RDX: 00000000004c2279 RSI: 0000000020000000 RDI: 00000000004de485 RBP: 0000000000000002 R08: 00007fc2bf474820 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000020000000 R14: 0000000000000000 R15: 0000000000000000 ================================================================== BUG: KASAN: use-after-free in __lock_acquire+0x3888/0x5140 kernel/locking/lockdep.c:3310 Read of size 8 at addr ffff8801cf595948 by task syz-executor7/22823 CPU: 0 PID: 22823 Comm: syz-executor7 Not tainted 4.17.0-rc7+ #79 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+0x1b9/0x294 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+0x242/0x2fe mm/kasan/report.c:412 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:433 __lock_acquire+0x3888/0x5140 kernel/locking/lockdep.c:3310 lock_acquire+0x1dc/0x520 kernel/locking/lockdep.c:3920 down_write+0x87/0x120 kernel/locking/rwsem.c:70 fuse_kill_sb_anon+0x50/0xb0 fs/fuse/inode.c:1200 deactivate_locked_super+0x97/0x100 fs/super.c:326 mount_nodev+0xfa/0x110 fs/super.c:1222 fuse_mount+0x2c/0x40 fs/fuse/inode.c:1192 mount_fs+0xae/0x328 fs/super.c:1277 vfs_kern_mount.part.34+0xd4/0x4d0 fs/namespace.c:1037 vfs_kern_mount fs/namespace.c:1027 [inline] do_new_mount fs/namespace.c:2518 [inline] do_mount+0x564/0x3070 fs/namespace.c:2848 ksys_mount+0x12d/0x140 fs/namespace.c:3064 __do_sys_mount fs/namespace.c:3078 [inline] __se_sys_mount fs/namespace.c:3075 [inline] __x64_sys_mount+0xbe/0x150 fs/namespace.c:3075 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x455a09 RSP: 002b:00007fc2bf474808 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 0000000000000016 RCX: 0000000000455a09 RDX: 00000000004c2279 RSI: 0000000020000000 RDI: 00000000004de485 RBP: 0000000000000002 R08: 00007fc2bf474820 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000020000000 R14: 0000000000000000 R15: 0000000000000000 Allocated by task 22823: 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:512 [inline] fuse_fill_super+0xc92/0x1e20 fs/fuse/inode.c:1096 mount_nodev+0x6b/0x110 fs/super.c:1220 fuse_mount+0x2c/0x40 fs/fuse/inode.c:1192 mount_fs+0xae/0x328 fs/super.c:1277 vfs_kern_mount.part.34+0xd4/0x4d0 fs/namespace.c:1037 vfs_kern_mount fs/namespace.c:1027 [inline] do_new_mount fs/namespace.c:2518 [inline] do_mount+0x564/0x3070 fs/namespace.c:2848 ksys_mount+0x12d/0x140 fs/namespace.c:3064 __do_sys_mount fs/namespace.c:3078 [inline] __se_sys_mount fs/namespace.c:3075 [inline] __x64_sys_mount+0xbe/0x150 fs/namespace.c:3075 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 22825: 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 __rcu_reclaim kernel/rcu/rcu.h:173 [inline] rcu_do_batch kernel/rcu/tree.c:2675 [inline] invoke_rcu_callbacks kernel/rcu/tree.c:2930 [inline] __rcu_process_callbacks kernel/rcu/tree.c:2897 [inline] rcu_process_callbacks+0xa69/0x15f0 kernel/rcu/tree.c:2914 __do_softirq+0x2e0/0xaf5 kernel/softirq.c:285 The buggy address belongs to the object at ffff8801cf595680 which belongs to the cache kmalloc-1024 of size 1024 The buggy address is located 712 bytes inside of 1024-byte region [ffff8801cf595680, ffff8801cf595a80) The buggy address belongs to the page: page:ffffea00073d6500 count:1 mapcount:0 mapping:ffff8801cf594000 index:0x0 compound_mapcount: 0 flags: 0x2fffc0000008100(slab|head) raw: 02fffc0000008100 ffff8801cf594000 0000000000000000 0000000100000007 raw: ffffea00075bf6a0 ffffea000607dca0 ffff8801da800ac0 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8801cf595800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8801cf595880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8801cf595900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8801cf595980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8801cf595a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================