kobject: '(null)' (000000009582ecff): calling ktype release
elv: switch to "mq-deadline" failed, falling back to "none"
==================================================================
BUG: KASAN: slab-out-of-bounds in blk_mq_free_rqs+0xd8/0x628 block/blk-mq.c:-1
Read of size 8 at addr ffff0000ed46a968 by task syz.0.1488/11497

CPU: 0 UID: 0 PID: 11497 Comm: syz.0.1488 Not tainted syzkaller #0 PREEMPT 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/14/2026
dump_backtrace(regs = 0000000000000000 tsk = 0000000000000000)
Call trace:
 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:499 (C)
 __dump_stack+0x30/0x40 lib/dump_stack.c:94
 dump_stack_lvl+0xd8/0x12c lib/dump_stack.c:120
 print_address_description+0xb0/0x238 mm/kasan/report.c:378
 print_report+0x68/0x84 mm/kasan/report.c:482
 kasan_report+0x8c/0xc4 mm/kasan/report.c:595
 __asan_report_load8_noabort+0x20/0x2c mm/kasan/report_generic.c:381
 blk_mq_free_rqs+0xd8/0x628 block/blk-mq.c:-1
 blk_mq_free_map_and_rqs+0x3c/0x64 block/blk-mq.c:4148
 blk_mq_free_sched_tags+0xb8/0x178 block/blk-mq-sched.c:425
 blk_mq_free_sched_res+0x64/0x114 block/blk-mq-sched.c:436
 elv_update_nr_hw_queues+0x150/0x210 block/elevator.c:722
 blk_mq_elv_switch_back block/blk-mq.c:5057 [inline]
 __blk_mq_update_nr_hw_queues block/blk-mq.c:5187 [inline]
 blk_mq_update_nr_hw_queues+0xd0c/0x11e0 block/blk-mq.c:5212
 nbd_start_device+0x15c/0xa44 drivers/block/nbd.c:1530
 nbd_genl_connect+0xde4/0x12b0 drivers/block/nbd.c:2310
 genl_family_rcv_msg_doit+0x1e4/0x2d4 net/netlink/genetlink.c:1114
 genl_family_rcv_msg net/netlink/genetlink.c:1194 [inline]
 genl_rcv_msg+0x43c/0x620 net/netlink/genetlink.c:1209
 netlink_rcv_skb+0x238/0x414 net/netlink/af_netlink.c:2575
 genl_rcv+0x38/0x50 net/netlink/genetlink.c:1218
 netlink_unicast_kernel net/netlink/af_netlink.c:1338 [inline]
 netlink_unicast+0x600/0x7f8 net/netlink/af_netlink.c:1364
 netlink_sendmsg+0x648/0x948 net/netlink/af_netlink.c:1919
 sock_sendmsg_nosec net/socket.c:800 [inline]
 __sock_sendmsg+0xc8/0x17c net/socket.c:815
 ____sys_sendmsg+0x3d0/0x6c8 net/socket.c:2713
 ___sys_sendmsg+0x198/0x224 net/socket.c:2767
 __sys_sendmsg+0x158/0x204 net/socket.c:2799
 __do_sys_sendmsg net/socket.c:2804 [inline]
 __se_sys_sendmsg net/socket.c:2802 [inline]
 __arm64_sys_sendmsg+0x88/0x9c net/socket.c:2802
 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
 invoke_syscall+0x98/0x244 arch/arm64/kernel/syscall.c:49
 el0_svc_common+0xec/0x23c arch/arm64/kernel/syscall.c:121
 do_el0_svc+0x4c/0x5c arch/arm64/kernel/syscall.c:140
 el0_svc+0x60/0x1d8 arch/arm64/kernel/entry-common.c:796
 el0t_64_sync_handler+0x44/0x104 arch/arm64/kernel/entry-common.c:815
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:606

Allocated by task 11105:
 kasan_save_stack mm/kasan/common.c:57 [inline]
 kasan_save_track+0x40/0x78 mm/kasan/common.c:78
 kasan_save_alloc_info+0x40/0x50 mm/kasan/generic.c:570
 poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
 __kasan_kmalloc+0x9c/0xb4 mm/kasan/common.c:415
 kasan_kmalloc include/linux/kasan.h:263 [inline]
 __do_kmalloc_node mm/slub.c:5414 [inline]
 __kmalloc_node_noprof+0x444/0x6e4 mm/slub.c:5426
 _kmalloc_array_node_noprof include/linux/slab.h:1297 [inline]
