================================================================== BUG: KASAN: slab-use-after-free in afs_dynroot_readdir_cells fs/afs/dynroot.c:296 [inline] BUG: KASAN: slab-use-after-free in afs_dynroot_readdir+0x99e/0xbe0 fs/afs/dynroot.c:352 Read of size 4 at addr ffff8880797cd948 by task syz.3.102/6409 CPU: 1 UID: 0 PID: 6409 Comm: syz.3.102 Not tainted 6.15.0-rc1-syzkaller-00325-g7cdabafc0012 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:408 [inline] print_report+0x16e/0x5b0 mm/kasan/report.c:521 kasan_report+0x143/0x180 mm/kasan/report.c:634 afs_dynroot_readdir_cells fs/afs/dynroot.c:296 [inline] afs_dynroot_readdir+0x99e/0xbe0 fs/afs/dynroot.c:352 iterate_dir+0x5a9/0x760 fs/readdir.c:108 __do_sys_getdents64 fs/readdir.c:403 [inline] __se_sys_getdents64+0x1e4/0x4c0 fs/readdir.c:389 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fbfd598d169 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:00007fbfd6882038 EFLAGS: 00000246 ORIG_RAX: 00000000000000d9 RAX: ffffffffffffffda RBX: 00007fbfd5ba6080 RCX: 00007fbfd598d169 RDX: 0000000000000022 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 00007fbfd5a0e990 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fbfd5ba6080 R15: 00007ffcb83ff1b8 Allocated by task 6407: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0x9d/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:260 [inline] __kmalloc_cache_noprof+0x236/0x370 mm/slub.c:4362 kmalloc_noprof include/linux/slab.h:905 [inline] kzalloc_noprof include/linux/slab.h:1039 [inline] afs_alloc_cell fs/afs/cell.c:137 [inline] afs_lookup_cell+0x46f/0x18b0 fs/afs/cell.c:264 afs_dynroot_lookup_cell fs/afs/dynroot.c:111 [inline] afs_dynroot_lookup+0x2f9/0x9d0 fs/afs/dynroot.c:159 lookup_one_qstr_excl+0x136/0x3a0 fs/namei.c:1696 do_renameat2+0x675/0x1290 fs/namei.c:5187 __do_sys_rename fs/namei.c:5282 [inline] __se_sys_rename fs/namei.c:5280 [inline] __x64_sys_rename+0x82/0x90 fs/namei.c:5280 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 24: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:576 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x59/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2389 [inline] slab_free mm/slub.c:4646 [inline] kfree+0x198/0x430 mm/slub.c:4845 afs_cell_destroy+0x1a6/0x2c0 fs/afs/cell.c:524 rcu_do_batch kernel/rcu/tree.c:2568 [inline] rcu_core+0xaac/0x17a0 kernel/rcu/tree.c:2824 handle_softirqs+0x2d6/0x9b0 kernel/softirq.c:579 do_softirq+0x11f/0x1e0 kernel/softirq.c:480 __local_bh_enable_ip+0x1be/0x200 kernel/softirq.c:407 spin_unlock_bh include/linux/spinlock.h:396 [inline] ptr_ring_consume_bh include/linux/ptr_ring.h:367 [inline] wg_packet_encrypt_worker+0x2ef/0x1810 drivers/net/wireguard/send.c:293 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xac3/0x18e0 kernel/workqueue.c:3319 worker_thread+0x870/0xd50 kernel/workqueue.c:3400 kthread+0x7b7/0x940 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Last potentially related work creation: kasan_save_stack+0x3f/0x60 mm/kasan/common.c:47 kasan_record_aux_stack+0xbf/0xd0 mm/kasan/generic.c:548 __call_rcu_common kernel/rcu/tree.c:3082 [inline] call_rcu+0x172/0xad0 kernel/rcu/tree.c:3202 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xac3/0x18e0 kernel/workqueue.c:3319 worker_thread+0x870/0xd50 kernel/workqueue.c:3400 kthread+0x7b7/0x940 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Second to last potentially related work creation: kasan_save_stack+0x3f/0x60 mm/kasan/common.c:47 kasan_record_aux_stack+0xbf/0xd0 mm/kasan/generic.c:548 insert_work+0x3e/0x330 kernel/workqueue.c:2183 __queue_work+0xda3/0x10a0 kernel/workqueue.c:2341 queue_work_on+0x1c4/0x380 kernel/workqueue.c:2392 queue_work include/linux/workqueue.h:662 [inline] afs_put_cell+0x13f/0x230 fs/afs/cell.c:569 afs_manage_cell_work+0xd0d/0x17e0 fs/afs/cell.c:859 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xac3/0x18e0 kernel/workqueue.c:3319 worker_thread+0x870/0xd50 kernel/workqueue.c:3400 