On Mon, Feb 12, 2018 at 06:49:39PM +0100, Paolo Abeni wrote: > syzbot reported that xt_LED may try to use the ledinternal->timer > without previously initializing it: > > ------------[ cut here ]------------ > kernel BUG at kernel/time/timer.c:958! > invalid opcode: 0000 [#1] SMP KASAN > Dumping ftrace buffer: > (ftrace buffer empty) > Modules linked in: > CPU: 1 PID: 1826 Comm: kworker/1:2 Not tainted 4.15.0+ #306 > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS > Google 01/01/2011 > Workqueue: ipv6_addrconf addrconf_dad_work > RIP: 0010:__mod_timer kernel/time/timer.c:958 [inline] > RIP: 0010:mod_timer+0x7d6/0x13c0 kernel/time/timer.c:1102 > RSP: 0018:ffff8801d24fe9f8 EFLAGS: 00010293 > RAX: ffff8801d25246c0 RBX: ffff8801aec6cb50 RCX: ffffffff816052c6 > RDX: 0000000000000000 RSI: 00000000fffbd14b RDI: ffff8801aec6cb68 > RBP: ffff8801d24fec98 R08: 0000000000000000 R09: 1ffff1003a49fd6c > R10: ffff8801d24feb28 R11: 0000000000000005 R12: dffffc0000000000 > R13: ffff8801d24fec70 R14: 00000000fffbd14b R15: ffff8801af608f90 > FS: 0000000000000000(0000) GS:ffff8801db500000(0000) knlGS:0000000000000000 > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > CR2: 00000000206d6fd0 CR3: 0000000006a22001 CR4: 00000000001606e0 > DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 > Call Trace: > led_tg+0x1db/0x2e0 net/netfilter/xt_LED.c:75 > ip6t_do_table+0xc2a/0x1a30 net/ipv6/netfilter/ip6_tables.c:365 > ip6table_raw_hook+0x65/0x80 net/ipv6/netfilter/ip6table_raw.c:42 > nf_hook_entry_hookfn include/linux/netfilter.h:120 [inline] > nf_hook_slow+0xba/0x1a0 net/netfilter/core.c:483 > nf_hook.constprop.27+0x3f6/0x830 include/linux/netfilter.h:243 > NF_HOOK include/linux/netfilter.h:286 [inline] > ndisc_send_skb+0xa51/0x1370 net/ipv6/ndisc.c:491 > ndisc_send_ns+0x38a/0x870 net/ipv6/ndisc.c:633 > addrconf_dad_work+0xb9e/0x1320 net/ipv6/addrconf.c:4008 > process_one_work+0xbbf/0x1af0 kernel/workqueue.c:2113 > worker_thread+0x223/0x1990 kernel/workqueue.c:2247 > kthread+0x33c/0x400 kernel/kthread.c:238 > ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:429 > Code: 85 2a 0b 00 00 4d 8b 3c 24 4d 85 ff 75 9f 4c 8b bd 60 fd ff ff e8 bb > 57 10 00 65 ff 0d 94 9a a1 7e e9 d9 fc ff ff e8 aa 57 10 00 <0f> 0b e8 a3 > 57 10 00 e9 14 fb ff ff e8 99 57 10 00 4c 89 bd 70 > RIP: __mod_timer kernel/time/timer.c:958 [inline] RSP: ffff8801d24fe9f8 > RIP: mod_timer+0x7d6/0x13c0 kernel/time/timer.c:1102 RSP: ffff8801d24fe9f8 > ---[ end trace f661ab06f5dd8b3d ]--- > > The ledinternal struct can be shared between several different > xt_LED targets, but the related timer is currently initialized only > if the first target requires it. Fix it by unconditionally > initializing the timer struct. Applied, thanks. -- To unsubscribe from this list: send the line "unsubscribe netfilter-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
