syzbot


KASAN: null-ptr-deref Write in incfs_fresh_pending_reads_exist

Status: auto-closed as invalid on 2022/05/12 18:54
Reported-by: syzbot+0bd6b7e4b78b473c195e@syzkaller.appspotmail.com
First crash: 1013d, last: 1013d

Sample crash report:
==================================================================
BUG: KASAN: null-ptr-deref in instrument_atomic_read_write include/linux/instrumented.h:101 [inline]
BUG: KASAN: null-ptr-deref in atomic_try_cmpxchg_acquire include/asm-generic/atomic-instrumented.h:705 [inline]
BUG: KASAN: null-ptr-deref in queued_spin_lock include/asm-generic/qspinlock.h:82 [inline]
BUG: KASAN: null-ptr-deref in do_raw_spin_lock include/linux/spinlock.h:183 [inline]
BUG: KASAN: null-ptr-deref in __raw_spin_lock include/linux/spinlock_api_smp.h:143 [inline]
BUG: KASAN: null-ptr-deref in _raw_spin_lock+0x96/0x1b0 kernel/locking/spinlock.c:151
Write of size 4 at addr 0000000000000098 by task syz-executor.4/23064

CPU: 1 PID: 23064 Comm: syz-executor.4 Tainted: G        W         5.10.100-syzkaller-00843-g86e6176a4240 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack_lvl+0x1e2/0x24b lib/dump_stack.c:118
 __kasan_report+0x138/0x220 mm/kasan/report.c:423
 kasan_report+0x51/0x70 mm/kasan/report.c:436
 check_region_inline mm/kasan/generic.c:135 [inline]
 kasan_check_range+0x2b6/0x2f0 mm/kasan/generic.c:186
 __kasan_check_write+0x14/0x20 mm/kasan/shadow.c:37
 instrument_atomic_read_write include/linux/instrumented.h:101 [inline]
 atomic_try_cmpxchg_acquire include/asm-generic/atomic-instrumented.h:705 [inline]
 queued_spin_lock include/asm-generic/qspinlock.h:82 [inline]
 do_raw_spin_lock include/linux/spinlock.h:183 [inline]
 __raw_spin_lock include/linux/spinlock_api_smp.h:143 [inline]
 _raw_spin_lock+0x96/0x1b0 kernel/locking/spinlock.c:151
 spin_lock include/linux/spinlock.h:354 [inline]
 incfs_fresh_pending_reads_exist+0x32/0xe0 fs/incfs/data_mgmt.c:1738
 pending_reads_poll+0x13a/0x170 fs/incfs/pseudo_files.c:113
 vfs_poll include/linux/poll.h:90 [inline]
 do_pollfd fs/select.c:872 [inline]
 do_poll fs/select.c:920 [inline]
 do_sys_poll+0x8b2/0x12f0 fs/select.c:1014
 __do_sys_ppoll fs/select.c:1120 [inline]
 __se_sys_ppoll+0x29c/0x330 fs/select.c:1100
 __x64_sys_ppoll+0xbf/0xd0 fs/select.c:1100
 do_syscall_64+0x31/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x7f8b3c3bc059
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f8b3b532168 EFLAGS: 00000246 ORIG_RAX: 000000000000010f
RAX: ffffffffffffffda RBX: 00007f8b3c4cef60 RCX: 00007f8b3c3bc059
RDX: 0000000020000140 RSI: 0000000000000001 RDI: 0000000020000100
RBP: 00007f8b3c41608d R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffe880018ef R14: 00007f8b3b532300 R15: 0000000000022000
==================================================================
BUG: kernel NULL pointer dereference, address: 0000000000000098
#PF: supervisor write access in kernel mode
#PF: error_code(0x0002) - not-present page
PGD 1498a9067 P4D 1498a9067 PUD 10fd41067 PMD 0 
Oops: 0002 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 23064 Comm: syz-executor.4 Tainted: G    B   W         5.10.100-syzkaller-00843-g86e6176a4240 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:arch_atomic_try_cmpxchg arch/x86/include/asm/atomic.h:202 [inline]
RIP: 0010:atomic_try_cmpxchg_acquire include/asm-generic/atomic-instrumented.h:707 [inline]
RIP: 0010:queued_spin_lock include/asm-generic/qspinlock.h:82 [inline]
RIP: 0010:do_raw_spin_lock include/linux/spinlock.h:183 [inline]
RIP: 0010:__raw_spin_lock include/linux/spinlock_api_smp.h:143 [inline]
RIP: 0010:_raw_spin_lock+0xb8/0x1b0 kernel/locking/spinlock.c:151
Code: 00 00 00 e8 7a 8f 08 fd 4c 89 ff be 04 00 00 00 e8 6d 8f 08 fd 43 8a 04 26 84 c0 0f 85 a9 00 00 00 8b 44 24 20 b9 01 00 00 00 <f0> 41 0f b1 4d 00 75 33 48 c7 04 24 0e 36 e0 45 49 c7 04 1c 00 00