kthread+0x7b7/0x940 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 The buggy address belongs to the object at ffff8880797cd800 which belongs to the cache kmalloc-1k of size 1024 The buggy address is located 328 bytes inside of freed 1024-byte region [ffff8880797cd800, ffff8880797cdc00) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x797c8 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 anon flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000040 ffff88801b041dc0 0000000000000000 dead000000000001 raw: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000 head: 00fff00000000040 ffff88801b041dc0 0000000000000000 dead000000000001 head: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000 head: 00fff00000000003 ffffea0001e5f201 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008 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 5866, tgid 5866 (syz-executor), ts 98607078049, free_ts 98521995830 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1f4/0x240 mm/page_alloc.c:1717 prep_new_page mm/page_alloc.c:1725 [inline] get_page_from_freelist+0x351d/0x36b0 mm/page_alloc.c:3652 __alloc_frozen_pages_noprof+0x211/0x5b0 mm/page_alloc.c:4934 alloc_pages_mpol+0x339/0x690 mm/mempolicy.c:2301 alloc_slab_page mm/slub.c:2459 [inline] allocate_slab+0x8f/0x3a0 mm/slub.c:2623 new_slab mm/slub.c:2676 [inline] ___slab_alloc+0xc3b/0x1500 mm/slub.c:3862 __slab_alloc+0x58/0xa0 mm/slub.c:3952 __slab_alloc_node mm/slub.c:4027 [inline] slab_alloc_node mm/slub.c:4188 [inline] __do_kmalloc_node mm/slub.c:4330 [inline] __kmalloc_noprof+0x2ea/0x4d0 mm/slub.c:4343 kmalloc_noprof include/linux/slab.h:909 [inline] kzalloc_noprof include/linux/slab.h:1039 [inline] ip6t_alloc_initial_table+0x69/0x6a0 net/ipv6/netfilter/ip6_tables.c:40 ip6table_raw_table_init+0x3d/0x90 net/ipv6/netfilter/ip6table_raw.c:45 xt_find_table_lock+0x322/0x400 net/netfilter/x_tables.c:1260 xt_request_find_table_lock+0x26/0x100 net/netfilter/x_tables.c:1285 get_info net/ipv6/netfilter/ip6_tables.c:979 [inline] do_ip6t_get_ctl+0x949/0x18c0 net/ipv6/netfilter/ip6_tables.c:1668 nf_getsockopt+0x299/0x2c0 net/netfilter/nf_sockopt.c:116 ipv6_getsockopt+0x240/0x360 net/ipv6/ipv6_sockglue.c:1493 tcp_getsockopt+0x16f/0x1d0 net/ipv4/tcp.c:4727 page last free pid 5887 tgid 5887 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1262 [inline] __free_frozen_pages+0xddf/0x10a0 mm/page_alloc.c:2680 discard_slab mm/slub.c:2720 [inline] __put_partials+0x160/0x1c0 mm/slub.c:3189 put_cpu_partial+0x17e/0x250 mm/slub.c:3264 __slab_free+0x294/0x390 mm/slub.c:4516 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x9a/0x140 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x14f/0x170 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x23/0x80 mm/kasan/common.c:329 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4151 [inline] slab_alloc_node mm/slub.c:4200 [inline] __kmalloc_cache_noprof+0x1c8/0x370 mm/slub.c:4357 kmalloc_noprof include/linux/slab.h:905 [inline] kzalloc_noprof include/linux/slab.h:1039 [inline] kset_create lib/kobject.c:965 [inline] kset_create_and_add+0x5b/0x170 lib/kobject.c:1008 register_queue_kobjects net/core/net-sysfs.c:2085 [inline] netdev_register_kobject+0x181/0x2f0 net/core/net-sysfs.c:2340 register_netdevice+0x12b0/0x1b80 net/core/dev.c:11007 __ip_tunnel_create+0x3f0/0x560 net/ipv4/ip_tunnel.c:268 ip_tunnel_init_net+0x2b7/0x810 net/ipv4/ip_tunnel.c:1161 ops_init+0x349/0x5b0 net/core/net_namespace.c:138 setup_net+0x289/0x9f0 net/core/net_namespace.c:364 copy_net_ns+0x33f/0x570 net/core/net_namespace.c:518 Memory state around the buggy address: ffff8880797cd800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880797cd880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8880797cd900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880797cd980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880797cda00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================