================================================================== BUG: KASAN: use-after-free in __read_once_size include/linux/compiler.h:188 [inline] BUG: KASAN: use-after-free in list_empty include/linux/list.h:203 [inline] BUG: KASAN: use-after-free in shrink_slab_memcg mm/vmscan.c:595 [inline] BUG: KASAN: use-after-free in shrink_slab+0xa04/0xa60 mm/vmscan.c:671 Read of size 8 at addr ffff88019b666a58 by task syz-executor5/4415 CPU: 1 PID: 4415 Comm: syz-executor5 Not tainted 4.18.0-rc4-next-20180713+ #7 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+0x1c9/0x2b4 lib/dump_stack.c:113 print_address_description+0x6c/0x20b mm/kasan/report.c:256 kasan_report_error mm/kasan/report.c:354 [inline] kasan_report.cold.7+0x242/0x30d 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] list_empty include/linux/list.h:203 [inline] shrink_slab_memcg mm/vmscan.c:595 [inline] shrink_slab+0xa04/0xa60 mm/vmscan.c:671 shrink_node+0x429/0x16a0 mm/vmscan.c:2735 shrink_zones mm/vmscan.c:2964 [inline] do_try_to_free_pages+0x3e7/0x1290 mm/vmscan.c:3026 try_to_free_mem_cgroup_pages+0x49d/0xc90 mm/vmscan.c:3324 reclaim_high.constprop.73+0x137/0x1e0 mm/memcontrol.c:2060 mem_cgroup_handle_over_high+0x8d/0x130 mm/memcontrol.c:2085 tracehook_notify_resume include/linux/tracehook.h:195 [inline] exit_to_usermode_loop+0x287/0x380 arch/x86/entry/common.c:166 prepare_exit_to_usermode arch/x86/entry/common.c:197 [inline] syscall_return_slowpath arch/x86/entry/common.c:268 [inline] do_syscall_64+0x6be/0x820 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x4585e7 Code: 00 00 00 49 89 ca b8 36 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 da 8e fb ff c3 66 0f 1f 84 00 00 00 00 00 b8 29 00 00 00 0f 05 <48> 3d 01 f0 ff ff 0f 83 bd 8e fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007ffe5a5c8b78 EFLAGS: 00000246 ORIG_RAX: 0000000000000029 RAX: 0000000000000013 RBX: 000000000000000a RCX: 00000000004585e7 RDX: 0000000000000006 RSI: 0000000000000001 RDI: 000000000000000a RBP: 0000000000705d60 R08: 0000000000006000 R09: 0000000000004000 R10: 00007ffe5a5c8ca0 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000001380 R14: 0000000000000029 R15: 0000000000703ba0 Allocated by task 14243: save_stack+0x43/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] kasan_kmalloc+0xc4/0xe0 mm/kasan/kasan.c:553 kmem_cache_alloc_trace+0x152/0x780 mm/slab.c:3620 kmalloc include/linux/slab.h:513 [inline] kzalloc include/linux/slab.h:707 [inline] alloc_super+0xd4/0xb10 fs/super.c:199 sget_fc+0x269/0x950 fs/super.c:533 vfs_get_super+0x6e/0x270 fs/super.c:1255 proc_get_tree+0x88/0xb0 fs/proc/root.c:159 vfs_get_tree+0x1cb/0x5c0 fs/super.c:1743 do_new_mount fs/namespace.c:2567 [inline] do_mount+0x6c1/0x1fb0 fs/namespace.c:2889 ksys_mount+0x12d/0x140 fs/namespace.c:3105 __do_sys_mount fs/namespace.c:3119 [inline] __se_sys_mount fs/namespace.c:3116 [inline] __x64_sys_mount+0xbe/0x150 fs/namespace.c:3116 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 4686: save_stack+0x43/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] __kasan_slab_free+0x11a/0x170 mm/kasan/kasan.c:521 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528 __cache_free mm/slab.c:3498 [inline] kfree+0xd9/0x260 mm/slab.c:3813 destroy_super_work+0x40/0x50 fs/super.c:164 process_one_work+0xc73/0x1ba0 kernel/workqueue.c:2153 worker_thread+0x189/0x13c0 kernel/workqueue.c:2296 kthread+0x345/0x410 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:415 The buggy address belongs to the object at ffff88019b666300 which belongs to the cache kmalloc-4096 of size 4096 The buggy address is located 1880 bytes inside of 4096-byte region [ffff88019b666300, ffff88019b667300) The buggy address belongs to the page: page:ffffea00066d9980 count:1 mapcount:0 mapping:ffff8801da800dc0 index:0x0 compound_mapcount: 0 flags: 0x2fffc0000008100(slab|head) raw: 02fffc0000008100 ffffea00075f2f88 ffffea00063fea08 ffff8801da800dc0 raw: 0000000000000000 ffff88019b666300 0000000100000001 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88019b666900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88019b666980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88019b666a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88019b666a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88019b666b00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================