================================================================== 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 ffff88019314b1d8 by task syz-executor5/4475 CPU: 1 PID: 4475 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: 0033:0x45416a Code: f7 d8 64 89 04 25 d4 02 00 00 64 4c 8b 0c 25 10 00 00 00 31 d2 4d 8d 91 d0 02 00 00 31 f6 bf 11 00 20 01 b8 38 00 00 00 0f 05 <48> 3d 00 f0 ff ff 0f 87 f5 00 00 00 85 c0 41 89 c5 0f 85 fc 00 00 RSP: 002b:00007ffeb8717f00 EFLAGS: 00000246 ORIG_RAX: 0000000000000038 RAX: 0000000000000275 RBX: 00007ffeb8717f00 RCX: 000000000045416a RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011 RBP: 00007ffeb8717f40 R08: 0000000000000001 R09: 0000000002731940 R10: 0000000002731c10 R11: 0000000000000246 R12: 0000000000000001 R13: 0000000000000000 R14: 0000000000000000 R15: 00000000007034c0 Allocated by task 11384: 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 24: 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 ffff88019314aa80 which belongs to the cache kmalloc-4096 of size 4096 The buggy address is located 1880 bytes inside of 4096-byte region [ffff88019314aa80, ffff88019314ba80) The buggy address belongs to the page: page:ffffea00064c5280 count:1 mapcount:0 mapping:ffff8801da800dc0 index:0x0 compound_mapcount: 0 flags: 0x2fffc0000008100(slab|head) raw: 02fffc0000008100 ffffea000759bd88 ffffea00068b7208 ffff8801da800dc0 raw: 0000000000000000 ffff88019314aa80 0000000100000001 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88019314b080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88019314b100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88019314b180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88019314b200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88019314b280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================