================================================================== BUG: KASAN: slab-use-after-free in instrument_atomic_read_write include/linux/instrumented.h:96 [inline] BUG: KASAN: slab-use-after-free in test_and_set_bit include/asm-generic/bitops/instrumented-atomic.h:71 [inline] BUG: KASAN: slab-use-after-free in l2tp_session_delete+0x28/0x9e0 net/l2tp/l2tp_core.c:1639 Write of size 8 at addr ffff88802d75e008 by task kworker/u8:5/1093 CPU: 1 UID: 0 PID: 1093 Comm: kworker/u8:5 Not tainted 6.10.0-rc4-next-20240621-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024 Workqueue: l2tp l2tp_tunnel_del_work 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:377 [inline] print_report+0x169/0x550 mm/kasan/report.c:488 kasan_report+0x143/0x180 mm/kasan/report.c:601 kasan_check_range+0x282/0x290 mm/kasan/generic.c:189 instrument_atomic_read_write include/linux/instrumented.h:96 [inline] test_and_set_bit include/asm-generic/bitops/instrumented-atomic.h:71 [inline] l2tp_session_delete+0x28/0x9e0 net/l2tp/l2tp_core.c:1639 l2tp_tunnel_closeall net/l2tp/l2tp_core.c:1302 [inline] l2tp_tunnel_del_work+0x1cb/0x330 net/l2tp/l2tp_core.c:1334 process_one_work kernel/workqueue.c:3224 [inline] process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3305 worker_thread+0x86d/0xd50 kernel/workqueue.c:3385 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:144 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Allocated by task 5095: 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:370 [inline] __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:387 kasan_kmalloc include/linux/kasan.h:211 [inline] __do_kmalloc_node mm/slub.c:4158 [inline] __kmalloc_noprof+0x1f9/0x400 mm/slub.c:4171 kmalloc_noprof include/linux/slab.h:664 [inline] kzalloc_noprof include/linux/slab.h:778 [inline] l2tp_session_create+0x3b/0xc20 net/l2tp/l2tp_core.c:1675 pppol2tp_connect+0xca3/0x17a0 net/l2tp/l2tp_ppp.c:782 __sys_connect_file net/socket.c:2061 [inline] __sys_connect+0x2df/0x310 net/socket.c:2078 __do_sys_connect net/socket.c:2088 [inline] __se_sys_connect net/socket.c:2085 [inline] __x64_sys_connect+0x7a/0x90 net/socket.c:2085 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 5101: 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:579 poison_slab_object+0xe0/0x150 mm/kasan/common.c:240 __kasan_slab_free+0x37/0x60 mm/kasan/common.c:256 kasan_slab_free include/linux/kasan.h:184 [inline] slab_free_hook mm/slub.c:2231 [inline] slab_free mm/slub.c:4473 [inline] kfree+0x149/0x360 mm/slub.c:4594 __sk_destruct+0x58/0x5f0 net/core/sock.c:2191 rcu_do_batch kernel/rcu/tree.c:2542 [inline] rcu_core+0xaaa/0x17a0 kernel/rcu/tree.c:2798 handle_softirqs+0x2c4/0x970 kernel/softirq.c:554 do_softirq+0x11b/0x1e0 kernel/softirq.c:455 __local_bh_enable_ip+0x1bb/0x200 kernel/softirq.c:382 l2tp_tunnel_get+0x40d/0x500 pppol2tp_tunnel_get net/l2tp/l2tp_ppp.c:662 [inline] pppol2tp_connect+0x6b3/0x17a0 net/l2tp/l2tp_ppp.c:737 __sys_connect_file net/socket.c:2061 [inline] __sys_connect+0x2df/0x310 net/socket.c:2078 __do_sys_connect net/socket.c:2088 [inline] __se_sys_connect net/socket.c:2085 [inline] __x64_sys_connect+0x7a/0x90 net/socket.c:2085 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f Last potentially related work creation: kasan_save_stack+0x3f/0x60 mm/kasan/common.c:47 __kasan_record_aux_stack+0xac/0xc0 mm/kasan/generic.c:541 __call_rcu_common kernel/rcu/tree.c:3061 [inline] call_rcu+0x167/0xa70 kernel/rcu/tree.c:3165 pppol2tp_release+0x24b/0x350 net/l2tp/l2tp_ppp.c:457 __sock_release net/socket.c:659 [inline] sock_close+0xbc/0x240 net/socket.c:1421 __fput+0x24a/0x8a0 fs/file_table.c:422 task_work_run+0x24f/0x310 