================================================================== BUG: KASAN: slab-use-after-free in ipvlan_get_iflink+0x73/0x80 drivers/net/ipvlan/ipvlan_main.c:353 Read of size 4 at addr ffff88803434c0e0 by task kworker/u8:2/35 CPU: 0 UID: 0 PID: 35 Comm: kworker/u8:2 Not tainted 6.13.0-rc1-next-20241205-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: events_unbound linkwatch_event Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0x169/0x550 mm/kasan/report.c:489 kasan_report+0x143/0x180 mm/kasan/report.c:602 ipvlan_get_iflink+0x73/0x80 drivers/net/ipvlan/ipvlan_main.c:353 default_operstate net/core/link_watch.c:45 [inline] rfc2863_policy+0x174/0x300 net/core/link_watch.c:67 linkwatch_do_dev+0x3e/0x170 net/core/link_watch.c:170 __linkwatch_run_queue+0x44f/0x6c0 net/core/link_watch.c:234 linkwatch_event+0x4c/0x60 net/core/link_watch.c:277 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Allocated by task 10305: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:260 [inline] __do_kmalloc_node mm/slub.c:4283 [inline] __kmalloc_node_noprof+0x290/0x4d0 mm/slub.c:4289 __kvmalloc_node_noprof+0x72/0x190 mm/util.c:650 alloc_netdev_mqs+0xa4/0x1080 net/core/dev.c:11209 rtnl_create_link+0x2f9/0xc20 net/core/rtnetlink.c:3595 rtnl_newlink_create+0x210/0xa40 net/core/rtnetlink.c:3771 __rtnl_newlink net/core/rtnetlink.c:3896 [inline] rtnl_newlink+0x1b40/0x20e0 net/core/rtnetlink.c:4009 rtnetlink_rcv_msg+0x791/0xcf0 net/core/rtnetlink.c:6919 netlink_rcv_skb+0x1e3/0x430 net/netlink/af_netlink.c:2542 netlink_unicast_kernel net/netlink/af_netlink.c:1321 [inline] netlink_unicast+0x7f6/0x990 net/netlink/af_netlink.c:1347 netlink_sendmsg+0x8e4/0xcb0 net/netlink/af_netlink.c:1891 sock_sendmsg_nosec net/socket.c:711 [inline] __sock_sendmsg+0x221/0x270 net/socket.c:726 __sys_sendto+0x363/0x4c0 net/socket.c:2197 __do_sys_sendto net/socket.c:2204 [inline] __se_sys_sendto net/socket.c:2200 [inline] __x64_sys_sendto+0xde/0x100 net/socket.c:2200 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 10718: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:576 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x59/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2338 [inline] slab_free mm/slub.c:4598 [inline] kfree+0x196/0x430 mm/slub.c:4746 device_release+0x99/0x1c0 kobject_cleanup lib/kobject.c:689 [inline] kobject_release lib/kobject.c:720 [inline] kref_put include/linux/kref.h:65 [inline] kobject_put+0x22f/0x480 lib/kobject.c:737 netdev_run_todo+0xe79/0x1000 net/core/dev.c:10924 rtnl_unlock net/core/rtnetlink.c:152 [inline] rtnl_net_unlock include/linux/rtnetlink.h:133 [inline] rtnl_dellink+0x760/0x8d0 net/core/rtnetlink.c:3526 rtnetlink_rcv_msg+0x791/0xcf0 net/core/rtnetlink.c:6919 netlink_rcv_skb+0x1e3/0x430 net/netlink/af_netlink.c:2542 netlink_unicast_kernel net/netlink/af_netlink.c:1321 [inline] netlink_unicast+0x7f6/0x990 net/netlink/af_netlink.c:1347 netlink_sendmsg+0x8e4/0xcb0 net/netlink/af_netlink.c:1891 sock_sendmsg_nosec net/socket.c:711 [inline] __sock_sendmsg+0x221/0x270 net/socket.c:726 ____sys_sendmsg+0x52a/0x7e0 net/socket.c:2583 ___sys_sendmsg net/socket.c:2637 [inline] __sys_sendmsg+0x269/0x350 net/socket.c:2669 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff88803434c000 which belongs to the cache kmalloc-cg-4k of size 4096 The buggy address is located 224 bytes inside of freed 4096-byte region [ffff88803434c000, ffff88803434d000) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x34348 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 memcg:ffff888032b99b81 flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000040 