FAULT_INJECTION: forcing a failure.
name fail_page_alloc, interval 1, probability 0, space 0, times 0
==================================================================
BUG: KASAN: null-ptr-deref in atomic_inc include/asm-generic/atomic-instrumented.h:109 [inline]
BUG: KASAN: null-ptr-deref in kthread_stop+0x10d/0x900 kernel/kthread.c:545
Write of size 4 at addr 000000000000001c by task syz-executor3/13454

CPU: 0 PID: 13454 Comm: syz-executor3 Not tainted 4.20.0-rc7+ #383
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+0x1d3/0x2c6 lib/dump_stack.c:113
 kasan_report_error mm/kasan/report.c:352 [inline]
 kasan_report.cold.9+0x6d/0x309 mm/kasan/report.c:412
 check_memory_region_inline mm/kasan/kasan.c:260 [inline]
 check_memory_region+0x13e/0x1b0 mm/kasan/kasan.c:267
 kasan_check_write+0x14/0x20 mm/kasan/kasan.c:278
 atomic_inc include/asm-generic/atomic-instrumented.h:109 [inline]
 kthread_stop+0x10d/0x900 kernel/kthread.c:545
 vivid_stop_generating_vid_cap+0x2bb/0x9ae drivers/media/platform/vivid/vivid-kthread-cap.c:931
 vid_cap_stop_streaming+0x8d/0xe0 drivers/media/platform/vivid/vivid-vid-cap.c:259
 __vb2_queue_cancel+0x14f/0xd50 drivers/media/common/videobuf2/videobuf2-core.c:1843
 vb2_core_streamoff+0x60/0x140 drivers/media/common/videobuf2/videobuf2-core.c:2006
 __vb2_cleanup_fileio+0x73/0x160 drivers/media/common/videobuf2/videobuf2-core.c:2527
 vb2_core_queue_release+0x1e/0x80 drivers/media/common/videobuf2/videobuf2-core.c:2254
 vb2_queue_release drivers/media/common/videobuf2/videobuf2-v4l2.c:842 [inline]
 _vb2_fop_release+0x1d2/0x2b0 drivers/media/common/videobuf2/videobuf2-v4l2.c:1015
 vb2_fop_release+0x77/0xc0 drivers/media/common/videobuf2/videobuf2-v4l2.c:1029
 vivid_fop_release+0x18e/0x440 drivers/media/platform/vivid/vivid-core.c:474
 v4l2_release+0x224/0x3a0 drivers/media/v4l2-core/v4l2-dev.c:456
 __fput+0x385/0xa30 fs/file_table.c:278
 ____fput+0x15/0x20 fs/file_table.c:309
 task_work_run+0x1e8/0x2a0 kernel/task_work.c:113
 tracehook_notify_resume include/linux/tracehook.h:188 [inline]
 exit_to_usermode_loop+0x318/0x380 arch/x86/entry/common.c:166
 prepare_exit_to_usermode arch/x86/entry/common.c:197 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:268 [inline]
 do_syscall_64+0x6be/0x820 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x457669
Code: fd b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 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 0f 83 cb b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f698c36fc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 0000000000000001 RCX: 0000000000457669
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000004
RBP: 000000000072bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f698c3706d4
R13: 00000000004f1732 R14: 00000000004cd5b8 R15: 00000000ffffffff
==================================================================
CPU: 1 PID: 13458 Comm: syz-executor1 Tainted: G    B             4.20.0-rc7+ #383
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+0x1d3/0x2c6 lib/dump_stack.c:113
 fail_dump lib/fault-inject.c:51 [inline]
 should_fail.cold.4+0xa/0x17 lib/fault-inject.c:149
 should_fail_alloc_page mm/page_alloc.c:3068 [inline]
 prepare_alloc_pages mm/page_alloc.c:4320 [inline]
 __alloc_pages_nodemask+0x366/0xea0 mm/page_alloc.c:4367
 alloc_pages_current+0x10c/0x210 mm/mempolicy.c:2106
 alloc_pages include/linux/gfp.h:509 [inline]
 push_pipe+0x3ff/0x7a0 lib/iov_iter.c:520
 __pipe_get_pages lib/iov_iter.c:1217 [inline]
 pipe_get_pages_alloc lib/iov_iter.c:1324 [inline]
 iov_iter_get_pages_alloc+0x938/0x15a0 lib/iov_iter.c:1342
 default_file_splice_read+0x1db/0xb20 fs/splice.c:391
 do_splice_to+0x12e/0x190 fs/splice.c:880
 splice_direct_to_actor+0x31c/0x9d0 fs/splice.c:957
 do_splice_direct+0x2d4/0x420 fs/splice.c:1066
 do_sendfile+0x62a/0xe20 fs/read_write.c:1439
 __do_sys_sendfile64 fs/read_write.c:1500 [inline]
 __se_sys_sendfile64 fs/read_write.c:1486 [inline]
 __x64_sys_sendfile64+0x1fd/0x250 fs/read_write.c:1486
 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x457669
Code: fd b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 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 0f 83 cb b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f2f92649c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 00007f2f92649c90 RCX: 0000000000457669
RDX: 0000000000000000 RSI: 0000000000000004 RDI: 0000000000000005
RBP: 000000000072bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0079ffff00000011 R11: 0000000000000246 R12: 00007f2f9264a6d4
R13: 00000000004c3e42 R14: 00000000004d6c90 R15: 0000000000000006
IPv6: ADDRCONF(NETDEV_CHANGE): vcan0: link becomes ready