================================================================== BUG: KASAN: slab-use-after-free in decode_session6 net/xfrm/xfrm_policy.c:3460 [inline] BUG: KASAN: slab-use-after-free in __xfrm_decode_session+0x1a49/0x2450 net/xfrm/xfrm_policy.c:3566 Read of size 1 at addr ffff8880265a2026 by task syz-executor.1/20706 CPU: 1 PID: 20706 Comm: syz-executor.1 Not tainted 6.6.0-rc1-syzkaller-00072-gaed8aee11130 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/04/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:364 [inline] print_report+0x163/0x540 mm/kasan/report.c:475 kasan_report+0x175/0x1b0 mm/kasan/report.c:588 decode_session6 net/xfrm/xfrm_policy.c:3460 [inline] __xfrm_decode_session+0x1a49/0x2450 net/xfrm/xfrm_policy.c:3566 xfrm_decode_session_reverse include/net/xfrm.h:1223 [inline] icmpv6_route_lookup+0x4b3/0x730 net/ipv6/icmp.c:388 icmp6_send+0x125c/0x20e0 net/ipv6/icmp.c:595 __icmpv6_send include/linux/icmpv6.h:28 [inline] icmpv6_send include/linux/icmpv6.h:49 [inline] ip6_link_failure+0x3b/0x4a0 net/ipv6/route.c:2787 dst_link_failure include/net/dst.h:437 [inline] ip6_tnl_xmit+0xda6/0x2860 net/ipv6/ip6_tunnel.c:1268 ipxip6_tnl_xmit net/ipv6/ip6_tunnel.c:1384 [inline] ip6_tnl_start_xmit+0xb8a/0x13f0 net/ipv6/ip6_tunnel.c:1432 __netdev_start_xmit include/linux/netdevice.h:4889 [inline] netdev_start_xmit include/linux/netdevice.h:4903 [inline] xmit_one net/core/dev.c:3544 [inline] dev_hard_start_xmit+0x241/0x750 net/core/dev.c:3560 sch_direct_xmit+0x2b6/0x5f0 net/sched/sch_generic.c:342 qdisc_restart net/sched/sch_generic.c:407 [inline] __qdisc_run+0xa8c/0x1f80 net/sched/sch_generic.c:415 __dev_xmit_skb net/core/dev.c:3834 [inline] __dev_queue_xmit+0x13ae/0x3a60 net/core/dev.c:4306 neigh_output include/net/neighbour.h:542 [inline] ip6_finish_output2+0xf84/0x1560 net/ipv6/ip6_output.c:135 __ip6_finish_output net/ipv6/ip6_output.c:196 [inline] ip6_finish_output+0x6b0/0xb00 net/ipv6/ip6_output.c:207 ip6_send_skb+0x12f/0x250 net/ipv6/ip6_output.c:2017 rawv6_push_pending_frames+0x7c3/0xa40 net/ipv6/raw.c:581 rawv6_sendmsg+0x189e/0x22e0 net/ipv6/raw.c:920 sock_sendmsg_nosec net/socket.c:730 [inline] sock_sendmsg net/socket.c:753 [inline] ____sys_sendmsg+0x592/0x890 net/socket.c:2541 ___sys_sendmsg net/socket.c:2595 [inline] __sys_sendmsg+0x2b0/0x3a0 net/socket.c:2624 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f22f687cae9 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:00007f22f75e40c8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f22f699bf80 RCX: 00007f22f687cae9 RDX: 0000000000000000 RSI: 0000000020000080 RDI: 0000000000000003 RBP: 00007f22f68c847a R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007f22f699bf80 R15: 00007fff2c981998 Allocated by task 16669: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4f/0x70 mm/kasan/common.c:52 ____kasan_kmalloc mm/kasan/common.c:374 [inline] __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:383 kasan_kmalloc include/linux/kasan.h:198 [inline] __do_kmalloc_node mm/slab_common.c:1023 [inline] __kmalloc+0xb9/0x230 mm/slab_common.c:1036 kmalloc include/linux/slab.h:603 [inline] tomoyo_realpath_from_path+0xcf/0x5e0 