================================================================== BUG: KASAN: slab-out-of-bounds in decode_session6+0x10e1/0x1950 net/xfrm/xfrm_policy.c:3460 Read of size 1 at addr ffff88807546d1c7 by task syz-executor.5/2415 CPU: 0 PID: 2415 Comm: syz-executor.5 Not tainted 6.5.0-rc6-syzkaller-00117-g0e8860d2125f #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023 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] NF_HOOK include/linux/netfilter.h:303 [inline] NF_HOOK include/linux/netfilter.h:297 [inline] ip6_xmit+0xe1d/0x1fe0 net/ipv6/ip6_output.c:344 inet6_csk_xmit+0x3c0/0x730 net/ipv6/inet6_connection_sock.c:135 __tcp_transmit_skb+0x199b/0x3a80 net/ipv4/tcp_output.c:1401 tcp_transmit_skb net/ipv4/tcp_output.c:1419 [inline] tcp_send_syn_data net/ipv4/tcp_output.c:3888 [inline] tcp_connect+0x21c6/0x5730 net/ipv4/tcp_output.c:3953 tcp_v6_connect+0x1476/0x1fb0 net/ipv6/tcp_ipv6.c:338 __inet_stream_connect+0x947/0xe10 net/ipv4/af_inet.c:666 tcp_sendmsg_fastopen+0x3ce/0x710 net/ipv4/tcp.c:1019 tcp_sendmsg_locked+0x1e5f/0x3420 net/ipv4/tcp.c:1070 tcp_sendmsg+0x2e/0x40 net/ipv4/tcp.c:1333 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_sendto+0x255/0x340 net/socket.c:2134 __do_sys_sendto net/socket.c:2146 [inline] __se_sys_sendto net/socket.c:2142 [inline] __ia32_sys_sendto+0xdd/0x1b0 net/socket.c:2142 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: 0023:0xf7fd5579 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:00000000f7fd05ac EFLAGS: 00000292 ORIG_RAX: 0000000000000171 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00000000200000c0 RDX: 0000000000000001 RSI: 0000000020008845 RDI: 0000000020b63fe4 RBP: 000000000000001b R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000292 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 Allocated by task 4479: 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:186 [inline] slab_post_alloc_hook mm/slab.h:762 [inline] slab_alloc_node mm/slub.c:3470 [inline] kmem_cache_alloc_node+0x185/0x3f0 mm/slub.c:3515 kmalloc_reserve+0x167/0x270 net/core/skbuff.c:559 __alloc_skb+0x12b/0x330 net/core/skbuff.c:644 alloc_skb include/linux/skbuff.h:1289 [inline] netlink_alloc_large_skb net/netlink/af_netlink.c:1211 [inline] netlink_sendmsg+0x9c6/0xe30 net/netlink/af_netlink.c:1889 sock_sendmsg_nosec net/socket.c:725 [inline] sock_sendmsg+0xd9/0x180 net/socket.c:748 ____sys_sendmsg+0x6ac/0x940 net/socket.c:2494 ___sys_sendmsg+0x135/0x1d0 net/socket.c:2548 __sys_sendmsg+0x117/0x1e0 net/socket.c:2577 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 ffff88807546cf00 which belongs to the cache skbuff_small_head of size 640 The buggy address is located 71 bytes to the right of allocated 640-byte region [ffff88807546cf00, ffff88807546d180) The buggy address belongs to the physical page: page:ffffea0001d51b00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7546c head:ffffea0001d51b00 order:2 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 ffff888141e5d780 0000000000000000 dead000000000001 raw: 0000000000000000 0000000080150015 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 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 32379, tgid 32378 (syz-executor.5), ts 1717086990250, free_ts 1618376848616 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+0x137/0x3f0 mm/slub.c:3515 kmalloc_reserve+0x167/0x270 net/core/skbuff.c:559 __alloc_skb+0x12b/0x330 net/core/skbuff.c:644 alloc_skb include/linux/skbuff.h:1289 [inline] nlmsg_new include/net/netlink.h:1003 [inline] mpls_netconf_notify_devconf+0x4a/0x110 net/mpls/af_mpls.c:1189 mpls_dev_sysctl_unregister net/mpls/af_mpls.c:1449 [inline] mpls_dev_notify+0x609/0xa00 net/mpls/af_mpls.c:1658 notifier_call_chain+0xb6/0x3b0 kernel/notifier.c:93 call_netdevice_notifiers_info+0xb9/0x130 net/core/dev.c:1962 call_netdevice_notifiers_extack net/core/dev.c:2000 [inline] call_netdevice_notifiers net/core/dev.c:2014 [inline] unregister_netdevice_many_notify+0x82b/0x19a0 net/core/dev.c:10850 unregister_netdevice_many net/core/dev.c:10906 [inline] default_device_exit_batch+0x584/0x740 net/core/dev.c:11359 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 __unfreeze_partials+0x21d/0x240 mm/slub.c:2647 qlink_free mm/kasan/quarantine.c:166 [inline] qlist_free_all+0x6a/0x170 mm/kasan/quarantine.c:185 kasan_quarantine_reduce+0x18b/0x1d0 mm/kasan/quarantine.c:292 __kasan_slab_alloc+0x65/0x90 mm/kasan/common.c:305 kasan_slab_alloc include/linux/kasan.h:186 [inline] slab_post_alloc_hook mm/slab.h:762 [inline] slab_alloc_node mm/slub.c:3470 [inline] kmem_cache_alloc_node+0x185/0x3f0 mm/slub.c:3515 __alloc_skb+0x287/0x330 net/core/skbuff.c:634 alloc_skb include/linux/skbuff.h:1289 [inline] netlink_alloc_large_skb net/netlink/af_netlink.c:1211 [inline] netlink_sendmsg+0x9c6/0xe30 net/netlink/af_netlink.c:1889 sock_sendmsg_nosec net/socket.c:725 [inline] sock_sendmsg+0xd9/0x180 net/socket.c:748 ____sys_sendmsg+0x6ac/0x940 net/socket.c:2494 ___sys_sendmsg+0x135/0x1d0 net/socket.c:2548 __sys_sendmsg+0x117/0x1e0 net/socket.c:2577 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 Memory state around the buggy address: ffff88807546d080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807546d100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88807546d180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff88807546d200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807546d280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- 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