syzbot


BUG: unable to handle kernel NULL pointer dereference in net_rx_queue_update_kobjects

Status: fixed on 2020/07/17 17:58
Subsystems: net
[Documentation on labels]
Fix commit: 3021e69219e2 kcov: check kcov_softirq in kcov_remote_stop()
First crash: 1407d, last: 1407d

Sample crash report:
BUG: kernel NULL pointer dereference, address: 0000000000000000
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD a5311067 P4D a5311067 PUD 954c1067 PMD 0 
Oops: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 28725 Comm: syz-executor.5 Not tainted 5.7.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:__read_once_size include/linux/compiler.h:252 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x3f/0x60 kernel/kcov.c:202
Code: c2 00 01 ff 00 74 11 f7 c2 00 01 00 00 74 35 83 b9 04 14 00 00 00 74 2c 8b 91 e0 13 00 00 83 fa 02 75 21 48 8b 91 e8 13 00 00 <48> 8b 32 48 8d 7e 01 8b 89 e4 13 00 00 48 39 cf 73 08 48 89 44 f2
RSP: 0018:ffffc900083d7a28 EFLAGS: 00010246
RAX: ffffffff83bad453 RBX: ffff8880687c8093 RCX: ffff8880a754c480
RDX: 0000000000000000 RSI: 0000000000000074 RDI: 0000000000000000
RBP: 0000000000000013 R08: ffffffff83bad43e R09: ffffffff83ba9d62
R10: 0000000000000012 R11: ffff8880a754c480 R12: 0000000000000074
R13: ffff8880957e2142 R14: 00000000fffffffe R15: dffffc0000000000
FS:  00007f478630c700(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 00000000a7731000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 string_nocheck lib/vsprintf.c:612 [inline]
 string+0xb3/0x2c0 lib/vsprintf.c:690
 vsnprintf+0xf36/0x1aa0 lib/vsprintf.c:2620
 add_uevent_var+0x10a/0x2b0 lib/kobject_uevent.c:664
 kobject_uevent_env+0x310/0x11d0 lib/kobject_uevent.c:538
 rx_queue_add_kobject net/core/net-sysfs.c:970 [inline]
 net_rx_queue_update_kobjects+0x1df/0x440 net/core/net-sysfs.c:1010
 register_queue_kobjects net/core/net-sysfs.c:1644 [inline]
 netdev_register_kobject+0x1fb/0x2e0 net/core/net-sysfs.c:1892
 register_netdevice+0x1188/0x1a50 net/core/dev.c:9510
 tun_set_iff drivers/net/tun.c:2817 [inline]
 __tun_chr_ioctl+0x3028/0x45f0 drivers/net/tun.c:3054
 vfs_ioctl fs/ioctl.c:47 [inline]
 ksys_ioctl fs/ioctl.c:771 [inline]
 __do_sys_ioctl fs/ioctl.c:780 [inline]
 __se_sys_ioctl+0xf9/0x160 fs/ioctl.c:778
 do_syscall_64+0xf3/0x1b0 arch/x86/entry/common.c:295
 entry_SYSCALL_64_after_hwframe+0x49/0xb3
RIP: 0033:0x45ca59
Code: 0d b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 db b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f478630bc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00000000004efe60 RCX: 000000000045ca59
RDX: 00000000200000c0 RSI: 00000000400454ca RDI: 0000000000000003
RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000000005b2 R14: 00000000004c8716 R15: 00007f478630c6d4
Modules linked in:
CR2: 0000000000000000
---[ end trace ace9124737c7bba1 ]---
RIP: 0010:__read_once_size include/linux/compiler.h:252 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x3f/0x60 kernel/kcov.c:202
Code: c2 00 01 ff 00 74 11 f7 c2 00 01 00 00 74 35 83 b9 04 14 00 00 00 74 2c 8b 91 e0 13 00 00 83 fa 02 75 21 48 8b 91 e8 13 00 00 <48> 8b 32 48 8d 7e 01 8b 89 e4 13 00 00 48 39 cf 73 08 48 89 44 f2
RSP: 0018:ffffc900083d7a28 EFLAGS: 00010246
RAX: ffffffff83bad453 RBX: ffff8880687c8093 RCX: ffff8880a754c480
RDX: 0000000000000000 RSI: 0000000000000074 RDI: 0000000000000000
RBP: 0000000000000013 R08: ffffffff83bad43e R09: ffffffff83ba9d62
R10: 0000000000000012 R11: ffff8880a754c480 R12: 0000000000000074
R13: ffff8880957e2142 R14: 00000000fffffffe R15: dffffc0000000000
FS:  00007f478630c700(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000564b83aa5a10 CR3: 00000000a7731000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/06/17 10:28 upstream 7ae77150d94d b9f3810b .config console log report ci-upstream-kasan-gce-smack-root
* Struck through repros no longer work on HEAD.