security/tomoyo/realpath.c:251 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_check_open_permission+0x254/0x4e0 security/tomoyo/file.c:771 security_file_open+0x63/0xa0 security/security.c:2836 do_dentry_open+0x325/0x1430 fs/open.c:916 do_open fs/namei.c:3639 [inline] path_openat+0x27bb/0x3180 fs/namei.c:3796 do_filp_open+0x234/0x490 fs/namei.c:3823 do_sys_openat2+0x13e/0x1d0 fs/open.c:1422 do_sys_open fs/open.c:1437 [inline] __do_sys_openat fs/open.c:1453 [inline] __se_sys_openat fs/open.c:1448 [inline] __x64_sys_openat+0x247/0x290 fs/open.c:1448 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Freed by task 16669: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4f/0x70 mm/kasan/common.c:52 kasan_save_free_info+0x28/0x40 mm/kasan/generic.c:522 ____kasan_slab_free+0xd6/0x120 mm/kasan/common.c:236 kasan_slab_free include/linux/kasan.h:164 [inline] slab_free_hook mm/slub.c:1800 [inline] slab_free_freelist_hook mm/slub.c:1826 [inline] slab_free mm/slub.c:3809 [inline] __kmem_cache_free+0x25f/0x3b0 mm/slub.c:3822 tomoyo_realpath_from_path+0x5a3/0x5e0 security/tomoyo/realpath.c:286 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_check_open_permission+0x254/0x4e0 security/tomoyo/file.c:771 security_file_open+0x63/0xa0 security/security.c:2836 do_dentry_open+0x325/0x1430 fs/open.c:916 do_open fs/namei.c:3639 [inline] path_openat+0x27bb/0x3180 fs/namei.c:3796 do_filp_open+0x234/0x490 fs/namei.c:3823 do_sys_openat2+0x13e/0x1d0 fs/open.c:1422 do_sys_open fs/open.c:1437 [inline] __do_sys_openat fs/open.c:1453 [inline] __se_sys_openat fs/open.c:1448 [inline] __x64_sys_openat+0x247/0x290 fs/open.c:1448 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Last potentially related work creation: kasan_save_stack+0x3f/0x60 mm/kasan/common.c:45 __kasan_record_aux_stack+0xad/0xc0 mm/kasan/generic.c:492 insert_work+0x3e/0x320 kernel/workqueue.c:1647 __queue_work+0xc2d/0xff0 kernel/workqueue.c:1799 queue_work_on+0x14f/0x250 kernel/workqueue.c:1834 rcu_do_batch kernel/rcu/tree.c:2139 [inline] rcu_core+0xaaa/0x1740 kernel/rcu/tree.c:2403 __do_softirq+0x2ab/0x908 kernel/softirq.c:553 Second to last potentially related work creation: kasan_save_stack+0x3f/0x60 mm/kasan/common.c:45 __kasan_record_aux_stack+0xad/0xc0 mm/kasan/generic.c:492 __call_rcu_common kernel/rcu/tree.c:2653 [inline] call_rcu+0x167/0xa70 kernel/rcu/tree.c:2767 put_super fs/super.c:433 [inline] deactivate_locked_super+0xe0/0x110 fs/super.c:494 cleanup_mnt+0x426/0x4c0 fs/namespace.c:1254 task_work_run+0x24a/0x300 kernel/task_work.c:179 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop+0xd9/0x100 kernel/entry/common.c:171 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:204 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline] syscall_exit_to_user_mode+0x64/0x280 kernel/entry/common.c:296 do_syscall_64+0x4d/0xc0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x63/0xcd The buggy address belongs to the object at ffff8880265a2000 which belongs to the cache kmalloc-4k of size 4096 The buggy address is located 38 bytes inside of freed 4096-byte region [ffff8880265a2000, ffff8880265a3000) The