block nbd0: Receive control failed (result -32) block nbd0: shutting down sockets ================================================================== BUG: KASAN: slab-use-after-free in instrument_atomic_read_write include/linux/instrumented.h:96 [inline] BUG: KASAN: slab-use-after-free in atomic_dec include/linux/atomic/atomic-instrumented.h:592 [inline] BUG: KASAN: slab-use-after-free in recv_work+0x1b3b/0x1c30 drivers/block/nbd.c:1028 Write of size 4 at addr ffff88803110c878 by task kworker/u9:2/5857 CPU: 0 UID: 0 PID: 5857 Comm: kworker/u9:2 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 Workqueue: nbd0-recv recv_work Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xca/0x240 mm/kasan/report.c:482 kasan_report+0x118/0x150 mm/kasan/report.c:595 check_region_inline mm/kasan/generic.c:-1 [inline] kasan_check_range+0x2b0/0x2c0 mm/kasan/generic.c:200 instrument_atomic_read_write include/linux/instrumented.h:96 [inline] atomic_dec include/linux/atomic/atomic-instrumented.h:592 [inline] recv_work+0x1b3b/0x1c30 drivers/block/nbd.c:1028 process_one_work kernel/workqueue.c:3263 [inline] process_scheduled_works+0xae1/0x1790 kernel/workqueue.c:3346 worker_thread+0xa57/0xfc0 kernel/workqueue.c:3427 kthread+0x711/0x890 kernel/kthread.c:463 ret_from_fork+0x4b8/0x860 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Allocated by task 6457: kasan_save_stack mm/kasan/common.c:56 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:77 poison_kmalloc_redzone mm/kasan/common.c:400 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:417 kasan_kmalloc include/linux/kasan.h:262 [inline] __kmalloc_cache_noprof+0x3d5/0x6f0 mm/slub.c:5763 kmalloc_noprof include/linux/slab.h:957 [inline] kzalloc_noprof include/linux/slab.h:1094 [inline] nbd_alloc_and_init_config+0x88/0x260 drivers/block/nbd.c:1683 nbd_genl_connect+0x9d7/0x18f0 drivers/block/nbd.c:2145 genl_family_rcv_msg_doit+0x215/0x300 net/netlink/genetlink.c:1115 genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline] genl_rcv_msg+0x60e/0x790 net/netlink/genetlink.c:1210 netlink_rcv_skb+0x208/0x470 net/netlink/af_netlink.c:2552 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline] netlink_unicast+0x82f/0x9e0 net/netlink/af_netlink.c:1346 netlink_sendmsg+0x812/0xb30 net/netlink/af_netlink.c:1896 sock_sendmsg_nosec net/socket.c:727 [inline] __sock_sendmsg+0x21c/0x270 net/socket.c:742 ____sys_sendmsg+0x530/0x860 net/socket.c:2630 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2684 __sys_sendmsg net/socket.c:2716 [inline] __do_sys_sendmsg net/socket.c:2721 [inline] __se_sys_sendmsg net/socket.c:2719 [inline] __x64_sys_sendmsg+0x19b/0x260 net/socket.c:2719 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x8a/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x76/0x7e Freed by task 5857: kasan_save_stack mm/kasan/common.c:56 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:77 __kasan_save_free_info+0x46/0x50 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+0x5c/0x80 mm/kasan/common.c:284 kasan_slab_free include/linux/kasan.h:234 [inline] slab_free_hook mm/slub.c:2539 [inline] slab_free mm/slub.c:6630 [inline] kfree+0x19a/0x6d0 mm/slub.c:6837 nbd_config_put+0x642/0x790 drivers/block/nbd.c:1463 recv_work+0x1b25/0x1c30 drivers/block/nbd.c:1027 process_one_work kernel/workqueue.c:3263 [inline] process_scheduled_works+0xae1/0x1790 kernel/workqueue.c:3346 worker_thread+0xa57/0xfc0 kernel/workqueue.c:3427 kthread+0x711/0x890 kernel/kthread.c:463 ret_from_fork+0x4b8/0x860 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 The buggy address