================================================================== BUG: KASAN: slab-use-after-free in __lock_acquire+0x2d85/0x3b20 kernel/locking/lockdep.c:5005 Read of size 8 at addr ffff8880223c09f8 by task syz-executor.1/7482 CPU: 0 PID: 7482 Comm: syz-executor.1 Not tainted 6.7.0-rc8-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023 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 __lock_acquire+0x2d85/0x3b20 kernel/locking/lockdep.c:5005 lock_acquire kernel/locking/lockdep.c:5754 [inline] lock_acquire+0x1ae/0x520 kernel/locking/lockdep.c:5719 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3a/0x50 kernel/locking/spinlock.c:162 class_raw_spinlock_irqsave_constructor include/linux/spinlock.h:518 [inline] try_to_wake_up+0xb0/0x13d0 kernel/sched/core.c:4226 call_timer_fn+0x193/0x590 kernel/time/timer.c:1700 expire_timers kernel/time/timer.c:1751 [inline] __run_timers+0x764/0xb20 kernel/time/timer.c:2022 run_timer_softirq+0x58/0xd0 kernel/time/timer.c:2035 __do_softirq+0x21a/0x8de kernel/softirq.c:553 invoke_softirq kernel/softirq.c:427 [inline] __irq_exit_rcu kernel/softirq.c:632 [inline] irq_exit_rcu+0xb7/0x120 kernel/softirq.c:644 sysvec_apic_timer_interrupt+0x95/0xb0 arch/x86/kernel/apic/apic.c:1076 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:649 RIP: 0010:lock_acquire+0x1ef/0x520 kernel/locking/lockdep.c:5722 Code: c1 05 3d 84 9a 7e 83 f8 01 0f 85 b4 02 00 00 9c 58 f6 c4 02 0f 85 9f 02 00 00 48 85 ed 74 01 fb 48 b8 00 00 00 00 00 fc ff df <48> 01 c3 48 c7 03 00 00 00 00 48 c7 43 08 00 00 00 00 48 8b 84 24 RSP: 0018:ffffc90002d5fbb0 EFLAGS: 00000206 RAX: dffffc0000000000 RBX: 1ffff920005abf78 RCX: ffffffff8167148e RDX: 0000000000000001 RSI: ffffffff8accb1a0 RDI: ffffffff8b2efce0 RBP: 0000000000000200 R08: 0000000000000000 R09: fffffbfff23e37d6 R10: ffffffff91f1beb7 R11: 0000000000000000 R12: 0000000000000001 R13: 0000000000000000 R14: ffff88802a1c27a0 R15: 0000000000000000 __might_fault mm/memory.c:5956 [inline] __might_fault+0x11f/0x1a0 mm/memory.c:5949 do_recvmmsg+0x2dc/0x740 net/socket.c:2945 __sys_recvmmsg net/socket.c:3018 [inline] __do_sys_recvmmsg net/socket.c:3041 [inline] __se_sys_recvmmsg net/socket.c:3034 [inline] __x64_sys_recvmmsg+0x235/0x290 net/socket.c:3034 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0x40/0x110 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x63/0x6b RIP: 0033:0x7f5e5947cce9 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:00007f5e5a1ef0c8 EFLAGS: 00000246 ORIG_RAX: 000000000000012b RAX: ffffffffffffffda RBX: 00007f5e5959c050 RCX: 00007f5e5947cce9 RDX: 00000000040002db RSI: 0000000020000740 RDI: 0000000000000003 RBP: 00007f5e594c947a R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000006e R14: 00007f5e5959c050 R15: 00007ffef84b8388 Allocated by task 2: 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:188 [inline] slab_post_alloc_hook mm/slab.h:763 [inline] slab_alloc_node mm/slub.c:3478 [inline] kmem_cache_alloc_node+0x180/0x330 mm/slub.c:3523 alloc_task_struct_node kernel/fork.c:173 [inline] dup_task_struct kernel/fork.c:1110 [inline] copy_process+0x41c/0x73f0 kernel/fork.c:2332 kernel_clone+0xfd/0x930 kernel/fork.c:2907 kernel_thread+0xc0/0x100 kernel/fork.c:2969 create_kthread kernel/kthread.c:411 [inline] kthreadd+0x4fb/0x7d0 kernel/kthread.c:764 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242 Freed by task 7465: 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:164 [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+0xf8/0x350 mm/slub.c:3831 put_task_struct include/linux/sched/task.h:136 [inline] put_task_struct include/linux/sched/task.h:123 [inline] delayed_put_task_struct+0x21b/0x2c0 kernel/exit.c:227 rcu_do_batch kernel/rcu/tree.c:2158 [inline] rcu_core+0x819/0x1680 kernel/rcu/tree.c:2431 __do_softirq+0x21a/0x8de kernel/softirq.c:553 Last potentially related work creation: kasan_save_stack+0x33/0x50 mm/kasan/common.c:45 __kasan_record_aux_stack+0xbc/0xd0 mm/kasan/generic.c:492 __call_rcu_common.constprop.0+0x9a/0x7a0 kernel/rcu/tree.c:2681 put_task_struct_rcu_user kernel/exit.c:233 [inline] put_task_struct_rcu_user+0x87/0xc0 kernel/exit.c:230 context_switch kernel/sched/core.c:5379 [inline] __schedule+0xee3/0x5af0 kernel/sched/core.c:6688 __schedule_loop kernel/sched/core.c:6763 [inline] schedule+0xe9/0x270 kernel/sched/core.c:6778 