================================================================== BUG: KASAN: slab-use-after-free in decode_session6+0x10e1/0x1950 net/xfrm/xfrm_policy.c:3460 Read of size 1 at addr ffff88802e364e04 by task syz-executor.5/12495 CPU: 0 PID: 12495 Comm: syz-executor.5 Not tainted 6.6.0-rc4-syzkaller-01096-g48533eca606e #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:1583 neigh_output include/net/neighbour.h:542 [inline] ip6_finish_output2+0x584/0x1700 net/ipv6/ip6_output.c:135 __ip6_finish_output net/ipv6/ip6_output.c:196 [inline] ip6_finish_output+0x485/0x1250 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] NF_HOOK include/linux/netfilter.h:304 [inline] rawv6_send_hdrinc net/ipv6/raw.c:655 [inline] rawv6_sendmsg+0x22ba/0x40a0 net/ipv6/raw.c:908 inet_sendmsg+0x9d/0xe0 net/ipv4/af_inet.c:840 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0xd5/0x180 net/socket.c:745 __sys_sendto+0x255/0x340 net/socket.c:2194 __do_sys_sendto net/socket.c:2206 [inline] __se_sys_sendto net/socket.c:2202 [inline] __x64_sys_sendto+0xe0/0x1b0 net/socket.c:2202 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: 0033:0x7f4f4ae7cae9 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:00007f4f499fe0c8 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00007f4f4af9bf80 RCX: 00007f4f4ae7cae9 RDX: 000000000000003f RSI: 0000000020000040 RDI: 0000000000000003 RBP: 00007f4f4aec847a R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007f4f4af9bf80 R15: 00007ffdb591ce18 Allocated by task 12183: kasan_save_stack+0x33/0x50 mm/kasan/common.c:45 kasan_set_track+0x25/0x30 mm/kasan/common.c:52 __kasan_slab_alloc+0x81/0x90 mm/kasan/common.c:328 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] kmem_cache_alloc_node+0x180/0x3f0 mm/slub.c:3523 kmalloc_reserve+0x166/0x260 net/core/skbuff.c:559 __alloc_skb+0x12b/0x330 net/core/skbuff.c:650 alloc_skb include/linux/skbuff.h:1286 [inline] alloc_uevent_skb+0x7d/0x210 lib/kobject_uevent.c:290 uevent_net_broadcast_untagged lib/kobject_uevent.c:326 [inline] kobject_uevent_net_broadcast lib/kobject_uevent.c:409 [inline] kobject_uevent_env+0xc20/0x1800 lib/kobject_uevent.c:593 nfs_netns_sysfs_setup+0x16f/0x1f0 fs/nfs/sysfs.c:202 nfs_net_init+0x15/0x20 fs/nfs/inode.c:2429 ops_init+0xb9/0x650 net/core/net_namespace.c:136 setup_net+0x422/0xa40 net/core/net_namespace.c:339 copy_net_ns+0x2fa/0x670 net/core/net_namespace.c:491 create_new_namespaces+0x3ea/0xb10 kernel/nsproxy.c:110 unshare_nsproxy_namespaces+0xc1/0x1f0 kernel/nsproxy.c:228 ksys_unshare+0x3da/0x930 kernel/fork.c:3435 __do_sys_unshare kernel/fork.c:3506 [inline] __se_sys_unshare kernel/fork.c:3504 [inline] __x64_sys_unshare+0x31/0x40 kernel/fork.c:3504 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 4495: 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+0xf0/0x480 mm/slub.c:3831 skb_kfree_head net/core/skbuff.c:947 [inline] skb_kfree_head net/core/skbuff.c:944 [inline] skb_free_head+0x17f/0x1b0 net/core/skbuff.c:961 skb_release_data+0x5ba/0x870 net/core/skbuff.c:991 skb_release_all net/core/skbuff.c:1057 [inline] __kfree_skb net/core/skbuff.c:1071 [inline] consume_skb net/core/skbuff.c:1287 [inline] consume_skb+0xd2/0x170 net/core/skbuff.c:1281 netlink_recvmsg+0x606/0xf20 net/netlink/af_netlink.c:1988 sock_recvmsg_nosec net/socket.c:1044 [inline] sock_recvmsg+0xe2/0x170 net/socket.c:1066 ____sys_recvmsg+0x21f/0x5c0 net/socket.c:2777 ___sys_recvmsg+0x115/0x1a0 net/socket.c:2819 __sys_recvmsg+0x114/0x1e0 net/socket.c:2849 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 The buggy address belongs to the object at ffff88802e364c00 which belongs to the cache skbuff_small_head of size 640 The buggy address is located 516 bytes inside of freed 640-byte region [ffff88802e364c00, ffff88802e364e80) The buggy address belongs to the physical page: page:ffffea0000b8d900 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2e364 head:ffffea0000b8d900 order:2 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000000840(slab|head|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000840 ffff888142e688c0 ffffea0001fa5e00 dead000000000002 raw: 0000000000000000 0000000000150015 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 2, migratetype Unmovable, gfp_mask 0x1d2820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 10758, tgid 10758 (syz-executor.0), ts 2069739162259, free_ts 2063825130037 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:2297 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+0x132/0x3f0 mm/slub.c:3523 kmalloc_reserve+0x166/0x260 net/core/skbuff.c:559 __alloc_skb+0x12b/0x330 net/core/skbuff.c:650 alloc_skb include/linux/skbuff.h:1286 [inline] nlmsg_new include/net/netlink.h:999 [inline] inet6_ifa_notify net/ipv6/addrconf.c:5546 [inline] __ipv6_ifa_notify+0x17b/0x11d0 net/ipv6/addrconf.c:6195 ipv6_ifa_notify net/ipv6/addrconf.c:6247 [inline] inet6_addr_add+0x722/0xbe0 net/ipv6/addrconf.c:3012 inet6_rtm_newaddr+0x11d5/0x1aa0 net/ipv6/addrconf.c:4975 rtnetlink_rcv_msg+0x3c4/0xdf0 net/core/rtnetlink.c:6480 netlink_rcv_skb+0x16b/0x440 net/netlink/af_netlink.c:2545 netlink_unicast_kernel net/netlink/af_netlink.c:1342 [inline] netlink_unicast+0x536/0x810 net/netlink/af_netlink.c:1368 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_kmalloc mm/kasan/common.c:340 [inline] __kasan_kmalloc+0x86/0xb0 mm/kasan/common.c:383 kasan_kmalloc include/linux/kasan.h:198 [inline] __do_kmalloc_node mm/slab_common.c:1023 [inline] __kmalloc_node_track_caller+0x61/0x100 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] alloc_skb_with_frags+0xe4/0x710 net/core/skbuff.c:6329 sock_alloc_send_pskb+0x7e4/0x970 net/core/sock.c:2788 unix_dgram_sendmsg+0x455/0x1c30 net/unix/af_unix.c:1953 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0xd5/0x180 net/socket.c:745 __sys_sendto+0x255/0x340 net/socket.c:2194 __do_sys_sendto net/socket.c:2206 [inline] __se_sys_sendto net/socket.c:2202 [inline] __x64_sys_sendto+0xe0/0x1b0 net/socket.c:2202 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80 Memory state around the buggy address: ffff88802e364d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88802e364d80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88802e364e00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88802e364e80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88802e364f00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================