e5 41 55 41 54 53 48 8b b7 48 01 00 00 48 89 fb <48> 8b 8e a8 00 00 00 48 85 c9 74 43 48 89 ca eb 0f 0f 1f 80 00
[ 532.394036] RIP [<ffffffffc06124a8>] teql_destroy+0x18/0x100 [sch_teql]
[ 532.395127] RSP <ffff8b7c9fdbf8e0>
[ 532.396179] CR2: 00000000000000a8
Null pointer dereference happens on master->slaves dereference in
teql_destroy() as master is null-pointer.
When qdisc_create() calls teql_qdisc_init() it imediately fails after
check "if (m->dev == dev)" because both devices are teql0, and it does
not set qdisc_priv(sch)->m leaving it zero on error path, then
qdisc_create() imediately calls teql_destroy() which does not expect
zero master pointer and we get OOPS.
Fixes:
|
||
|---|---|---|
| .. | ||
| act_api.c | ||
| act_bpf.c | ||
| act_connmark.c | ||
| act_csum.c | ||
| act_ct.c | ||
| act_ctinfo.c | ||
| act_gact.c | ||
| act_gate.c | ||
| act_ife.c | ||
| act_ipt.c | ||
| act_meta_mark.c | ||
| act_meta_skbprio.c | ||
| act_meta_skbtcindex.c | ||
| act_mirred.c | ||
| act_mpls.c | ||
| act_nat.c | ||
| act_pedit.c | ||
| act_police.c | ||
| act_sample.c | ||
| act_simple.c | ||
| act_skbedit.c | ||
| act_skbmod.c | ||
| act_tunnel_key.c | ||
| act_vlan.c | ||
| cls_api.c | ||
| cls_basic.c | ||
| cls_bpf.c | ||
| cls_cgroup.c | ||
| cls_flow.c | ||
| cls_flower.c | ||
| cls_fw.c | ||
| cls_matchall.c | ||
| cls_route.c | ||
| cls_rsvp6.c | ||
| cls_rsvp.c | ||
| cls_rsvp.h | ||
| cls_tcindex.c | ||
| cls_u32.c | ||
| em_canid.c | ||
| em_cmp.c | ||
| em_ipset.c | ||
| em_ipt.c | ||
| em_meta.c | ||
| em_nbyte.c | ||
| em_text.c | ||
| em_u32.c | ||
| ematch.c | ||
| Kconfig | ||
| Makefile | ||
| sch_api.c | ||
| sch_atm.c | ||
| sch_blackhole.c | ||
| sch_cake.c | ||
| sch_cbq.c | ||
| sch_cbs.c | ||
| sch_choke.c | ||
| sch_codel.c | ||
| sch_drr.c | ||
| sch_dsmark.c | ||
| sch_etf.c | ||
| sch_ets.c | ||
| sch_fifo.c | ||
| sch_fq_codel.c | ||
| sch_fq_pie.c | ||
| sch_fq.c | ||
| sch_frag.c | ||
| sch_generic.c | ||
| sch_gred.c | ||
| sch_hfsc.c | ||
| sch_hhf.c | ||
| sch_htb.c | ||
| sch_ingress.c | ||
| sch_mq.c | ||
| sch_mqprio.c | ||
| sch_multiq.c | ||
| sch_netem.c | ||
| sch_pie.c | ||
| sch_plug.c | ||
| sch_prio.c | ||
| sch_qfq.c | ||
| sch_red.c | ||
| sch_sfb.c | ||
| sch_sfq.c | ||
| sch_skbprio.c | ||
| sch_taprio.c | ||
| sch_tbf.c | ||
| sch_teql.c | ||