================================================================== BUG: KASAN: use-after-free in instrument_atomic_read include/linux/instrumented.h:71 [inline] BUG: KASAN: use-after-free in atomic_read include/linux/atomic/atomic-instrumented.h:27 [inline] BUG: KASAN: use-after-free in ip6mr_sk_done+0x139/0x400 net/ipv6/ip6mr.c:1604 Read of size 4 at addr ffff888027326688 by task syz-executor.1/9175 CPU: 0 PID: 9175 Comm: syz-executor.1 Not tainted 6.0.0-syzkaller-02744-g2e30960097f6 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/22/2022 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:317 [inline] print_report.cold+0x2ba/0x719 mm/kasan/report.c:433 kasan_report+0xb1/0x1e0 mm/kasan/report.c:495 check_region_inline mm/kasan/generic.c:183 [inline] kasan_check_range+0x13d/0x180 mm/kasan/generic.c:189 instrument_atomic_read include/linux/instrumented.h:71 [inline] atomic_read include/linux/atomic/atomic-instrumented.h:27 [inline] ip6mr_sk_done+0x139/0x400 net/ipv6/ip6mr.c:1604 rawv6_close+0x58/0x80 net/ipv6/raw.c:1167 inet_release+0x12e/0x270 net/ipv4/af_inet.c:428 inet6_release+0x4c/0x70 net/ipv6/af_inet6.c:482 __sock_release net/socket.c:650 [inline] sock_release+0x87/0x1b0 net/socket.c:678 inet_ctl_sock_destroy include/net/inet_common.h:71 [inline] igmp6_net_exit+0x6b/0x170 net/ipv6/mcast.c:3167 ops_exit_list+0xb0/0x170 net/core/net_namespace.c:162 setup_net+0x7fb/0xc50 net/core/net_namespace.c:348 copy_net_ns+0x318/0x760 net/core/net_namespace.c:471 create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110 copy_namespaces+0x391/0x450 kernel/nsproxy.c:178 copy_process+0x304d/0x7090 kernel/fork.c:2257 kernel_clone+0xe7/0xab0 kernel/fork.c:2671 __do_sys_clone+0xba/0x100 kernel/fork.c:2805 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7fe713c8a5a9 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 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fe714e58118 EFLAGS: 00000206 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 00007fe713dabf80 RCX: 00007fe713c8a5a9 RDX: 0000000000000000 RSI: 0000000020000000 RDI: 0000000044088000 RBP: 00007fe713ce5580 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000200000c0 R11: 0000000000000206 R12: 0000000000000000 R13: 00007ffe333a971f R14: 00007fe714e58300 R15: 0000000000022000 Allocated by task 9175: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38 kasan_set_track mm/kasan/common.c:45 [inline] set_alloc_info mm/kasan/common.c:437 [inline] ____kasan_kmalloc mm/kasan/common.c:516 [inline] ____kasan_kmalloc mm/kasan/common.c:475 [inline] __kasan_kmalloc+0xa9/0xd0 mm/kasan/common.c:525 kmemdup+0x23/0x50 mm/util.c:129 kmemdup include/linux/fortify-string.h:565 [inline] addrconf_init_net+0x1be/0x870 net/ipv6/addrconf.c:7161 ops_init+0xaf/0x470 net/core/net_namespace.c:134 setup_net+0x5d1/0xc50 net/core/net_namespace.c:325 copy_net_ns+0x318/0x760 net/core/net_namespace.c:471 create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110 copy_namespaces+0x391/0x450 kernel/nsproxy.c:178 copy_process+0x304d/0x7090 kernel/fork.c:2257 kernel_clone+0xe7/0xab0 kernel/fork.c:2671 __do_sys_clone+0xba/0x100 kernel/fork.c:2805 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Freed by task 9175: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38 kasan_set_track+0x21/0x30 mm/kasan/common.c:45 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:370 ____kasan_slab_free mm/kasan/common.c:367 [inline] ____kasan_slab_free+0x166/0x1c0 mm/kasan/common.c:329 kasan_slab_free include/linux/kasan.h:200 [inline] slab_free_hook mm/slub.c:1759 [inline] slab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1785 slab_free mm/slub.c:3539 [inline] kfree+0xe2/0x580 mm/slub.c:4567 addrconf_init_net+0x649/0x870 net/ipv6/addrconf.c:7219 ops_init+0xaf/0x470 net/core/net_namespace.c:134 setup_net+0x5d1/0xc50 net/core/net_namespace.c:325 copy_net_ns+0x318/0x760 net/core/net_namespace.c:471 create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110 copy_namespaces+0x391/0x450 kernel/nsproxy.c:178 copy_process+0x304d/0x7090 kernel/fork.c:2257 kernel_clone+0xe7/0xab0 kernel/fork.c:2671 __do_sys_clone+0xba/0x100 kernel/fork.c:2805 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Last potentially related work creation: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38 __kasan_record_aux_stack+0xbe/0xd0 mm/kasan/generic.c:348 kvfree_call_rcu+0x74/0x8f0 kernel/rcu/tree.c:3341 br_multicast_destroy_mdb_entry+0x86/0xb0 net/bridge/br_multicast.c:609 br_multicast_gc.isra.0+0xca/0x110 net/bridge/br_multicast.c:775 br_multicast_gc_work+0xe5/0x130 net/bridge/br_multicast.c:3850 process_one_work+0x991/0x1610 kernel/workqueue.c:2289 worker_thread+0x665/0x1080 