Re: KASAN: stack-out-of-bounds Read in check_stack_object

[Dmitry Vyukov]

On Sun, Jan 6, 2019 at 2:31 PM syzbot
<syzbot+05fc3a636f5ee8830a99@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote:
>
> Hello,
>
> syzbot found the following crash on:
>
> HEAD commit:    3fed6ae4b027 ia64: fix compile without swiotlb
> git tree:       upstream
> console output: https://syzkaller.appspot.com/x/log.txt?x=161ce1d7400000
> kernel config:  https://syzkaller.appspot.com/x/.config?x=7308e68273924137
> dashboard link: https://syzkaller.appspot.com/bug?extid=05fc3a636f5ee8830a99
> compiler:       gcc (GCC) 9.0.0 20181231 (experimental)
> userspace arch: i386
> syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=10b3769f400000
>
> IMPORTANT: if you fix the bug, please add the following tag to the commit:
> Reported-by: syzbot+05fc3a636f5ee8830a99@xxxxxxxxxxxxxxxxxxxxxxxxx

I suspect this is another incarnation of:
https://syzkaller.appspot.com/bug?id=4821de869e3d78a255a034bf212a4e009f6125a7
Any other ideas?

> ------------[ cut here ]------------
> DEBUG_LOCKS_WARN_ON(current->hardirq_context)
> ------------[ cut here ]------------
> Bad or missing usercopy whitelist? Kernel memory overwrite attempt detected
> to SLAB object 'task_struct' (offset 912, size 2)!
> ==================================================================
> BUG: KASAN: stack-out-of-bounds in task_stack_page
> include/linux/sched/task_stack.h:21 [inline]
> BUG: KASAN: stack-out-of-bounds in check_stack_object+0x14e/0x160
> mm/usercopy.c:39
> list_add corruption. next->prev should be prev (ffff8880ae62d8d8), but was
> 0000000000000000. (next=ffff8880a94642f0).
> Read of size 8 at addr ffff8880a9464258 by task /-1455013312
> ------------[ cut here ]------------
>
> kernel BUG at lib/list_debug.c:23!
> CPU: 0 PID: -1455013312 Comm:  Not tainted 4.20.0+ #10
> invalid opcode: 0000 [#1] PREEMPT SMP KASAN
> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
> Google 01/01/2011
> CPU: 1 PID: 5941 Comm: syz-executor1 Not tainted 4.20.0+ #10
> Call Trace:
> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
> Google 01/01/2011
>
> RIP: 0010:__list_add_valid.cold+0xf/0x3c lib/list_debug.c:23
> Allocated by task 2570092928:
> Code: 34 fe eb d5 4c 89 e7 e8 2a dd 34 fe eb a3 4c 89 f7 e8 20 dd 34 fe e9
> 56 ff ff ff 4c 89 e1 48 c7 c7 60 b4 81 88 e8 f0 2d d7 fd <0f> 0b 48 89 f2
> 4c 89 e1 4c 89 ee 48 c7 c7 a0 b5 81 88 e8 d9 2d d7
> RSP: 0018:ffff8880ae707770 EFLAGS: 00010086
> RAX: 0000000000000075 RBX: ffff8880a3260730 RCX: 0000000000000000
> RDX: 0000000000000000 RSI: ffffffff81684c16 RDI: ffffed1015ce0ee0
> RBP: ffff8880ae707788 R08: 0000000000000075 R09: ffffed1015ce5021
> R10: ffffed1015ce5020 R11: ffff8880ae728107 R12: ffff8880a94642f0
> R13: ffff8880a3260730 R14: ffff8880ae62d8d8 R15: ffff8880ae707ad0
> FS:  0000000000000000(0000) GS:ffff8880ae700000(0063) knlGS:00000000f7fbbb40
> CS:  0010 DS: 002b ES: 002b CR0: 0000000080050033
> CR2: 0000000000625208 CR3: 00000000a57b8000 CR4: 00000000001406e0
> DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
> DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
> Call Trace:
>   <IRQ>
