================================================================== BUG: KASAN: use-after-free in ax25_addr_ax25dev+0x55/0x160 net/ax25/ax25_dev.c:38 Read of size 8 at addr ffff88802228ae08 by task syz.4.2043/14094 CPU: 0 PID: 14094 Comm: syz.4.2043 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Call Trace: dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106 print_address_description+0x60/0x2d0 mm/kasan/report.c:248 __kasan_report mm/kasan/report.c:434 [inline] kasan_report+0xdf/0x130 mm/kasan/report.c:451 ax25_addr_ax25dev+0x55/0x160 net/ax25/ax25_dev.c:38 ax25_fwd_ioctl+0x1c/0x4b0 net/ax25/ax25_dev.c:148 ax25_ioctl+0x8fe/0xb70 net/ax25/af_ax25.c:1889 sock_do_ioctl+0xd3/0x2f0 net/socket.c:1140 sock_ioctl+0x4ed/0x6e0 net/socket.c:1257 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl+0xfa/0x170 fs/ioctl.c:860 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f7123135be9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f712135b038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f712335d180 RCX: 00007f7123135be9 RDX: 0000200000000040 RSI: 00000000000089ea RDI: 0000000000000007 RBP: 00007f71231b8e19 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f712335d218 R14: 00007f712335d180 R15: 00007ffd38f11b38 Allocated by task 10447: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track mm/kasan/common.c:46 [inline] set_alloc_info mm/kasan/common.c:434 [inline] ____kasan_kmalloc mm/kasan/common.c:513 [inline] __kasan_kmalloc+0xb5/0xf0 mm/kasan/common.c:522 kmalloc include/linux/slab.h:604 [inline] kzalloc include/linux/slab.h:735 [inline] push_stack+0x90/0x510 kernel/bpf/verifier.c:1047 check_cond_jmp_op kernel/bpf/verifier.c:9358 [inline] do_check+0xc414/0xeac0 kernel/bpf/verifier.c:11489 do_check_common+0xe67/0x16c0 kernel/bpf/verifier.c:13502 do_check_main kernel/bpf/verifier.c:13565 [inline] bpf_check+0x31f3/0xf090 kernel/bpf/verifier.c:14136 bpf_prog_load+0x1043/0x1550 kernel/bpf/syscall.c:2348 __sys_bpf+0x4c2/0x670 kernel/bpf/syscall.c:4651 __do_sys_bpf kernel/bpf/syscall.c:4755 [inline] __se_sys_bpf kernel/bpf/syscall.c:4753 [inline] __x64_sys_bpf+0x78/0x90 kernel/bpf/syscall.c:4753 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 Last potentially related work creation: kasan_save_stack+0x35/0x60 mm/kasan/common.c:38 kasan_record_aux_stack+0xb8/0x100 mm/kasan/generic.c:348 insert_work+0x54/0x3d0 kernel/workqueue.c:1366 __queue_work+0x9c5/0xd50 kernel/workqueue.c:1532 queue_work_on+0x11d/0x1d0 kernel/workqueue.c:1559 inetaddr_event+0xe0/0x140 drivers/infiniband/core/roce_gid_mgmt.c:869 notifier_call_chain kernel/notifier.c:83 [inline] blocking_notifier_call_chain+0x103/0x1b0 kernel/notifier.c:318 __inet_insert_ifa+0x9e9/0xbc0 net/ipv4/devinet.c:568 inet_rtm_newaddr+0x940/0x1800 net/ipv4/devinet.c:967 rtnetlink_rcv_msg+0x9b9/0xe60 net/core/rtnetlink.c:5650 netlink_rcv_skb+0x1e0/0x430 net/netlink/af_netlink.c:2507 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x774/0x920 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x8ab/0xbc0 net/netlink/af_netlink.c:1918 sock_sendmsg_nosec net/socket.c:704 [inline] __sock_sendmsg net/socket.c:716 [inline] __sys_sendto+0x423/0x580 net/socket.c:2063 __do_sys_sendto net/socket.c:2075 [inline] __se_sys_sendto net/socket.c:2071 [inline] __x64_sys_sendto+0xda/0xf0 net/socket.c:2071 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 Second to last potentially related work creation: kasan_save_stack+0x35/0x60 mm/kasan/common.c:38 kasan_record_aux_stack+0xb8/0x100 mm/kasan/generic.c:348 __call_rcu kernel/rcu/tree.c:3011 [inline] call_rcu+0x182/0x930 kernel/rcu/tree.c:3091 inetdev_destroy net/ipv4/devinet.c:327 [inline] inetdev_event+0x771/0x1360 net/ipv4/devinet.c:1612 notifier_call_chain kernel/notifier.c:83 [inline] raw_notifier_call_chain+0xcb/0x160 kernel/notifier.c:391 call_netdevice_notifiers_extack net/core/dev.c:2061 [inline] call_netdevice_notifiers net/core/dev.c:2075 [inline] unregister_netdevice_many+0xf57/0x18f0 net/core/dev.c:11134 