================================================================== BUG: KASAN: use-after-free in ext4_data_block_valid+0x28a/0x2e0 fs/ext4/block_validity.c:210 Read of size 8 at addr ffff8801d52fabb0 by task syz-executor2/20295 CPU: 0 PID: 20295 Comm: syz-executor2 Not tainted 4.9.135+ #65 ffff8801d7ae71d0 ffffffff81b42b89 ffffea000754be80 ffff8801d52fabb0 0000000000000000 ffff8801d52fabb0 00000000000025f5 ffff8801d7ae7208 ffffffff815009ad ffff8801d52fabb0 0000000000000008 0000000000000000 Call Trace: [] __dump_stack lib/dump_stack.c:15 [inline] [] dump_stack+0xc1/0x128 lib/dump_stack.c:51 [] print_address_description+0x6c/0x234 mm/kasan/report.c:256 [] kasan_report_error mm/kasan/report.c:355 [inline] [] kasan_report.cold.6+0x242/0x2fe mm/kasan/report.c:412 FAT-fs (loop0): Unrecognized mount option "appraise_type=imasig" or missing value [] __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:433 [] ext4_data_block_valid+0x28a/0x2e0 fs/ext4/block_validity.c:210 [] __check_block_validity.constprop.26+0xc1/0x200 fs/ext4/inode.c:378 [] ext4_map_blocks+0xc80/0x16d0 fs/ext4/inode.c:568 [] ext4_getblk+0x2cc/0x450 fs/ext4/inode.c:943 [] ext4_find_entry+0xa94/0x12c0 fs/ext4/namei.c:1419 [] ext4_lookup+0x139/0x5e0 fs/ext4/namei.c:1558 [] lookup_slow+0x24a/0x470 fs/namei.c:1668 [] walk_component+0x822/0xcf0 fs/namei.c:1784 [] link_path_walk+0x8c2/0x1230 fs/namei.c:2120 [] path_mountpoint+0x66/0x6c0 fs/namei.c:2696 [] filename_mountpoint.part.19+0x15b/0x310 fs/namei.c:2717 [] filename_mountpoint fs/namei.c:2714 [inline] [] user_path_mountpoint_at+0x49/0x70 fs/namei.c:2747 [] SYSC_umount fs/namespace.c:1716 [inline] [] SyS_umount+0x13d/0xcb0 fs/namespace.c:1700 [] do_syscall_64+0x19f/0x550 arch/x86/entry/common.c:285 [] entry_SYSCALL_64_after_swapgs+0x5d/0xdb Allocated by task 1: save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:57 save_stack mm/kasan/kasan.c:505 [inline] set_track mm/kasan/kasan.c:517 [inline] kasan_kmalloc.part.1+0x62/0xf0 mm/kasan/kasan.c:609 kasan_kmalloc+0xaf/0xc0 mm/kasan/kasan.c:594 kasan_slab_alloc+0x12/0x20 mm/kasan/kasan.c:547 slab_post_alloc_hook mm/slab.h:417 [inline] slab_alloc_node mm/slub.c:2715 [inline] slab_alloc mm/slub.c:2723 [inline] kmem_cache_alloc+0xd5/0x2b0 mm/slub.c:2728 add_system_zone+0x26f/0x500 fs/ext4/block_validity.c:84 ext4_setup_system_zone+0x30a/0x490 fs/ext4/block_validity.c:168 ext4_fill_super+0x718f/0xb800 fs/ext4/super.c:4180 mount_bdev+0x2be/0x380 fs/super.c:1100 ext4_mount+0x34/0x40 fs/ext4/super.c:5612 mount_fs+0x28c/0x370 fs/super.c:1206 vfs_kern_mount.part.8+0xd1/0x4b0 fs/namespace.c:1000 vfs_kern_mount fs/namespace.c:982 [inline] do_new_mount fs/namespace.c:2537 [inline] do_mount+0x3c9/0x28a0 fs/namespace.c:2859 SYSC_mount fs/namespace.c:3075 [inline] SyS_mount+0xea/0x100 fs/namespace.c:3052 do_mount_root init/do_mounts.c:366 [inline] mount_block_root+0x35d/0x711 init/do_mounts.c:396 mount_root+0x77/0x7a init/do_mounts.c:541 prepare_namespace+0x1d3/0x210 init/do_mounts.c:601 kernel_init_freeable+0x38e/0x3ac init/main.c:1036 kernel_init+0x11/0x15e init/main.c:946 ret_from_fork+0x5c/0x70 arch/x86/entry/entry_64.S:373 Freed by task 621: save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:57 save_stack mm/kasan/kasan.c:505 [inline] set_track mm/kasan/kasan.c:517 [inline] kasan_slab_free+0xac/0x190 mm/kasan/kasan.c:582 slab_free_hook mm/slub.c:1355 [inline] slab_free_freelist_hook mm/slub.c:1377 [inline] slab_free mm/slub.c:2958 [inline] kmem_cache_free+0xbe/0x310 mm/slub.c:2980 ext4_release_system_zone+0x7c/0x110 fs/ext4/block_validity.c:186 ext4_setup_system_zone+0x3cd/0x490 fs/ext4/block_validity.c:150 ext4_remount+0xc57/0x1c50 fs/ext4/super.c:5104 do_remount_sb2+0x351/0x7d0 fs/super.c:825 do_remount fs/namespace.c:2352 [inline] do_mount+0xf91/0x28a0 fs/namespace.c:2850 SYSC_mount fs/namespace.c:3075 [inline] SyS_mount+0xea/0x100 fs/namespace.c:3052 do_syscall_64+0x19f/0x550 arch/x86/entry/common.c:285 entry_SYSCALL_64_after_swapgs+0x5d/0xdb The buggy address belongs to the object at ffff8801d52fab98 which belongs to the cache ext4_system_zone of size 40 The buggy address is located 24 bytes inside of 40-byte region [ffff8801d52fab98, ffff8801d52fabc0) The buggy address belongs to the page: page:ffffea000754be80 count:1 mapcount:0 mapping: (null) index:0x0 flags: 0x4000000000000080(slab) page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8801d52faa80: fb fb fb fb fb fc fc fb fb fb fb fb fc fc fb fb ffff8801d52fab00: fb fb fb fc fc fb fb fb fb fb fc fc fb fb fb fb >ffff8801d52fab80: fb fc fc fb fb fb fb fb fc fc fc fc fc fc fc fc ^ ffff8801d52fac00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8801d52fac80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================