syzbot


KASAN: global-out-of-bounds Write in record_print_text

Status: upstream: reported C repro on 2021/01/25 21:14
Subsystems: kernel (incorrect?)
Reported-by: syzbot+db1faa35484efb6a54ea@syzkaller.appspotmail.com
First crash: 797d, last: 792d

Cause bisection: introduced by (bisect log) :
commit f0e386ee0c0b71ea6f7238506a4d0965a2dbef11
Author: John Ogness <john.ogness@linutronix.de>
Date: Thu Jan 14 17:04:12 2021 +0000

  printk: fix buffer overflow potential for print_text()

Crash: WARNING: bad unlock balance in ip6_output (log)
Repro: C syz .config

Fix bisection: fixed by (bisect log) [no-op commit]:
commit 38d26b244367e84ed657ac4f5093ae9e71c8a7a2
Author: Michael Walle <michael@walle.cc>
Date: Mon Dec 28 13:00:31 2020 +0000

  enetc: drop unneeded indirection

similar bugs (1):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KASAN: slab-out-of-bounds Write in record_print_text fs C done unreliable 17 791d 794d 21/24 fixed on 2021/03/10 01:48
Last patch testing requests:
Created Duration User Patch Repo Result
2023/01/06 06:31 20m retest repro linux-next error
2022/09/27 22:30 17m retest repro linux-next error
2022/09/25 00:30 16m retest repro upstream OK log
2022/09/24 21:30 16m retest repro upstream OK log

Sample crash report:
netdevsim netdevsim0 netdevsim3 (unregistering): unset [1, 0] type 2 family 0 port 6081 - 0
==================================================================
BUG: KASAN: global-out-of-bounds in record_print_text+0x33f/0x380 kernel/printk/printk.c:1401
Write of size 1 at addr ffffffff8f09f144 by task kworker/u4:0/9

CPU: 1 PID: 9 Comm: kworker/u4:0 Not tainted 5.11.0-rc4-next-20210121-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: netns cleanup_net
Call Trace:
 __dump_stack lib/dump_stack.c:79 [inline]
 dump_stack+0x107/0x163 lib/dump_stack.c:120
 print_address_description.constprop.0.cold+0x5/0x2f8 mm/kasan/report.c:230
 __kasan_report mm/kasan/report.c:397 [inline]
 kasan_report.cold+0x79/0xd5 mm/kasan/report.c:414
 record_print_text+0x33f/0x380 kernel/printk/printk.c:1401
 console_unlock+0x318/0xbb0 kernel/printk/printk.c:2555
 vprintk_emit+0x189/0x490 kernel/printk/printk.c:2092
 dev_vprintk_emit+0x36e/0x3b2 drivers/base/core.c:4358
 dev_printk_emit+0xba/0xf1 drivers/base/core.c:4369
 __netdev_printk+0x1c6/0x27a net/core/dev.c:11073
 netdev_info+0xd7/0x109 net/core/dev.c:11128
 nsim_udp_tunnel_unset_port.cold+0x95/0xb8 drivers/net/netdevsim/udp_tunnels.c:64
 udp_tunnel_nic_device_sync_one net/ipv4/udp_tunnel_nic.c:225 [inline]
 udp_tunnel_nic_device_sync_by_port net/ipv4/udp_tunnel_nic.c:246 [inline]
 __udp_tunnel_nic_device_sync.part.0+0xa4c/0xcb0 net/ipv4/udp_tunnel_nic.c:289
 __udp_tunnel_nic_device_sync net/ipv4/udp_tunnel_nic.c:283 [inline]
 udp_tunnel_nic_flush+0x2b4/0x5e0 net/ipv4/udp_tunnel_nic.c:668
 udp_tunnel_nic_unregister net/ipv4/udp_tunnel_nic.c:869 [inline]
 udp_tunnel_nic_netdevice_event+0x65c/0x19a0 net/ipv4/udp_tunnel_nic.c:909
 notifier_call_chain+0xb5/0x200 kernel/notifier.c:83
 call_netdevice_notifiers_info+0xb5/0x130 net/core/dev.c:2040
 call_netdevice_notifiers_extack net/core/dev.c:2052 [inline]
 call_netdevice_notifiers net/core/dev.c:2066 [inline]
 rollback_registered_many+0x92e/0x14c0 net/core/dev.c:9513
 rollback_registered net/core/dev.c:9558 [inline]
 unregister_netdevice_queue+0x2dd/0x570 net/core/dev.c:10734
 unregister_netdevice include/linux/netdevice.h:2853 [inline]
 nsim_destroy+0x35/0x70 drivers/net/netdevsim/netdev.c:338
 __nsim_dev_port_del+0x144/0x1e0 drivers/net/netdevsim/dev.c:967
 nsim_dev_port_del_all drivers/net/netdevsim/dev.c:980 [inline]
 nsim_dev_reload_destroy+0xff/0x1e0 drivers/net/netdevsim/dev.c:1158
 nsim_dev_reload_down+0x6e/0xd0 drivers/net/netdevsim/dev.c:725
 devlink_reload+0x15a/0x5e0 net/core/devlink.c:3191
 devlink_pernet_pre_exit+0x154/0x220 net/core/devlink.c:10329
 ops_pre_exit_list net/core/net_namespace.c:177 [inline]
 cleanup_net+0x451/0xb10 net/core/net_namespace.c:592
 process_one_work+0x98d/0x15f0 kernel/workqueue.c:2275
 worker_thread+0x64c/0x1120 kernel/workqueue.c:2421
 kthread+0x3b1/0x4a0 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296

