================================================================== BUG: KASAN: slab-use-after-free in decode_session6+0x10e1/0x1950 net/xfrm/xfrm_policy.c:3460 Read of size 1 at addr ffff888023b28aa1 by task syz-executor.0/20733 CPU: 1 PID: 20733 Comm: syz-executor.0 Not tainted 6.5.0-syzkaller-03967-gbd6c11bc43c4 #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:2784 dst_link_failure include/net/dst.h:437 [inline] ip6_tnl_xmit+0x4f9/0x3950 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:4889 [inline] netdev_start_xmit include/linux/netdevice.h:4903 [inline] xmit_one net/core/dev.c:3544 [inline] dev_hard_start_xmit+0x13d/0x6c0 net/core/dev.c:3560 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:3834 [inline] __dev_queue_xmit+0x24f9/0x3d80 net/core/dev.c:4306 dev_queue_xmit include/linux/netdevice.h:3082 [inline] neigh_connected_output+0x42c/0x5d0 net/core/neighbour.c:1581 neigh_output include/net/neighbour.h:542 [inline] ip6_finish_output2+0x610/0x1b20 net/ipv6/ip6_output.c:135 __ip6_finish_output net/ipv6/ip6_output.c:196 [inline] ip6_finish_output+0x485/0x1250 net/ipv6/ip6_output.c:207 NF_HOOK_COND include/linux/netfilter.h:293 [inline] ip6_output+0x23a/0x880 net/ipv6/ip6_output.c:228 dst_output include/net/dst.h:458 [inline] NF_HOOK include/linux/netfilter.h:304 [inline] NF_HOOK include/linux/netfilter.h:298 [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+0x1a30/0x3b30 net/ipv4/tcp_output.c:1416 tcp_transmit_skb net/ipv4/tcp_output.c:1434 [inline] tcp_send_syn_data net/ipv4/tcp_output.c:3898 [inline] tcp_connect+0x20f9/0x5430 net/ipv4/tcp_output.c:3963 tcp_v6_connect+0x147f/0x1fc0 net/ipv6/tcp_ipv6.c:338 __inet_stream_connect+0x38b/0xe20 net/ipv4/af_inet.c:676 tcp_sendmsg_fastopen+0x3d2/0x700 net/ipv4/tcp.c:1021 tcp_sendmsg_locked+0x1ed4/0x3430 net/ipv4/tcp.c:1073 tcp_sendmsg+0x2e/0x40 net/ipv4/tcp.c:1336 inet6_sendmsg+0x9d/0xe0 net/ipv6/af_inet6.c:655 sock_sendmsg_nosec net/socket.c:728 [inline] sock_sendmsg+0xd9/0x180 net/socket.c:751 __sys_sendto+0x255/0x340 net/socket.c:2174 __do_sys_sendto net/socket.c:2186 [inline] __se_sys_sendto net/socket.c:2182 [inline] __x64_sys_sendto+0xe0/0x1b0 net/socket.c:2182 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 RIP: 0033:0x7fe67227cae9 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:00007fe672f060c8 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00007fe67239bf80 RCX: 00007fe67227cae9 RDX: 0000000000000001 RSI: 00000000200000c0 RDI: 0000000000000003 RBP: 00007fe6722c847a R08: 0000000020000040 R09: 000000000000001c R10: 0000000020008845 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007fe67239bf80 R15: 00007ffec673de08 Allocated by task 14219: 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 kasan_kmalloc include/linux/kasan.h:196 [inline] __do_kmalloc_node mm/slab_common.c:985 [inline] __kmalloc_node_track_caller+0x5e/0x100 mm/slab_common.c:1005 kmalloc_reserve+0xef/0x270 net/core/skbuff.c:575 __alloc_skb+0x12b/0x330 net/core/skbuff.c:644 alloc_skb include/linux/skbuff.h:1286 [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+0x29e/0xc70 drivers/net/netdevsim/dev.c:850 process_one_work+0xaa2/0x16f0 kernel/workqueue.c:2600 worker_thread+0x687/0x1110 kernel/workqueue.c:2751 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 Freed by task 14219: 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 skb_kfree_head net/core/skbuff.c:939 [inline] skb_free_head+0x110/0x1b0 net/core/skbuff.c:951 skb_release_data+0x5ba/0x870 net/core/skbuff.c:981 skb_release_all net/core/skbuff.c:1047 [inline] __kfree_skb net/core/skbuff.c:1061 [inline] consume_skb net/core/skbuff.c:1277 [inline] consume_skb+0xd2/0x170 net/core/skbuff.c:1271 nsim_dev_trap_report drivers/net/netdevsim/dev.c:821 [inline] nsim_dev_trap_report_work+0x872/0xc70 drivers/net/netdevsim/dev.c:850 process_one_work+0xaa2/0x16f0 kernel/workqueue.c:2600 worker_thread+0x687/0x1110 kernel/workqueue.c:2751 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 ffff888023b28000 which belongs to the cache kmalloc-4k of size 4096 The buggy address is located 2721 bytes inside of freed 4096-byte region [ffff888023b28000, ffff888023b29000) The buggy address belongs to the physical page: page:ffffea00008eca00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x23b28 head:ffffea00008eca00 order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000010200 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 0x1d2820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 5127, tgid 5127 (kworker/0:5), ts 349390724152, free_ts 337636874974 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:2298 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 __alloc_skb+0x12b/0x330 net/core/skbuff.c:644 alloc_skb include/linux/skbuff.h:1286 [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+0x29e/0xc70 drivers/net/netdevsim/dev.c:850 process_one_work+0xaa2/0x16f0 kernel/workqueue.c:2600 worker_thread+0x687/0x1110 kernel/workqueue.c:2751 kthread+0x33a/0x430 kernel/kthread.c:389 ret_from_fork+0x2c/0x70 arch/x86/kernel/process.c:145 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 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] slab_alloc mm/slub.c:3478 [inline] __kmem_cache_alloc_lru mm/slub.c:3485 [inline] kmem_cache_alloc+0x172/0x3b0 mm/slub.c:3494 getname_flags.part.0+0x50/0x4d0 fs/namei.c:140 getname_flags+0x9c/0xf0 include/linux/audit.h:319 user_path_at_empty+0x2c/0x60 fs/namei.c:2909 do_readlinkat+0xdd/0x2f0 fs/stat.c:516 __do_sys_readlink fs/stat.c:549 [inline] __se_sys_readlink fs/stat.c:546 [inline] __x64_sys_readlink+0x78/0xb0 fs/stat.c:546 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: ffff888023b28980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888023b28a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888023b28a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888023b28b00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888023b28b80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================