lowmemorykiller: Killing 'syz-executor.5' (4703) (tgid 4703), adj 1000, to free 51396kB on behalf of 'kswapd0' (33) because cache -4412140kB is below limit 6144kB for oom_score_adj 0 Free memory is -6664kB above reserved ================================================================== BUG: KASAN: use-after-free in __lock_acquire+0x2f37/0x4390 kernel/locking/lockdep.c:3224 Read of size 8 at addr ffff8801a02b4f18 by task kswapd0/33 CPU: 1 PID: 33 Comm: kswapd0 Not tainted 4.9.194+ #0 ffff8801d84074a0 ffffffff81b67001 0000000000000000 ffffea000680ac00 ffff8801a02b4f18 0000000000000008 ffffffff81210037 ffff8801d84074d8 ffffffff8150c4f1 0000000000000000 ffff8801a02b4f18 ffff8801a02b4f18 Call Trace: [<0000000051098d73>] __dump_stack lib/dump_stack.c:15 [inline] [<0000000051098d73>] dump_stack+0xc1/0x120 lib/dump_stack.c:51 [<00000000ce7e987d>] print_address_description+0x6f/0x23a mm/kasan/report.c:256 [<00000000ee05c854>] kasan_report_error mm/kasan/report.c:355 [inline] [<00000000ee05c854>] kasan_report mm/kasan/report.c:413 [inline] [<00000000ee05c854>] kasan_report.cold+0x8c/0x2ba mm/kasan/report.c:397 [<000000007ce1287c>] __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:434 [<000000004df38d1f>] __lock_acquire+0x2f37/0x4390 kernel/locking/lockdep.c:3224 [<00000000c8699b81>] lock_acquire+0x133/0x3d0 kernel/locking/lockdep.c:3756 [<00000000202ebbe3>] __raw_spin_lock include/linux/spinlock_api_smp.h:144 [inline] [<00000000202ebbe3>] _raw_spin_lock+0x38/0x50 kernel/locking/spinlock.c:151 [<0000000028485d99>] spin_lock include/linux/spinlock.h:302 [inline] [<0000000028485d99>] task_lock include/linux/sched.h:3217 [inline] [<0000000028485d99>] get_task_mm+0x20/0xc0 kernel/fork.c:1012 [<000000000fbfa4b8>] handle_lmk_event+0x84/0x920 drivers/staging/android/lowmemorykiller.c:109 [<00000000d2516692>] lowmem_scan+0x6f3/0xb70 drivers/staging/android/lowmemorykiller.c:354 [<000000006e79300c>] do_shrink_slab mm/vmscan.c:399 [inline] [<000000006e79300c>] shrink_slab.part.0+0x3cf/0xa20 mm/vmscan.c:502 [<00000000ccc737f7>] shrink_slab mm/vmscan.c:466 [inline] [<00000000ccc737f7>] shrink_node+0x1ed/0x750 mm/vmscan.c:2604 [<000000001caffda6>] kswapd_shrink_node mm/vmscan.c:3209 [inline] [<000000001caffda6>] balance_pgdat mm/vmscan.c:3329 [inline] [<000000001caffda6>] kswapd+0x7f8/0x13b0 mm/vmscan.c:3523 [<00000000c201c8b7>] kthread+0x278/0x310 kernel/kthread.c:211 [<00000000b8492ed8>] ret_from_fork+0x5c/0x70 arch/x86/entry/entry_64.S:375 Allocated by task 4680: save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:57 save_stack mm/kasan/kasan.c:512 [inline] set_track mm/kasan/kasan.c:524 [inline] kasan_kmalloc.part.0+0x62/0xf0 mm/kasan/kasan.c:616 kasan_kmalloc+0xb7/0xd0 mm/kasan/kasan.c:601 kasan_slab_alloc+0xf/0x20 mm/kasan/kasan.c:554 slab_post_alloc_hook mm/slab.h:417 [inline] slab_alloc_node mm/slub.c:2715 [inline] slab_alloc mm/slub.c:2723 [inline] kmem_cache_alloc+0xd5/0x2b0 mm/slub.c:2728 kmem_cache_alloc_node include/linux/slab.h:364 [inline] alloc_task_struct_node kernel/fork.c:146 [inline] dup_task_struct kernel/fork.c:490 [inline] copy_process.part.0+0x1714/0x6690 kernel/fork.c:1640 copy_process kernel/fork.c:1586 [inline] _do_fork+0x1c1/0xd50 kernel/fork.c:2111 SYSC_clone kernel/fork.c:2223 [inline] SyS_clone+0x37/0x50 kernel/fork.c:2217 do_syscall_64+0x1ad/0x5c0 arch/x86/entry/common.c:288 entry_SYSCALL_64_after_swapgs+0x5d/0xdb Freed by task 2110: save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:57 save_stack mm/kasan/kasan.c:512 [inline] set_track mm/kasan/kasan.c:524 [inline] kasan_slab_free+0xb0/0x190 mm/kasan/kasan.c:589 slab_free_hook mm/slub.c:1355 [inline] slab_free_freelist_hook mm/slub.c:1377 [inline] slab_free mm/slub.c:2958 [inline] kmem_cache_free+0xbe/0x310 mm/slub.c:2980 free_task_struct kernel/fork.c:151 [inline] free_task+0x74/0xb0 kernel/fork.c:367 __put_task_struct+0x27c/0x4a0 kernel/fork.c:404 put_task_struct include/linux/sched.h:2337 [inline] delayed_put_task_struct+0x9a/0x2f0 kernel/exit.c:166 __rcu_reclaim kernel/rcu/rcu.h:118 [inline] rcu_do_batch kernel/rcu/tree.c:2797 [inline] invoke_rcu_callbacks kernel/rcu/tree.c:3061 [inline] __rcu_process_callbacks kernel/rcu/tree.c:3028 [inline] rcu_process_callbacks+0x8c2/0x1300 kernel/rcu/tree.c:3045 __do_softirq+0x22d/0x964 kernel/softirq.c:288 The buggy address belongs to the object at ffff8801a02b4740 which belongs to the cache task_struct of size 5824 The buggy address is located 2008 bytes inside of 5824-byte region [ffff8801a02b4740, ffff8801a02b5e00) The buggy address belongs to the page: page:ffffea000680ac00 count:1 mapcount:0 mapping: (null) index:0x0 compound_mapcount: 0 flags: 0x4000000000010200(slab|head) page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8801a02b4e00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8801a02b4e80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8801a02b4f00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8801a02b4f80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8801a02b5000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================