KASAN: use-after-free Write in l2tp_session

Kernel	Title	Repro	Cause bisect	Count	Last	Reported	Patched	Status
android-5-10	KASAN: use-after-free Write in l2tp_session_delete			2	30d	54d	0/2	premoderation: reported on 2024/09/28 01:24
android-5-15	KASAN: use-after-free Write in l2tp_session_delete			2	147d	160d	0/2	auto-obsoleted due to no activity on 2024/09/25 05:09
android-5-15	KASAN: use-after-free Write in l2tp_session_delete (2)			2	1d12h	6d22h	0/2	premoderation: reported on 2024/11/14 20:24
linux-5.15	KASAN: use-after-free Write in l2tp_session_delete			2	479d	568d	0/3	auto-obsoleted due to no activity on 2023/11/08 00:22
linux-5.15	KASAN: use-after-free Write in l2tp_session_delete (2)			1	62d	62d	0/3	upstream: reported on 2024/09/19 22:43
android-6-1	KASAN: use-after-free Write in l2tp_session_delete	syz		4	10d	44d	0/2	premoderation: reported syz repro on 2024/10/08 10:15
upstream	KASAN: slab-use-after-free Write in l2tp_session_delete net	C	done	1286	129d	149d	27/28	fixed on 2024/08/14 03:44

