================================================================== BUG: KASAN: slab-use-after-free in decode_session6+0x10e1/0x1950 net/xfrm/xfrm_policy.c:3460 Read of size 1 at addr ffff888076b8d6fe by task syz-executor.4/3317 CPU: 0 PID: 3317 Comm: syz-executor.4 Not tainted 6.6.0-rc2-syzkaller-00818-g93e7eca853ca #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/06/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:364 [inline] print_report+0xc4/0x620 mm/kasan/report.c:475 kasan_report+0xda/0x110 mm/kasan/report.c:588 decode_session6+0x10e1/0x1950 net/xfrm/xfrm_policy.c:3460 __xfrm_decode_session+0x54/0xb0 net/xfrm/xfrm_policy.c:3566 xfrm_decode_session_reverse include/net/xfrm.h:1223 [inline] icmpv6_route_lookup+0x397/0x550 net/ipv6/icmp.c:388 icmp6_send+0x123c/0x2740 net/ipv6/icmp.c:595 __icmpv6_send include/linux/icmpv6.h:28 [inline] icmpv6_send include/linux/icmpv6.h:49 [inline] ip6_link_failure+0x31/0x5a0 net/ipv6/route.c:2787 dst_link_failure include/net/dst.h:437 [inline] ip6_tnl_xmit+0x4f9/0x3920 net/ipv6/ip6_tunnel.c:1268 ipxip6_tnl_xmit net/ipv6/ip6_tunnel.c:1384 [inline] ip6_tnl_start_xmit+0x6ef/0x1750 net/ipv6/ip6_tunnel.c:1432 __netdev_start_xmit include/linux/netdevice.h:4911 [inline] netdev_start_xmit include/linux/netdevice.h:4925 [inline] xmit_one net/core/dev.c:3544 [inline] dev_hard_start_xmit+0x13d/0x6c0 net/core/dev.c:3560 sch_direct_xmit+0x1ac/0xc20 net/sched/sch_generic.c:342 qdisc_restart net/sched/sch_generic.c:407 [inline] __qdisc_run+0x540/0x19d0 net/sched/sch_generic.c:415 __dev_xmit_skb net/core/dev.c:3834 [inline] __dev_queue_xmit+0x24db/0x3d60 net/core/dev.c:4306 dev_queue_xmit include/linux/netdevice.h:3092 [inline] neigh_connected_output+0x42c/0x5d0 net/core/neighbour.c:1581 neigh_output include/net/neighbour.h:542 [inline] ip6_finish_output2+0x581/0x1700 net/ipv6/ip6_output.c:135 ip6_fragment+0x22c9/0x2a20 net/ipv6/ip6_output.c:946 __ip6_finish_output net/ipv6/ip6_output.c:194 [inline] ip6_finish_output+0x803/0x1250 net/ipv6/ip6_output.c:207 NF_HOOK_COND include/linux/netfilter.h:293 [inline] ip6_output+0x1e2/0x530 net/ipv6/ip6_output.c:228 dst_output include/net/dst.h:458 [inline] ip6_local_out+0xaf/0x190 net/ipv6/output_core.c:155 ip6_send_skb+0xb7/0x330 net/ipv6/ip6_output.c:2017 udp_v6_send_skb+0x9a6/0x1910 net/ipv6/udp.c:1284 udpv6_sendmsg+0x2482/0x2f00 net/ipv6/udp.c:1578 inet6_sendmsg+0x9d/0xe0 net/ipv6/af_inet6.c:656 sock_sendmsg_nosec net/socket.c:730 [inline] sock_sendmsg+0xd9/0x180 net/socket.c:753 ____sys_sendmsg+0x2ac/0x940 net/socket.c:2541 ___sys_sendmsg+0x135/0x1d0 net/socket.c:2595 __sys_sendmmsg+0x1a1/0x450 net/socket.c:2681 __do_sys_sendmmsg net/socket.c:2710 [inline] __se_sys_sendmmsg net/socket.c:2707 [inline] __x64_sys_sendmmsg+0x9c/0x100 net/socket.c:2707 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f26cc87cae9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 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 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f26cd5fa0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000133 RAX: ffffffffffffffda RBX: 00007f26cc99bf80 RCX: 00007f26cc87cae9 RDX: 0000000000000001 RSI: 0000000020008180 RDI: 0000000000000003 RBP: 00007f26cc8c847a R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007f26cc99bf80 R15: 00007fffc29a41d8 Allocated by task 3308: kasan_save_stack+0x33/0x50 mm/kasan/common.c:45 kasan_set_track+0x25/0x30 mm/kasan/common.c:52 ____kasan_kmalloc mm/kasan/common.c:374 [inline] __kasan_kmalloc+0xa2/0xb0 mm/kasan/common.c:383 kasan_kmalloc include/linux/kasan.h:198 [inline] __do_kmalloc_node mm/slab_common.c:1023 [inline] __kmalloc+0x60/0x100 mm/slab_common.c:1036 kmalloc include/linux/slab.h:603 [inline] sk_prot_alloc+0x1a4/0x2a0 net/core/sock.c:2083 sk_alloc+0x3a/0x7f0 net/core/sock.c:2136 __netlink_create+0x63/0x380 net/netlink/af_netlink.c:647 netlink_create+0x3dc/0x670 net/netlink/af_netlink.c:712 __sock_create+0x328/0x800 net/socket.c:1552 sock_create net/socket.c:1603 [inline] __sys_socket_create net/socket.c:1640 [inline] __sys_socket+0x14c/0x260 net/socket.c:1691 __do_sys_socket net/socket.c:1705 [inline] __se_sys_socket net/socket.c:1703 [inline] __x64_sys_socket+0x72/0xb0 net/socket.c:1703 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Freed by task 16: kasan_save_stack+0x33/0x50 mm/kasan/common.c:45 kasan_set_track+0x25/0x30 mm/kasan/common.c:52 kasan_save_free_info+0x2b/0x40 mm/kasan/generic.c:522 ____kasan_slab_free mm/kasan/common.c:236 [inline] ____kasan_slab_free+0x15b/0x1b0 mm/kasan/common.c:200 kasan_slab_free include/linux/kasan.h:164 [inline] slab_free_hook mm/slub.c:1800 [inline] slab_free_freelist_hook+0x114/0x1e0 mm/slub.c:1826 slab_free mm/slub.c:3809 [inline] __kmem_cache_free+0xb8/0x2f0 mm/slub.c:3822 sk_prot_free net/core/sock.c:2119 [inline] __sk_destruct+0x5fc/0x770 net/core/sock.c:2211 sk_destruct+0xc2/0xf0 net/core/sock.c:2226 __sk_free+0xc4/0x3a0 net/core/sock.c:2237 sk_free+0x7c/0xa0 net/core/sock.c:2248 deferred_put_nlk_sk+0x155/0x2f0 net/netlink/af_netlink.c:748 rcu_do_batch kernel/rcu/tree.c:2139 [inline] rcu_core+0x805/0x1bb0 kernel/rcu/tree.c:2403 __do_softirq+0x218/0x965 kernel/softirq.c:553 Last potentially related work creation: kasan_save_stack+0x33/0x50 mm/kasan/common.c:45 __kasan_record_aux_stack+0xbc/0xd0 mm/kasan/generic.c:492 __call_rcu_common.constprop.0+0x9a/0x790 kernel/rcu/tree.c:2653 netlink_release+0xe44/0x1f90 net/netlink/af_netlink.c:831 __sock_release+0xae/0x260 net/socket.c:659 sock_close+0x1c/0x20 net/socket.c:1402 __fput+0x3f7/0xa70 fs/file_table.c:384 task_work_run+0x14d/0x240 kernel/task_work.c:179 exit_task_work include/linux/task_work.h:38 [inline] do_exit+0xa92/0x2a20 kernel/exit.c:874 do_group_exit+0xd4/0x2a0 kernel/exit.c:1024 get_signal+0x23ba/0x2790 kernel/signal.c:2892 arch_do_signal_or_restart+0x90/0x7f0 arch/x86/kernel/signal.c:309 exit_to_user_mode_loop kernel/entry/common.c:168 [inline] exit_to_user_mode_prepare+0x11f/0x240 kernel/entry/common.c:204 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline] syscall_exit_to_user_mode+0x1d/0x60 kernel/entry/common.c:296 do_syscall_64+0x44/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x63/0xcd Second to last potentially related work creation: kasan_save_stack+0x33/0x50 mm/kasan/common.c:45 __kasan_record_aux_stack+0xbc/0xd0 mm/kasan/generic.c:492 __call_rcu_common.constprop.0+0x9a/0x790 kernel/rcu/tree.c:2653 netlink_release+0xe44/0x1f90 net/netlink/af_netlink.c:831 __sock_release+0xae/0x260 net/socket.c:659 sock_close+0x1c/0x20 net/socket.c:1402 __fput+0x3f7/0xa70 fs/file_table.c:384 task_work_run+0x14d/0x240 kernel/task_work.c:179 get_signal+0x106f/0x2790 kernel/signal.c:2668 arch_do_signal_or_restart+0x90/0x7f0 arch/x86/kernel/signal.c:309 exit_to_user_mode_loop kernel/entry/common.c:168 [inline] exit_to_user_mode_prepare+0x11f/0x240 kernel/entry/common.c:204 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline] syscall_exit_to_user_mode+0x1d/0x60 kernel/entry/common.c:296 do_syscall_64+0x44/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x63/0xcd The buggy address belongs to the object at