syzbot


KASAN: global-out-of-bounds Read in llc_conn_state_process

Status: auto-obsoleted due to no activity on 2024/05/10 14:15
Reported-by: syzbot+9ac3bf1c7b3a68b4a325@syzkaller.appspotmail.com
First crash: 313d, last: 313d
Similar bugs (3)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream UBSAN: array-index-out-of-bounds in llc_conn_state_process net 2 1003d 1117d 0/28 auto-closed as invalid on 2022/07/10 02:25
upstream UBSAN: array-index-out-of-bounds in llc_conn_state_process (2) net 10 34d 189d 0/28 upstream: reported on 2024/06/03 15:59
linux-6.1 general protection fault in llc_conn_state_process 1 103d 103d 0/3 auto-obsoleted due to no activity on 2024/12/06 20:07

Sample crash report:
==================================================================
BUG: KASAN: global-out-of-bounds in llc_qualify_conn_ev net/llc/llc_conn.c:399 [inline]
BUG: KASAN: global-out-of-bounds in llc_conn_service net/llc/llc_conn.c:365 [inline]
BUG: KASAN: global-out-of-bounds in llc_conn_state_process+0xf9/0x1220 net/llc/llc_conn.c:71
Read of size 8 at addr ffffffff8da09978 by task syz-executor.2/5434

CPU: 0 PID: 5434 Comm: syz-executor.2 Not tainted 5.15.148-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
 print_address_description+0x63/0x3b0 mm/kasan/report.c:248
 __kasan_report mm/kasan/report.c:434 [inline]
 kasan_report+0x16b/0x1c0 mm/kasan/report.c:451
 llc_qualify_conn_ev net/llc/llc_conn.c:399 [inline]
 llc_conn_service net/llc/llc_conn.c:365 [inline]
 llc_conn_state_process+0xf9/0x1220 net/llc/llc_conn.c:71
 llc_process_tmr_ev net/llc/llc_c_ac.c:1445 [inline]
 llc_conn_tmr_common_cb+0x347/0x8a0 net/llc/llc_c_ac.c:1331
 call_timer_fn+0x16d/0x560 kernel/time/timer.c:1421
 expire_timers kernel/time/timer.c:1466 [inline]
 __run_timers+0x67c/0x890 kernel/time/timer.c:1737
 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1750
 __do_softirq+0x3b3/0x93a kernel/softirq.c:558
 invoke_softirq kernel/softirq.c:432 [inline]
 __irq_exit_rcu+0x155/0x240 kernel/softirq.c:637
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:649
 sysvec_apic_timer_interrupt+0x91/0xb0 arch/x86/kernel/apic/apic.c:1096
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:161 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0xd4/0x130 kernel/locking/spinlock.c:194
Code: 9c 8f 44 24 20 42 80 3c 23 00 74 08 4c 89 f7 e8 42 db a3 f7 f6 44 24 21 02 75 4e 41 f7 c7 00 02 00 00 74 01 fb bf 01 00 00 00 <e8> 17 2e 31 f7 65 8b 05 d8 66 dc 75 85 c0 74 3f 48 c7 04 24 0e 36
RSP: 0018:ffffc90002fc75a0 EFLAGS: 00000206
RAX: 6d0dc1d40f75f800 RBX: 1ffff920005f8eb8 RCX: ffffffff8162ee28
RDX: dffffc0000000000 RSI: ffffffff8a8b0f80 RDI: 0000000000000001
RBP: ffffc90002fc7630 R08: dffffc0000000000 R09: fffffbfff1f7a02e
R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000
R13: 1ffff920005f8eb4 R14: ffffc90002fc75c0 R15: 0000000000000246
 spin_unlock_irqrestore include/linux/spinlock.h:418 [inline]
 __wake_up_common_lock kernel/sched/wait.c:140 [inline]
 __wake_up_sync_key+0x121/0x1c0 kernel/sched/wait.c:205
 __unix_dgram_recvmsg+0x5fe/0x1260 net/unix/af_unix.c:2343
 ____sys_recvmsg+0x286/0x530
 ___sys_recvmsg+0x1ec/0x690 net/socket.c:2692
 do_recvmmsg+0x36f/0x8f0 net/socket.c:2786
 __sys_recvmmsg net/socket.c:2865 [inline]
 __do_sys_recvmmsg net/socket.c:2888 [inline]
 __se_sys_recvmmsg net/socket.c:2881 [inline]
 __x64_sys_recvmmsg+0x195/0x240 net/socket.c:2881
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7fab8d81bda9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 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 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fab8bd7b0c8 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: ffffffffffffffda RBX: 00007fab8d94a050 RCX: 00007fab8d81bda9
RDX: 0000000000010106 RSI: 00000000200000c0 RDI: 0000000000000005
RBP: 00007fab8d86847a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000006e R14: 00007fab8d94a050 R15: 00007ffdbffcca78
 </TASK>

The buggy address belongs to the variable:
 llc_temp_state_transitions+0x58/0x60

Memory state around the buggy address:
 ffffffff8da09800: 00 00 00 00 00 00 00 00 00 f9 f9 f9 f9 f9 f9 f9
 ffffffff8da09880: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 f9 f9
>ffffffff8da09900: f9 f9 f9 f9 00 00 00 00 00 00 f9 f9 f9 f9 f9 f9
                                                                ^
 ffffffff8da09980: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffffffff8da09a00: 00 00 00 00 00 00 00 00 f9 f9 f9 f9 00 00 00 00
==================================================================
----------------
Code disassembly (best guess):
   0:	9c                   	pushf
   1:	8f 44 24 20          	pop    0x20(%rsp)
   5:	42 80 3c 23 00       	cmpb   $0x0,(%rbx,%r12,1)
   a:	74 08                	je     0x14
   c:	4c 89 f7             	mov    %r14,%rdi
   f:	e8 42 db a3 f7       	call   0xf7a3db56
  14:	f6 44 24 21 02       	testb  $0x2,0x21(%rsp)
  19:	75 4e                	jne    0x69
  1b:	41 f7 c7 00 02 00 00 	test   $0x200,%r15d
  22:	74 01                	je     0x25
  24:	fb                   	sti
  25:	bf 01 00 00 00       	mov    $0x1,%edi
* 2a:	e8 17 2e 31 f7       	call   0xf7312e46 <-- trapping instruction
  2f:	65 8b 05 d8 66 dc 75 	mov    %gs:0x75dc66d8(%rip),%eax        # 0x75dc670e
  36:	85 c0                	test   %eax,%eax
  38:	74 3f                	je     0x79
  3a:	48                   	rex.W
  3b:	c7                   	.byte 0xc7
  3c:	04 24                	add    $0x24,%al
  3e:	0e                   	(bad)
  3f:	36                   	ss

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/01/31 14:14 linux-5.15.y 6139f2a02fe0 373b66cd .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: global-out-of-bounds Read in llc_conn_state_process
* Struck through repros no longer work on HEAD.