KASAN: use-after-free Write in validate_chain

From: syzbot
Date: Fri Jun 21 2019 - 08:57:12 EST


Hello,

syzbot found the following crash on:

HEAD commit: abf02e29 Merge tag 'pm-5.2-rc6' of git://git.kernel.org/pu..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=128b8be6a00000
kernel config: https://syzkaller.appspot.com/x/.config?x=28ec3437a5394ee0
dashboard link: https://syzkaller.appspot.com/bug?extid=55c548ad445cef6063ab
compiler: clang version 9.0.0 (/home/glider/llvm/clang 80fee25776c2fb61e74c1ecb1a523375c2500b69)
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=128ce13aa00000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+55c548ad445cef6063ab@xxxxxxxxxxxxxxxxxxxxxxxxx

==================================================================
BUG: KASAN: use-after-free in check_prev_add kernel/locking/lockdep.c:2298 [inline]
BUG: KASAN: use-after-free in check_prevs_add kernel/locking/lockdep.c:2418 [inline]
BUG: KASAN: use-after-free in validate_chain+0x1a35/0x84f0 kernel/locking/lockdep.c:2800
Write of size 8 at addr ffff8880972652b0 by task syz-executor.3/9443

CPU: 1 PID: 9443 Comm: syz-executor.3 Not tainted 5.2.0-rc5+ #4
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:

Allocated by task 1172321806:
(stack is not available)

Freed by task 2287698508:
------------[ cut here ]------------
kernel BUG at mm/slab.c:4178!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 9443 Comm: syz-executor.3 Not tainted 5.2.0-rc5+ #4
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:__check_heap_object+0xcb/0xd0 mm/slab.c:4202
Code: 4c 89 d1 4d 89 c8 e8 44 4d 07 00 5b 41 5e 5d c3 49 8b 73 58 41 0f b6 d0 48 c7 c7 15 78 5d 88 4c 89 d1 4d 89 c8 e8 e5 4d 07 00 <0f> 0b 0f 1f 00 55 48 89 e5 41 56 53 48 83 ff 10 74 4a 48 89 fb 48
RSP: 0018:ffff8880972638b0 EFLAGS: 00010046
RAX: 0000000000000fa9 RBX: 00000000000011c0 RCX: 000000000000000c
RDX: 000000000000000c RSI: 0000000000000002 RDI: 0000000000000001
RBP: ffff8880972638c0 R08: 0000000000000000 R09: ffffffff81b5ce7a
R10: ffff8880972639c0 R11: ffff8880aa58f940 R12: ffff8880972639c2
R13: 0000000000000200 R14: ffff888097262800 R15: ffff8880972639c0
FS: 0000555556169940(0000) GS:ffff8880aeb00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffff8adea628 CR3: 00000000a5dc4000 CR4: 00000000001406e0
Call Trace:
Modules linked in:
---[ end trace 8685358c22a34005 ]---
RIP: 0010:__check_heap_object+0xcb/0xd0 mm/slab.c:4202
Code: 4c 89 d1 4d 89 c8 e8 44 4d 07 00 5b 41 5e 5d c3 49 8b 73 58 41 0f b6 d0 48 c7 c7 15 78 5d 88 4c 89 d1 4d 89 c8 e8 e5 4d 07 00 <0f> 0b 0f 1f 00 55 48 89 e5 41 56 53 48 83 ff 10 74 4a 48 89 fb 48
RSP: 0018:ffff8880972638b0 EFLAGS: 00010046
RAX: 0000000000000fa9 RBX: 00000000000011c0 RCX: 000000000000000c
RDX: 000000000000000c RSI: 0000000000000002 RDI: 0000000000000001
RBP: ffff8880972638c0 R08: 0000000000000000 R09: ffffffff81b5ce7a
R10: ffff8880972639c0 R11: ffff8880aa58f940 R12: ffff8880972639c2
R13: 0000000000000200 R14: ffff888097262800 R15: ffff8880972639c0
FS: 0000555556169940(0000) GS:ffff8880aeb00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffff8adea628 CR3: 00000000a5dc4000 CR4: 00000000001406e0


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