ffff88801ac4f500 ffffea00017f1e00 dead000000000002 raw: 0000000000000000 0000000000040004 00000000f5000000 ffff888032b99b81 head: 00fff00000000040 ffff88801ac4f500 ffffea00017f1e00 dead000000000002 head: 0000000000000000 0000000000040004 00000000f5000000 ffff888032b99b81 head: 00fff00000000003 ffffea0000d0d201 ffffffffffffffff 0000000000000000 head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000 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 6356, tgid 6356 (syz-executor), ts 132513411783, free_ts 132041985137 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1f4/0x240 mm/page_alloc.c:1549 prep_new_page mm/page_alloc.c:1557 [inline] get_page_from_freelist+0x365c/0x37a0 mm/page_alloc.c:3475 __alloc_frozen_pages_noprof+0x292/0x710 mm/page_alloc.c:4752 alloc_pages_mpol+0x30e/0x550 mm/mempolicy.c:2270 alloc_slab_page mm/slub.c:2408 [inline] allocate_slab+0x8f/0x3a0 mm/slub.c:2574 new_slab mm/slub.c:2627 [inline] ___slab_alloc+0xc27/0x14a0 mm/slub.c:3815 __slab_alloc+0x58/0xa0 mm/slub.c:3905 __slab_alloc_node mm/slub.c:3980 [inline] slab_alloc_node mm/slub.c:4141 [inline] __do_kmalloc_node mm/slub.c:4282 [inline] __kmalloc_node_track_caller_noprof+0x2e9/0x4c0 mm/slub.c:4302 kmemdup_noprof+0x2a/0x60 mm/util.c:135 __addrconf_sysctl_register+0xb1/0x3a0 net/ipv6/addrconf.c:7221 addrconf_sysctl_register+0x167/0x1c0 net/ipv6/addrconf.c:7287 ipv6_add_dev+0xcf6/0x1220 net/ipv6/addrconf.c:456 addrconf_notify+0x6a7/0x1020 net/ipv6/addrconf.c:3674 notifier_call_chain+0x1a5/0x3f0 kernel/notifier.c:85 call_netdevice_notifiers_extack net/core/dev.c:2034 [inline] call_netdevice_notifiers net/core/dev.c:2048 [inline] register_netdevice+0x167f/0x1b00 net/core/dev.c:10632 tun_set_iff+0x85c/0xe80 drivers/net/tun.c:2862 page last free pid 6355 tgid 6355 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1127 [inline] free_frozen_pages+0xe0d/0x10e0 mm/page_alloc.c:2658 discard_slab mm/slub.c:2673 [inline] __put_partials+0x160/0x1c0 mm/slub.c:3142 put_cpu_partial+0x17c/0x250 mm/slub.c:3217 __slab_free+0x290/0x380 mm/slub.c:4468 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x9a/0x140 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x14f/0x170 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x23/0x80 mm/kasan/common.c:329 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4104 [inline] slab_alloc_node mm/slub.c:4153 [inline] kmem_cache_alloc_noprof+0x1d9/0x380 mm/slub.c:4160 new_handle fs/jbd2/transaction.c:461 [inline] jbd2__journal_start+0x14d/0x5d0 fs/jbd2/transaction.c:488 __ext4_journal_start_sb+0x239/0x600 fs/ext4/ext4_jbd2.c:112 __ext4_journal_start fs/ext4/ext4_jbd2.h:326 [inline] ext4_dirty_inode+0x92/0x110 fs/ext4/inode.c:6039 __mark_inode_dirty+0x2ee/0xe90 fs/fs-writeback.c:2515 generic_update_time fs/inode.c:2112 [inline] inode_update_time fs/inode.c:2125 [inline] __file_update_time fs/inode.c:2353 [inline] file_update_time+0x3d2/0x450 fs/inode.c:2383 ext4_page_mkwrite+0x213/0x1100 fs/ext4/inode.c:6160 do_page_mkwrite+0x15c/0x350 mm/memory.c:3245 do_shared_fault mm/memory.c:5469 [inline] do_fault mm/memory.c:5531 [inline] do_pte_missing mm/memory.c:4048 [inline] handle_pte_fault+0x10c6/0x5ee0 mm/memory.c:5872 Memory state around the buggy address: ffff88803434bf80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88803434c000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88803434c080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88803434c100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88803434c180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================