schedule_timeout+0x257/0x290 kernel/time/timer.c:2143 unix_wait_for_peer+0x24d/0x280 net/unix/af_unix.c:1474 unix_dgram_sendmsg+0x19eb/0x1ca0 net/unix/af_unix.c:2078 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0xd5/0x180 net/socket.c:745 ____sys_sendmsg+0x2ac/0x940 net/socket.c:2584 ___sys_sendmsg+0x135/0x1d0 net/socket.c:2638 __sys_sendmmsg+0x1a1/0x450 net/socket.c:2724 __do_sys_sendmmsg net/socket.c:2753 [inline] __se_sys_sendmmsg net/socket.c:2750 [inline] __x64_sys_sendmmsg+0x9c/0x100 net/socket.c:2750 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0x40/0x110 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x63/0x6b Second to last potentially related work creation: kasan_save_stack+0x33/0x50 mm/kasan/common.c:45 __kasan_record_aux_stack+0xbc/0xd0 mm/kasan/generic.c:492 __call_rcu_common.constprop.0+0x9a/0x7a0 kernel/rcu/tree.c:2681 put_task_struct_rcu_user kernel/exit.c:233 [inline] put_task_struct_rcu_user+0x87/0xc0 kernel/exit.c:230 release_task+0xe7d/0x1b10 kernel/exit.c:283 wait_task_zombie kernel/exit.c:1184 [inline] wait_consider_task+0x17c4/0x40a0 kernel/exit.c:1411 do_wait_thread kernel/exit.c:1474 [inline] __do_wait+0x1e3/0x890 kernel/exit.c:1592 do_wait+0x212/0x530 kernel/exit.c:1626 kernel_wait4+0x16d/0x280 kernel/exit.c:1785 __do_sys_wait4+0x15b/0x170 kernel/exit.c:1813 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0x40/0x110 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x63/0x6b The buggy address belongs to the object at ffff8880223c0000 which belongs to the cache task_struct of size 7360 The buggy address is located 2552 bytes inside of freed 7360-byte region [ffff8880223c0000, ffff8880223c1cc0) The buggy address belongs to the physical page: page:ffffea000088f000 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x223c0 head:ffffea000088f000 order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0 memcg:ffff88807f343a81 flags: 0xfff00000000840(slab|head|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000840 ffff888015251500 dead000000000100 dead000000000122 raw: 0000000000000000 0000000000040004 00000001ffffffff ffff88807f343a81 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 1084, tgid 1084 (kworker/u4:6), ts 8627071630, free_ts 0 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x2d0/0x350 mm/page_alloc.c:1537 prep_new_page mm/page_alloc.c:1544 [inline] get_page_from_freelist+0xa25/0x36d0 mm/page_alloc.c:3312 __alloc_pages+0x22e/0x2420 mm/page_alloc.c:4568 alloc_pages_mpol+0x258/0x5f0 mm/mempolicy.c:2133 alloc_slab_page mm/slub.c:1870 [inline] allocate_slab mm/slub.c:2017 [inline] new_slab+0x283/0x3c0 mm/slub.c:2070 ___slab_alloc+0x979/0x1500 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] kmem_cache_alloc_node+0x132/0x330 mm/slub.c:3523 alloc_task_struct_node kernel/fork.c:173 [inline] dup_task_struct kernel/fork.c:1110 [inline] copy_process+0x41c/0x73f0 kernel/fork.c:2332 kernel_clone+0xfd/0x930 kernel/fork.c:2907 user_mode_thread+0xb4/0xf0 kernel/fork.c:2985 call_usermodehelper_exec_work kernel/umh.c:172 [inline] call_usermodehelper_exec_work+0xcb/0x170 kernel/umh.c:158 process_one_work+0x886/0x15d0 kernel/workqueue.c:2627 process_scheduled_works kernel/workqueue.c:2700 [inline] worker_thread+0x8b9/0x1290 kernel/workqueue.c:2781 kthread+0x2c6/0x3a0 kernel/kthread.c:388 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 page_owner free stack trace missing Memory state around the buggy address: ffff8880223c0880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880223c0900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8880223c0980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880223c0a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880223c0a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess): 0: c1 05 3d 84 9a 7e 83 roll $0x83,0x7e9a843d(%rip) # 0x7e9a8444 7: f8 clc 8: 01 0f add %ecx,(%rdi) a: 85 b4 02 00 00 9c 58 test %esi,0x589c0000(%rdx,%rax,1) 11: f6 c4 02 test $0x2,%ah 14: 0f 85 9f 02 00 00 jne 0x2b9 1a: 48 85 ed test %rbp,%rbp 1d: 74 01 je 0x20 1f: fb sti 20: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax 27: fc ff df * 2a: 48 01 c3 add %rax,%rbx <-- trapping instruction 2d: 48 c7 03 00 00 00 00 movq $0x0,(%rbx) 34: 48 c7 43 08 00 00 00 movq $0x0,0x8(%rbx) 3b: 00 3c: 48 rex.W 3d: 8b .byte 0x8b 3e: 84 .byte 0x84 3f: 24 .byte 0x24