 blk_mq_alloc_tag_set+0x42c/0xb80 block/blk-mq.c:4894
 nbd_dev_add+0x29c/0x884 drivers/block/nbd.c:1975
 nbd_genl_connect+0x7f4/0x12b0 drivers/block/nbd.c:2223
 genl_family_rcv_msg_doit+0x1e4/0x2d4 net/netlink/genetlink.c:1114
 genl_family_rcv_msg net/netlink/genetlink.c:1194 [inline]
 genl_rcv_msg+0x43c/0x620 net/netlink/genetlink.c:1209
 netlink_rcv_skb+0x238/0x414 net/netlink/af_netlink.c:2575
 genl_rcv+0x38/0x50 net/netlink/genetlink.c:1218
 netlink_unicast_kernel net/netlink/af_netlink.c:1338 [inline]
 netlink_unicast+0x600/0x7f8 net/netlink/af_netlink.c:1364
 netlink_sendmsg+0x648/0x948 net/netlink/af_netlink.c:1919
 sock_sendmsg_nosec net/socket.c:800 [inline]
 __sock_sendmsg+0xc8/0x17c net/socket.c:815
 ____sys_sendmsg+0x3d0/0x6c8 net/socket.c:2713
 ___sys_sendmsg+0x198/0x224 net/socket.c:2767
 __sys_sendmsg+0x158/0x204 net/socket.c:2799
 __do_sys_sendmsg net/socket.c:2804 [inline]
 __se_sys_sendmsg net/socket.c:2802 [inline]
 __arm64_sys_sendmsg+0x88/0x9c net/socket.c:2802
 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
 invoke_syscall+0x98/0x244 arch/arm64/kernel/syscall.c:49
 el0_svc_common+0xec/0x23c arch/arm64/kernel/syscall.c:121
 do_el0_svc+0x4c/0x5c arch/arm64/kernel/syscall.c:140
 el0_svc+0x60/0x1d8 arch/arm64/kernel/entry-common.c:796
 el0t_64_sync_handler+0x44/0x104 arch/arm64/kernel/entry-common.c:815
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:606

The buggy address belongs to the object at ffff0000ed46a960
 which belongs to the cache kmalloc-8 of size 8
The buggy address is located 0 bytes to the right of
 allocated 8-byte region [ffff0000ed46a960, ffff0000ed46a968)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff0000ed46ac00 pfn:0x12d46a
flags: 0x5ffc00000000200(workingset|node=0|zone=2|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 05ffc00000000200 ffff0000c0001500 fffffdffc31599d0 ffff0000c0000348
raw: ffff0000ed46ac00 0000000000800070 00000000f5000000 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff0000ed46a800: 04 fc fc fc 00 fc fc fc fa fc fc fc 00 fc fc fc
 ffff0000ed46a880: 05 fc fc fc fa fc fc fc 00 fc fc fc fa fc fc fc
>ffff0000ed46a900: 06 fc fc fc 00 fc fc fc fa fc fc fc 00 fc fc fc
                                                          ^
 ffff0000ed46a980: 00 fc fc fc fa fc fc fc fa fc fc fc 00 fc fc fc
 ffff0000ed46aa00: fa fc fc fc 00 fc fc fc 00 fc fc fc fa fc fc fc
==================================================================
Unable to handle kernel paging request at virtual address 007c0003c0000001
Mem abort info:
  ESR = 0x0000000096000004
  EC = 0x25: DABT (current EL), IL = 32 bits
  SET = 0, FnV = 0
  EA = 0, S1PTW = 0
  FSC = 0x04: level 0 translation fault
Data abort info:
  ISV = 0, ISS = 0x00000004, ISS2 = 0x00000000
  CM = 0, WnR = 0, TnD = 0, TagAccess = 0
  GCS = 0, Overlay = 0, DirtyBit = 0
[007c0003c0000001] address between user and kernel address ranges
Internal error: Oops: 0000000096000004 [#1]  SMP
Modules linked in:
CPU: 0 UID: 0 PID: 11497 Comm: syz.0.1488 Tainted: G    B               syzkaller #0 PREEMPT 
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/14/2026
pstate: 83400005 (Nzcv daif +PAN -UAO +TCO +DIT -SSBS BTYPE=--)
pc : blk_mq_clear_rq_mapping block/blk-mq.c:3454 [inline]