RSP: 0018:ffffc90000d07740 EFLAGS: 00010297
RAX: 0000000000000000 RBX: 1ffff920001a0ee8 RCX: 0000000000000001
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffc90000d07760
RBP: ffffc90000d077d8 R08: dffffc0000000000 R09: 0000000000000003
R10: fffff520001a0eed R11: 0000000000000004 R12: dffffc0000000000
R13: 0000000000000098 R14: 1ffff920001a0eec R15: ffffc90000d07760
FS:  00007f8b3b532700(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000098 CR3: 000000011c8ae000 CR4: 00000000003506a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 spin_lock include/linux/spinlock.h:354 [inline]
 incfs_fresh_pending_reads_exist+0x32/0xe0 fs/incfs/data_mgmt.c:1738
 pending_reads_poll+0x13a/0x170 fs/incfs/pseudo_files.c:113
 vfs_poll include/linux/poll.h:90 [inline]
 do_pollfd fs/select.c:872 [inline]
 do_poll fs/select.c:920 [inline]
 do_sys_poll+0x8b2/0x12f0 fs/select.c:1014
 __do_sys_ppoll fs/select.c:1120 [inline]
 __se_sys_ppoll+0x29c/0x330 fs/select.c:1100
 __x64_sys_ppoll+0xbf/0xd0 fs/select.c:1100
 do_syscall_64+0x31/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x7f8b3c3bc059
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f8b3b532168 EFLAGS: 00000246 ORIG_RAX: 000000000000010f
RAX: ffffffffffffffda RBX: 00007f8b3c4cef60 RCX: 00007f8b3c3bc059
RDX: 0000000020000140 RSI: 0000000000000001 RDI: 0000000020000100
RBP: 00007f8b3c41608d R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffe880018ef R14: 00007f8b3b532300 R15: 0000000000022000
Modules linked in:
CR2: 0000000000000098
---[ end trace 354173403a1039ee ]---
RIP: 0010:arch_atomic_try_cmpxchg arch/x86/include/asm/atomic.h:202 [inline]
RIP: 0010:atomic_try_cmpxchg_acquire include/asm-generic/atomic-instrumented.h:707 [inline]
RIP: 0010:queued_spin_lock include/asm-generic/qspinlock.h:82 [inline]
RIP: 0010:do_raw_spin_lock include/linux/spinlock.h:183 [inline]
RIP: 0010:__raw_spin_lock include/linux/spinlock_api_smp.h:143 [inline]
RIP: 0010:_raw_spin_lock+0xb8/0x1b0 kernel/locking/spinlock.c:151
Code: 00 00 00 e8 7a 8f 08 fd 4c 89 ff be 04 00 00 00 e8 6d 8f 08 fd 43 8a 04 26 84 c0 0f 85 a9 00 00 00 8b 44 24 20 b9 01 00 00 00 <f0> 41 0f b1 4d 00 75 33 48 c7 04 24 0e 36 e0 45 49 c7 04 1c 00 00
RSP: 0018:ffffc90000d07740 EFLAGS: 00010297
RAX: 0000000000000000 RBX: 1ffff920001a0ee8 RCX: 0000000000000001
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffc90000d07760
RBP: ffffc90000d077d8 R08: dffffc0000000000 R09: 0000000000000003
R10: fffff520001a0eed R11: 0000000000000004 R12: dffffc0000000000
R13: 0000000000000098 R14: 1ffff920001a0eec R15: ffffc90000d07760
FS:  00007f8b3b532700(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000098 CR3: 000000011c8ae000 CR4: 00000000003506a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	00 00                	add    %al,(%rax)
   2:	00 e8                	add    %ch,%al
   4:	7a 8f                	jp     0xffffff95
   6:	08 fd                	or     %bh,%ch
   8:	4c 89 ff             	mov    %r15,%rdi
   b:	be 04 00 00 00       	mov    $0x4,%esi
  10:	e8 6d 8f 08 fd       	callq  0xfd088f82
  15:	43 8a 04 26          	mov    (%r14,%r12,1),%al
  19:	84 c0                	test   %al,%al
  1b:	0f 85 a9 00 00 00    	jne    0xca
  21:	8b 44 24 20          	mov    0x20(%rsp),%eax
  25:	b9 01 00 00 00       	mov    $0x1,%ecx
* 2a:	f0 41 0f b1 4d 00    	lock cmpxchg %ecx,0x0(%r13) <-- trapping instruction
  30:	75 33                	jne    0x65
  32:	48 c7 04 24 0e 36 e0 	movq   $0x45e0360e,(%rsp)
  39:	45
  3a:	49                   	rex.WB
  3b:	c7                   	.byte 0xc7
  3c:	04 1c                	add    $0x1c,%al

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2022/02/11 18:45 android12-5.10-lts 86e6176a4240 8b9ca619 .config console log report info ci2-android-5-10 KASAN: null-ptr-deref Write in incfs_fresh_pending_reads_exist
* Struck through repros no longer work on HEAD.