syzbot

==================================================================
BUG: KASAN: slab-use-after-free in decode_session6 net/xfrm/xfrm_policy.c:3494 [inline]
BUG: KASAN: slab-use-after-free in __xfrm_decode_session+0x18d7/0x20a0 net/xfrm/xfrm_policy.c:3600
Read of size 1 at addr ffff88805f044451 by task syz.4.3635/15671

CPU: 1 PID: 15671 Comm: syz.4.3635 Not tainted 6.6.96-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
 <TASK>
 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_fragment+0x13c5/0x1f90 net/ipv6/ip6_output.c:1023
 __ip6_finish_output net/ipv6/ip6_output.c:206 [inline]
 ip6_finish_output+0x5b4/0xaf0 net/ipv6/ip6_output.c:219
 dst_output include/net/dst.h:467 [inline]
 NF_HOOK include/linux/netfilter.h:304 [inline]
 ip6_xmit+0x10a7/0x1830 net/ipv6/ip6_output.c:360
 sctp_v6_xmit+0x9e3/0x1230 net/sctp/ipv6.c:250
 sctp_packet_transmit+0x2488/0x2a30 net/sctp/output.c:653
 sctp_packet_singleton+0x234/0x330 net/sctp/outqueue.c:783
 sctp_outq_flush_ctrl net/sctp/outqueue.c:914 [inline]
 sctp_outq_flush+0x4f1/0x3100 net/sctp/outqueue.c:1212
 sctp_cmd_interpreter net/sctp/sm_sideeffect.c:-1 [inline]
 sctp_side_effects net/sctp/sm_sideeffect.c:1198 [inline]
 sctp_do_sm+0x52d6/0x59a0 net/sctp/sm_sideeffect.c:1169
 sctp_primitive_ASSOCIATE+0x95/0xc0 net/sctp/primitive.c:73
 __sctp_connect+0x92f/0xd20 net/sctp/socket.c:1234
 sctp_setsockopt+0x458/0x11e0 net/sctp/socket.c:4617
 do_sock_setsockopt+0x254/0x3e0 net/socket.c:2322
 __sys_setsockopt net/socket.c:2345 [inline]
 __do_sys_setsockopt net/socket.c:2354 [inline]
 __se_sys_setsockopt net/socket.c:2351 [inline]
 __x64_sys_setsockopt+0x1be/0x250 net/socket.c:2351
 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: 0033:0x7f0e31d8e929
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:00007f0e32c04038 EFLAGS: 00000246 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 00007f0e31fb6080 RCX: 00007f0e31d8e929
RDX: 000000000000006b RSI: 0000000000000084 RDI: 0000000000000003
RBP: 00007f0e31e10b39 R08: 000000000000001c R09: 0000000000000000
R10: 0000200000000380 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000001 R14: 00007f0e31fb6080 R15: 00007ffef0cc72a8
 </TASK>

Allocated by task 1100:
 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
 kasan_kmalloc include/linux/kasan.h:198 [inline]
 __do_kmalloc_node mm/slab_common.c:1007 [inline]
 __kmalloc+0xb4/0x240 mm/slab_common.c:1020
 kmalloc include/linux/slab.h:604 [inline]
 indx_read+0x28d/0xca0 fs/ntfs3/index.c:1059
 indx_find+0x4ca/0xba0 fs/ntfs3/index.c:1181
 indx_update_dup+0x39e/0x720 fs/ntfs3/index.c:2674
 ni_update_parent+0x6b4/0xbc0 fs/ntfs3/frecord.c:3228
 ni_write_inode+0xd3c/0xf30 fs/ntfs3/frecord.c:3316
 write_inode fs/fs-writeback.c:1473 [inline]
 __writeback_single_inode+0x705/0xee0 fs/fs-writeback.c:1690
 writeback_sb_inodes+0x77c/0xef0 fs/fs-writeback.c:1916
 wb_writeback+0x450/0xba0 fs/fs-writeback.c:2095
 wb_do_writeback fs/fs-writeback.c:2242 [inline]
 wb_workfn+0x3ff/0xe20 fs/fs-writeback.c:2282
 process_one_work kernel/workqueue.c:2634 [inline]
 process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711
 worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792
 kthread+0x2fa/0x390 kernel/kthread.c:388
 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293