kernel/workqueue.c:2436 kthread+0x2e4/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 Second to last potentially related work creation: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38 __kasan_record_aux_stack+0xbe/0xd0 mm/kasan/generic.c:348 call_rcu+0x99/0x790 kernel/rcu/tree.c:2796 free_fib_info net/ipv4/fib_semantics.c:256 [inline] fib_create_info+0x220a/0x4ac0 net/ipv4/fib_semantics.c:1580 fib_table_insert+0x195/0x1be0 net/ipv4/fib_trie.c:1236 fib_magic+0x455/0x540 net/ipv4/fib_frontend.c:1098 fib_add_ifaddr+0x16b/0x540 net/ipv4/fib_frontend.c:1120 fib_netdev_event+0x462/0x680 net/ipv4/fib_frontend.c:1480 notifier_call_chain+0xb5/0x200 kernel/notifier.c:87 call_netdevice_notifiers_info+0xb5/0x130 net/core/dev.c:1945 call_netdevice_notifiers_extack net/core/dev.c:1983 [inline] call_netdevice_notifiers net/core/dev.c:1997 [inline] __dev_notify_flags+0x110/0x2b0 net/core/dev.c:8577 dev_change_flags+0x112/0x170 net/core/dev.c:8615 do_setlink+0x9f1/0x3bb0 net/core/rtnetlink.c:2788 __rtnl_newlink+0xd6a/0x17e0 net/core/rtnetlink.c:3547 rtnl_newlink+0x64/0xa0 net/core/rtnetlink.c:3594 rtnetlink_rcv_msg+0x43a/0xca0 net/core/rtnetlink.c:6091 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2540 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline] netlink_unicast+0x543/0x7f0 net/netlink/af_netlink.c:1345 netlink_sendmsg+0x917/0xe10 net/netlink/af_netlink.c:1921 sock_sendmsg_nosec net/socket.c:714 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:734 __sys_sendto+0x236/0x340 net/socket.c:2117 __do_sys_sendto net/socket.c:2129 [inline] __se_sys_sendto net/socket.c:2125 [inline] __x64_sys_sendto+0xdd/0x1b0 net/socket.c:2125 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd The buggy address belongs to the object at ffff888027326600 which belongs to the cache kmalloc-256 of size 256 The buggy address is located 136 bytes inside of 256-byte region [ffff888027326600, ffff888027326700) The buggy address belongs to the physical page: page:ffffea00009cc980 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x27326 head:ffffea00009cc980 order:1 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 ffffea0001e0ac00 dead000000000004 ffff888011841b40 raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000 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 3642, tgid 3642 (syz-executor.4), ts 134123689891, free_ts 35020652159 prep_new_page mm/page_alloc.c:2532 [inline] get_page_from_freelist+0x109b/0x2ce0 mm/page_alloc.c:4283 __alloc_pages+0x1c7/0x510 mm/page_alloc.c:5549 alloc_pages+0x1a6/0x270 mm/mempolicy.c:2270 alloc_slab_page mm/slub.c:1829 [inline] allocate_slab+0x27e/0x3d0 mm/slub.c:1974 new_slab mm/slub.c:2034 [inline] ___slab_alloc+0x84f/0xe80 mm/slub.c:3036 __slab_alloc.constprop.0+0x4d/0xa0 mm/slub.c:3123 slab_alloc_node mm/slub.c:3214 [inline] slab_alloc mm/slub.c:3256 [inline] __kmalloc+0x32b/0x340 mm/slub.c:4425 kmalloc include/linux/slab.h:605 [inline] kzalloc include/linux/slab.h:733 [inline] fib_create_info+0xdbe/0x4ac0 net/ipv4/fib_semantics.c:1449 fib_table_insert+0x195/0x1be0 net/ipv4/fib_trie.c:1236 fib_magic+0x455/0x540 net/ipv4/fib_frontend.c:1098 fib_add_ifaddr+0x16b/0x540 net/ipv4/fib_frontend.c:1120 fib_inetaddr_event+0x162/0x2a0 net/ipv4/fib_frontend.c:1434 notifier_call_chain+0xb5/0x200 kernel/notifier.c:87 blocking_notifier_call_chain kernel/notifier.c:382 [inline] blocking_notifier_call_chain+0x67/0x90 kernel/notifier.c:370 __inet_insert_ifa+0x919/0xbd0 net/ipv4/devinet.c:554 inet_rtm_newaddr+0x54d/0x980 net/ipv4/devinet.c:960 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1449 [inline] free_pcp_prepare+0x5e4/0xd20 mm/page_alloc.c:1499 free_unref_page_prepare mm/page_alloc.c:3380 [inline] free_unref_page+0x19/0x4d0 mm/page_alloc.c:3476 __folio_put_small mm/swap.c:105 [inline] __folio_put+0xc1/0x130 mm/swap.c:128 folio_put include/linux/mm.h:1125 [inline] put_page include/linux/mm.h:1177 [inline] anon_pipe_buf_release+0x3f7/0x4b0 fs/pipe.c:138 pipe_buf_release include/linux/pipe_fs_i.h:183 [inline] pipe_read+0x610/0x1100 fs/pipe.c:324 call_read_iter include/linux/fs.h:2181 [inline] new_sync_read fs/read_write.c:389 [inline] vfs_read+0x7f6/0x930 fs/read_write.c:470 ksys_read+0x1e8/0x250 fs/read_write.c:613 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Memory state around the buggy address: ffff888027326580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888027326600: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888027326680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888027326700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888027326780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================