================================================================== binder: 18801:18812 transaction failed 29189/-22, size 0-0 line 2788 BUG: KASAN: use-after-free in __lock_acquire+0x3d4d/0x3e00 kernel/locking/lockdep.c:3310 Read of size 8 at addr ffff8801c719d870 by task syz-executor4/18810 CPU: 0 PID: 18810 Comm: syz-executor4 Not tainted 4.15.0+ #291 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x194/0x257 lib/dump_stack.c:53 print_address_description+0x73/0x250 mm/kasan/report.c:252 kasan_report_error mm/kasan/report.c:351 [inline] kasan_report+0x25b/0x340 mm/kasan/report.c:409 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:430 __lock_acquire+0x3d4d/0x3e00 kernel/locking/lockdep.c:3310 lock_acquire+0x1d5/0x580 kernel/locking/lockdep.c:3920 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x96/0xc0 kernel/locking/spinlock.c:152 remove_wait_queue+0x81/0x350 kernel/sched/wait.c:50 ep_remove_wait_queue fs/eventpoll.c:595 [inline] ep_unregister_pollwait.isra.7+0x18c/0x590 fs/eventpoll.c:613 ep_free+0x13f/0x320 fs/eventpoll.c:830 ep_eventpoll_release+0x44/0x60 fs/eventpoll.c:862 __fput+0x327/0x7e0 fs/file_table.c:209 ____fput+0x15/0x20 fs/file_table.c:243 task_work_run+0x199/0x270 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:191 [inline] exit_to_usermode_loop+0x275/0x2f0 arch/x86/entry/common.c:165 prepare_exit_to_usermode arch/x86/entry/common.c:195 [inline] syscall_return_slowpath+0x490/0x550 arch/x86/entry/common.c:264 entry_SYSCALL_64_fastpath+0x9e/0xa0 RIP: 0033:0x453299 RSP: 002b:00007f04f0b00c58 EFLAGS: 00000212 ORIG_RAX: 0000000000000124 RAX: 0000000000000016 RBX: 000000000071bea0 RCX: 0000000000453299 RDX: 0000000000000000 RSI: 0000000000000016 RDI: 0000000000000013 RBP: 000000000000006d R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000212 R12: 00000000006efad8 R13: 00000000ffffffff R14: 00007f04f0b016d4 R15: 0000000000000000 Allocated by task 18810: save_stack+0x43/0xd0 mm/kasan/kasan.c:447 set_track mm/kasan/kasan.c:459 [inline] kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:551 kmem_cache_alloc_trace+0x136/0x750 mm/slab.c:3606 kmalloc include/linux/slab.h:499 [inline] kzalloc include/linux/slab.h:688 [inline] binder_get_thread+0x1cf/0x870 drivers/android/binder.c:4219 binder_poll+0x8c/0x390 drivers/android/binder.c:4321 ep_item_poll.isra.10+0xf2/0x320 fs/eventpoll.c:885 ep_insert+0x6a2/0x1ac0 fs/eventpoll.c:1457 SYSC_epoll_ctl fs/eventpoll.c:2104 [inline] SyS_epoll_ctl+0x12bf/0x1a80 fs/eventpoll.c:1990 entry_SYSCALL_64_fastpath+0x29/0xa0 Freed by task 18810: save_stack+0x43/0xd0 mm/kasan/kasan.c:447 set_track mm/kasan/kasan.c:459 [inline] kasan_slab_free+0x71/0xc0 mm/kasan/kasan.c:524 __cache_free mm/slab.c:3484 [inline] kfree+0xd6/0x260 mm/slab.c:3799 binder_free_thread drivers/android/binder.c:4246 [inline] binder_thread_dec_tmpref+0x27f/0x310 drivers/android/binder.c:1821 binder_thread_release+0x27d/0x540 drivers/android/binder.c:4310 binder_ioctl+0xc02/0x1417 drivers/android/binder.c:4527 vfs_ioctl fs/ioctl.c:46 [inline] do_vfs_ioctl+0x1b1/0x1520 fs/ioctl.c:686 SYSC_ioctl fs/ioctl.c:701 [inline] SyS_ioctl+0x8f/0xc0 fs/ioctl.c:692 entry_SYSCALL_64_fastpath+0x29/0xa0 The buggy address belongs to the object at ffff8801c719d7c0 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 176 bytes inside of 512-byte region [ffff8801c719d7c0, ffff8801c719d9c0) The buggy address belongs to the page: page:ffffea00071c6740 count:1 mapcount:0 mapping:ffff8801c719d040 index:0xffff8801c719d2c0 flags: 0x2fffc0000000100(slab) raw: 02fffc0000000100 ffff8801c719d040 ffff8801c719d2c0 0000000100000002 raw: ffffea000730b620 ffffea0007548e20 ffff8801db000940 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8801c719d700: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff8801c719d780: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb >ffff8801c719d800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8801c719d880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8801c719d900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================