Freed by task 1100:
 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
 put_indx_node fs/ntfs3/ntfs_fs.h:1106 [inline]
 fnd_clear+0xcf/0x320 fs/ntfs3/index.c:666
 fnd_put fs/ntfs3/ntfs_fs.h:670 [inline]
 indx_update_dup+0x2fa/0x720 fs/ntfs3/index.c:2713
 ni_update_parent+0x6b4/0xbc0 fs/ntfs3/frecord.c:3228
 ni_write_inode+0xd3c/0xf30 fs/ntfs3/frecord.c:3316
 write_inode fs/fs-writeback.c:1473 [inline]
 __writeback_single_inode+0x705/0xee0 fs/fs-writeback.c:1690
 writeback_sb_inodes+0x77c/0xef0 fs/fs-writeback.c:1916
 wb_writeback+0x450/0xba0 fs/fs-writeback.c:2095
 wb_do_writeback fs/fs-writeback.c:2242 [inline]
 wb_workfn+0x3ff/0xe20 fs/fs-writeback.c:2282
 process_one_work kernel/workqueue.c:2634 [inline]
 process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711
 worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792
 kthread+0x2fa/0x390 kernel/kthread.c:388
 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293

The buggy address belongs to the object at ffff88805f044000
 which belongs to the cache kmalloc-4k of size 4096
The buggy address is located 1105 bytes inside of
 freed 4096-byte region [ffff88805f044000, ffff88805f045000)

The buggy address belongs to the physical page:
page:ffffea00017c1000 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x5f040
head:ffffea00017c1000 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 ffffea0000bfa400 dead000000000002
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 0x1d2820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 42, tgid 42 (kworker/u4:2), ts 152523157009, free_ts 152463787991
 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_node_track_caller+0xa2/0x230 mm/slab_common.c:1027
 kmalloc_reserve+0x117/0x260 net/core/skbuff.c:581
 __alloc_skb+0x138/0x2c0 net/core/skbuff.c:650
 alloc_skb include/linux/skbuff.h:1284 [inline]
 nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:748 [inline]
 nsim_dev_trap_report drivers/net/netdevsim/dev.c:805 [inline]
 nsim_dev_trap_report_work+0x293/0xb00 drivers/net/netdevsim/dev.c:851
 process_one_work kernel/workqueue.c:2634 [inline]
 process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711
 worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792
 kthread+0x2fa/0x390 kernel/kthread.c:388
 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
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
 napi_frag_unref include/linux/skbuff.h:3484 [inline]
 skb_release_data+0x49a/0x800 net/core/skbuff.c:981
 skb_release_all net/core/skbuff.c:1053 [inline]
 __kfree_skb+0x57/0x70 net/core/skbuff.c:1067
 tcp_clean_rtx_queue net/ipv4/tcp_input.c:3444 [inline]
 tcp_ack+0x1fb6/0x65e0 net/ipv4/tcp_input.c:4004
 tcp_rcv_established+0xf23/0x1cf0 net/ipv4/tcp_input.c:6078
 tcp_v4_do_rcv+0x4ed/0xb80 net/ipv4/tcp_ipv4.c:1734
 tcp_v4_rcv+0x2334/0x2a50 net/ipv4/tcp_ipv4.c:2166
 ip_protocol_deliver_rcu+0x20e/0x3f0 net/ipv4/ip_input.c:205
 ip_local_deliver_finish+0x2ca/0x510 net/ipv4/ip_input.c:233
 NF_HOOK+0x303/0x390 include/linux/netfilter.h:304
 dst_input include/net/dst.h:477 [inline]
 ip_sublist_rcv_finish net/ipv4/ip_input.c:580 [inline]
 ip_list_rcv_finish net/ipv4/ip_input.c:631 [inline]
 ip_sublist_rcv+0xa34/0xd20 net/ipv4/ip_input.c:639
 ip_list_rcv+0x3e3/0x430 net/ipv4/ip_input.c:674
 __netif_receive_skb_list_ptype net/core/dev.c:5639 [inline]
 __netif_receive_skb_list_core+0x578/0x740 net/core/dev.c:5687
 __netif_receive_skb_list net/core/dev.c:5739 [inline]
 netif_receive_skb_list_internal+0x91b/0xc60 net/core/dev.c:5830
 gro_normal_list include/net/gro.h:448 [inline]
 napi_complete_done+0x32a/0x810 net/core/dev.c:6170

Memory state around the buggy address:
 ffff88805f044300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88805f044380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88805f044400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                 ^
 ffff88805f044480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88805f044500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================