================================================================== BUG: KASAN: slab-out-of-bounds in decode_session6 net/xfrm/xfrm_policy.c:3494 [inline] BUG: KASAN: slab-out-of-bounds in __xfrm_decode_session+0x18d7/0x20a0 net/xfrm/xfrm_policy.c:3600 Read of size 1 at addr ffff888028a35dee by task syz.2.873/8715 CPU: 1 PID: 8715 Comm: syz.2.873 Not tainted 6.6.98-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: dump_stack_lvl+0x16c/0x230 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:364 [inline] print_report+0xac/0x230 mm/kasan/report.c:475 kasan_report+0x117/0x150 mm/kasan/report.c:588 decode_session6 net/xfrm/xfrm_policy.c:3494 [inline] __xfrm_decode_session+0x18d7/0x20a0 net/xfrm/xfrm_policy.c:3600 xfrm_decode_session_reverse include/net/xfrm.h:1243 [inline] icmpv6_route_lookup+0x358/0x590 net/ipv6/icmp.c:392 icmp6_send+0x106a/0x1990 net/ipv6/icmp.c:604 __icmpv6_send include/linux/icmpv6.h:28 [inline] icmpv6_send include/linux/icmpv6.h:49 [inline] ip6_link_failure+0x3b/0x4c0 net/ipv6/route.c:2825 dst_link_failure include/net/dst.h:437 [inline] ip6_tnl_xmit+0xdf7/0x2a30 net/ipv6/ip6_tunnel.c:1283 ipxip6_tnl_xmit net/ipv6/ip6_tunnel.c:1399 [inline] ip6_tnl_start_xmit+0xc10/0x1140 net/ipv6/ip6_tunnel.c:1447 __netdev_start_xmit include/linux/netdevice.h:4943 [inline] netdev_start_xmit include/linux/netdevice.h:4957 [inline] xmit_one net/core/dev.c:3607 [inline] dev_hard_start_xmit+0x246/0x740 net/core/dev.c:3623 sch_direct_xmit+0x252/0x4a0 net/sched/sch_generic.c:342 qdisc_restart net/sched/sch_generic.c:407 [inline] __qdisc_run+0xab2/0x1570 net/sched/sch_generic.c:415 __dev_xmit_skb net/core/dev.c:3907 [inline] __dev_queue_xmit+0xf02/0x35a0 net/core/dev.c:4379 neigh_output include/net/neighbour.h:542 [inline] ip6_finish_output2+0xe2e/0x1650 net/ipv6/ip6_output.c:141 __ip6_finish_output net/ipv6/ip6_output.c:208 [inline] ip6_finish_output+0x5d7/0xaf0 net/ipv6/ip6_output.c:219 ip6_send_skb+0x1d5/0x380 net/ipv6/ip6_output.c:2038 rawv6_push_pending_frames+0x6e8/0x8d0 net/ipv6/raw.c:581 rawv6_sendmsg+0x131e/0x17f0 net/ipv6/raw.c:920 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] sock_write_iter+0x2bb/0x3f0 net/socket.c:1160 do_iter_readv_writev fs/read_write.c:-1 [inline] do_iter_write+0x79a/0xc70 fs/read_write.c:860 vfs_writev fs/read_write.c:933 [inline] do_writev+0x252/0x410 fs/read_write.c:976 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fc30f98e929 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fc310762038 EFLAGS: 00000246 ORIG_RAX: 0000000000000014 RAX: ffffffffffffffda RBX: 00007fc30fbb5fa0 RCX: 00007fc30f98e929 RDX: 0000000000000001 RSI: 0000200000000240 RDI: 0000000000000003 RBP: 00007fc30fa10b39 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fc30fbb5fa0 R15: 00007fff91b320c8 Allocated by task 8456: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:52 ____kasan_kmalloc mm/kasan/common.c:374 [inline] __kasan_kmalloc+0x8f/0xa0 mm/kasan/common.c:383 kmalloc include/linux/slab.h:600 [inline] kzalloc include/linux/slab.h:721 [inline] kobject_uevent_env+0x274/0x8c0 lib/kobject_uevent.c:539 netdev_queue_add_kobject net/core/net-sysfs.c:1704 [inline] netdev_queue_update_kobjects+0x243/0x480 