kernel/task_work.c:180 exit_task_work include/linux/task_work.h:38 [inline] do_exit+0xa27/0x28e0 kernel/exit.c:876 do_group_exit+0x207/0x2c0 kernel/exit.c:1025 __do_sys_exit_group kernel/exit.c:1036 [inline] __se_sys_exit_group kernel/exit.c:1034 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1034 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff88802d75e000 which belongs to the cache kmalloc-1k of size 1024 The buggy address is located 8 bytes inside of freed 1024-byte region [ffff88802d75e000, ffff88802d75e400) The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2d758 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffefff(slab) raw: 00fff00000000040 ffff888015041dc0 dead000000000100 dead000000000122 raw: 0000000000000000 0000000000100010 00000001ffffefff 0000000000000000 head: 00fff00000000040 ffff888015041dc0 dead000000000100 dead000000000122 head: 0000000000000000 0000000000100010 00000001ffffefff 0000000000000000 head: 00fff00000000003 ffffea0000b5d601 ffffffffffffffff 0000000000000000 head: 0000000000000008 0000000000000000 00000000ffffffff 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 4717, tgid 4717 (udevd), ts 27477638703, free_ts 27187740744 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1500 prep_new_page mm/page_alloc.c:1508 [inline] get_page_from_freelist+0x2ccb/0x2d80 mm/page_alloc.c:3487 __alloc_pages_noprof+0x256/0x6c0 mm/page_alloc.c:4745 __alloc_pages_node_noprof include/linux/gfp.h:269 [inline] alloc_pages_node_noprof include/linux/gfp.h:296 [inline] alloc_slab_page+0x5f/0x120 mm/slub.c:2300 allocate_slab+0x5a/0x2f0 mm/slub.c:2463 new_slab mm/slub.c:2516 [inline] ___slab_alloc+0xcd1/0x14b0 mm/slub.c:3702 __slab_alloc+0x58/0xa0 mm/slub.c:3792 __slab_alloc_node mm/slub.c:3845 [inline] slab_alloc_node mm/slub.c:4025 [inline] __do_kmalloc_node mm/slub.c:4157 [inline] __kmalloc_noprof+0x257/0x400 mm/slub.c:4171 kmalloc_noprof include/linux/slab.h:664 [inline] load_elf_phdrs fs/binfmt_elf.c:526 [inline] load_elf_binary+0x2f1/0x2690 fs/binfmt_elf.c:855 search_binary_handler fs/exec.c:1799 [inline] exec_binprm fs/exec.c:1841 [inline] bprm_execve+0xaf8/0x1770 fs/exec.c:1892 do_execveat_common+0x553/0x700 fs/exec.c:1999 do_execve fs/exec.c:2073 [inline] __do_sys_execve fs/exec.c:2149 [inline] __se_sys_execve fs/exec.c:2144 [inline] __x64_sys_execve+0x92/0xb0 fs/exec.c:2144 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f page last free pid 4709 tgid 4709 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1093 [inline] free_unref_page+0xd22/0xea0 mm/page_alloc.c:2651 discard_slab mm/slub.c:2562 [inline] __put_partials+0xeb/0x130 mm/slub.c:3030 put_cpu_partial+0x17c/0x250 mm/slub.c:3105 __slab_free+0x2ea/0x3d0 mm/slub.c:4343 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x9e/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:322 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook mm/slub.c:3975 [inline] slab_alloc_node mm/slub.c:4037 [inline] kmem_cache_alloc_noprof+0x135/0x2a0 mm/slub.c:4044 getname_flags+0xb7/0x540 fs/namei.c:139 do_sys_openat2+0xd2/0x1d0 fs/open.c:1411 do_sys_open fs/open.c:1432 [inline] __do_sys_openat fs/open.c:1448 [inline] __se_sys_openat fs/open.c:1443 [inline] __x64_sys_openat+0x247/0x2a0 fs/open.c:1443 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff88802d75df00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88802d75df80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88802d75e000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88802d75e080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88802d75e100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================