ptrace attach of "/root/syz-executor.3"[12471] was attempted by "/root/syz-executor.3"[12472] ================================================================== BUG: KASAN: use-after-free in free_fs_info fs/btrfs/ctree.h:2959 [inline] BUG: KASAN: use-after-free in btrfs_mount+0x2a45/0x2b28 fs/btrfs/super.c:1644 Read of size 8 at addr ffff88805696ac90 by task syz-executor.0/12447 CPU: 1 PID: 12447 Comm: syz-executor.0 Not tainted 4.14.148 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x138/0x197 lib/dump_stack.c:53 print_address_description.cold+0x7c/0x1dc mm/kasan/report.c:252 kasan_report_error mm/kasan/report.c:351 [inline] kasan_report mm/kasan/report.c:409 [inline] kasan_report.cold+0xa9/0x2af mm/kasan/report.c:393 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:430 free_fs_info fs/btrfs/ctree.h:2959 [inline] btrfs_mount+0x2a45/0x2b28 fs/btrfs/super.c:1644 mount_fs+0x97/0x2a1 fs/super.c:1237 vfs_kern_mount.part.0+0x5e/0x3d0 fs/namespace.c:1046 vfs_kern_mount+0x40/0x60 fs/namespace.c:1036 mount_subvol fs/btrfs/super.c:1392 [inline] btrfs_mount+0x3ce/0x2b28 fs/btrfs/super.c:1563 mount_fs+0x97/0x2a1 fs/super.c:1237 vfs_kern_mount.part.0+0x5e/0x3d0 fs/namespace.c:1046 vfs_kern_mount fs/namespace.c:1036 [inline] do_new_mount fs/namespace.c:2549 [inline] do_mount+0x417/0x27d0 fs/namespace.c:2879 SYSC_mount fs/namespace.c:3095 [inline] SyS_mount+0xab/0x120 fs/namespace.c:3072 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x45c4aa RSP: 002b:00007f5bea504a88 EFLAGS: 00000206 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007f5bea504b40 RCX: 000000000045c4aa RDX: 00007f5bea504ae0 RSI: 0000000020000080 RDI: 00007f5bea504b00 RBP: 0000000000000001 R08: 00007f5bea504b40 R09: 00007f5bea504ae0 R10: 0000000000000009 R11: 0000000000000206 R12: 0000000000000004 R13: 00000000004c8da6 R14: 00000000004e0200 R15: 0000000000000003 Allocated by task 12447: save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59 save_stack+0x45/0xd0 mm/kasan/kasan.c:447 set_track mm/kasan/kasan.c:459 [inline] kasan_kmalloc mm/kasan/kasan.c:551 [inline] kasan_kmalloc+0xce/0xf0 mm/kasan/kasan.c:529 __do_kmalloc_node mm/slab.c:3682 [inline] __kmalloc_node+0x51/0x80 mm/slab.c:3689 kmalloc_node include/linux/slab.h:530 [inline] kvmalloc_node+0x93/0xe0 mm/util.c:397 kvmalloc include/linux/mm.h:531 [inline] kvzalloc include/linux/mm.h:539 [inline] btrfs_mount+0xf88/0x2b28 fs/btrfs/super.c:1584 mount_fs+0x97/0x2a1 fs/super.c:1237 vfs_kern_mount.part.0+0x5e/0x3d0 fs/namespace.c:1046 vfs_kern_mount+0x40/0x60 fs/namespace.c:1036 mount_subvol fs/btrfs/super.c:1392 [inline] btrfs_mount+0x3ce/0x2b28 fs/btrfs/super.c:1563 mount_fs+0x97/0x2a1 fs/super.c:1237 vfs_kern_mount.part.0+0x5e/0x3d0 fs/namespace.c:1046 vfs_kern_mount fs/namespace.c:1036 [inline] do_new_mount fs/namespace.c:2549 [inline] do_mount+0x417/0x27d0 fs/namespace.c:2879 SYSC_mount fs/namespace.c:3095 [inline] SyS_mount+0xab/0x120 fs/namespace.c:3072 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 Freed by task 12447: save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59 save_stack+0x45/0xd0 mm/kasan/kasan.c:447 set_track mm/kasan/kasan.c:459 [inline] kasan_slab_free+0x75/0xc0 mm/kasan/kasan.c:524 __cache_free mm/slab.c:3496 [inline] kfree+0xcc/0x270 mm/slab.c:3815 kvfree+0x4d/0x60 mm/util.c:416 free_fs_info fs/btrfs/ctree.h:2972 [inline] btrfs_kill_super+0x421/0x540 fs/btrfs/super.c:2140 deactivate_locked_super+0x74/0xe0 fs/super.c:319 sget_userns+0x9d9/0xc30 fs/super.c:537 sget+0xd6/0x120 fs/super.c:572 btrfs_mount+0x1274/0x2b28 fs/btrfs/super.c:1610 mount_fs+0x97/0x2a1 fs/super.c:1237 vfs_kern_mount.part.0+0x5e/0x3d0 fs/namespace.c:1046 vfs_kern_mount+0x40/0x60 fs/namespace.c:1036 mount_subvol fs/btrfs/super.c:1392 [inline] btrfs_mount+0x3ce/0x2b28 fs/btrfs/super.c:1563 mount_fs+0x97/0x2a1 fs/super.c:1237 vfs_kern_mount.part.0+0x5e/0x3d0 fs/namespace.c:1046 vfs_kern_mount fs/namespace.c:1036 [inline] do_new_mount fs/namespace.c:2549 [inline] do_mount+0x417/0x27d0 fs/namespace.c:2879 SYSC_mount fs/namespace.c:3095 [inline] SyS_mount+0xab/0x120 fs/namespace.c:3072 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 The buggy address belongs to the object at ffff8880569693c0 which belongs to the cache kmalloc-16384 of size 16384 The buggy address is located 6352 bytes inside of 16384-byte region [ffff8880569693c0, ffff88805696d3c0) The buggy address belongs to the page: page:ffffea00015a5a00 count:1 mapcount:0 mapping:ffff8880569693c0 index:0x0 compound_mapcount: 0 flags: 0x1fffc0000008100(slab|head) raw: 01fffc0000008100 ffff8880569693c0 0000000000000000 0000000100000001 raw: ffffea00018cc020 ffffea00016bce20 ffff8880aa802200 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88805696ab80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88805696ac00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88805696ac80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88805696ad00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88805696ad80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ptrace attach of "/root/syz-executor.3"[12484] was attempted by "/root/syz-executor.3"[12485]