==================================================================
BUG: KASAN: slab-use-after-free in __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
BUG: KASAN: slab-use-after-free in _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162
Read of size 1 at addr ffff88802583a818 by task kworker/0:2H/6170
CPU: 0 UID: 0 PID: 6170 Comm: kworker/0:2H Not tainted syzkaller #0 PREEMPT(full)
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Workqueue: events_highpri snd_vmidi_output_work
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:378 [inline]
print_report+0xcd/0x630 mm/kasan/report.c:482
kasan_report+0xe0/0x110 mm/kasan/report.c:595
__kasan_check_byte+0x36/0x50 mm/kasan/common.c:580
kasan_check_byte include/linux/kasan.h:401 [inline]
lock_acquire kernel/locking/lockdep.c:5842 [inline]
lock_acquire+0xfc/0x350 kernel/locking/lockdep.c:5825
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162
p9_tag_remove net/9p/client.c:397 [inline]
p9_req_put net/9p/client.c:405 [inline]
p9_req_put+0xaf/0x250 net/9p/client.c:402
req_done+0x1dc/0x2e0 net/9p/trans_virtio.c:147
vring_interrupt drivers/virtio/virtio_ring.c:2718 [inline]
vring_interrupt+0x31e/0x400 drivers/virtio/virtio_ring.c:2693
__handle_irq_event_percpu+0x236/0x920 kernel/irq/handle.c:203
handle_irq_event_percpu kernel/irq/handle.c:240 [inline]
handle_irq_event+0xab/0x1e0 kernel/irq/handle.c:257
handle_edge_irq+0x3ca/0x9e0 kernel/irq/chip.c:855
generic_handle_irq_desc include/linux/irqdesc.h:173 [inline]
handle_irq arch/x86/kernel/irq.c:254 [inline]
call_irq_handler arch/x86/kernel/irq.c:310 [inline]
__common_interrupt+0xd0/0x2f0 arch/x86/kernel/irq.c:325
common_interrupt+0x61/0xe0 arch/x86/kernel/irq.c:318
asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:688
RIP: 0010:handle_softirqs+0x1dd/0x8e0 kernel/softirq.c:608
Code: 88 6c 24 26 4c 89 7c 24 18 48 c7 c7 20 ce 8b 8b e8 68 df e0 09 65 66 c7 05 46 54 24 12 00 00 e8 49 7c 47 00 fb bb ff ff ff ff <49> c7 c7 c0 c0 00 8e 41 0f bc dc 83 c3 01 0f 85 a4 00 00 00 e9 b1
RSP: 0000:ffffc90000007f28 EFLAGS: 00000206
RAX: 0000000000027d48 RBX: 00000000ffffffff RCX: 0000000000000002
RDX: 0000000000000000 RSI: ffffffff8da29329 RDI: ffffffff8bf078c0
RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000001
R10: ffffffff90824cd7 R11: 0000000000000001 R12: 0000000000000002
R13: 000000000000000a R14: 1ffff92000000fed R15: ffffed1004ecb490
__do_softirq kernel/softirq.c:656 [inline]
invoke_softirq kernel/softirq.c:496 [inline]
__irq_exit_rcu+0x109/0x170 kernel/softirq.c:723
irq_exit_rcu+0x9/0x30 kernel/softirq.c:739
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1052 [inline]
sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1052
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0x31/0x80 kernel/locking/spinlock.c:194
Code: f5 53 48 8b 74 24 10 48 89 fb 48 83 c7 18 e8 a6 f1 37 f6 48 89 df e8 8e 45 38 f6 f7 c5 00 02 00 00 75 23 9c 58 f6 c4 02 75 37 01 00 00 00 e8 b5 4d 28 f6 65 8b 05 7e d5 40 08 85 c0 74 16 5b
RSP: 0000:ffffc90006307b40 EFLAGS: 00000246
RAX: 0000000000000006 RBX: ffff888043bcb338 RCX: 0000000000000006
RDX: 0000000000000000 RSI: ffffffff8da29329 RDI: ffffffff8bf078c0