unregister_netdevice_queue+0x31c/0x360 net/core/dev.c:11067 unregister_netdevice include/linux/netdevice.h:3020 [inline] nsim_destroy+0x49/0x150 drivers/net/netdevsim/netdev.c:382 __nsim_dev_port_del+0x155/0x1c0 drivers/net/netdevsim/dev.c:1349 nsim_dev_port_del_all drivers/net/netdevsim/dev.c:1362 [inline] nsim_dev_reload_destroy+0x16c/0x240 drivers/net/netdevsim/dev.c:1561 nsim_dev_remove+0x59/0x100 drivers/net/netdevsim/dev.c:1577 __device_release_driver drivers/base/dd.c:1227 [inline] device_release_driver_internal+0x475/0x750 drivers/base/dd.c:1262 bus_remove_device+0x2e2/0x400 drivers/base/bus.c:531 device_del+0x628/0xa70 drivers/base/core.c:3600 device_unregister+0x1c/0xc0 drivers/base/core.c:3633 nsim_bus_dev_del drivers/net/netdevsim/bus.c:454 [inline] del_device_store+0x27d/0x380 drivers/net/netdevsim/bus.c:354 kernfs_fop_write_iter+0x379/0x4c0 fs/kernfs/file.c:296 call_write_iter include/linux/fs.h:2172 [inline] new_sync_write fs/read_write.c:507 [inline] vfs_write+0x712/0xd00 fs/read_write.c:594 ksys_write+0x14d/0x250 fs/read_write.c:647 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 The buggy address belongs to the object at ffff88802228ae00 which belongs to the cache kmalloc-192 of size 192 The buggy address is located 8 bytes inside of 192-byte region [ffff88802228ae00, ffff88802228aec0) The buggy address belongs to the page: page:ffffea000088a280 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88802228ac00 pfn:0x2228a flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000200 ffffea00007f66c8 ffffea00007f2fc8 ffff888016841a00 raw: ffff88802228ac00 000000000010000d 00000001ffffffff 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 0x12cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY), pid 1, ts 7400950747, free_ts 6467277170 prep_new_page mm/page_alloc.c:2426 [inline] get_page_from_freelist+0x1b77/0x1c60 mm/page_alloc.c:4192 __alloc_pages+0x1e1/0x470 mm/page_alloc.c:5487 alloc_page_interleave+0x24/0x1e0 mm/mempolicy.c:2031 alloc_slab_page mm/slub.c:1775 [inline] allocate_slab mm/slub.c:1912 [inline] new_slab+0xc0/0x4b0 mm/slub.c:1975 ___slab_alloc+0x81e/0xdf0 mm/slub.c:3008 __slab_alloc mm/slub.c:3095 [inline] slab_alloc_node mm/slub.c:3186 [inline] slab_alloc mm/slub.c:3228 [inline] kmem_cache_alloc_trace+0x1a5/0x2a0 mm/slub.c:3245 kmalloc include/linux/slab.h:604 [inline] kzalloc include/linux/slab.h:735 [inline] mon_bus_init+0x50/0x290 drivers/usb/mon/mon_main.c:287 mon_bus_add drivers/usb/mon/mon_main.c:199 [inline] mon_notify+0x10e/0x3e0 drivers/usb/mon/mon_main.c:230 notifier_call_chain kernel/notifier.c:83 [inline] blocking_notifier_call_chain+0x103/0x1b0 kernel/notifier.c:318 usb_register_bus+0xcf/0x140 drivers/usb/core/hcd.c:935 usb_add_hcd+0x356/0xef0 drivers/usb/core/hcd.c:2893 dummy_hcd_probe+0x130/0x260 drivers/usb/gadget/udc/dummy_hcd.c:2675 platform_probe+0x137/0x1c0 drivers/base/platform.c:1391 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x284/0xc80 drivers/base/dd.c:595 __driver_probe_device+0x18c/0x330 drivers/base/dd.c:755 driver_probe_device+0x4f/0x420 drivers/base/dd.c:785 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1340 [inline] free_pcp_prepare mm/page_alloc.c:1391 [inline] free_unref_page_prepare+0x637/0x6c0 mm/page_alloc.c:3317 free_unref_page+0x94/0x280 mm/page_alloc.c:3396 mm_free_pgd kernel/fork.c:653 [inline] __mmdrop+0xaa/0x3e0 kernel/fork.c:704 free_bprm+0x141/0x300 fs/exec.c:1494 kernel_execve+0x380/0x900 fs/exec.c:2015 call_usermodehelper_exec_async+0x207/0x350 kernel/umh.c:112 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 Memory state around the buggy address: ffff88802228ad00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88802228ad80: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc >ffff88802228ae00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88802228ae80: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff88802228af00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 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