================================================================== BUG: KASAN: slab-use-after-free in xsk_bind+0x1582/0x16c0 net/xdp/xsk.c:1758 Read of size 4 at addr ffff88807e5b398c by task syz.0.800/9404 CPU: 0 UID: 0 PID: 9404 Comm: syz.0.800 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026 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/0x1c0 mm/kasan/report.c:595 xsk_bind+0x1582/0x16c0 net/xdp/xsk.c:1758 __sys_bind_socket net/socket.c:1920 [inline] __sys_bind_socket net/socket.c:1912 [inline] __sys_bind+0x1a9/0x260 net/socket.c:1951 __do_sys_bind net/socket.c:1956 [inline] __se_sys_bind net/socket.c:1954 [inline] __x64_sys_bind+0x72/0xb0 net/socket.c:1954 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f37f399e019 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:00007f37f48e5028 EFLAGS: 00000246 ORIG_RAX: 0000000000000031 RAX: ffffffffffffffda RBX: 00007f37f3c25fa0 RCX: 00007f37f399e019 RDX: 0000000000000010 RSI: 00002000000003c0 RDI: 0000000000000003 RBP: 00007f37f3a3500c R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f37f3c26038 R14: 00007f37f3c25fa0 R15: 00007ffc9cbcf328 Allocated by task 5607: 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] __kmalloc_cache_noprof+0x2e5/0x6c0 mm/slub.c:5489 _kmalloc_noprof include/linux/slab.h:988 [inline] _kzalloc_noprof include/linux/slab.h:1309 [inline] nsim_queue_alloc+0x3c/0x140 drivers/net/netdevsim/netdev.c:715 nsim_queue_init drivers/net/netdevsim/netdev.c:1012 [inline] nsim_init_netdevsim drivers/net/netdevsim/netdev.c:1059 [inline] nsim_create+0xb13/0x1420 drivers/net/netdevsim/netdev.c:1152 __nsim_dev_port_add+0x3ba/0x8f0 drivers/net/netdevsim/dev.c:1509 nsim_dev_port_add_all drivers/net/netdevsim/dev.c:1570 [inline] nsim_drv_probe+0xdbd/0x13a0 drivers/net/netdevsim/dev.c:1731 call_driver_probe drivers/base/dd.c:628 [inline] really_probe+0x241/0xa60 drivers/base/dd.c:706 __driver_probe_device+0x20e/0x450 drivers/base/dd.c:868 driver_probe_device+0x4a/0x140 drivers/base/dd.c:898 __device_attach_driver+0x1df/0x320 drivers/base/dd.c:1026 bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:500 __device_attach+0x1e4/0x4d0 drivers/base/dd.c:1098 device_initial_probe+0xaf/0xd0 drivers/base/dd.c:1153 bus_probe_device+0x64/0x160 drivers/base/bus.c:620 device_add+0x121d/0x1970 drivers/base/core.c:3772 nsim_bus_dev_new drivers/net/netdevsim/bus.c:471 [inline] new_device_store+0x40b/0x700 drivers/net/netdevsim/bus.c:191 bus_attr_store+0x74/0xb0 drivers/base/bus.c:172 sysfs_kf_write+0xf2/0x150 fs/sysfs/file.c:145 kernfs_fop_write_iter+0x3e0/0x5f0 fs/kernfs/file.c:345 new_sync_write fs/read_write.c:595 [inline] vfs_write+0x6ac/0x1050 fs/read_write.c:687 ksys_write+0x12a/0x250 fs/read_write.c:739 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 9400: 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:2677 [inline] slab_free mm/slub.c:6377 [inline] kfree+0x22b/0x6c0 mm/slub.c:6692 nsim_queue_mem_free+0xfe/0x190 drivers/net/netdevsim/netdev.c:796 netdev_rx_queue_reconfig+0x405/0x630 net/core/netdev_rx_queue.c:144 netdev_rx_queue_restart+0x8f/0xc0 net/core/netdev_rx_queue.c:183 nsim_qreset_write+0x2e3/0x410 drivers/net/netdevsim/netdev.c:887 full_proxy_write+0x135/0x1a0 fs/debugfs/file.c:388 vfs_write+0x2aa/0x1050 fs/read_write.c:685 ksys_write+0x12a/0x250 fs/read_write.c:739 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff88807e5b3800 which belongs to the cache kmalloc-cg-1k of size 1024 The buggy address is located 396 bytes inside of freed 1024-byte region [ffff88807e5b3800, ffff88807e5b3c00) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88807e5b0800 pfn:0x7e5b0 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 memcg:ffff888057716401 flags: 0xfff00000000240(workingset|head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000240 ffff88813fe2d280 ffffea000161b810 ffffea00009d8210 raw: ffff88807e5b0800 0000000800100009 