binder: 12719:12721 got transaction to context manager from process owning it binder: BINDER_SET_CONTEXT_MGR already set binder: 12719:12724 ioctl 40046207 0 returned -16 binder: 12719:12721 BC_ACQUIRE_DONE u0000000000000000 no match ================================================================== BUG: KASAN: use-after-free in __read_once_size include/linux/compiler.h:188 [inline] BUG: KASAN: use-after-free in task_is_descendant.part.2+0x610/0x670 security/yama/yama_lsm.c:295 Read of size 8 at addr ffff8801c4666b20 by task syz-executor3/12722 CPU: 1 PID: 12722 Comm: syz-executor3 Not tainted 4.19.0-rc8+ #70 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1c4/0x2b4 lib/dump_stack.c:113 print_address_description.cold.8+0x9/0x1ff mm/kasan/report.c:256 kasan_report_error mm/kasan/report.c:354 [inline] kasan_report.cold.9+0x242/0x309 mm/kasan/report.c:412 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:433 __read_once_size include/linux/compiler.h:188 [inline] task_is_descendant.part.2+0x610/0x670 security/yama/yama_lsm.c:295 task_is_descendant security/yama/yama_lsm.c:282 [inline] yama_ptrace_access_check+0x215/0x10fc security/yama/yama_lsm.c:371 security_ptrace_access_check+0x54/0xb0 security/security.c:260 __ptrace_may_access+0x564/0x950 kernel/ptrace.c:331 ptrace_attach+0x1fa/0x640 kernel/ptrace.c:379 __do_sys_ptrace kernel/ptrace.c:1130 [inline] __se_sys_ptrace kernel/ptrace.c:1110 [inline] __x64_sys_ptrace+0x229/0x260 kernel/ptrace.c:1110 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x457569 Code: fd b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 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 0f 83 cb b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f7df12c4c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000065 RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 0000000000457569 RDX: 0000000000000000 RSI: 0000000000000265 RDI: 0000000000000010 RBP: 000000000072bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f7df12c56d4 R13: 00000000004c30c5 R14: 00000000004d4ab8 R15: 00000000ffffffff Allocated by task 8920: save_stack+0x43/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] kasan_kmalloc+0xc7/0xe0 mm/kasan/kasan.c:553 kasan_slab_alloc+0x12/0x20 mm/kasan/kasan.c:490 kmem_cache_alloc_node+0x144/0x730 mm/slab.c:3644 alloc_task_struct_node kernel/fork.c:157 [inline] dup_task_struct kernel/fork.c:802 [inline] copy_process+0x1ff4/0x8780 kernel/fork.c:1707 _do_fork+0x1cb/0x11d0 kernel/fork.c:2166 __do_sys_clone kernel/fork.c:2273 [inline] __se_sys_clone kernel/fork.c:2267 [inline] __x64_sys_clone+0xbf/0x150 kernel/fork.c:2267 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 18: save_stack+0x43/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/kasan.c:521 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528 __cache_free mm/slab.c:3498 [inline] kmem_cache_free+0x83/0x290 mm/slab.c:3756 free_task_struct kernel/fork.c:162 [inline] free_task+0x16e/0x1f0 kernel/fork.c:416 __put_task_struct+0x2e6/0x620 kernel/fork.c:689 put_task_struct include/linux/sched/task.h:96 [inline] delayed_put_task_struct+0x2ff/0x4c0 kernel/exit.c:181 __rcu_reclaim kernel/rcu/rcu.h:236 [inline] rcu_do_batch kernel/rcu/tree.c:2576 [inline] invoke_rcu_callbacks kernel/rcu/tree.c:2880 [inline] __rcu_process_callbacks kernel/rcu/tree.c:2847 [inline] rcu_process_callbacks+0xf23/0x2670 kernel/rcu/tree.c:2864 __do_softirq+0x30b/0xad8 kernel/softirq.c:292 The buggy address belongs to the object at ffff8801c4666640 which belongs to the cache task_struct(65:syz3) of size 6080 The buggy address is located 1248 bytes inside of 6080-byte region [ffff8801c4666640, ffff8801c4667e00) The buggy address belongs to the page: page:ffffea0007119980 count:1 mapcount:0 mapping:ffff8801c2336800 index:0x0 compound_mapcount: 0 flags: 0x2fffc0000008100(slab|head) raw: 02fffc0000008100 ffffea00070a0008 ffffea0006080688 ffff8801c2336800 raw: 0000000000000000 ffff8801c4666640 0000000100000001 ffff8801bdb40c00 page dumped because: kasan: bad access detected page->mem_cgroup:ffff8801bdb40c00 Memory state around the buggy address: ffff8801c4666a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8801c4666a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8801c4666b00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8801c4666b80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8801c4666c00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================