truncated vhci_hcd: default hub control req: 40a1 vd3e0 i0041 l20845 loop3: p1 start 1 is beyond EOD, truncated loop3: p2 size 2 extends beyond EOD, truncated ================================================================== BUG: KASAN: use-after-free in __read_once_size include/linux/compiler.h:182 [inline] BUG: KASAN: use-after-free in task_is_descendant.part.3+0x610/0x670 security/yama/yama_lsm.c:295 Read of size 8 at addr ffff888182fecbe0 by task syz-executor0/8265 CPU: 1 PID: 8265 Comm: syz-executor0 Not tainted 4.20.0-rc6+ #154 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+0x244/0x39d lib/dump_stack.c:113 print_address_description.cold.7+0x9/0x1ff mm/kasan/report.c:256 kasan_report_error mm/kasan/report.c:354 [inline] kasan_report.cold.8+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:182 [inline] task_is_descendant.part.3+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:271 __ptrace_may_access+0x564/0x950 kernel/ptrace.c:331 ptrace_attach+0x1fa/0x640 kernel/ptrace.c:379 __do_sys_ptrace kernel/ptrace.c:1129 [inline] __se_sys_ptrace kernel/ptrace.c:1109 [inline] __x64_sys_ptrace+0x229/0x260 kernel/ptrace.c:1109 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x457669 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:00007f735103bc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000065 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000000457669 RDX: 0000000000000000 RSI: 0000000000001123 RDI: 0000000000004206 RBP: 000000000072bfa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f735103c6d4 R13: 00000000004c3a7f R14: 00000000004d6560 R15: 00000000ffffffff Allocated by task 6141: 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:158 [inline] dup_task_struct kernel/fork.c:843 [inline] copy_process+0x2026/0x87a0 kernel/fork.c:1751 _do_fork+0x1cb/0x11d0 kernel/fork.c:2216 __do_sys_clone kernel/fork.c:2323 [inline] __se_sys_clone kernel/fork.c:2317 [inline] __x64_sys_clone+0xbf/0x150 kernel/fork.c:2317 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 16: 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:3760 free_task_struct kernel/fork.c:163 [inline] free_task+0x16e/0x1f0 kernel/fork.c:457 __put_task_struct+0x2e6/0x620 kernel/fork.c:730 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:240 [inline] rcu_do_batch kernel/rcu/tree.c:2437 [inline] invoke_rcu_callbacks kernel/rcu/tree.c:2716 [inline] rcu_process_callbacks+0x100a/0x1ac0 kernel/rcu/tree.c:2697 __do_softirq+0x308/0xb7e kernel/softirq.c:292 The buggy address belongs to the object at ffff888182fec700 which belongs to the cache task_struct(17:syz0) of size 6080 The buggy address is located 1248 bytes inside of 6080-byte region [ffff888182fec700, ffff888182fedec0) The buggy address belongs to the page: page:ffffea00060bfb00 count:1 mapcount:0 mapping:ffff8881d8b6fb00 index:0x0 compound_mapcount: 0 flags: 0x2fffc0000010200(slab|head) raw: 02fffc0000010200 ffffea0005efe308 ffffea00060b3c88 ffff8881d8b6fb00 raw: 0000000000000000 ffff888182fec700 0000000100000001 ffff888181796440 page dumped because: kasan: bad access detected page->mem_cgroup:ffff888181796440 Memory state around the buggy address: ffff888182feca80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888182fecb00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888182fecb80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888182fecc00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888182fecc80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================