net/core/net-sysfs.c:1745 register_queue_kobjects net/core/net-sysfs.c:1806 [inline] netdev_register_kobject+0x269/0x310 net/core/net-sysfs.c:2046 register_netdevice+0x128f/0x1ae0 net/core/dev.c:10268 macvlan_common_newlink+0x1139/0x18f0 drivers/net/macvlan.c:1545 macvtap_newlink+0x154/0x1d0 drivers/net/macvtap.c:108 rtnl_newlink_create net/core/rtnetlink.c:3517 [inline] __rtnl_newlink net/core/rtnetlink.c:3737 [inline] rtnl_newlink+0x14d0/0x2020 net/core/rtnetlink.c:3750 rtnetlink_rcv_msg+0x7c7/0xf10 net/core/rtnetlink.c:6475 netlink_rcv_skb+0x216/0x480 net/netlink/af_netlink.c:2537 netlink_unicast_kernel net/netlink/af_netlink.c:1323 [inline] netlink_unicast+0x750/0x8c0 net/netlink/af_netlink.c:1349 netlink_sendmsg+0x8c1/0xbe0 net/netlink/af_netlink.c:1891 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] __sys_sendto+0x46a/0x620 net/socket.c:2201 __do_sys_sendto net/socket.c:2213 [inline] __se_sys_sendto net/socket.c:2209 [inline] __x64_sys_sendto+0xde/0xf0 net/socket.c:2209 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Freed by task 8456: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:52 kasan_save_free_info+0x2e/0x50 mm/kasan/generic.c:522 ____kasan_slab_free+0x126/0x1e0 mm/kasan/common.c:236 kasan_slab_free include/linux/kasan.h:164 [inline] slab_free_hook mm/slub.c:1806 [inline] slab_free_freelist_hook+0x130/0x1b0 mm/slub.c:1832 slab_free mm/slub.c:3816 [inline] __kmem_cache_free+0xba/0x1f0 mm/slub.c:3829 kobject_uevent_env+0x363/0x8c0 lib/kobject_uevent.c:641 netdev_queue_add_kobject net/core/net-sysfs.c:1704 [inline] netdev_queue_update_kobjects+0x243/0x480 net/core/net-sysfs.c:1745 register_queue_kobjects net/core/net-sysfs.c:1806 [inline] netdev_register_kobject+0x269/0x310 net/core/net-sysfs.c:2046 register_netdevice+0x128f/0x1ae0 net/core/dev.c:10268 macvlan_common_newlink+0x1139/0x18f0 drivers/net/macvlan.c:1545 macvtap_newlink+0x154/0x1d0 drivers/net/macvtap.c:108 rtnl_newlink_create net/core/rtnetlink.c:3517 [inline] __rtnl_newlink net/core/rtnetlink.c:3737 [inline] rtnl_newlink+0x14d0/0x2020 net/core/rtnetlink.c:3750 rtnetlink_rcv_msg+0x7c7/0xf10 net/core/rtnetlink.c:6475 netlink_rcv_skb+0x216/0x480 net/netlink/af_netlink.c:2537 netlink_unicast_kernel net/netlink/af_netlink.c:1323 [inline] netlink_unicast+0x750/0x8c0 net/netlink/af_netlink.c:1349 netlink_sendmsg+0x8c1/0xbe0 net/netlink/af_netlink.c:1891 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] __sys_sendto+0x46a/0x620 net/socket.c:2201 __do_sys_sendto net/socket.c:2213 [inline] __se_sys_sendto net/socket.c:2209 [inline] __x64_sys_sendto+0xde/0xf0 net/socket.c:2209 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 The buggy address belongs to the object at ffff888028a34000 which belongs to the cache kmalloc-4k of size 4096 The buggy address is located 3566 bytes to the right of allocated 4096-byte region [ffff888028a34000, ffff888028a35000) The buggy address belongs to the physical page: page:ffffea0000a28c00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x28a30 head:ffffea0000a28c00 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 ffff888017842140 dead000000000100 dead000000000122 raw: 