pc : blk_mq_free_rqs+0x3a4/0x628 block/blk-mq.c:3492
lr : order_to_size block/blk-mq.c:3433 [inline]
lr : blk_mq_clear_rq_mapping block/blk-mq.c:3451 [inline]
lr : blk_mq_free_rqs+0x3a4/0x628 block/blk-mq.c:3492
sp : ffff800094826d40
x29: ffff800094826d70 x28: dfff800000000000 x27: 1fffe000196573d3
x26: 0000000000000000 x25: 0000000000000004 x24: fffffdffc6816828
x23: 007c8003c0000013 x22: fff1000040000000 x21: 0000000007816800
x20: 03e4001e0000000f x19: 007c8003c0000001 x18: 1fffe00035bd4c28
x17: 0000000000000003 x16: ffff800088a77000 x15: ffff800088b27780
x14: 000000000007184d x13: 0000000000000001 x12: 0000000000000003
x11: 0000000000000000 x10: 0000000000000001 x9 : 0000000000000000
x8 : 0000000000000000 x7 : 0000000000000000 x6 : ffff800081793b24
x5 : 0000000000000000 x4 : 0000000000000000 x3 : ffff80008178a730
x2 : 0000000000000000 x1 : ffff0001a0548000 x0 : 0000000000000000
dump_backtrace(regs = 00000000528e70b7 tsk = 0000000000000000)
Call trace:
 order_to_size block/blk-mq.c:3433 [inline] (P)
 blk_mq_clear_rq_mapping block/blk-mq.c:3451 [inline] (P)
 blk_mq_free_rqs+0x3a4/0x628 block/blk-mq.c:3492 (P)
 blk_mq_free_map_and_rqs+0x3c/0x64 block/blk-mq.c:4148
 blk_mq_free_sched_tags+0xb8/0x178 block/blk-mq-sched.c:425
 blk_mq_free_sched_res+0x64/0x114 block/blk-mq-sched.c:436
 elv_update_nr_hw_queues+0x150/0x210 block/elevator.c:722
 blk_mq_elv_switch_back block/blk-mq.c:5057 [inline]
 __blk_mq_update_nr_hw_queues block/blk-mq.c:5187 [inline]
 blk_mq_update_nr_hw_queues+0xd0c/0x11e0 block/blk-mq.c:5212
 nbd_start_device+0x15c/0xa44 drivers/block/nbd.c:1530
 nbd_genl_connect+0xde4/0x12b0 drivers/block/nbd.c:2310
 genl_family_rcv_msg_doit+0x1e4/0x2d4 net/netlink/genetlink.c:1114
 genl_family_rcv_msg net/netlink/genetlink.c:1194 [inline]
 genl_rcv_msg+0x43c/0x620 net/netlink/genetlink.c:1209
 netlink_rcv_skb+0x238/0x414 net/netlink/af_netlink.c:2575
 genl_rcv+0x38/0x50 net/netlink/genetlink.c:1218
 netlink_unicast_kernel net/netlink/af_netlink.c:1338 [inline]
 netlink_unicast+0x600/0x7f8 net/netlink/af_netlink.c:1364
 netlink_sendmsg+0x648/0x948 net/netlink/af_netlink.c:1919
 sock_sendmsg_nosec net/socket.c:800 [inline]
 __sock_sendmsg+0xc8/0x17c net/socket.c:815
 ____sys_sendmsg+0x3d0/0x6c8 net/socket.c:2713
 ___sys_sendmsg+0x198/0x224 net/socket.c:2767
 __sys_sendmsg+0x158/0x204 net/socket.c:2799
 __do_sys_sendmsg net/socket.c:2804 [inline]
 __se_sys_sendmsg net/socket.c:2802 [inline]
 __arm64_sys_sendmsg+0x88/0x9c net/socket.c:2802
 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
 invoke_syscall+0x98/0x244 arch/arm64/kernel/syscall.c:49
 el0_svc_common+0xec/0x23c arch/arm64/kernel/syscall.c:121
 do_el0_svc+0x4c/0x5c arch/arm64/kernel/syscall.c:140
 el0_svc+0x60/0x1d8 arch/arm64/kernel/entry-common.c:796
 el0t_64_sync_handler+0x44/0x104 arch/arm64/kernel/entry-common.c:815
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:606
Code: aa1a03e1 97bac670 b5000f1a 97bac5c7 (38fc6a68) 
---[ end trace 0000000000000000 ]---
----------------
Code disassembly (best guess):
   0:	aa1a03e1 	mov	x1, x26
   4:	97bac670 	bl	0xfffffffffeeb19c4
   8:	b5000f1a 	cbnz	x26, 0x1e8
   c:	97bac5c7 	bl	0xfffffffffeeb1728
* 10:	38fc6a68 	ldrsb	w8, [x19, x28] <-- trapping instruction