================================================================== BUG: KASAN: use-after-free in free_fs_info fs/btrfs/ctree.h:2931 [inline] BUG: KASAN: use-after-free in btrfs_mount+0x1c3f/0x1fe0 fs/btrfs/super.c:1650 Read of size 8 at addr ffff8880816d4158 by task syz-executor.1/6697 CPU: 1 PID: 6697 Comm: syz-executor.1 Not tainted 4.14.198-syzkaller #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+0x1b2/0x283 lib/dump_stack.c:58 print_address_description.cold+0x54/0x1d3 mm/kasan/report.c:252 kasan_report_error.cold+0x8a/0x194 mm/kasan/report.c:351 kasan_report mm/kasan/report.c:409 [inline] __asan_report_load8_noabort+0x68/0x70 mm/kasan/report.c:430 free_fs_info fs/btrfs/ctree.h:2931 [inline] btrfs_mount+0x1c3f/0x1fe0 fs/btrfs/super.c:1650 hfs: unable to parse mount options mount_fs+0x92/0x2a0 fs/super.c:1237 vfs_kern_mount.part.0+0x5b/0x470 fs/namespace.c:1046 vfs_kern_mount+0x3c/0x60 fs/namespace.c:1036 mount_subvol fs/btrfs/super.c:1398 [inline] btrfs_mount+0x42a/0x1fe0 fs/btrfs/super.c:1569 mount_fs+0x92/0x2a0 fs/super.c:1237 vfs_kern_mount.part.0+0x5b/0x470 fs/namespace.c:1046 vfs_kern_mount fs/namespace.c:1036 [inline] do_new_mount fs/namespace.c:2549 [inline] do_mount+0xe53/0x2a00 fs/namespace.c:2879 FAULT_INJECTION: forcing a failure. name failslab, interval 1, probability 0, space 0, times 0 SYSC_mount fs/namespace.c:3095 [inline] SyS_mount+0xa8/0x120 fs/namespace.c:3072 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x46004a RSP: 002b:00007f3f41188a88 EFLAGS: 00000202 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007f3f41188b20 RCX: 000000000046004a RDX: 0000000020000000 RSI: 0000000020000100 RDI: 00007f3f41188ae0 RBP: 00007f3f41188ae0 R08: 00007f3f41188b20 R09: 0000000020000000 R10: 0000000000000000 R11: 0000000000000202 R12: 0000000020000000 R13: 0000000020000100 R14: 0000000020000200 R15: 0000000020014900 CPU: 0 PID: 6725 Comm: syz-executor.2 Not tainted 4.14.198-syzkaller #0 Allocated by task 6697: Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 save_stack mm/kasan/kasan.c:447 [inline] set_track mm/kasan/kasan.c:459 [inline] kasan_kmalloc+0xeb/0x160 mm/kasan/kasan.c:551 Call Trace: __do_kmalloc_node mm/slab.c:3682 [inline] __kmalloc_node+0x4c/0x70 mm/slab.c:3689 __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x1b2/0x283 lib/dump_stack.c:58 kmalloc_node include/linux/slab.h:530 [inline] kvmalloc_node+0x88/0xd0 mm/util.c:397 fail_dump lib/fault-inject.c:51 [inline] should_fail.cold+0x10a/0x154 lib/fault-inject.c:149 kvmalloc include/linux/mm.h:531 [inline] kvzalloc include/linux/mm.h:539 [inline] btrfs_mount+0x911/0x1fe0 fs/btrfs/super.c:1590 should_failslab+0xd6/0x130 mm/failslab.c:32 mount_fs+0x92/0x2a0 fs/super.c:1237 vfs_kern_mount.part.0+0x5b/0x470 fs/namespace.c:1046 slab_pre_alloc_hook mm/slab.h:421 [inline] slab_alloc mm/slab.c:3376 [inline] __do_kmalloc mm/slab.c:3718 [inline] __kmalloc+0x2c1/0x400 mm/slab.c:3729 vfs_kern_mount+0x3c/0x60 