================================================================== BUG: KASAN: slab-out-of-bounds in blk_mq_free_rqs+0x6e2/0x760 block/blk-mq.c:3526 Read of size 8 at addr ffff88804aa6dcf8 by task syz.5.8426/5808 CPU: 2 UID: 0 PID: 5808 Comm: syz.5.8426 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0x13d/0x4b0 mm/kasan/report.c:482 kasan_report+0xdf/0x1d0 mm/kasan/report.c:595 blk_mq_free_rqs+0x6e2/0x760 block/blk-mq.c:3526 blk_mq_alloc_rqs block/blk-mq.c:3707 [inline] blk_mq_alloc_map_and_rqs+0x9f9/0xeb0 block/blk-mq.c:4168 blk_mq_alloc_sched_tags+0x1de/0x350 block/blk-mq-sched.c:532 blk_mq_alloc_sched_res+0x8e/0x250 block/blk-mq-sched.c:555 blk_mq_alloc_sched_res_batch+0xfc/0x4f0 block/blk-mq-sched.c:593 __blk_mq_update_nr_hw_queues block/blk-mq.c:5181 [inline] blk_mq_update_nr_hw_queues+0x263/0x15f0 block/blk-mq.c:5260 nbd_start_device+0x1a6/0xbd0 drivers/block/nbd.c:1489 nbd_genl_connect+0xff2/0x1a40 drivers/block/nbd.c:2239 genl_family_rcv_msg_doit+0x214/0x300 net/netlink/genetlink.c:1114 genl_family_rcv_msg net/netlink/genetlink.c:1194 [inline] genl_rcv_msg+0x560/0x800 net/netlink/genetlink.c:1209 netlink_rcv_skb+0x159/0x420 net/netlink/af_netlink.c:2550 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1218 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x585/0x850 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x8b0/0xda0 net/netlink/af_netlink.c:1894 sock_sendmsg_nosec net/socket.c:787 [inline] __sock_sendmsg net/socket.c:802 [inline] ____sys_sendmsg+0x9e1/0xb70 net/socket.c:2698 ___sys_sendmsg+0x190/0x1e0 net/socket.c:2752 __sys_sendmsg+0x170/0x220 net/socket.c:2784 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline] __do_fast_syscall_32+0xe7/0x950 arch/x86/entry/syscall_32.c:307 do_fast_syscall_32+0x32/0x70 arch/x86/entry/syscall_32.c:332 entry_SYSENTER_compat_after_hwframe+0x84/0x8e RIP: 0023:0xf7f38f7c Code: d2 74 05 c1 e8 0c 89 02 8b 5d fc 31 c0 c9 c3 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1f 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 2e 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00 58 b8 RSP: 002b:00000000f53f650c EFLAGS: 00000292 ORIG_RAX: 0000000000000172 RAX: ffffffffffffffda RBX: 0000000000000006 RCX: 0000000080001ac0 RDX: 0000000000000004 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000292 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 Allocated by task 31205: kasan_save_stack+0x30/0x50 mm/kasan/common.c:57 kasan_save_track+0x14/0x30 mm/kasan/common.c:78 poison_kmalloc_redzone mm/kasan/common.c:398 [inline] __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:415 kasan_kmalloc include/linux/kasan.h:263 [inline] __do_kmalloc_node mm/slub.c:5295 [inline] __kmalloc_node_noprof+0x307/0x850 mm/slub.c:5301 kmalloc_node_noprof include/linux/slab.h:1081 [inline] __vmalloc_area_node mm/vmalloc.c:3857 [inline] __vmalloc_node_range_noprof+0x409/0x1630 mm/vmalloc.c:4064 __vmalloc_node_noprof+0xad/0xf0 mm/vmalloc.c:4124 xt_counters_alloc+0x4c/0x70 net/netfilter/x_tables.c:1474 __do_replace+0x97/0x990 net/ipv4/netfilter/arp_tables.c:906 compat_do_replace+0x31e/0x500 net/ipv4/netfilter/ip_tables.c:1529 do_ip6t_set_ctl+0x562/0xb00 