00000000f5000000 ffff888057716401 head: 00fff00000000240 ffff88813fe2d280 ffffea000161b810 ffffea00009d8210 head: ffff88807e5b0800 0000000800100009 00000000f5000000 ffff888057716401 head: 00fff00000000003 fffffffffffffe01 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5609, tgid 5609 (syz-executor), ts 73097384659, free_ts 73097012359 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0xfd/0x120 mm/page_alloc.c:1859 prep_new_page mm/page_alloc.c:1867 [inline] get_page_from_freelist+0xf48/0x3530 mm/page_alloc.c:3946 __alloc_frozen_pages_noprof+0x299/0x2dc0 mm/page_alloc.c:5304 alloc_slab_page mm/slub.c:3266 [inline] allocate_slab mm/slub.c:3380 [inline] new_slab+0xa2/0x640 mm/slub.c:3426 refill_objects+0xe3/0x410 mm/slub.c:7310 refill_sheaf mm/slub.c:2804 [inline] __pcs_replace_empty_main+0x376/0x680 mm/slub.c:4675 alloc_from_pcs mm/slub.c:4773 [inline] slab_alloc_node mm/slub.c:4905 [inline] __do_kmalloc_node mm/slub.c:5333 [inline] __kmalloc_noprof+0x66d/0x820 mm/slub.c:5359 _kmalloc_noprof include/linux/slab.h:992 [inline] _kzalloc_noprof include/linux/slab.h:1309 [inline] __register_sysctl_table+0xac/0x1650 fs/proc/proc_sysctl.c:1378 neigh_sysctl_register+0x326/0x660 net/core/neighbour.c:3915 devinet_sysctl_register+0xb6/0x210 net/ipv4/devinet.c:2783 inetdev_init+0x2b8/0x570 net/ipv4/devinet.c:291 inetdev_event+0x7fa/0x17f0 net/ipv4/devinet.c:1590 notifier_call_chain+0x99/0x3f0 kernel/notifier.c:85 call_netdevice_notifiers_info+0xbe/0x110 net/core/dev.c:2250 call_netdevice_notifiers_extack net/core/dev.c:2288 [inline] call_netdevice_notifiers net/core/dev.c:2302 [inline] register_netdevice+0x1998/0x25a0 net/core/dev.c:11484 veth_newlink+0x44a/0xa00 drivers/net/veth.c:1892 page last free pid 5609 tgid 5609 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] __free_pages_prepare mm/page_alloc.c:1406 [inline] __free_frozen_pages+0x79f/0x1090 mm/page_alloc.c:2950 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x47/0xf0 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x1a0/0x1f0 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:350 kasan_slab_alloc include/linux/kasan.h:253 [inline] slab_post_alloc_hook mm/slub.c:4584 [inline] slab_alloc_node mm/slub.c:4917 [inline] __kmalloc_cache_noprof+0x265/0x6c0 mm/slub.c:5485 _kmalloc_noprof include/linux/slab.h:988 [inline] _kzalloc_noprof include/linux/slab.h:1309 [inline] ref_tracker_alloc+0x190/0x590 lib/ref_tracker.c:270 __netdev_tracker_alloc include/linux/netdevice.h:4499 [inline] netdev_hold include/linux/netdevice.h:4528 [inline] netdev_hold include/linux/netdevice.h:4523 [inline] netdev_queue_add_kobject net/core/net-sysfs.c:1973 [inline] netdev_queue_update_kobjects+0x2db/0x6f0 net/core/net-sysfs.c:2035 register_queue_kobjects net/core/net-sysfs.c:2098 [inline] netdev_register_kobject+0x2b3/0x3d0 net/core/net-sysfs.c:2341 register_netdevice+0x15b6/0x25a0 net/core/dev.c:11446 veth_newlink+0x44a/0xa00 drivers/net/veth.c:1892 rtnl_newlink_create net/core/rtnetlink.c:3913 [inline] __rtnl_newlink net/core/rtnetlink.c:4044 [inline] rtnl_newlink+0x1499/0x2380 net/core/rtnetlink.c:4159 rtnetlink_rcv_msg+0x95e/0xe90 net/core/rtnetlink.c:7076 netlink_rcv_skb+0x159/0x420 net/netlink/af_netlink.c:2556 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline] netlink_unicast+0x585/0x850 net/netlink/af_netlink.c:1345 netlink_sendmsg+0x8b0/0xda0 net/netlink/af_netlink.c:1900 sock_sendmsg_nosec net/socket.c:775 [inline] __sock_sendmsg net/socket.c:790 [inline] __sys_sendto+0x48b/0x4e0 net/socket.c:2252 Memory state around the buggy address: ffff88807e5b3880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807e5b3900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88807e5b3980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88807e5b3a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807e5b3a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================