ffff888076b8d000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 1790 bytes inside of freed 2048-byte region [ffff888076b8d000, ffff888076b8d800) The buggy address belongs to the physical page: page:ffffea0001dae200 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x76b88 head:ffffea0001dae200 order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000000840(slab|head|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000840 ffff888012c42000 dead000000000100 dead000000000122 raw: 0000000000000000 0000000080080008 00000001ffffffff 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 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 17946, tgid 17940 (syz-executor.2), ts 1663719950895, free_ts 1663695056569 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x2cf/0x340 mm/page_alloc.c:1536 prep_new_page mm/page_alloc.c:1543 [inline] get_page_from_freelist+0xee0/0x2f20 mm/page_alloc.c:3170 __alloc_pages+0x1d0/0x4a0 mm/page_alloc.c:4426 alloc_pages+0x1a9/0x270 mm/mempolicy.c:2298 alloc_slab_page mm/slub.c:1870 [inline] allocate_slab+0x251/0x380 mm/slub.c:2017 new_slab mm/slub.c:2070 [inline] ___slab_alloc+0x8c7/0x1580 mm/slub.c:3223 __slab_alloc.constprop.0+0x56/0xa0 mm/slub.c:3322 __slab_alloc_node mm/slub.c:3375 [inline] slab_alloc_node mm/slub.c:3468 [inline] __kmem_cache_alloc_node+0x131/0x340 mm/slub.c:3517 __do_kmalloc_node mm/slab_common.c:1022 [inline] __kmalloc_node_track_caller+0x50/0x100 mm/slab_common.c:1043 kmalloc_reserve+0xef/0x260 net/core/skbuff.c:581 __alloc_skb+0x12b/0x330 net/core/skbuff.c:650 alloc_skb include/linux/skbuff.h:1286 [inline] _sctp_make_chunk+0x51/0x260 net/sctp/sm_make_chunk.c:1443 sctp_make_data net/sctp/sm_make_chunk.c:1475 [inline] sctp_make_datafrag_empty+0x16d/0x230 net/sctp/sm_make_chunk.c:740 sctp_datamsg_from_user+0x591/0x12c0 net/sctp/chunk.c:262 sctp_sendmsg_to_asoc+0xadb/0x1a90 net/sctp/socket.c:1858 sctp_sendmsg+0xee4/0x1e80 net/sctp/socket.c:2030 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1136 [inline] free_unref_page_prepare+0x476/0xa40 mm/page_alloc.c:2312 free_unref_page+0x33/0x3b0 mm/page_alloc.c:2405 __unfreeze_partials+0x21d/0x240 mm/slub.c:2655 qlink_free mm/kasan/quarantine.c:166 [inline] qlist_free_all+0x6a/0x170 mm/kasan/quarantine.c:185 kasan_quarantine_reduce+0x18e/0x1d0 mm/kasan/quarantine.c:292 __kasan_slab_alloc+0x65/0x90 mm/kasan/common.c:305 kasan_slab_alloc include/linux/kasan.h:188 [inline] slab_post_alloc_hook mm/slab.h:762 [inline] slab_alloc_node mm/slub.c:3478 [inline] slab_alloc mm/slub.c:3486 [inline] __kmem_cache_alloc_lru mm/slub.c:3493 [inline] kmem_cache_alloc+0x16c/0x3b0 mm/slub.c:3502 vma_lock_alloc kernel/fork.c:459 [inline] vm_area_dup+0x53/0x2f0 kernel/fork.c:512 __split_vma+0x181/0x1070 mm/mmap.c:2342 do_vmi_align_munmap+0x360/0x15f0 mm/mmap.c:2477 do_vmi_munmap+0x20e/0x450 mm/mmap.c:2623 mmap_region+0x184/0x28b0 mm/mmap.c:2673 do_mmap+0x893/0xef0 mm/mmap.c:1354 vm_mmap_pgoff+0x1a8/0x3b0 mm/util.c:546 ksys_mmap_pgoff+0x422/0x5b0 mm/mmap.c:1400 __do_sys_mmap arch/x86/kernel/sys_x86_64.c:93 [inline] __se_sys_mmap arch/x86/kernel/sys_x86_64.c:86 [inline] __x64_sys_mmap+0x125/0x190 arch/x86/kernel/sys_x86_64.c:86 Memory state around the buggy address: ffff888076b8d580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888076b8d600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888076b8d680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888076b8d700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888076b8d780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================