buggy address belongs to the physical page: page:ffffea0000996800 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x265a0 head:ffffea0000996800 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 ffff888012842140 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 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5061, tgid 5061 (syz-executor.4), ts 89627325036, free_ts 83745091098 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x1e6/0x210 mm/page_alloc.c:1536 prep_new_page mm/page_alloc.c:1543 [inline] get_page_from_freelist+0x31db/0x3360 mm/page_alloc.c:3170 __alloc_pages+0x255/0x670 mm/page_alloc.c:4426 alloc_slab_page+0x6a/0x160 mm/slub.c:1870 allocate_slab mm/slub.c:2017 [inline] new_slab+0x84/0x2f0 mm/slub.c:2070 ___slab_alloc+0xade/0x1100 mm/slub.c:3223 __slab_alloc mm/slub.c:3322 [inline] __slab_alloc_node mm/slub.c:3375 [inline] slab_alloc_node mm/slub.c:3468 [inline] __kmem_cache_alloc_node+0x1af/0x270 mm/slub.c:3517 __do_kmalloc_node mm/slab_common.c:1022 [inline] __kmalloc_node+0xa7/0x230 mm/slab_common.c:1030 kmalloc_node include/linux/slab.h:619 [inline] kvmalloc_node+0x72/0x180 mm/util.c:607 kvmalloc include/linux/slab.h:737 [inline] kvmalloc_array include/linux/slab.h:755 [inline] unix_net_init+0x120/0x2a0 net/unix/af_unix.c:3538 ops_init+0x351/0x600 net/core/net_namespace.c:136 setup_net+0x4d1/0xbb0 net/core/net_namespace.c:339 copy_net_ns+0x4e3/0x7a0 net/core/net_namespace.c:491 create_new_namespaces+0x425/0x7a0 kernel/nsproxy.c:110 unshare_nsproxy_namespaces+0x122/0x170 kernel/nsproxy.c:228 ksys_unshare+0x584/0xb20 kernel/fork.c:3435 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+0x8c3/0x9f0 mm/page_alloc.c:2312 free_unref_page+0x37/0x3f0 mm/page_alloc.c:2405 discard_slab mm/slub.c:2116 [inline] __unfreeze_partials+0x1dc/0x220 mm/slub.c:2655 put_cpu_partial+0x116/0x180 mm/slub.c:2731 __slab_free+0x2b6/0x390 mm/slub.c:3679 qlist_free_all+0x22/0x60 mm/kasan/quarantine.c:185 kasan_quarantine_reduce+0x14b/0x160 mm/kasan/quarantine.c:292 __kasan_slab_alloc+0x23/0x70 mm/kasan/common.c:305 kasan_slab_alloc include/linux/kasan.h:188 [inline] slab_post_alloc_hook+0x6c/0x3b0 mm/slab.h:762 slab_alloc_node mm/slub.c:3478 [inline] kmem_cache_alloc_node+0x148/0x330 mm/slub.c:3523 __alloc_skb+0x181/0x420 net/core/skbuff.c:640 alloc_skb_fclone include/linux/skbuff.h:1336 [inline] tcp_stream_alloc_skb+0x3d/0x310 net/ipv4/tcp.c:869 tcp_sendmsg_locked+0x1b24/0x5000 net/ipv4/tcp.c:1150 tcp_sendmsg+0x30/0x50 net/ipv4/tcp.c:1336 sock_sendmsg_nosec net/socket.c:730 [inline] sock_sendmsg net/socket.c:753 [inline] sock_write_iter+0x39a/0x520 net/socket.c:1141 call_write_iter include/linux/fs.h:1985 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x782/0xaf0 fs/read_write.c:584 Memory state around the buggy address: ffff8880265a1f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8880265a1f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff8880265a2000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880265a2080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880265a2100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================