0000000000000000 0000000000040004 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 0xd2040(__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5162, tgid 5162 (udevd), ts 25111005821, free_ts 25102638226 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x1cd/0x210 mm/page_alloc.c:1554 prep_new_page mm/page_alloc.c:1561 [inline] get_page_from_freelist+0x195c/0x19f0 mm/page_alloc.c:3191 __alloc_pages+0x1e3/0x460 mm/page_alloc.c:4457 alloc_slab_page+0x5d/0x170 mm/slub.c:1876 allocate_slab mm/slub.c:2023 [inline] new_slab+0x87/0x2e0 mm/slub.c:2076 ___slab_alloc+0xc6d/0x12f0 mm/slub.c:3230 __slab_alloc mm/slub.c:3329 [inline] __slab_alloc_node mm/slub.c:3382 [inline] slab_alloc_node mm/slub.c:3475 [inline] __kmem_cache_alloc_node+0x1a2/0x260 mm/slub.c:3524 __do_kmalloc_node mm/slab_common.c:1006 [inline] __kmalloc+0xa4/0x240 mm/slab_common.c:1020 kmalloc include/linux/slab.h:604 [inline] tomoyo_realpath_from_path+0xe3/0x5d0 security/tomoyo/realpath.c:251 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_check_open_permission+0x1c3/0x3c0 security/tomoyo/file.c:771 security_file_open+0x62/0xa0 security/security.c:2854 do_dentry_open+0x380/0x1500 fs/open.c:916 do_open fs/namei.c:3632 [inline] path_openat+0x274b/0x3190 fs/namei.c:3789 do_filp_open+0x1c5/0x3d0 fs/namei.c:3816 do_sys_openat2+0x12c/0x1c0 fs/open.c:1419 do_sys_open fs/open.c:1434 [inline] __do_sys_openat fs/open.c:1450 [inline] __se_sys_openat fs/open.c:1445 [inline] __x64_sys_openat+0x139/0x160 fs/open.c:1445 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1154 [inline] free_unref_page_prepare+0x7ce/0x8e0 mm/page_alloc.c:2336 free_unref_page+0x32/0x2e0 mm/page_alloc.c:2429 discard_slab mm/slub.c:2122 [inline] __unfreeze_partials+0x1cf/0x210 mm/slub.c:2662 put_cpu_partial+0x17c/0x250 mm/slub.c:2738 __slab_free+0x31d/0x410 mm/slub.c:3686 qlink_free mm/kasan/quarantine.c:166 [inline] qlist_free_all+0x75/0xe0 mm/kasan/quarantine.c:185 kasan_quarantine_reduce+0x143/0x160 mm/kasan/quarantine.c:292 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:305 kasan_slab_alloc include/linux/kasan.h:188 [inline] slab_post_alloc_hook+0x6e/0x4d0 mm/slab.h:767 slab_alloc_node mm/slub.c:3485 [inline] __kmem_cache_alloc_node+0x13e/0x260 mm/slub.c:3524 __do_kmalloc_node mm/slab_common.c:1006 [inline] __kmalloc_node+0xa4/0x230 mm/slab_common.c:1014 kmalloc_node include/linux/slab.h:620 [inline] kvmalloc_node+0x70/0x180 mm/util.c:617 kvmalloc include/linux/slab.h:738 [inline] seq_buf_alloc fs/seq_file.c:38 [inline] seq_read_iter+0x1fa/0xd50 fs/seq_file.c:210 call_read_iter include/linux/fs.h:2012 [inline] new_sync_read fs/read_write.c:389 [inline] vfs_read+0x431/0x920 fs/read_write.c:470 ksys_read+0x147/0x250 fs/read_write.c:613 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81 Memory state around the buggy address: ffff888028a35c80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888028a35d00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff888028a35d80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff888028a35e00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888028a35e80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================