==================================================================
BUG: KASAN: use-after-free in ext4_data_block_valid+0x2d5/0x330 fs/ext4/block_validity.c:211
Read of size 8 at addr ffff8801c9f6e750 by task udevd/12394
CPU: 1 PID: 12394 Comm: udevd Not tainted 4.19.0-rc6-next-20181005+ #88
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+0x1d3/0x2c4 lib/dump_stack.c:113
print_address_description.cold.8+0x9/0x1ff mm/kasan/report.c:256
kasan_report_error mm/kasan/report.c:354 [inline]
kasan_report.cold.9+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
__check_block_validity.constprop.79+0xc1/0x210 fs/ext4/inode.c:402
ext4_map_blocks+0x1029/0x1b60 fs/ext4/inode.c:592
ext4_getblk+0x4f2/0x630 fs/ext4/inode.c:966
ext4_bread_batch+0x7f/0x440 fs/ext4/inode.c:1036
ext4_find_entry+0xd49/0x1b70 fs/ext4/namei.c:1425
ext4_lookup+0x15b/0x700 fs/ext4/namei.c:1557
__lookup_slow+0x2b5/0x540 fs/namei.c:1671
lookup_slow+0x57/0x80 fs/namei.c:1688
walk_component+0x92b/0x25b0 fs/namei.c:1810
link_path_walk.part.40+0xa61/0x1530 fs/namei.c:2141
link_path_walk fs/namei.c:2072 [inline]
path_openat+0x270/0x5160 fs/namei.c:3533
do_filp_open+0x255/0x380 fs/namei.c:3564
do_open_execat+0x221/0x8e0 fs/exec.c:853
open_exec+0x53/0x70 fs/exec.c:885
load_elf_binary+0x96e/0x5620 fs/binfmt_elf.c:780
search_binary_handler+0x17d/0x570 fs/exec.c:1653
exec_binprm fs/exec.c:1695 [inline]
__do_execve_file.isra.33+0x1661/0x25d0 fs/exec.c:1819
do_execveat_common fs/exec.c:1866 [inline]
do_execve fs/exec.c:1883 [inline]
__do_sys_execve fs/exec.c:1964 [inline]
__se_sys_execve fs/exec.c:1959 [inline]
__x64_sys_execve+0x8f/0xc0 fs/exec.c:1959
do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7f3ae8599207
Code: 77 19 f4 48 89 d7 44 89 c0 0f 05 48 3d 00 f0 ff ff 76 e0 f7 d8 64 41 89 01 eb d8 f7 d8 64 41 89 01 eb df b8 3b 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 02 f3 c3 48 8b 15 00 8c 2d 00 f7 d8 64 89 02
RSP: 002b:00007ffe1ba5e7a8 EFLAGS: 00000202 ORIG_RAX: 000000000000003b
RAX: ffffffffffffffda RBX: 00000000ffffffff RCX: 00007f3ae8599207
RDX: 0000000002291430 RSI: 00007ffe1ba5e8a0 RDI: 00007ffe1ba5f8b0
RBP: 0000000000625500 R08: 000000000000179f R09: 000000000000179f
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000002291430
R13: 0000000000000007 R14: 0000000002290250 R15: 0000000000000005
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+0x8181/0xdab0 fs/ext4/super.c:4368
mount_bdev+0x314/0x3e0 fs/super.c:1356
ext4_mount+0x3c/0x50 fs/ext4/super.c:5872
legacy_get_tree+0x131/0x460 fs/fs_context.c:718
vfs_get_tree+0x1cb/0x5c0 fs/super.c:1795
do_new_mount fs/namespace.c:2648 [inline]
do_mount+0x70c/0x1d90 fs/namespace.c:2974
ksys_mount+0x12d/0x140 fs/namespace.c:3190
do_mount_root+0x35/0x1d3 init/do_mounts.c:388
mount_block_root+0x39c/0x6ed init/do_mounts.c:417
mount_root+0x2d3/0x31a init/do_mounts.c:562
prepare_namespace+0x26c/0x2ab init/do_mounts.c:621
kernel_init_freeable+0x590/0x5ae init/main.c:1162
kernel_init+0x11/0x1b2 init/main.c:1063
ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352
Freed by task 12382:
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+0x1451/0x2640 fs/ext4/super.c:5320
legacy_reconfigure+0x14c/0x1c0 fs/fs_context.c:754
reconfigure_super+0x4c0/0xbb0 fs/super.c:982
do_remount fs/namespace.c:2419 [inline]
do_mount+0x18b9/0x1d90 fs/namespace.c:2965
ksys_mount+0x12d/0x140 fs/namespace.c:3190
__do_sys_mount fs/namespace.c:3204 [inline]
__se_sys_mount fs/namespace.c:3201 [inline]
__x64_sys_mount+0xbe/0x150 fs/namespace.c:3201
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 ffff8801c9f6e738
which belongs to the cache ext4_system_zone of size 40
The buggy address is located 24 bytes inside of
40-byte region [ffff8801c9f6e738, ffff8801c9f6e760)
The buggy address belongs to the page:
page:ffffea000727db80 count:1 mapcount:0 mapping:ffff8801d4bcc0c0 index:0xffff8801c9f6efb9
flags: 0x2fffc0000000200(slab)
raw: 02fffc0000000200 ffff8801d4bd0b38 ffff8801d4bd0b38 ffff8801d4bcc0c0
raw: ffff8801c9f6efb9 ffff8801c9f6e000 0000000100000006 0000000000000000
page dumped because: kasan: bad access detected
Memory state around the buggy address:
ffff8801c9f6e600: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff8801c9f6e680: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff8801c9f6e700: fc fc fc fc fc fc fc fb fb fb fb fb fc fc fb fb
^
ffff8801c9f6e780: fb fb fb fc fc fb fb fb fb fb fc fc fb fb fb fb
ffff8801c9f6e800: fb fc fc fb fb fb fb fb fc fc fb fb fb fb fb fc
==================================================================
EXT4-fs (sda1): re-mounted. Opts: noblock_validity,grpid,usrquota,errors=continue,dioread_nolock,sb=0x0000000000000006,,errors=continue
netlink: 40 bytes leftover after parsing attributes in process `syz-executor2'.
netlink: 'syz-executor0': attribute type 1 has an invalid length.
netlink: 4 bytes leftover after parsing attributes in process `syz-executor0'.
netlink: 'syz-executor0': attribute type 1 has an invalid length.
netlink: 4 bytes leftover after parsing attributes in process `syz-executor0'.