belongs to the object at ffff88803110c800 which belongs to the cache kmalloc-256 of size 256 The buggy address is located 120 bytes inside of freed 256-byte region [ffff88803110c800, ffff88803110c900) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x3110c head: order:1 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 ksm flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000040 ffff88813fe26b40 ffffea0001decf00 dead000000000003 raw: 0000000000000000 0000000080100010 00000000f5000000 0000000000000000 head: 00fff00000000040 ffff88813fe26b40 ffffea0001decf00 dead000000000003 head: 0000000000000000 0000000080100010 00000000f5000000 0000000000000000 head: 00fff00000000001 ffffea0000c44301 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000002 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 1, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5898, tgid 5898 (syz-executor), ts 89000560912, free_ts 88282633462 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1850 prep_new_page mm/page_alloc.c:1858 [inline] get_page_from_freelist+0x2cf4/0x2ea0 mm/page_alloc.c:3884 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5183 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2416 alloc_slab_page mm/slub.c:3055 [inline] allocate_slab+0x96/0x340 mm/slub.c:3228 new_slab mm/slub.c:3282 [inline] ___slab_alloc+0xecf/0x18d0 mm/slub.c:4651 __slab_alloc+0x65/0x100 mm/slub.c:4770 __slab_alloc_node mm/slub.c:4846 [inline] slab_alloc_node mm/slub.c:5268 [inline] __kmalloc_cache_noprof+0x411/0x6f0 mm/slub.c:5758 kmalloc_noprof include/linux/slab.h:957 [inline] kzalloc_noprof include/linux/slab.h:1094 [inline] ____ip_mc_inc_group+0x528/0xde0 net/ipv4/igmp.c:1535 __ip_mc_inc_group net/ipv4/igmp.c:1573 [inline] ip_mc_inc_group net/ipv4/igmp.c:1579 [inline] ip_mc_up+0x125/0x300 net/ipv4/igmp.c:1880 inetdev_event+0xfb3/0x15b0 net/ipv4/devinet.c:1630 notifier_call_chain+0x1b6/0x3d0 kernel/notifier.c:85 call_netdevice_notifiers_extack net/core/dev.c:2267 [inline] call_netdevice_notifiers net/core/dev.c:2281 [inline] __dev_notify_flags+0x18d/0x2e0 net/core/dev.c:-1 netif_change_flags+0xe8/0x1a0 net/core/dev.c:9705 do_setlink+0xe40/0x41b0 net/core/rtnetlink.c:3151 rtnl_changelink net/core/rtnetlink.c:3769 [inline] __rtnl_newlink net/core/rtnetlink.c:3928 [inline] rtnl_newlink+0x1619/0x1c80 net/core/rtnetlink.c:4065 page last free pid 5838 tgid 5838 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1394 [inline] __free_frozen_pages+0xbc2/0xd30 mm/page_alloc.c:2906 __slab_free+0x2e7/0x390 mm/slub.c:5962 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x97/0x140 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:352 kasan_slab_alloc include/linux/kasan.h:252 [inline] slab_post_alloc_hook mm/slub.c:4970 [inline] slab_alloc_node mm/slub.c:5280 [inline] kmem_cache_alloc_noprof+0x367/0x6e0 mm/slub.c:5287 getname_flags+0xb8/0x540 fs/namei.c:146 getname include/linux/fs.h:2922 [inline] __do_sys_unlink fs/namei.c:4783 [inline] __se_sys_unlink fs/namei.c:4781 [inline] __x64_sys_unlink+0x3a/0x50 fs/namei.c:4781 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x8a/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x76/0x7e Memory state around the buggy address: ffff88803110c700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88803110c780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88803110c800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88803110c880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88803110c900: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================