syzbot


KASAN: out-of-bounds Read in update_curr

Status: fixed on 2019/03/06 07:43
Subsystems: hardening mm
[Documentation on labels]
Fix commit: 44039e00171b fou6: Prevent unbounded recursion in GUE error handler
First crash: 2101d, last: 2101d

Sample crash report:
8021q: adding VLAN 0 to HW filter on device batadv0
------------[ cut here ]------------
==================================================================
DEBUG_LOCKS_WARN_ON(current->hardirq_context)
------------[ cut here ]------------
BUG: KASAN: out-of-bounds in calc_delta_fair kernel/sched/fair.c:629 [inline]
BUG: KASAN: out-of-bounds in update_curr+0x99d/0xbc0 kernel/sched/fair.c:823
Bad or missing usercopy whitelist? Kernel memory overwrite attempt detected to SLAB object 'task_struct' (offset 912, size 2)!
Read of size 8 at addr ffff8880a94642c0 by task syz-executor5/8124
WARNING: CPU: 0 PID: -1455013312 at mm/usercopy.c:78 usercopy_warn+0xeb/0x110 mm/usercopy.c:78

Kernel panic - not syncing: panic_on_warn set ...
CPU: 1 PID: 8124 Comm: syz-executor5 Not tainted 4.20.0+ #10
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+0x1db/0x2d0 lib/dump_stack.c:113
 print_address_description.cold+0x7c/0x20d mm/kasan/report.c:187
 kasan_report.cold+0x1b/0x40 mm/kasan/report.c:317
 __asan_report_load8_noabort+0x14/0x20 mm/kasan/generic_report.c:135
 calc_delta_fair kernel/sched/fair.c:629 [inline]
 update_curr+0x99d/0xbc0 kernel/sched/fair.c:823
 enqueue_entity+0x3e5/0x20b0 kernel/sched/fair.c:3880
 enqueue_task_fair+0x237/0x10c0 kernel/sched/fair.c:5133
 enqueue_task kernel/sched/core.c:730 [inline]
 activate_task+0x11d/0x470 kernel/sched/core.c:751
 ttwu_activate kernel/sched/core.c:1643 [inline]
 ttwu_do_activate+0xd4/0x1f0 kernel/sched/core.c:1702
 ttwu_queue kernel/sched/core.c:1847 [inline]
 try_to_wake_up+0x997/0x1480 kernel/sched/core.c:2057
 default_wake_function+0x30/0x50 kernel/sched/core.c:3710
 __wake_up_common+0x1d3/0x7d0 kernel/sched/wait.c:92
 __wake_up_locked+0x11/0x20 kernel/sched/wait.c:154
 ep_poll_callback+0x3c5/0x10a0 fs/eventpoll.c:1200
 __wake_up_common+0x1d3/0x7d0 kernel/sched/wait.c:92
 __wake_up_common_lock+0x1c6/0x390 kernel/sched/wait.c:121
 __wake_up_sync_key+0x19/0x20 kernel/sched/wait.c:199
 pipe_write+0x960/0xfb0 fs/pipe.c:477
 call_write_iter include/linux/fs.h:1862 [inline]
 new_sync_write fs/read_write.c:474 [inline]
 __vfs_write+0x764/0xb40 fs/read_write.c:487
 vfs_write+0x20c/0x580 fs/read_write.c:549
 ksys_write+0x105/0x260 fs/read_write.c:598
 __do_sys_write fs/read_write.c:610 [inline]
 __se_sys_write fs/read_write.c:607 [inline]
 __x64_sys_write+0x73/0xb0 fs/read_write.c:607
 do_syscall_64+0x1a3/0x800 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x411bb0
Code: b0 89 c8 f7 d8 eb ed b8 6e 00 00 00 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 83 3d dd 46 64 00 00 75 14 b8 01 00 00 00 0f 05 <48> 3d 01 f0 ff ff 0f 83 54 1a 00 00 c3 48 83 ec 08 e8 ca fc ff ff
RSP: 002b:00007fff30c9a788 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 000000000001b1d4 RCX: 0000000000411bb0
RDX: 000000000000000c RSI: 00007fff30c9a790 RDI: 00000000000000f8
RBP: 0000000000000070 R08: 0000000000000001 R09: 0000000002829940
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000008
R13: 000000000001b111 R14: 000000000000001d R15: 0000000000000005