The buggy address belongs to the variable:
 dmesg_restrict+0x24/0x40

Memory state around the buggy address:
 ffffffff8f09f000: f9 f9 f9 f9 01 f9 f9 f9 f9 f9 f9 f9 00 f9 f9 f9
 ffffffff8f09f080: f9 f9 f9 f9 01 f9 f9 f9 f9 f9 f9 f9 00 f9 f9 f9
>ffffffff8f09f100: f9 f9 f9 f9 04 f9 f9 f9 f9 f9 f9 f9 00 00 00 00
                                           ^
 ffffffff8f09f180: 00 00 00 00 00 00 f9 f9 f9 f9 f9 f9 00 00 00 00
 ffffffff8f09f200: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================

Crashes (45):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets Title
ci-upstream-linux-next-kasan-gce-root 2021/01/21 21:25 linux-next bc085f8fc88f d4f4eca5 .config console log report syz C KASAN: global-out-of-bounds Write in record_print_text
ci-upstream-kasan-gce-selinux-root 2021/01/23 04:57 upstream 83d09ad4b950 4080af96 .config console log report syz C KASAN: global-out-of-bounds Write in record_print_text
ci-upstream-kasan-gce-selinux-root 2021/01/23 04:25 upstream 83d09ad4b950 4080af96 .config console log report syz C KASAN: global-out-of-bounds Write in record_print_text
ci-upstream-kasan-gce-smack-root 2021/01/25 12:21 upstream 6ee1d745b7c9 52e37319 .config console log report info KASAN: global-out-of-bounds Write in record_print_text
ci-upstream-kasan-gce-smack-root 2021/01/25 04:10 upstream e68061375f79 52e37319 .config console log report info KASAN: global-out-of-bounds Write in record_print_text
ci-upstream-kasan-gce-smack-root 2021/01/25 04:10 upstream e68061375f79 52e37319 .config console log report info KASAN: global-out-of-bounds Write in record_print_text
ci-upstream-kasan-gce-root 2021/01/24 17:32 upstream e1ae4b0be158 52e37319 .config console log report info KASAN: global-out-of-bounds Write in record_print_text
ci-upstream-kasan-gce-root 2021/01/24 17:32 upstream e1ae4b0be158 52e37319 .config console log report info KASAN: global-out-of-bounds Write in record_print_text
ci-upstream-kasan-gce-smack-root 2021/01/24 16:58 upstream e1ae4b0be158 52e37319 .config console log report info KASAN: global-out-of-bounds Write in record_print_text
ci-upstream-kasan-gce-smack-root 2021/01/24 16:58 upstream e1ae4b0be158 52e37319 .config console log report info KASAN: global-out-of-bounds Write in record_print_text
ci-upstream-kasan-gce-selinux-root 2021/01/24 16:53 upstream e1ae4b0be158 52e37319 .config console log report info KASAN: global-out-of-bounds Write in record_print_text
ci-upstream-kasan-gce-selinux-root 2021/01/24 16:52 upstream e1ae4b0be158 52e37319 .config console log report info KASAN: global-out-of-bounds Write in record_print_text
ci-upstream-kasan-gce-root 2021/01/24 10:16 upstream e1ae4b0be158 52e37319 .config console log report info KASAN: global-out-of-bounds Write in record_print_text
ci-upstream-kasan-gce-smack-root 2021/01/24 01:44 upstream e1ae4b0be158 52e37319 .config console log report info KASAN: global-out-of-bounds Write in record_print_text
ci-upstream-kasan-gce-root 2021/01/23 21:14 upstream fe75a21824e7 52e37319 .config console log report info KASAN: global-out-of-bounds Write in record_print_text
ci-upstream-kasan-gce-selinux-root 2021/01/23 21:14 upstream fe75a21824e7 52e37319 .config console log report info KASAN: global-out-of-bounds Write in record_print_text
ci-upstream-kasan-gce-root 2021/01/23 21:14 upstream fe75a21824e7 52e37319 .config console log report info KASAN: global-out-of-bounds Write in record_print_text
ci-upstream-kasan-gce-selinux-root 2021/01/23 21:08 upstream fe75a21824e7 52e37319 .config console log report info KASAN: global-out-of-bounds Write in record_print_text
ci-upstream-kasan-gce-smack-root 2021/01/23 21:07 upstream fe75a21824e7 52e37319 .config console log report info KASAN: global-out-of-bounds Write in record_print_text
ci-upstream-kasan-gce-smack-root 2021/01/23 21:07 upstream fe75a21824e7 52e37319 .config console log report info KASAN: global-out-of-bounds Write in record_print_text
