================================================================== BUG: KASAN: slab-out-of-bounds in decode_session6+0x10e1/0x1950 net/xfrm/xfrm_policy.c:3460 Read of size 1 at addr ffff888049d22eba by task syz-executor.1/3524 CPU: 1 PID: 3524 Comm: syz-executor.1 Not tainted 6.5.0-rc4-syzkaller-00174-gc1a515d3c027 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2023 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+0x11c1/0x2720 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:2785 dst_link_failure include/net/dst.h:437 [inline] ip6_tnl_xmit+0x4f9/0x3960 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:4910 [inline] netdev_start_xmit include/linux/netdevice.h:4924 [inline] xmit_one net/core/dev.c:3537 [inline] dev_hard_start_xmit+0x13d/0x6c0 net/core/dev.c:3553 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:3827 [inline] __dev_queue_xmit+0x26ab/0x3f20 net/core/dev.c:4169 dev_queue_xmit include/linux/netdevice.h:3088 [inline] neigh_connected_output+0x42c/0x5d0 net/core/neighbour.c:1581 neigh_output include/net/neighbour.h:544 [inline] ip6_finish_output2+0x5d0/0x1b20 net/ipv6/ip6_output.c:135 __ip6_finish_output net/ipv6/ip6_output.c:196 [inline] ip6_finish_output+0x485/0x11d0 net/ipv6/ip6_output.c:207 NF_HOOK_COND include/linux/netfilter.h:292 [inline] ip6_output+0x243/0x890 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:2008 udp_v6_send_skb+0x9b2/0x1900 net/ipv6/udp.c:1302 udpv6_sendmsg+0x24bf/0x2f80 net/ipv6/udp.c:1596 inet6_sendmsg+0x9d/0xe0 net/ipv6/af_inet6.c:651 sock_sendmsg_nosec net/socket.c:725 [inline] sock_sendmsg+0xd9/0x180 net/socket.c:748 ____sys_sendmsg+0x2ac/0x940 net/socket.c:2494 ___sys_sendmsg+0x135/0x1d0 net/socket.c:2548 __sys_sendmmsg+0x2a5/0x450 net/socket.c:2627 __compat_sys_sendmmsg net/compat.c:360 [inline] __do_compat_sys_sendmmsg net/compat.c:367 [inline] __se_compat_sys_sendmmsg net/compat.c:364 [inline] __ia32_compat_sys_sendmmsg+0x9d/0x100 net/compat.c:364 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline] __do_fast_syscall_32+0x61/0xe0 arch/x86/entry/common.c:178 do_fast_syscall_32+0x33/0x70 arch/x86/entry/common.c:203 entry_SYSENTER_compat_after_hwframe+0x70/0x82 RIP: 0023:0xf7f0b579 Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00 RSP: 002b:00000000f7f065ac EFLAGS: 00000292 ORIG_RAX: 0000000000000159 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000020000340 RDX: 0000000000000001 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000292 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 Allocated by task 3192: 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 kmalloc include/linux/slab.h:582 [inline] kzalloc include/linux/slab.h:703 [inline] nexthop_net_init+0x73/0x140 net/ipv4/nexthop.c:3754 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:3438 __do_sys_unshare kernel/fork.c:3509 [inline] __se_sys_unshare kernel/fork.c:3507 [inline] __ia32_sys_unshare+0x30/0x40 kernel/fork.c:3507 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline] __do_fast_syscall_32+0x61/0xe0 arch/x86/entry/common.c:178 do_fast_syscall_32+0x33/0x70 arch/x86/entry/common.c:203 entry_SYSENTER_compat_after_hwframe+0x70/0x82 Freed by task 29351: 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+0x15e/0x1b0 mm/kasan/common.c:200 kasan_slab_free include/linux/kasan.h:162 [inline] slab_free_hook mm/slub.c:1792 [inline] slab_free_freelist_hook+0x10b/0x1e0 mm/slub.c:1818 slab_free mm/slub.c:3801 [inline] __kmem_cache_free+0xb8/0x2f0 mm/slub.c:3814 nexthop_net_exit_batch+0x1f9/0x280 net/ipv4/nexthop.c:3744 ops_exit_list+0x125/0x170 net/core/net_namespace.c:175 cleanup_net+0x505/0xb20 net/core/net_namespace.c:614 process_one_work+0xaa2/0x16f0 kernel/workqueue.c:2597 worker_thread+0x687/0x1110 kernel/workqueue.c:2748 kthread+0x33a/0x430 kernel/kthread.c:389 ret_from_fork+0x2c/0x70 arch/x86/kernel/process.c:145 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304 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:2649 netlink_release+0xea3/0x1f80 net/netlink/af_netlink.c:828 __sock_release+0xcd/0x290 net/socket.c:654 sock_close+0x1c/0x20 net/socket.c:1386 __fput+0x3fd/0xac0 fs/file_table.c:384 task_work_run+0x14d/0x240 kernel/task_work.c:179 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop kernel/entry/common.c:171 [inline] exit_to_user_mode_prepare+0x210/0x240 kernel/entry/common.c:204 __syscall_exit_to_user_mode_work kernel/entry/common.c:286 [inline] syscall_exit_to_user_mode+0x1d/0x50 kernel/entry/common.c:297 __do_fast_syscall_32+0x6d/0xe0 arch/x86/entry/common.c:181 do_fast_syscall_32+0x33/0x70 arch/x86/entry/common.c:203 entry_SYSENTER_compat_after_hwframe+0x70/0x82 