CPU: 0 PID: -1455013312 Comm:  Not tainted 4.20.0+ #10
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Allocated by task 2679210176:
Call Trace:
BUG: unable to handle kernel paging request at ffffffff8cf14780
#PF error: [normal kernel read fault]
PGD 9874067 P4D 9874067 PUD 9875063 PMD 0 
Oops: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 8124 Comm: syz-executor5 Not tainted 4.20.0+ #10
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:depot_fetch_stack+0x10/0x30 lib/stackdepot.c:202
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
RSP: 0018:ffff8880a57f6ed8 EFLAGS: 00010006
RAX: 00000000001f8880 RBX: ffff8880a9465a04 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffff8880a57f6ee0 RDI: 0000000000003ff0
RBP: ffff8880a57f6f08 R08: 000000000000001d R09: ffffed1015ce3ef9
R10: ffffed1015ce3ef8 R11: ffff8880ae71f7c7 R12: ffffea0002a51900
R13: ffff8880a94642c0 R14: ffff8880aa13d900 R15: ffff8880a9465a00
FS:  0000000002829940(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffff8cf14780 CR3: 00000000929d3000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 describe_object mm/kasan/report.c:158 [inline]
 print_address_description.cold+0x16a/0x20d mm/kasan/report.c:194
 kasan_report.cold+0x1b/0x40 mm/kasan/report.c:317
 __asan_report_load8_noabort+0x14/0x20 mm/kasan/generic_report.c:135
 calc_delta_fair kernel/sched/fair.c:629 [inline]
 update_curr+0x99d/0xbc0 kernel/sched/fair.c:823
 enqueue_entity+0x3e5/0x20b0 kernel/sched/fair.c:3880
 enqueue_task_fair+0x237/0x10c0 kernel/sched/fair.c:5133
 enqueue_task kernel/sched/core.c:730 [inline]
 activate_task+0x11d/0x470 kernel/sched/core.c:751
 ttwu_activate kernel/sched/core.c:1643 [inline]
 ttwu_do_activate+0xd4/0x1f0 kernel/sched/core.c:1702
 ttwu_queue kernel/sched/core.c:1847 [inline]
 try_to_wake_up+0x997/0x1480 kernel/sched/core.c:2057
 default_wake_function+0x30/0x50 kernel/sched/core.c:3710
 __wake_up_common+0x1d3/0x7d0 kernel/sched/wait.c:92
 __wake_up_locked+0x11/0x20 kernel/sched/wait.c:154
 ep_poll_callback+0x3c5/0x10a0 fs/eventpoll.c:1200
 __wake_up_common+0x1d3/0x7d0 kernel/sched/wait.c:92
 __wake_up_common_lock+0x1c6/0x390 kernel/sched/wait.c:121
 __wake_up_sync_key+0x19/0x20 kernel/sched/wait.c:199
 pipe_write+0x960/0xfb0 fs/pipe.c:477
 call_write_iter include/linux/fs.h:1862 [inline]
 new_sync_write fs/read_write.c:474 [inline]
 __vfs_write+0x764/0xb40 fs/read_write.c:487
 vfs_write+0x20c/0x580 fs/read_write.c:549
 ksys_write+0x105/0x260 fs/read_write.c:598
 __do_sys_write fs/read_write.c:610 [inline]
 __se_sys_write fs/read_write.c:607 [inline]
 __x64_sys_write+0x73/0xb0 fs/read_write.c:607
 do_syscall_64+0x1a3/0x800 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x411bb0
Code: b0 89 c8 f7 d8 eb ed b8 6e 00 00 00 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 83 3d dd 46 64 00 00 75 14 b8 01 00 00 00 0f 05 <48> 3d 01 f0 ff ff 0f 83 54 1a 00 00 c3 48 83 ec 08 e8 ca fc ff ff
RSP: 002b:00007fff30c9a788 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 000000000001b1d4 RCX: 0000000000411bb0
RDX: 000000000000000c RSI: 00007fff30c9a790 RDI: 00000000000000f8
RBP: 0000000000000070 R08: 0000000000000001 R09: 0000000002829940
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000008
R13: 000000000001b111 R14: 000000000000001d R15: 0000000000000005
Modules linked in:
CR2: ffffffff8cf14780
---[ end trace 638f4f89086ae982 ]---
RIP: 0010:depot_fetch_stack+0x10/0x30 lib/stackdepot.c:202
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
RSP: 0018:ffff8880a57f6ed8 EFLAGS: 00010006
RAX: 00000000001f8880 RBX: ffff8880a9465a04 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffff8880a57f6ee0 RDI: 0000000000003ff0
RBP: ffff8880a57f6f08 R08: 000000000000001d R09: ffffed1015ce3ef9