RBP: 0000000000000293 R08: 0000000000000001 R09: 0000000000000001
R10: ffffffff90824cd7 R11: 0000000000000000 R12: ffff888043bcb338
R13: 0000000000000293 R14: 0000000000000001 R15: ffff888049f4b800
spin_unlock_irqrestore include/linux/spinlock.h:406 [inline]
class_spinlock_irqsave_destructor include/linux/spinlock.h:585 [inline]
snd_rawmidi_transmit+0x117/0x160 sound/core/rawmidi.c:1486
snd_vmidi_output_work+0x111/0x390 sound/core/seq/seq_virmidi.c:151
process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3263
process_scheduled_works kernel/workqueue.c:3346 [inline]
worker_thread+0x6c8/0xf10 kernel/workqueue.c:3427
kthread+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x675/0x7d0 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Allocated by task 6191:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:56
kasan_save_track+0x14/0x30 mm/kasan/common.c:77
poison_kmalloc_redzone mm/kasan/common.c:400 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:417
kmalloc_noprof include/linux/slab.h:957 [inline]
p9_client_create+0xc7/0x11d0 net/9p/client.c:985
v9fs_session_init+0x1f7/0x1a80 fs/9p/v9fs.c:410
v9fs_mount+0xc5/0xa90 fs/9p/vfs_super.c:122
legacy_get_tree+0x10c/0x220 fs/fs_context.c:663
vfs_get_tree+0x8e/0x340 fs/super.c:1758
fc_mount fs/namespace.c:1199 [inline]
do_new_mount_fc fs/namespace.c:3642 [inline]
do_new_mount fs/namespace.c:3718 [inline]
path_mount+0x7b9/0x23a0 fs/namespace.c:4028
do_mount fs/namespace.c:4041 [inline]
__do_sys_mount fs/namespace.c:4229 [inline]
__se_sys_mount fs/namespace.c:4206 [inline]
__ia32_sys_mount+0x291/0x310 fs/namespace.c:4206
do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline]
__do_fast_syscall_32+0x7c/0x300 arch/x86/entry/syscall_32.c:306
do_fast_syscall_32+0x32/0x80 arch/x86/entry/syscall_32.c:331
entry_SYSENTER_compat_after_hwframe+0x84/0x8e
Freed by task 6191:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:56
kasan_save_track+0x14/0x30 mm/kasan/common.c:77
__kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:587
kasan_save_free_info mm/kasan/kasan.h:406 [inline]
poison_slab_object mm/kasan/common.c:252 [inline]
__kasan_slab_free+0x5f/0x80 mm/kasan/common.c:284
kasan_slab_free include/linux/kasan.h:234 [inline]
slab_free_hook mm/slub.c:2543 [inline]
slab_free mm/slub.c:6642 [inline]
kfree+0x2b8/0x6d0 mm/slub.c:6849
p9_client_create+0xa28/0x11d0 net/9p/client.c:1064
v9fs_session_init+0x1f7/0x1a80 fs/9p/v9fs.c:410
v9fs_mount+0xc5/0xa90 fs/9p/vfs_super.c:122
legacy_get_tree+0x10c/0x220 fs/fs_context.c:663
vfs_get_tree+0x8e/0x340 fs/super.c:1758
fc_mount fs/namespace.c:1199 [inline]
do_new_mount_fc fs/namespace.c:3642 [inline]
do_new_mount fs/namespace.c:3718 [inline]
path_mount+0x7b9/0x23a0 fs/namespace.c:4028
do_mount fs/namespace.c:4041 [inline]
__do_sys_mount fs/namespace.c:4229 [inline]
__se_sys_mount fs/namespace.c:4206 [inline]
__ia32_sys_mount+0x291/0x310 fs/namespace.c:4206
do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline]
__do_fast_syscall_32+0x7c/0x300 arch/x86/entry/syscall_32.c:306
do_fast_syscall_32+0x32/0x80 arch/x86/entry/syscall_32.c:331
entry_SYSENTER_compat_after_hwframe+0x84/0x8e
The buggy address belongs to the object at ffff88802583a800