ci-upstream-kasan-gce-selinux-root 2021/01/23 03:10 upstream 83d09ad4b950 4080af96 .config console log report info KASAN: global-out-of-bounds Write in record_print_text
ci-upstream-kasan-gce-smack-root 2021/01/23 00:41 upstream 83d09ad4b950 4080af96 .config console log report info KASAN: global-out-of-bounds Write in record_print_text
ci-upstream-kasan-gce-selinux-root 2021/01/23 00:38 upstream 83d09ad4b950 4080af96 .config console log report info KASAN: global-out-of-bounds Write in record_print_text
ci-upstream-kasan-gce-root 2021/01/23 00:34 upstream 83d09ad4b950 4080af96 .config console log report info KASAN: global-out-of-bounds Write in record_print_text
ci-upstream-kasan-gce-smack-root 2021/01/23 00:34 upstream 83d09ad4b950 4080af96 .config console log report info KASAN: global-out-of-bounds Write in record_print_text
ci-upstream-kasan-gce-root 2021/01/23 00:33 upstream 83d09ad4b950 4080af96 .config console log report info KASAN: global-out-of-bounds Write in record_print_text
ci-upstream-kasan-gce-smack-root 2021/01/23 00:31 upstream 83d09ad4b950 4080af96 .config console log report info KASAN: global-out-of-bounds Write in record_print_text
ci-upstream-kasan-gce-smack-root 2021/01/22 10:08 upstream 9f29bd8b2e71 d4f4eca5 .config console log report info KASAN: global-out-of-bounds Write in record_print_text
ci-upstream-kasan-gce-selinux-root 2021/01/22 06:26 upstream 9f29bd8b2e71 d4f4eca5 .config console log report info KASAN: global-out-of-bounds Write in record_print_text
ci-upstream-kasan-gce-smack-root 2021/01/22 06:24 upstream 9f29bd8b2e71 d4f4eca5 .config console log report info KASAN: global-out-of-bounds Write in record_print_text
ci-upstream-kasan-gce-root 2021/01/22 05:13 upstream 9f29bd8b2e71 d4f4eca5 .config console log report info KASAN: global-out-of-bounds Write in record_print_text
ci-upstream-kasan-gce-smack-root 2021/01/22 03:16 upstream 9f29bd8b2e71 d4f4eca5 .config console log report info KASAN: global-out-of-bounds Write in record_print_text
ci-upstream-kasan-gce-386 2021/01/22 04:44 upstream 9f29bd8b2e71 d4f4eca5 .config console log report info KASAN: global-out-of-bounds Write in record_print_text
ci-upstream-linux-next-kasan-gce-root 2021/01/27 02:22 linux-next bc085f8fc88f 55a7d4df .config console log report info KASAN: global-out-of-bounds Write in record_print_text
ci-upstream-linux-next-kasan-gce-root 2021/01/26 10:22 linux-next bc085f8fc88f 52e37319 .config console log report info KASAN: global-out-of-bounds Write in record_print_text
ci-upstream-linux-next-kasan-gce-root 2021/01/24 16:52 linux-next bc085f8fc88f 52e37319 .config console log report info KASAN: global-out-of-bounds Write in record_print_text
ci-upstream-linux-next-kasan-gce-root 2021/01/24 16:52 linux-next bc085f8fc88f 52e37319 .config console log report info KASAN: global-out-of-bounds Write in record_print_text
ci-upstream-linux-next-kasan-gce-root 2021/01/23 21:23 linux-next bc085f8fc88f 52e37319 .config console log report info KASAN: global-out-of-bounds Write in record_print_text
ci-upstream-linux-next-kasan-gce-root 2021/01/23 00:42 linux-next bc085f8fc88f 4080af96 .config console log report info KASAN: global-out-of-bounds Write in record_print_text
ci-upstream-linux-next-kasan-gce-root 2021/01/23 00:33 linux-next bc085f8fc88f 4080af96 .config console log report info KASAN: global-out-of-bounds Write in record_print_text
ci-upstream-linux-next-kasan-gce-root 2021/01/21 21:08 linux-next bc085f8fc88f d4f4eca5 .config console log report info KASAN: global-out-of-bounds Write in record_print_text
ci-upstream-linux-next-kasan-gce-root 2021/01/21 21:05 linux-next bc085f8fc88f d4f4eca5 .config console log report info KASAN: global-out-of-bounds Write in record_print_text
ci-upstream-linux-next-kasan-gce-root 2021/01/21 21:05 linux-next bc085f8fc88f d4f4eca5 .config console log report info KASAN: global-out-of-bounds Write in record_print_text
* Struck through repros no longer work on HEAD.