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 insert_work+0x4a/0x330 kernel/workqueue.c:1553 __queue_work+0x5f5/0x1040 kernel/workqueue.c:1714 queue_work_on+0xed/0x110 kernel/workqueue.c:1744 queue_work include/linux/workqueue.h:506 [inline] afs_queue_server_manager fs/afs/server.c:612 [inline] afs_purge_servers+0xee/0x350 fs/afs/server.c:626 afs_net_exit+0x87/0xf0 fs/afs/main.c:157 ops_exit_list+0xb0/0x170 net/core/net_namespace.c:170 cleanup_net+0x505/0xb20 net/core/net_namespace.c:614 process_one_work+0xaa2/0x16f0 kernel/workqueue.c:2597 worker_thread+0x687/0x1110 kernel/workqueue.c:2748 kthread+0x33a/0x430 kernel/kthread.c:389 ret_from_fork+0x2c/0x70 arch/x86/kernel/process.c:145 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304 The buggy address belongs to the object at ffff888049d22000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 1722 bytes to the right of allocated 2048-byte region [ffff888049d22000, ffff888049d22800) The buggy address belongs to the physical page: page:ffffea0001274800 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x49d20 head:ffffea0001274800 order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0 anon flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000010200 ffff888012842000 0000000000000000 dead000000000001 raw: 0000000000000000 0000000000080008 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 0xd28c0(GFP_NOWAIT|__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5068, tgid 5068 (syz-executor.1), ts 112159868947, free_ts 14976602178 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x2d2/0x350 mm/page_alloc.c:1570 prep_new_page mm/page_alloc.c:1577 [inline] get_page_from_freelist+0x10a9/0x31e0 mm/page_alloc.c:3221 __alloc_pages+0x1d0/0x4a0 mm/page_alloc.c:4477 alloc_pages+0x1a9/0x270 mm/mempolicy.c:2292 alloc_slab_page mm/slub.c:1862 [inline] allocate_slab+0x24e/0x380 mm/slub.c:2009 new_slab mm/slub.c:2062 [inline] ___slab_alloc+0x8bc/0x1570 mm/slub.c:3215 __slab_alloc.constprop.0+0x56/0xa0 mm/slub.c:3314 __slab_alloc_node mm/slub.c:3367 [inline] slab_alloc_node mm/slub.c:3460 [inline] __kmem_cache_alloc_node+0x137/0x350 mm/slub.c:3509 __do_kmalloc_node mm/slab_common.c:984 [inline] __kmalloc_node_track_caller+0x4d/0x100 mm/slab_common.c:1005 kmalloc_reserve+0xef/0x270 net/core/skbuff.c:575 pskb_expand_head+0x236/0x1170 net/core/skbuff.c:2042 netlink_trim+0x1eb/0x240 net/netlink/af_netlink.c:1321 netlink_broadcast+0xb5/0xea0 net/netlink/af_netlink.c:1517 nlmsg_multicast include/net/netlink.h:1083 [inline] nlmsg_notify+0x99/0x210 net/netlink/af_netlink.c:2592 rtnl_notify net/core/rtnetlink.c:771 [inline] rtmsg_ifinfo_send net/core/rtnetlink.c:4045 [inline] rtmsg_ifinfo_event net/core/rtnetlink.c:4061 [inline] rtmsg_ifinfo_event net/core/rtnetlink.c:4048 [inline] rtnetlink_event+0x16e/0x1f0 net/core/rtnetlink.c:6479 notifier_call_chain+0xb6/0x3b0 kernel/notifier.c:93 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1161 [inline] free_unref_page_prepare+0x508/0xb90 mm/page_alloc.c:2348 free_unref_page+0x33/0x3b0 mm/page_alloc.c:2443 free_contig_range+0xb6/0x190 mm/page_alloc.c:6395 destroy_args+0x686/0x940 mm/debug_vm_pgtable.c:1029 debug_vm_pgtable+0x2339/0x3ff0 mm/debug_vm_pgtable.c:1410 do_one_initcall+0x117/0x630 init/main.c:1232 do_initcall_level init/main.c:1294 [inline] do_initcalls init/main.c:1310 [inline] do_basic_setup init/main.c:1329 [inline] kernel_init_freeable+0x5bd/0x8f0 init/main.c:1546 kernel_init+0x1c/0x2a0 init/main.c:1437 ret_from_fork+0x2c/0x70 arch/x86/kernel/process.c:145 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304 Memory state around the buggy address: ffff888049d22d80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888049d22e00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff888049d22e80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff888049d22f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888049d22f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ================================================================== ---------------- Code disassembly (best guess), 2 bytes skipped: 0: 10 06 adc %al,(%rsi) 2: 03 74 b4 01 add 0x1(%rsp,%rsi,4),%esi 6: 10 07 adc %al,(%rdi) 8: 03 74 b0 01 add 0x1(%rax,%rsi,4),%esi c: 10 08 adc %cl,(%rax) e: 03 74 d8 01 add 0x1(%rax,%rbx,8),%esi 1e: 00 51 52 add %dl,0x52(%rcx) 21: 55 push %rbp 22: 89 e5 mov %esp,%ebp 24: 0f 34 sysenter 26: cd 80 int $0x80 * 28: 5d pop %rbp <-- trapping instruction 29: 5a pop %rdx 2a: 59 pop %rcx 2b: c3 ret 2c: 90 nop 2d: 90 nop 2e: 90 nop 2f: 90 nop 30: 8d b4 26 00 00 00 00 lea 0x0(%rsi,%riz,1),%esi 37: 8d b4 26 00 00 00 00 lea 0x0(%rsi,%riz,1),%esi