>   __list_add include/linux/list.h:60 [inline]
>   list_add include/linux/list.h:79 [inline]
>   list_move include/linux/list.h:171 [inline]
>   detach_tasks kernel/sched/fair.c:7557 [inline]
>   load_balance+0x1bdd/0x39d0 kernel/sched/fair.c:8979
>   rebalance_domains+0x815/0xf00 kernel/sched/fair.c:9366
>   run_rebalance_domains+0x376/0x4e0 kernel/sched/fair.c:9986
>   __do_softirq+0x30b/0xb11 kernel/softirq.c:292
>   invoke_softirq kernel/softirq.c:373 [inline]
>   irq_exit+0x180/0x1d0 kernel/softirq.c:413
>   exiting_irq arch/x86/include/asm/apic.h:536 [inline]
>   smp_apic_timer_interrupt+0x1b7/0x760 arch/x86/kernel/apic/apic.c:1062
>   apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:807
>   </IRQ>
> RIP: 0010:update_stack_state+0x24c/0x680 arch/x86/kernel/unwind_frame.c:244
> Code: 48 b9 00 00 00 00 00 fc ff df 4c 89 f6 48 c1 ee 03 80 3c 0e 00 0f 85
> b3 03 00 00 48 39 9d 30 ff ff ff 4d 8b 67 40 40 0f 97 c6 <4d> 85 e4 0f 95
> c1 40 84 ce 74 0c 39 85 44 ff ff ff 0f 84 68 01 00
> RSP: 0018:ffff88809870e768 EFLAGS: 00000283 ORIG_RAX: ffffffffffffff13
> RAX: 0000000000000001 RBX: ffff88809870ec58 RCX: dffffc0000000000
> RDX: ffff888098708000 RSI: 1ffff110130e1d00 RDI: ffff88809870e968
> RBP: ffff88809870e850 R08: 0000000000000001 R09: ffff88809870e9a8
> R10: ffff88809870e980 R11: ffff88809870e990 R12: ffff88809870e948
> R13: dffffc0000000000 R14: ffff88809870e998 R15: ffff88809870e958
>   unwind_next_frame.part.0+0x1ae/0xa90 arch/x86/kernel/unwind_frame.c:329
>   unwind_next_frame+0x3b/0x50 arch/x86/kernel/unwind_frame.c:287
>   __save_stack_trace+0x7a/0xf0 arch/x86/kernel/stacktrace.c:44
>   save_stack_trace+0x1a/0x20 arch/x86/kernel/stacktrace.c:60
>   save_stack+0x45/0xd0 mm/kasan/common.c:73
>   set_track mm/kasan/common.c:85 [inline]
>   kasan_kmalloc mm/kasan/common.c:482 [inline]
>   kasan_kmalloc+0xcf/0xe0 mm/kasan/common.c:455
>   kasan_slab_alloc+0xf/0x20 mm/kasan/common.c:397
>   slab_post_alloc_hook mm/slab.h:444 [inline]
>   slab_alloc_node mm/slab.c:3322 [inline]
>   kmem_cache_alloc_node_trace+0x13c/0x720 mm/slab.c:3648
>   __do_kmalloc_node mm/slab.c:3670 [inline]
>   __kmalloc_node_track_caller+0x3d/0x70 mm/slab.c:3685
>   __kmalloc_reserve.isra.0+0x40/0xe0 net/core/skbuff.c:140
>   __alloc_skb+0x12d/0x730 net/core/skbuff.c:208
>   alloc_skb include/linux/skbuff.h:1011 [inline]
>   alloc_skb_with_frags+0x13a/0x770 net/core/skbuff.c:5288
>   sock_alloc_send_pskb+0x8c9/0xad0 net/core/sock.c:2091
>   sock_alloc_send_skb+0x32/0x40 net/core/sock.c:2108
>   __ip6_append_data.isra.0+0x2556/0x3f20 net/ipv6/ip6_output.c:1443
>   ip6_make_skb+0x391/0x5f0 net/ipv6/ip6_output.c:1806
>   udpv6_sendmsg+0x2b58/0x3550 net/ipv6/udp.c:1460
>   inet_sendmsg+0x1af/0x740 net/ipv4/af_inet.c:798
>   sock_sendmsg_nosec net/socket.c:621 [inline]
>   sock_sendmsg+0xdd/0x130 net/socket.c:631
>   ___sys_sendmsg+0x409/0x910 net/socket.c:2116
>   __sys_sendmmsg+0x3bc/0x730 net/socket.c:2204
>   __compat_sys_sendmmsg net/compat.c:771 [inline]
>   __do_compat_sys_sendmmsg net/compat.c:778 [inline]
>   __se_compat_sys_sendmmsg net/compat.c:775 [inline]
>   __ia32_compat_sys_sendmmsg+0x9f/0x100 net/compat.c:775