================================================================== BUG: KASAN: use-after-free in instrument_atomic_read_write include/linux/instrumented.h:102 [inline] BUG: KASAN: use-after-free in test_and_set_bit include/asm-generic/bitops/instrumented-atomic.h:71 [inline] BUG: KASAN: use-after-free in l2tp_session_delete+0x21/0x600 net/l2tp/l2tp_core.c:1561 Write of size 8 at addr ffff88805b7b7808 by task kworker/u4:2/33 CPU: 0 PID: 33 Comm: kworker/u4:2 Not tainted 6.1.111-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 Workqueue: l2tp l2tp_tunnel_del_work Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106 print_address_description mm/kasan/report.c:284 [inline] print_report+0x15f/0x4f0 mm/kasan/report.c:395 kasan_report+0x136/0x160 mm/kasan/report.c:495 kasan_check_range+0x27f/0x290 mm/kasan/generic.c:189 instrument_atomic_read_write include/linux/instrumented.h:102 [inline] test_and_set_bit include/asm-generic/bitops/instrumented-atomic.h:71 [inline] l2tp_session_delete+0x21/0x600 net/l2tp/l2tp_core.c:1561 l2tp_tunnel_closeall net/l2tp/l2tp_core.c:1216 [inline] l2tp_tunnel_del_work+0x1ee/0x3b0 net/l2tp/l2tp_core.c:1256 process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292 worker_thread+0xa47/0x1200 kernel/workqueue.c:2439 kthread+0x28d/0x320 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 </TASK> Allocated by task 4161: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:52 ____kasan_kmalloc mm/kasan/common.c:374 [inline] __kasan_kmalloc+0x97/0xb0 mm/kasan/common.c:383 kasan_kmalloc include/linux/kasan.h:211 [inline] __do_kmalloc_node mm/slab_common.c:936 [inline] __kmalloc+0xb2/0x230 mm/slab_common.c:949 kmalloc include/linux/slab.h:562 [inline] kzalloc include/linux/slab.h:693 [inline] l2tp_session_create+0x37/0xb30 net/l2tp/l2tp_core.c:1597 pppol2tp_connect+0xc3d/0x1720 net/l2tp/l2tp_ppp.c:781 __sys_connect_file net/socket.c:2006 [inline] __sys_connect+0x2c9/0x300 net/socket.c:2023 __do_sys_connect net/socket.c:2033 [inline] __se_sys_connect net/socket.c:2030 [inline] __x64_sys_connect+0x76/0x80 net/socket.c:2030 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Freed by task 4175: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:52 kasan_save_free_info+0x27/0x40 mm/kasan/generic.c:516 ____kasan_slab_free+0xd6/0x120 mm/kasan/common.c:236 kasan_slab_free include/linux/kasan.h:177 [inline] slab_free_hook mm/slub.c:1724 [inline] slab_free_freelist_hook mm/slub.c:1750 [inline] slab_free mm/slub.c:3661 [inline] __kmem_cache_free+0x25c/0x3c0 mm/slub.c:3674 __sk_destruct+0x50/0x5f0 net/core/sock.c:2139 rcu_do_batch kernel/rcu/tree.c:2297 [inline] rcu_core+0xade/0x1820 kernel/rcu/tree.c:2557 handle_softirqs+0x2ee/0xa40 kernel/softirq.c:571 __do_softirq kernel/softirq.c:605 [inline] invoke_softirq kernel/softirq.c:445 [inline] __irq_exit_rcu+0x157/0x240 kernel/softirq.c:654 irq_exit_rcu+0x5/0x20 kernel/softirq.c:666 sysvec_apic_timer_interrupt+0x91/0xb0 arch/x86/kernel/apic/apic.c:1106 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:653 Last potentially related work creation: kasan_save_stack+0x3b/0x60 mm/kasan/common.c:45 __kasan_record_aux_stack+0xb0/0xc0 mm/kasan/generic.c:486 call_rcu+0x163/0xa10 kernel/rcu/tree.c:2845 pppol2tp_release+0x247/0x340 net/l2tp/l2tp_ppp.c:457 __sock_release net/socket.c:654 [inline] sock_close+0xcd/0x230 net/socket.c:1400 __fput+0x3f6/0x8d0 fs/file_table.c:320 task_work_run+0x246/0x300 kernel/task_work.c:203 exit_task_work include/linux/task_work.h:39 [inline] do_exit+0xa73/0x26a0 kernel/exit.c:871 do_group_exit+0x202/0x2b0 kernel/exit.c:1021 get_signal+0x16f7/0x17d0 kernel/signal.c:2870 arch_do_signal_or_restart+0xb0/0x1a10 arch/x86/kernel/signal.c:871 exit_to_user_mode_loop+0x6a/0x100 kernel/entry/common.c:174 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline] syscall_exit_to_user_mode+0x60/0x270 kernel/entry/common.c:303 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:87 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Second to last potentially related work creation: kasan_save_stack+0x3b/0x60 mm/kasan/common.c:45 __kasan_record_aux_stack+0xb0/0xc0 mm/kasan/generic.c:486 call_rcu+0x163/0xa10 kernel/rcu/tree.c:2845 qdisc_put net/sched/sch_generic.c:1095 [inline] dev_shutdown+0x359/0x440 net/sched/sch_generic.c:1483 unregister_netdevice_many+0xaac/0x17a0 net/core/dev.c:10873 ip6gre_exit_batch_net+0x415/0x460 net/ipv6/ip6_gre.c:1669 ops_exit_list net/core/net_namespace.c:177 [inline] cleanup_net+0x763/0xb60 net/core/net_namespace.c:604 process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292 worker_thread+0xa47/0x1200 kernel/workqueue.c:2439 kthread+0x28d/0x320 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 The buggy address belongs to the object at ffff88805b7b7800 which belongs to the cache kmalloc-1k of size 1024 The buggy address is located 8 bytes inside of 1024-byte region [ffff88805b7b7800, ffff88805b7b7c00) The buggy address belongs to the physical page: page:ffffea00016dec00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x5b7b0 head:ffffea00016dec00 order:3 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 0000000000000000 dead000000000001 ffff888017c41dc0 raw: 0000000000000000 0000000000100010 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 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 3641, tgid 3641 (syz-executor), ts 72120467541, free_ts 18303717872 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x18d/0x1b0 mm/page_alloc.c:2517 prep_new_page mm/page_alloc.c:2524 [inline] get_page_from_freelist+0x322e/0x33b0 mm/page_alloc.c:4290 __alloc_pages+0x28d/0x770 mm/page_alloc.c:5558 alloc_slab_page+0x6a/0x150 mm/slub.c:1794 allocate_slab mm/slub.c:1939 [inline] new_slab+0x84/0x2d0 mm/slub.c:1992 ___slab_alloc+0xc20/0x1270 mm/slub.c:3180 __slab_alloc mm/slub.c:3279 [inline] slab_alloc_node mm/slub.c:3364 [inline] __kmem_cache_alloc_node+0x19f/0x260 mm/slub.c:3437 __do_kmalloc_node mm/slab_common.c:935 [inline] __kmalloc_node_track_caller+0xa0/0x220 mm/slab_common.c:956 kmalloc_reserve net/core/skbuff.c:446 [inline] __alloc_skb+0x135/0x670 net/core/skbuff.c:515 alloc_skb include/linux/skbuff.h:1271 [inline] nlmsg_new include/net/netlink.h:991 [inline] rtmsg_fib+0x140/0x620 net/ipv4/fib_semantics.c:522 fib_table_insert+0xfb6/0x1f20 net/ipv4/fib_trie.c:1404 fib_magic net/ipv4/fib_frontend.c:1104 [inline] fib_add_ifaddr+0xf4c/0x1730 net/ipv4/fib_frontend.c:1148 fib_netdev_event+0x620/0x730 net/ipv4/fib_frontend.c:1486 notifier_call_chain kernel/notifier.c:87 [inline] raw_notifier_call_chain+0xd0/0x170 kernel/notifier.c:455 __dev_notify_flags+0x304/0x610 dev_change_flags+0xe7/0x190 net/core/dev.c:8661 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1444 [inline] free_pcp_prepare mm/page_alloc.c:1494 [inline] free_unref_page_prepare+0xf63/0x1120 mm/page_alloc.c:3369 free_unref_page+0x33/0x3e0 mm/page_alloc.c:3464 free_contig_range+0x9a/0x150 mm/page_alloc.c:9518 destroy_args+0xfe/0x997 mm/debug_vm_pgtable.c:1031 debug_vm_pgtable+0x416/0x46b mm/debug_vm_pgtable.c:1354 do_one_initcall+0x265/0x8f0 init/main.c:1298 do_initcall_level+0x157/0x207 init/main.c:1371 do_initcalls+0x49/0x86 init/main.c:1387 kernel_init_freeable+0x45c/0x60f init/main.c:1626 kernel_init+0x19/0x290 init/main.c:1514 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Memory state around the buggy address: ffff88805b7b7700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88805b7b7780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88805b7b7800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88805b7b7880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88805b7b7900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================

Crashes (2):
Time	Kernel	Commit	Syzkaller	Config	Log	Report	Syz repro	C repro	VM info	Assets (help?)	Manager	Title
2024/09/20 03:39	linux-6.1.y	e526b12bf916	6f888b75	.config	console log	report			info	[disk image] [vmlinux] [kernel image]	ci2-linux-6-1-kasan	KASAN: use-after-free Write in l2tp_session_delete
2024/08/29 01:01	linux-6.1.y	ee5e09825b81	ef3de9e8	.config	console log	report			info	[disk image] [vmlinux] [kernel image]	ci2-linux-6-1-kasan	KASAN: use-after-free Write in l2tp_session_delete

Crashes (2):

Assets (help?)