fs/namespace.c:1036 mount_subvol fs/btrfs/super.c:1398 [inline] btrfs_mount+0x42a/0x1fe0 fs/btrfs/super.c:1569 kmalloc include/linux/slab.h:493 [inline] SYSC_memfd_create mm/shmem.c:3738 [inline] SyS_memfd_create+0xbc/0x3c0 mm/shmem.c:3708 mount_fs+0x92/0x2a0 fs/super.c:1237 vfs_kern_mount.part.0+0x5b/0x470 fs/namespace.c:1046 vfs_kern_mount fs/namespace.c:1036 [inline] do_new_mount fs/namespace.c:2549 [inline] do_mount+0xe53/0x2a00 fs/namespace.c:2879 SYSC_mount fs/namespace.c:3095 [inline] SyS_mount+0xa8/0x120 fs/namespace.c:3072 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb entry_SYSCALL_64_after_hwframe+0x46/0xbb Freed by task 6697: RIP: 0033:0x45d5f9 save_stack mm/kasan/kasan.c:447 [inline] set_track mm/kasan/kasan.c:459 [inline] kasan_slab_free+0xc3/0x1a0 mm/kasan/kasan.c:524 RSP: 002b:00007f8f97b36a28 EFLAGS: 00000246 ORIG_RAX: 000000000000013f __cache_free mm/slab.c:3496 [inline] kfree+0xc9/0x250 mm/slab.c:3815 RAX: ffffffffffffffda RBX: 0000000020000680 RCX: 000000000045d5f9 kvfree+0x45/0x50 mm/util.c:416 RDX: 00007f8f97b36ae0 RSI: 0000000000000000 RDI: 00000000004c2083 deactivate_locked_super+0x6c/0xd0 fs/super.c:319 RBP: 0000000000000000 R08: 00007f8f97b36ad8 R09: 0000000000000000 sget_userns+0x9c4/0xc10 fs/super.c:537 R10: 00007f8f97b36adc R11: 0000000000000246 R12: 0000000000000000 sget+0xd1/0x110 fs/super.c:572 R13: 0000000020000140 R14: 0000000020000680 R15: 0000000020000800 btrfs_mount+0xbbe/0x1fe0 fs/btrfs/super.c:1616 mount_fs+0x92/0x2a0 fs/super.c:1237 vfs_kern_mount.part.0+0x5b/0x470 fs/namespace.c:1046 vfs_kern_mount+0x3c/0x60 fs/namespace.c:1036 mount_subvol fs/btrfs/super.c:1398 [inline] btrfs_mount+0x42a/0x1fe0 fs/btrfs/super.c:1569 mount_fs+0x92/0x2a0 fs/super.c:1237 vfs_kern_mount.part.0+0x5b/0x470 fs/namespace.c:1046 vfs_kern_mount fs/namespace.c:1036 [inline] do_new_mount fs/namespace.c:2549 [inline] do_mount+0xe53/0x2a00 fs/namespace.c:2879 SYSC_mount fs/namespace.c:3095 [inline] SyS_mount+0xa8/0x120 fs/namespace.c:3072 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb The buggy address belongs to the object at ffff8880816d28c0 which belongs to the cache kmalloc-16384 of size 16384 The buggy address is located 6296 bytes inside of 16384-byte region [ffff8880816d28c0, ffff8880816d68c0) The buggy address belongs to the page: page:ffffea000205b400 count:1 mapcount:0 mapping:ffff8880816d28c0 index:0x0 compound_mapcount: 0 flags: 0xfffe0000008100(slab|head) raw: 00fffe0000008100 ffff8880816d28c0 0000000000000000 0000000100000001 raw: ffffea000209cc20 ffffea0001a42c20 ffff88812fe48200 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880816d4000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880816d4080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8880816d4100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880816d4180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880816d4200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================