>   do_syscall_32_irqs_on arch/x86/entry/common.c:326 [inline]
>   do_fast_syscall_32+0x333/0xf98 arch/x86/entry/common.c:397
>   entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139
> RIP: 0023:0xf7fbf869
> Code: 85 d2 74 02 89 0a 5b 5d c3 8b 04 24 c3 8b 14 24 c3 8b 3c 24 c3 90 90
> 90 90 90 90 90 90 90 90 90 90 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90
> 90 90 90 eb 0d 90 90 90 90 90 90 90 90 90 90 90 90
> RSP: 002b:00000000f7fbb0cc EFLAGS: 00000296 ORIG_RAX: 0000000000000159
> RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000020005fc0
> RDX: 00000000000000fc RSI: 0000000008000000 RDI: 0000000000000000
> RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
> R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
> R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
> Modules linked in:
> ---[ end trace e0e50d48068f1e3d ]---
> BUG: unable to handle kernel paging request at ffffffff8cf14780
> #PF error: [normal kernel read fault]
> RIP: 0010:__list_add_valid.cold+0xf/0x3c lib/list_debug.c:23
> PGD 9874067 P4D 9874067 PUD 9875063 PMD 0
> Code: 34 fe eb d5 4c 89 e7 e8 2a dd 34 fe eb a3 4c 89 f7 e8 20 dd 34 fe e9
> 56 ff ff ff 4c 89 e1 48 c7 c7 60 b4 81 88 e8 f0 2d d7 fd <0f> 0b 48 89 f2
> 4c 89 e1 4c 89 ee 48 c7 c7 a0 b5 81 88 e8 d9 2d d7
> Thread overran stack, or stack corrupted
> RSP: 0018:ffff8880ae707770 EFLAGS: 00010086
> Oops: 0000 [#2] PREEMPT SMP KASAN
> RAX: 0000000000000075 RBX: ffff8880a3260730 RCX: 0000000000000000
> CPU: 0 PID: -1455013312 Comm:  Tainted: G      D           4.20.0+ #10
> RDX: 0000000000000000 RSI: ffffffff81684c16 RDI: ffffed1015ce0ee0
> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
> Google 01/01/2011
> RBP: ffff8880ae707788 R08: 0000000000000075 R09: ffffed1015ce5021
> RIP: 0010:depot_fetch_stack+0x10/0x30 lib/stackdepot.c:202
> R10: ffffed1015ce5020 R11: ffff8880ae728107 R12: ffff8880a94642f0
> Code: e6 72 22 fe e9 20 fe ff ff 48 89 df e8 d9 72 22 fe e9 f1 fd ff ff 90
> 90 90 90 89 f8 c1 ef 11 25 ff ff 1f 00 81 e7 f0 3f 00 00 <48> 03 3c c5 80
> 03 f5 8b 8b 47 0c 48 83 c7 18 c7 46 10 00 00 00 00
> R13: ffff8880a3260730 R14: ffff8880ae62d8d8 R15: ffff8880ae707ad0
> RSP: 0018:ffff8880a9463fb8 EFLAGS: 00010006
> FS:  0000000000000000(0000) GS:ffff8880ae700000(0063) knlGS:00000000f7fbbb40
> RAX: 00000000001f8880 RBX: ffff8880a9465a04 RCX: 0000000000000000
> CS:  0010 DS: 002b ES: 002b CR0: 0000000080050033
> RDX: 0000000000000000 RSI: ffff8880a9463fc0 RDI: 0000000000003ff0
> CR2: 0000000000625208 CR3: 00000000a57b8000 CR4: 00000000001406e0
> RBP: ffff8880a9463fe8 R08: 000000000000001d R09: ffffed1015cc3ef9
> DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
> R10: ffffed1015cc3ef8 R11: ffff8880ae61f7c7 R12: ffffea0002a51900
> DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
> R13: ffff8880a9464258 R14: ffff8880aa13d900 R15: ffff8880a9465a00
>
>
> ---
> This bug is generated by a bot. It may contain errors.
> See https://goo.gl/tpsmEJ for more information about syzbot.
> syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxxx
>
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>
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