syzbot


general protection fault in qdisc_destroy

Status: fixed on 2019/12/09 13:28
Reported-by: syzbot+f18f2615be0576f2bf69@syzkaller.appspotmail.com
Fix commit: 7a1bad565ceb net_sched: let qdisc_put() accept NULL pointer
First crash: 1018d, last: 1007d

Fix bisection: fixed by (bisect log) :
commit 7a1bad565cebfbf6956f9bb36dba734a48fa31d4
Author: Cong Wang <xiyou.wangcong@gmail.com>
Date: Thu Sep 12 17:22:30 2019 +0000

  net_sched: let qdisc_put() accept NULL pointer

similar bugs (1):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.14 general protection fault in qdisc_destroy C done 4 1008d 1012d 1/1 fixed on 2019/12/09 13:28

Sample crash report:
IPv6: ADDRCONF(NETDEV_UP): vxcan1: link is not ready
8021q: adding VLAN 0 to HW filter on device batadv0
netlink: 'syz-executor157': attribute type 1 has an invalid length.
kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 7628 Comm: syz-executor157 Not tainted 4.19.74 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:qdisc_destroy+0x2f/0x690 net/sched/sch_generic.c:953
Code: 57 41 56 41 55 41 54 49 89 fc 53 48 83 ec 28 e8 97 36 ed fb 49 8d 7c 24 10 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <0f> b6 04 02 84 c0 74 08 3c 03 0f 8e d5 04 00 00 41 8b 5c 24 10 31
RSP: 0018:ffff88807e45f440 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: ffff888075a97680 RCX: 1ffff110120181bc
RDX: 0000000000000002 RSI: ffffffff857e2bf9 RDI: 0000000000000010
RBP: ffff88807e45f490 R08: ffff8880900c0540 R09: ffff8880900c0de0
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: ffff888075a97680 R14: ffff8880943ca980 R15: ffff888075a976bc
FS:  0000000000d0b880(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020000610 CR3: 00000000a821a000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 dsmark_destroy+0x63/0xd0 net/sched/sch_dsmark.c:415
 qdisc_create+0xaa6/0x1230 net/sched/sch_api.c:1203
 tc_modify_qdisc+0x51b/0x1bdc net/sched/sch_api.c:1570
 rtnetlink_rcv_msg+0x463/0xb00 net/core/rtnetlink.c:4747
 netlink_rcv_skb+0x17d/0x460 net/netlink/af_netlink.c:2454
 rtnetlink_rcv+0x1d/0x30 net/core/rtnetlink.c:4765
 netlink_unicast_kernel net/netlink/af_netlink.c:1317 [inline]
 netlink_unicast+0x537/0x720 net/netlink/af_netlink.c:1343
 netlink_sendmsg+0x8ae/0xd70 net/netlink/af_netlink.c:1908
 sock_sendmsg_nosec net/socket.c:622 [inline]
 sock_sendmsg+0xd7/0x130 net/socket.c:632
 ___sys_sendmsg+0x803/0x920 net/socket.c:2115
 __sys_sendmsg+0x105/0x1d0 net/socket.c:2153
 __do_sys_sendmsg net/socket.c:2162 [inline]
 __se_sys_sendmsg net/socket.c:2160 [inline]
 __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2160
 do_syscall_64+0xfd/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x441b19
Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 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 7b 10 fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007ffd8268f998 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000441b19
RDX: 0000000000000000 RSI: 0000000020000240 RDI: 0000000000000003
RBP: 00007ffd8268f9b0 R08: 0000000001bbbbbb R09: 0000000001bbbbbb
R10: 0000000001bbbbbb R11: 0000000000000246 R12: 0000000000000000
R13: 00000000004030b0 R14: 0000000000000000 R15: 0000000000000000
Modules linked in:
---[ end trace c18e0e2289bbad3f ]---
RIP: 0010:qdisc_destroy+0x2f/0x690 net/sched/sch_generic.c:953
Code: 57 41 56 41 55 41 54 49 89 fc 53 48 83 ec 28 e8 97 36 ed fb 49 8d 7c 24 10 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <0f> b6 04 02 84 c0 74 08 3c 03 0f 8e d5 04 00 00 41 8b 5c 24 10 31
RSP: 0018:ffff88807e45f440 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: ffff888075a97680 RCX: 1ffff110120181bc
RDX: 0000000000000002 RSI: ffffffff857e2bf9 RDI: 0000000000000010
RBP: ffff88807e45f490 R08: ffff8880900c0540 R09: ffff8880900c0de0
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: ffff888075a97680 R14: ffff8880943ca980 R15: ffff888075a976bc
FS:  0000000000d0b880(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020000610 CR3: 00000000a821a000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400

Crashes (9):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci2-linux-4-19 2019/09/20 16:44 linux-4.19.y dbc29aff8d04 d96e88f3 .config log report syz C
ci2-linux-4-19 2019/09/11 01:02 linux-4.19.y ee809c7e0895 a60cb4cd .config log report syz C
ci2-linux-4-19 2019/09/21 02:20 linux-4.19.y dbc29aff8d04 d96e88f3 .config log report
ci2-linux-4-19 2019/09/19 17:09 linux-4.19.y dbc29aff8d04 eb940044 .config log report
ci2-linux-4-19 2019/09/19 03:19 linux-4.19.y db2d0b7c1dde 46c0be24 .config log report
ci2-linux-4-19 2019/09/16 18:55 linux-4.19.y db2d0b7c1dde 55c50e70 .config log report
ci2-linux-4-19 2019/09/15 19:47 linux-4.19.y ee809c7e0895 32d59357 .config log report
ci2-linux-4-19 2019/09/13 07:20 linux-4.19.y ee809c7e0895 40fa42bc .config log report
ci2-linux-4-19 2019/09/11 00:22 linux-4.19.y ee809c7e0895 a60cb4cd .config log report