================================================================== BUG: KASAN: slab-use-after-free in decode_session6+0x10e1/0x1950 net/xfrm/xfrm_policy.c:3460 Read of size 1 at addr ffff88802a9fdc77 by task syz-executor.0/32270 CPU: 0 PID: 32270 Comm: syz-executor.0 Not tainted 6.5.0-syzkaller-12728-ga48fa7efaf11 #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_ndo_send+0x143/0x620 net/ipv6/ip6_icmp.c:62 ipxip6_tnl_xmit net/ipv6/ip6_tunnel.c:1336 [inline] ip6_tnl_start_xmit+0x1557/0x1750 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] ip6_local_out+0xaf/0x190 net/ipv6/output_core.c:155 ip6_send_skb+0xb7/0x330 net/ipv6/ip6_output.c:2017 udp_v6_send_skb+0x9b2/0x1900 net/ipv6/udp.c:1282 udpv6_sendmsg+0x24d1/0x2fa0 net/ipv6/udp.c:1576 inet6_sendmsg+0x9d/0xe0 net/ipv6/af_inet6.c:655 sock_sendmsg_nosec net/socket.c:730 [inline] sock_sendmsg+0xd9/0x180 net/socket.c:753 ____sys_sendmsg+0x6ac/0x940 net/socket.c:2541 ___sys_sendmsg+0x135/0x1d0 net/socket.c:2595 __sys_sendmsg+0x117/0x1e0 net/socket.c:2624 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: 0033:0x7f0aa6e7cae9 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:00007f0aa7c780c8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f0aa6f9bf80 RCX: 00007f0aa6e7cae9 RDX: 0000000000000000 RSI: 0000000020001680 RDI: 0000000000000003 RBP: 00007f0aa6ec847a R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007f0aa6f9bf80 R15: 00007f0aa70bfa48 Allocated by task 5095: 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:3478 [inline] slab_alloc mm/slub.c:3486 [inline] __kmem_cache_alloc_lru mm/slub.c:3493 [inline] kmem_cache_alloc+0x172/0x3b0 mm/slub.c:3502 getname_flags.part.0+0x50/0x4d0 fs/namei.c:140 getname_flags include/linux/audit.h:321 [inline] getname+0x90/0xe0 fs/namei.c:219 do_sys_openat2+0x100/0x1e0 fs/open.c:1416 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+0x175/0x210 fs/open.c:1448 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 Freed by task 5095: 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+0x15b/0x1b0 mm/kasan/common.c:200 kasan_slab_free include/linux/kasan.h:162 [inline] slab_free_hook mm/slub.c:1800 [inline] slab_free_freelist_hook+0x114/0x1e0 mm/slub.c:1826 slab_free mm/slub.c:3809 [inline] kmem_cache_free+0xf0/0x480 mm/slub.c:3831 putname fs/namei.c:273 [inline] putname+0x101/0x140 fs/namei.c:259 do_sys_openat2+0x15c/0x1e0 fs/open.c:1430 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+0x175/0x210 fs/open.c:1448 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 ffff88802a9fd500 which belongs to the cache names_cache of size 4096 The buggy address is located 1911 bytes inside of freed 4096-byte region [ffff88802a9fd500, ffff88802a9fe500) The buggy address belongs to the physical page: page:ffffea0000aa7e00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2a9f8 head:ffffea0000aa7e00 order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0 anon flags: 0xfff00000000840(slab|head|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000840 ffff888014e4a780 0000000000000000 dead000000000001 raw: 0000000000000000 0000000000070007 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 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 25199, tgid 25199 (syz-executor.2), ts 1356881039971, free_ts 1356853698383 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x2cf/0x340 mm/page_alloc.c:1536 prep_new_page mm/page_alloc.c:1543 [inline] get_page_from_freelist+0xee0/0x2f20 mm/page_alloc.c:3170 __alloc_pages+0x1d0/0x4a0 mm/page_alloc.c:4426 alloc_pages+0x1a9/0x270 mm/mempolicy.c:2298 alloc_slab_page mm/slub.c:1870 [inline] allocate_slab+0x251/0x380 mm/slub.c:2017 new_slab mm/slub.c:2070 [inline] ___slab_alloc+0x8be/0x1570 mm/slub.c:3223 __slab_alloc.constprop.0+0x56/0xa0 mm/slub.c:3322 __slab_alloc_node mm/slub.c:3375 [inline] slab_alloc_node mm/slub.c:3468 [inline] slab_alloc mm/slub.c:3486 [inline] __kmem_cache_alloc_lru mm/slub.c:3493 [inline] kmem_cache_alloc+0x392/0x3b0 mm/slub.c:3502 getname_flags.part.0+0x50/0x4d0 fs/namei.c:140 getname_flags+0x9c/0xf0 include/linux/audit.h:321 getname fs/namei.c:219 [inline] __do_sys_symlinkat fs/namei.c:4522 [inline] __se_sys_symlinkat fs/namei.c:4519 [inline] __x64_sys_symlinkat+0x8a/0xc0 fs/namei.c:4519 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 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+0x476/0xa40 mm/page_alloc.c:2312 free_unref_page+0x33/0x3b0 mm/page_alloc.c:2405 __unfreeze_partials+0x21d/0x240 mm/slub.c:2655 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:3478 [inline] slab_alloc mm/slub.c:3486 [inline] __kmem_cache_alloc_lru mm/slub.c:3493 [inline] kmem_cache_alloc+0x172/0x3b0 mm/slub.c:3502 getname_flags.part.0+0x50/0x4d0 fs/namei.c:140 getname_flags+0x9c/0xf0 include/linux/audit.h:321 user_path_at_empty+0x2c/0x60 fs/namei.c:2909 user_path_at include/linux/namei.h:57 [inline] ksys_umount fs/namespace.c:1914 [inline] __do_sys_umount fs/namespace.c:1922 [inline] __se_sys_umount fs/namespace.c:1920 [inline] __x64_sys_umount+0x10e/0x1a0 fs/namespace.c:1920 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: ffff88802a9fdb00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88802a9fdb80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88802a9fdc00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88802a9fdc80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88802a9fdd00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================