================================================================== EXT4-fs (sda1): re-mounted. Opts: noblock_validity,,errors=continue BUG: KASAN: use-after-free in ext4_data_block_valid+0x2d5/0x330 fs/ext4/block_validity.c:211 Read of size 8 at addr ffff8801d1849750 by task syz-executor2/10120 CPU: 1 PID: 10120 Comm: syz-executor2 Not tainted 4.20.0-rc1+ #101 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+0x244/0x39d lib/dump_stack.c:113 print_address_description.cold.7+0x9/0x1ff mm/kasan/report.c:256 kasan_report_error mm/kasan/report.c:354 [inline] kasan_report.cold.8+0x242/0x309 mm/kasan/report.c:412 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:433 ext4_data_block_valid+0x2d5/0x330 fs/ext4/block_validity.c:211 ext4_mb_mark_diskspace_used+0x533/0x10d0 fs/ext4/mballoc.c:2966 ext4_mb_new_blocks+0xea5/0x4840 fs/ext4/mballoc.c:4555 ext4_ext_map_blocks+0x2724/0x48f0 fs/ext4/extents.c:4404 ext4_map_blocks+0x8f7/0x1b50 fs/ext4/inode.c:636 ext4_getblk+0x10e/0x630 fs/ext4/inode.c:966 ext4_bread+0x95/0x2b0 fs/ext4/inode.c:1016 ext4_append+0x14e/0x370 fs/ext4/namei.c:66 ext4_init_new_dir fs/ext4/namei.c:2588 [inline] ext4_mkdir+0x532/0xe60 fs/ext4/namei.c:2635 vfs_mkdir+0x42e/0x6b0 fs/namei.c:3817 do_mkdirat+0x27a/0x310 fs/namei.c:3840 __do_sys_mkdir fs/namei.c:3856 [inline] __se_sys_mkdir fs/namei.c:3854 [inline] __x64_sys_mkdir+0x5c/0x80 fs/namei.c:3854 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x456987 Code: 1f 40 00 b8 5a 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 cd bf fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 b8 53 00 00 00 0f 05 <48> 3d 01 f0 ff ff 0f 83 ad bf fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007ffe014cfed8 EFLAGS: 00000206 ORIG_RAX: 0000000000000053 RAX: ffffffffffffffda RBX: 000000000005a059 RCX: 0000000000456987 RDX: 00007ffe014cff25 RSI: 00000000000001ff RDI: 00007ffe014cff20 RBP: 000000000000036b R08: 0000000000000000 R09: 0000000000000005 R10: 0000000000000064 R11: 0000000000000206 R12: 0000000000000006 R13: 000000000005a020 R14: 00000000000000e6 R15: 0000000000000002 Allocated by task 1: save_stack+0x43/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] kasan_kmalloc+0xc7/0xe0 mm/kasan/kasan.c:553 kasan_slab_alloc+0x12/0x20 mm/kasan/kasan.c:490 kmem_cache_alloc+0x12e/0x730 mm/slab.c:3554 add_system_zone+0x2e5/0x5f0 fs/ext4/block_validity.c:85 ext4_setup_system_zone+0x208/0x520 fs/ext4/block_validity.c:169 ext4_fill_super+0x8183/0xdbc0 fs/ext4/super.c:4384 mount_bdev+0x30c/0x3e0 fs/super.c:1158 ext4_mount+0x34/0x40 fs/ext4/super.c:5892 mount_fs+0xae/0x31d fs/super.c:1261 vfs_kern_mount.part.35+0xdc/0x4f0 fs/namespace.c:961 vfs_kern_mount fs/namespace.c:951 [inline] do_new_mount fs/namespace.c:2457 [inline] do_mount+0x581/0x31f0 fs/namespace.c:2789 ksys_mount+0x12d/0x140 fs/namespace.c:3005 do_mount_root+0x35/0x1d3 init/do_mounts.c:387 mount_block_root+0x39c/0x6ed init/do_mounts.c:416 mount_root+0x358/0x39f init/do_mounts.c:561 prepare_namespace+0x26c/0x2ab init/do_mounts.c:620 kernel_init_freeable+0x69b/0x6b9 init/main.c:1170 kernel_init+0x11/0x1ae init/main.c:1071 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352 Freed by task 16345: save_stack+0x43/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/kasan.c:521 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528 __cache_free mm/slab.c:3498 [inline] kmem_cache_free+0x83/0x290 mm/slab.c:3760 ext4_release_system_zone+0x7c/0x110 fs/ext4/block_validity.c:187 ext4_setup_system_zone+0x3ef/0x520 fs/ext4/block_validity.c:151 ext4_remount+0x16fc/0x2980 fs/ext4/super.c:5337 do_remount_sb+0x350/0x7b0 fs/super.c:888 do_remount fs/namespace.c:2278 [inline] do_mount+0x1513/0x31f0 fs/namespace.c:2780 ksys_mount+0x12d/0x140 fs/namespace.c:3005 __do_sys_mount fs/namespace.c:3019 [inline] __se_sys_mount fs/namespace.c:3016 [inline] __x64_sys_mount+0xbe/0x150 fs/namespace.c:3016 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff8801d1849738 which belongs to the cache ext4_system_zone of size 40 The buggy address is located 24 bytes inside of 40-byte region [ffff8801d1849738, ffff8801d1849760) The buggy address belongs to the page: page:ffffea0007461240 count:1 mapcount:0 mapping:ffff8801d474fc40 index:0xffff8801d1849fb9 flags: 0x2fffc0000000200(slab) raw: 02fffc0000000200 ffff8801d4749338 ffff8801d4749338 ffff8801d474fc40 raw: ffff8801d1849fb9 ffff8801d1849000 0000000100000006 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8801d1849600: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8801d1849680: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff8801d1849700: fc fc fc fc fc fc fc fb fb fb fb fb fc fc fb fb ^ ffff8801d1849780: fb fb fb fc fc fb fb fb fb fb fc fc fb fb fb fb ffff8801d1849800: fb fc fc fb fb fb fb fb fc fc fb fb fb fb fb fc ==================================================================