net/ipv6/netfilter/ip6_tables.c:1641 nf_setsockopt+0x8d/0xf0 net/netfilter/nf_sockopt.c:101 ipv6_setsockopt+0x135/0x170 net/ipv6/ipv6_sockglue.c:970 tcp_setsockopt+0xa7/0x100 net/ipv4/tcp.c:4185 do_sock_setsockopt+0xf3/0x1d0 net/socket.c:2381 __sys_setsockopt+0x119/0x190 net/socket.c:2406 __do_compat_sys_socketcall net/compat.c:491 [inline] __se_compat_sys_socketcall net/compat.c:423 [inline] __ia32_compat_sys_socketcall+0x556/0x770 net/compat.c:423 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline] __do_fast_syscall_32+0xe7/0x950 arch/x86/entry/syscall_32.c:307 do_fast_syscall_32+0x32/0x70 arch/x86/entry/syscall_32.c:332 entry_SYSENTER_compat_after_hwframe+0x84/0x8e Freed by task 31205: kasan_save_stack+0x30/0x50 mm/kasan/common.c:57 kasan_save_track+0x14/0x30 mm/kasan/common.c:78 kasan_save_free_info+0x3b/0x70 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x5f/0x80 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2689 [inline] slab_free mm/slub.c:6250 [inline] kfree+0x223/0x6c0 mm/slub.c:6565 vfree mm/vmalloc.c:3475 [inline] vfree+0x286/0x8d0 mm/vmalloc.c:3436 __do_replace+0x78f/0x990 net/ipv4/netfilter/arp_tables.c:949 compat_do_replace+0x31e/0x500 net/ipv4/netfilter/ip_tables.c:1529 do_ip6t_set_ctl+0x562/0xb00 net/ipv6/netfilter/ip6_tables.c:1641 nf_setsockopt+0x8d/0xf0 net/netfilter/nf_sockopt.c:101 ipv6_setsockopt+0x135/0x170 net/ipv6/ipv6_sockglue.c:970 tcp_setsockopt+0xa7/0x100 net/ipv4/tcp.c:4185 do_sock_setsockopt+0xf3/0x1d0 net/socket.c:2381 __sys_setsockopt+0x119/0x190 net/socket.c:2406 __do_compat_sys_socketcall net/compat.c:491 [inline] __se_compat_sys_socketcall net/compat.c:423 [inline] __ia32_compat_sys_socketcall+0x556/0x770 net/compat.c:423 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline] __do_fast_syscall_32+0xe7/0x950 arch/x86/entry/syscall_32.c:307 do_fast_syscall_32+0x32/0x70 arch/x86/entry/syscall_32.c:332 entry_SYSENTER_compat_after_hwframe+0x84/0x8e The buggy address belongs to the object at ffff88804aa6dce0 which belongs to the cache kmalloc-8 of size 8 The buggy address is located 16 bytes to the right of allocated 8-byte region [ffff88804aa6dce0, ffff88804aa6dce8) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88804aa6dea0 pfn:0x4aa6d flags: 0x4fff00000000200(workingset|node=1|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 04fff00000000200 ffff88801b842500 ffffea0001c6c810 ffffea0001b14990 raw: ffff88804aa6dea0 0000000800800075 00000000f5000000 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0xd2cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 32071, tgid 32071 (syz-executor), ts 2137833296577, free_ts 2137833289125 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x153/0x170 mm/page_alloc.c:1858 prep_new_page mm/page_alloc.c:1866 [inline] get_page_from_freelist+0x11a6/0x33b0 mm/page_alloc.c:3946 __alloc_frozen_pages_noprof+0x27c/0x2bc0 mm/page_alloc.c:5226 alloc_slab_page mm/slub.c:3278 [inline] allocate_slab mm/slub.c:3467 [inline] new_slab+0xa6/0x6c0 mm/slub.c:3525 refill_objects+0x277/0x420 mm/slub.c:7271 refill_sheaf mm/slub.c:2816 [inline] __pcs_replace_empty_main+0x375/0x650 mm/slub.c:4651 alloc_from_pcs mm/slub.c:4749 [inline] slab_alloc_node mm/slub.c:4883 [inline] __do_kmalloc_node mm/slub.c:5294 [inline] __kmalloc_node_noprof+0x69a/0x850 mm/slub.c:5301 kmalloc_node_noprof include/linux/slab.h:1081 [inline] __vmalloc_area_node mm/vmalloc.c:3857 [inline] __vmalloc_node_range_noprof+0x409/0x1630 mm/vmalloc.c:4064 __vmalloc_node_noprof+0xad/0xf0 mm/vmalloc.c:4124 xt_compat_init_offsets+0xe2/0x1f0 net/netfilter/x_tables.c:779 compat_table_info+0xc5/0x640 net/ipv6/netfilter/ip6_tables.c:950 get_info+0x25c/0x5d0 net/ipv6/netfilter/ip6_tables.c:987 do_ip6t_get_ctl+0x169/0xa50 net/ipv6/netfilter/ip6_tables.c:1668 nf_getsockopt+0x7c/0xe0 net/netfilter/nf_sockopt.c:116 ipv6_getsockopt+0x207/0x2a0 net/ipv6/ipv6_sockglue.c:1464 tcp_getsockopt+0xa1/0x110 net/ipv4/tcp.c:4870 page last free pid 32071 tgid 32071 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] __free_pages_prepare mm/page_alloc.c:1402 [inline] __free_frozen_pages+0x747/0x1040 mm/page_alloc.c:2943 __kasan_populate_vmalloc_do mm/kasan/shadow.c:393 [inline] __kasan_populate_vmalloc+0x1ea/0x210 mm/kasan/shadow.c:424 kasan_populate_vmalloc include/linux/kasan.h:580 [inline] alloc_vmap_area+0x95d/0x2b70 mm/vmalloc.c:2123 __get_vm_area_node+0x1ca/0x330 mm/vmalloc.c:3226 __vmalloc_node_range_noprof+0x228/0x1630 mm/vmalloc.c:4024 __vmalloc_node_noprof+0xad/0xf0 mm/vmalloc.c:4124 xt_compat_init_offsets+0xe2/0x1f0 net/netfilter/x_tables.c:779 compat_table_info+0xc5/0x640 net/ipv6/netfilter/ip6_tables.c:950 get_info+0x25c/0x5d0 net/ipv6/netfilter/ip6_tables.c:987 do_ip6t_get_ctl+0x169/0xa50 net/ipv6/netfilter/ip6_tables.c:1668 nf_getsockopt+0x7c/0xe0 net/netfilter/nf_sockopt.c:116 ipv6_getsockopt+0x207/0x2a0 net/ipv6/ipv6_sockglue.c:1464 tcp_getsockopt+0xa1/0x110 net/ipv4/tcp.c:4870 do_sock_getsockopt+0x50a/0x6e0 net/socket.c:2487 __sys_getsockopt+0x133/0x1d0 net/socket.c:2518 __do_compat_sys_socketcall net/compat.c:494 [inline] __se_compat_sys_socketcall net/compat.c:423 [inline] __ia32_compat_sys_socketcall+0x6af/0x770 net/compat.c:423 Memory state around the buggy address: ffff88804aa6db80: fa fc fc fc fa fc fc fc fa fc fc fc fa fc fc fc ffff88804aa6dc00: fa fc fc fc fa fc fc fc 02 fc fc fc fa fc fc fc >ffff88804aa6dc80: fa fc fc fc fa fc fc fc 00 fc fc fc fa fc fc fc ^ ffff88804aa6dd00: 00 fc fc fc 05 fc fc fc fa fc fc fc fa fc fc fc ffff88804aa6dd80: fa fc fc fc fa fc fc fc fa fc fc fc fa fc fc fc ================================================================== ---------------- Code disassembly (best guess): 0: d2 74 05 c1 shlb %cl,-0x3f(%rbp,%rax,1) 4: e8 0c 89 02 8b call 0x8b028915 9: 5d pop %rbp a: fc cld b: 31 c0 xor %eax,%eax d: c9 leave e: c3 ret f: 90 nop 10: 90 nop 11: 90 nop 12: 90 nop 13: 90 nop 14: 90 nop 15: 90 nop 16: 90 nop 17: 90 nop 18: 90 nop 19: 90 nop 1a: 90 nop 1b: 90 nop 1c: 90 nop 1d: 90 nop 1e: 0f 1f 00 nopl (%rax) 21: 51 push %rcx 22: 52 push %rdx 23: 55 push %rbp 24: 89 e5 mov %esp,%ebp 26: 0f 34 sysenter 28: cd 80 int $0x80 * 2a: 5d pop %rbp <-- trapping instruction 2b: 5a pop %rdx 2c: 59 pop %rcx 2d: c3 ret 2e: 90 nop 2f: 2e 8d b4 26 00 00 00 cs lea 0x0(%rsi,%riz,1),%esi 36: 00 37: 8d b4 26 00 00 00 00 lea 0x0(%rsi,%riz,1),%esi 3e: 58 pop %rax 3f: b8 .byte 0xb8