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UBSAN: array-index-out-of-bounds in qfq_update_agg (4)

Status: fixed on 2023/06/08 14:41
Subsystems: net
[Documentation on labels]
Fix commit: 3037933448f6 net: sched: sch_qfq: prevent slab-out-of-bounds in qfq_activate_agg
First crash: 363d, last: 363d
Similar bugs (3)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream UBSAN: array-index-out-of-bounds in qfq_update_agg (3) net 6 822d 934d 0/26 auto-closed as invalid on 2022/05/13 16:20
upstream UBSAN: array-index-out-of-bounds in qfq_update_agg (2) net 1 1054d 1054d 0/26 auto-closed as invalid on 2021/08/25 08:31
upstream UBSAN: array-index-out-of-bounds in qfq_update_agg net 2 1184d 1195d 0/26 auto-closed as invalid on 2021/05/16 21:20

Sample crash report:
================================================================================
UBSAN: array-index-out-of-bounds in net/sched/sch_qfq.c:300:24
index 29 is out of range for type 'qfq_group [25]'
CPU: 1 PID: 25903 Comm: syz-executor.2 Not tainted 6.3.0-rc7-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/30/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x136/0x150 lib/dump_stack.c:106
 ubsan_epilogue lib/ubsan.c:217 [inline]
 __ubsan_handle_out_of_bounds+0xd5/0x140 lib/ubsan.c:348
 qfq_update_agg+0x6e1/0x6f0 net/sched/sch_qfq.c:300
 qfq_add_to_agg+0x75/0x500 net/sched/sch_qfq.c:317
 qfq_change_class+0x66a/0x1650 net/sched/sch_qfq.c:508
 tc_ctl_tclass+0x5e2/0xf00 net/sched/sch_api.c:2126
 rtnetlink_rcv_msg+0x43d/0xd50 net/core/rtnetlink.c:6181
 netlink_rcv_skb+0x165/0x440 net/netlink/af_netlink.c:2577
 netlink_unicast_kernel net/netlink/af_netlink.c:1339 [inline]
 netlink_unicast+0x547/0x7f0 net/netlink/af_netlink.c:1365
 netlink_sendmsg+0x925/0xe30 net/netlink/af_netlink.c:1942
 sock_sendmsg_nosec net/socket.c:724 [inline]
 sock_sendmsg+0xde/0x190 net/socket.c:747
 ____sys_sendmsg+0x71c/0x900 net/socket.c:2501
 ___sys_sendmsg+0x110/0x1b0 net/socket.c:2555
 __sys_sendmsg+0xf7/0x1c0 net/socket.c:2584
 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline]
 __do_fast_syscall_32+0x65/0xf0 arch/x86/entry/common.c:178
 do_fast_syscall_32+0x33/0x70 arch/x86/entry/common.c:203
 entry_SYSENTER_compat_after_hwframe+0x70/0x82
RIP: 0023:0xf7f11579
Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00
RSP: 002b:00000000f7f0c5cc EFLAGS: 00000296 ORIG_RAX: 0000000000000172
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00000000200001c0
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>
================================================================================
----------------
Code disassembly (best guess), 2 bytes skipped:
   0:	10 06                	adc    %al,(%rsi)
   2:	03 74 b4 01          	add    0x1(%rsp,%rsi,4),%esi
   6:	10 07                	adc    %al,(%rdi)
   8:	03 74 b0 01          	add    0x1(%rax,%rsi,4),%esi
   c:	10 08                	adc    %cl,(%rax)
   e:	03 74 d8 01          	add    0x1(%rax,%rbx,8),%esi
  1e:	00 51 52             	add    %dl,0x52(%rcx)
  21:	55                   	push   %rbp
  22:	89 e5                	mov    %esp,%ebp
  24:	0f 34                	sysenter
  26:	cd 80                	int    $0x80
* 28:	5d                   	pop    %rbp <-- trapping instruction
  29:	5a                   	pop    %rdx
  2a:	59                   	pop    %rcx
  2b:	c3                   	retq
  2c:	90                   	nop
  2d:	90                   	nop
  2e:	90                   	nop
  2f:	90                   	nop
  30:	8d b4 26 00 00 00 00 	lea    0x0(%rsi,%riz,1),%esi
  37:	8d b4 26 00 00 00 00 	lea    0x0(%rsi,%riz,1),%esi

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/04/18 06:47 upstream 6a8f57ae2eb0 436577a9 .config console log report info ci-upstream-kasan-gce-386 UBSAN: array-index-out-of-bounds in qfq_update_agg
* Struck through repros no longer work on HEAD.