which belongs to the cache kmalloc-512 of size 512
The buggy address is located 24 bytes inside of
freed 512-byte region [ffff88802583a800, ffff88802583aa00)
The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x25838
head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
anon flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801b442c80 0000000000000000 dead000000000001
raw: 0000000000000000 0000000080100010 00000000f5000000 0000000000000000
head: 00fff00000000040 ffff88801b442c80 0000000000000000 dead000000000001
head: 0000000000000000 0000000080100010 00000000f5000000 0000000000000000
head: 00fff00000000002 ffffea0000960e01 00000000ffffffff 00000000ffffffff
head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000004
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 2, migratetype Unmovable, gfp_mask 0xd2000(__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 1, tgid 1 (swapper/0), ts 8463428723, free_ts 0
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x1af/0x220 mm/page_alloc.c:1845
prep_new_page mm/page_alloc.c:1853 [inline]
get_page_from_freelist+0x10a3/0x3a30 mm/page_alloc.c:3879
__alloc_frozen_pages_noprof+0x25f/0x2470 mm/page_alloc.c:5178
alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2416
alloc_slab_page mm/slub.c:3059 [inline]
allocate_slab mm/slub.c:3232 [inline]
new_slab+0x24a/0x360 mm/slub.c:3286
___slab_alloc+0xd79/0x1a50 mm/slub.c:4655
__slab_alloc.constprop.0+0x63/0x110 mm/slub.c:4778
__slab_alloc_node mm/slub.c:4854 [inline]
slab_alloc_node mm/slub.c:5276 [inline]
__kmalloc_cache_noprof+0x477/0x780 mm/slub.c:5766
kmalloc_noprof include/linux/slab.h:957 [inline]
kzalloc_noprof include/linux/slab.h:1094 [inline]
device_private_init drivers/base/core.c:3534 [inline]
device_add+0xccc/0x1aa0 drivers/base/core.c:3585
device_create_groups_vargs+0x1f8/0x270 drivers/base/core.c:4371
device_create+0xed/0x130 drivers/base/core.c:4410
bdi_register_va+0x114/0x820 mm/backing-dev.c:1099
bdi_register+0xc7/0x100 mm/backing-dev.c:1131
__add_disk+0xb0b/0xf00 block/genhd.c:533
add_disk_fwnode+0x13f/0x5d0 block/genhd.c:597
add_disk include/linux/blkdev.h:775 [inline]
loop_add+0x903/0xb70 drivers/block/loop.c:2090
page_owner free stack trace missing
Memory state around the buggy address:
ffff88802583a700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff88802583a780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88802583a800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff88802583a880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff88802583a900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
----------------
Code disassembly (best guess):
0: 88 6c 24 26 mov %ch,0x26(%rsp)
4: 4c 89 7c 24 18 mov %r15,0x18(%rsp)
9: 48 c7 c7 20 ce 8b 8b mov $0xffffffff8b8bce20,%rdi
10: e8 68 df e0 09 call 0x9e0df7d
15: 65 66 c7 05 46 54 24 movw $0x0,%gs:0x12245446(%rip) # 0x12245465
1c: 12 00 00
1f: e8 49 7c 47 00 call 0x477c6d
24: fb sti
25: bb ff ff ff ff mov $0xffffffff,%ebx
* 2a: 49 c7 c7 c0 c0 00 8e mov $0xffffffff8e00c0c0,%r15 <-- trapping instruction
31: 41 0f bc dc bsf %r12d,%ebx
35: 83 c3 01 add $0x1,%ebx
38: 0f 85 a4 00 00 00 jne 0xe2
3e: e9 .byte 0xe9
3f: b1 .byte 0xb1