R10: ffffed1015ce3ef8 R11: ffff8880ae71f7c7 R12: ffffea0002a51900
R13: ffff8880a94642c0 R14: ffff8880aa13d900 R15: ffff8880a9465a00
FS:  0000000002829940(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffff8cf14780 CR3: 00000000929d3000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Shutting down cpus with NMI
usercopy: Kernel memory overwrite attempt detected to SLAB object 'sighand_cache' (offset 2320, size 2)!
------------[ cut here ]------------
kernel BUG at mm/usercopy.c:102!
WARNING: CPU: 0 PID: -1455013312 at kernel/rcu/tree_plugin.h:414 __rcu_read_lock+0x75/0x90 kernel/rcu/tree_plugin.h:416
Modules linked in:
CPU: 0 PID: -1455013312 Comm:  Tainted: G      D           4.20.0+ #10
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:__rcu_read_lock+0x75/0x90 kernel/rcu/tree_plugin.h:414
Code: 00 48 8d bb 70 03 00 00 48 89 fa 48 c1 ea 03 0f b6 04 02 84 c0 74 04 3c 03 7e 14 81 bb 70 03 00 00 ff ff ff 3f 7f 03 5b 5d c3 <0f> 0b 5b 5d c3 e8 c1 1c 5a 00 eb e5 e8 ba 1c 5a 00 eb aa 0f 1f 84
RSP: 0018:ffff8880a9463850 EFLAGS: 00010012
RAX: 0000000000000000 RBX: ffff8880a9464240 RCX: ffffffff816bca0f
RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffff8880a94645b0
RBP: ffff8880a9463858 R08: ffff8880a9464240 R09: 0000000000000004
R10: ffffed1015cc3ef8 R11: ffff8880ae61f7c7 R12: 0000000000000000
R13: 0000000000000008 R14: ffff8880a94638d0 R15: ffff8880a94639d8
FS:  0000000000000000(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020000000 CR3: 00000000a808b000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
irq event stamp: 2321362889
hardirqs last  enabled at (2170845055): [<ffffed101528c974>] 0xffffed101528c974
hardirqs last disabled at (2321362889): [<ffffffff81681cd9>] vprintk_emit+0x169/0x960 kernel/printk/printk.c:1911
softirqs last  enabled at (0): [<ffffffff86eb00a0>] gue6_err+0x0/0x6b0 net/ipv6/fou6.c:86
softirqs last disabled at (1): [<0000000000000001>] 0x1
---[ end trace 638f4f89086ae983 ]---
invalid opcode: 0000 [#2] PREEMPT SMP KASAN
CPU: 0 PID: -1455013312 Comm:  Tainted: G      D W         4.20.0+ #10
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:usercopy_abort+0xbd/0xbf mm/usercopy.c:102
Code: c0 e8 0d ca b1 ff 48 8b 55 c0 49 89 d9 4d 89 f0 ff 75 c8 4c 89 e1 4c 89 ee 48 c7 c7 40 37 55 88 ff 75 d0 41 57 e8 fd 09 98 ff <0f> 0b e8 e2 c9 b1 ff e8 dd af f5 ff 8b 95 20 ff ff ff 4c 89 e1 31
RSP: 0018:ffff8880a9463a80 EFLAGS: 00010086
RAX: 0000000000000068 RBX: ffffffff88494fa0 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff81684c16 RDI: ffffed101528c742
RBP: ffff8880a9463ad8 R08: 0000000000000068 R09: ffffed1015cc3ef9
R10: ffffed1015cc3ef8 R11: ffff8880ae61f7c7 R12: ffffffff893c9f1d
R13: ffffffff885535a0 R14: ffffffff885534e0 R15: ffffffff885534a0
FS:  0000000000000000(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020000000 CR3: 00000000a808b000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
Modules linked in:
---[ end trace 638f4f89086ae984 ]---
RIP: 0010:depot_fetch_stack+0x10/0x30 lib/stackdepot.c:202
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
RSP: 0018:ffff8880a57f6ed8 EFLAGS: 00010006
RAX: 00000000001f8880 RBX: ffff8880a9465a04 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffff8880a57f6ee0 RDI: 0000000000003ff0
RBP: ffff8880a57f6f08 R08: 000000000000001d R09: ffffed1015ce3ef9
R10: ffffed1015ce3ef8 R11: ffff8880ae71f7c7 R12: ffffea0002a51900
R13: ffff8880a94642c0 R14: ffff8880aa13d900 R15: ffff8880a9465a00
FS:  0000000000000000(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020000000 CR3: 00000000a808b000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2019/01/05 09:16 upstream 3fed6ae4b027 53be0a37 .config console log report syz ci-upstream-kasan-gce-root
* Struck through repros no longer work on HEAD.