device-mapper: raid: Choosing default region size of 4MiB
mdX: WARNING: ram1 appears to be on the same physical disk as ram1.
True protection against single-disk failure might be compromised.
FAULT_INJECTION: forcing a failure.
name fail_page_alloc, interval 1, probability 0, space 0, times 1
CPU: 0 UID: 0 PID: 5345 Comm: syz.0.0 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
 fail_dump lib/fault-inject.c:74 [inline]
 should_fail_ex+0x3eb/0x540 lib/fault-inject.c:175
 prepare_alloc_pages+0x21e/0x5f0 mm/page_alloc.c:5125
 __alloc_frozen_pages_noprof+0x17c/0x410 mm/page_alloc.c:5429
 alloc_pages_mpol+0x21e/0x390 mm/mempolicy.c:2511
 ___kmalloc_large_node+0x7b/0x170 mm/slub.c:5470
 __kmalloc_large_noprof+0x1a/0x90 mm/slub.c:5492
 _kmalloc_noprof include/linux/slab.h:988 [inline]
 _kzalloc_noprof include/linux/slab.h:1312 [inline]
 setup_conf+0x420/0x2ad0 drivers/md/raid5.c:7685
 raid5_run+0x8cc/0x2560 drivers/md/raid5.c:8129
 md_run+0xc3d/0x1cd0 drivers/md/md.c:6779
 raid_ctr+0x1895/0x2a80 drivers/md/dm-raid.c:3261
 dm_table_add_target+0x58d/0xc70 drivers/md/dm-table.c:749
 populate_table drivers/md/dm-ioctl.c:1602 [inline]
 table_load+0x325/0x8a0 drivers/md/dm-ioctl.c:1645
 ctl_ioctl drivers/md/dm-ioctl.c:2221 [inline]
 dm_ctl_ioctl+0x9ec/0xe10 drivers/md/dm-ioctl.c:2243
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:597 [inline]
 __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f92e399f559
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f92e4828fe8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f92e3c25fa0 RCX: 00007f92e399f559
RDX: 00002000000005c0 RSI: 00000000c138fd09 RDI: 0000000000000005
RBP: 00007f92e3a36b20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f92e3c26038 R14: 00007f92e3c25fa0 R15: 00007fffa342ea18
 </TASK>
==================================================================
BUG: KASAN: null-ptr-deref in instrument_atomic_read include/linux/instrumented.h:82 [inline]
BUG: KASAN: null-ptr-deref in _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline]
BUG: KASAN: null-ptr-deref in raid5_has_ppl drivers/md/raid5-log.h:54 [inline]
BUG: KASAN: null-ptr-deref in log_exit drivers/md/raid5-log.h:128 [inline]
BUG: KASAN: null-ptr-deref in free_conf+0x81/0x5d0 drivers/md/raid5.c:7549
Read of size 8 at addr 0000000000000028 by task syz.0.0/5345

CPU: 0 UID: 0 PID: 5345 Comm: syz.0.0 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
 kasan_report+0x117/0x150 mm/kasan/report.c:595
 check_region_inline mm/kasan/generic.c:-1 [inline]
 kasan_check_range+0x264/0x2c0 mm/kasan/generic.c:200
 instrument_atomic_read include/linux/instrumented.h:82 [inline]
 _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline]
 raid5_has_ppl drivers/md/raid5-log.h:54 [inline]
 log_exit drivers/md/raid5-log.h:128 [inline]
 free_conf+0x81/0x5d0 drivers/md/raid5.c:7549
 setup_conf+0x1720/0x2ad0 drivers/md/raid5.c:7885
 raid5_run+0x8cc/0x2560 drivers/md/raid5.c:8129
 md_run+0xc3d/0x1cd0 drivers/md/md.c:6779
 raid_ctr+0x1895/0x2a80 drivers/md/dm-raid.c:3261
 dm_table_add_target+0x58d/0xc70 drivers/md/dm-table.c:749
 populate_table drivers/md/dm-ioctl.c:1602 [inline]
 table_load+0x325/0x8a0 drivers/md/dm-ioctl.c:1645
 ctl_ioctl drivers/md/dm-ioctl.c:2221 [inline]
 dm_ctl_ioctl+0x9ec/0xe10 drivers/md/dm-ioctl.c:2243
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:597 [inline]
 __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f92e399f559
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f92e4828fe8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f92e3c25fa0 RCX: 00007f92e399f559
RDX: 00002000000005c0 RSI: 00000000c138fd09 RDI: 0000000000000005
RBP: 00007f92e3a36b20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f92e3c26038 R14: 00007f92e3c25fa0 R15: 00007fffa342ea18
 </TASK>
==================================================================