device-mapper: table: 248:0: zero-length target
device-mapper: ioctl: error adding target to table
==================================================================
BUG: KASAN: slab-use-after-free in snapshot_ctr+0x5cb/0x1340 drivers/md/dm-snap.c:1284
Read of size 8 at addr ffff88803b6b1198 by task syz.0.0/5340

CPU: 0 UID: 0 PID: 5340 Comm: syz.0.0 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
 print_address_description+0x55/0x1e0 mm/kasan/report.c:378
 print_report+0x58/0x70 mm/kasan/report.c:482
 kasan_report+0x117/0x150 mm/kasan/report.c:595
 snapshot_ctr+0x5cb/0x1340 drivers/md/dm-snap.c:1284
 dm_table_add_target+0x58d/0xc70 drivers/md/dm-table.c:749
 populate_table drivers/md/dm-ioctl.c:1602 [inline]
 table_load+0x325/0x8a0 drivers/md/dm-ioctl.c:1645
 ctl_ioctl drivers/md/dm-ioctl.c:2221 [inline]
 dm_ctl_ioctl+0x9ec/0xe10 drivers/md/dm-ioctl.c:2243
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:597 [inline]
 __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f60e819f559
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f60e8f7ffe8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f60e8425fa0 RCX: 00007f60e819f559
RDX: 0000200000000340 RSI: 00000000c138fd09 RDI: 0000000000000003
RBP: 00007f60e8236b20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f60e8426038 R14: 00007f60e8425fa0 R15: 00007fff373483f8
 </TASK>

Allocated by task 5340:
 kasan_save_stack mm/kasan/common.c:57 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
 poison_kmalloc_redzone mm/kasan/common.c:409 [inline]
 __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:426
 kasan_kmalloc include/linux/kasan.h:263 [inline]
 __kmalloc_cache_node_noprof+0x3cc/0x620 mm/slub.c:5699
 _kmalloc_node_noprof include/linux/slab.h:1196 [inline]
 open_table_device drivers/md/dm.c:733 [inline]
 dm_get_table_device+0x23e/0x730 drivers/md/dm.c:821
 dm_get_device+0x327/0x760 drivers/md/dm-table.c:388
 snapshot_ctr+0x2b2/0x1340 drivers/md/dm-snap.c:1269
 dm_table_add_target+0x58d/0xc70 drivers/md/dm-table.c:749
 populate_table drivers/md/dm-ioctl.c:1602 [inline]
 table_load+0x325/0x8a0 drivers/md/dm-ioctl.c:1645
 ctl_ioctl drivers/md/dm-ioctl.c:2221 [inline]
 dm_ctl_ioctl+0x9ec/0xe10 drivers/md/dm-ioctl.c:2243
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:597 [inline]
 __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 5340:
 kasan_save_stack mm/kasan/common.c:57 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:584
 poison_slab_object mm/kasan/common.c:264 [inline]
 __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:296
 kasan_slab_free include/linux/kasan.h:235 [inline]
 slab_free_hook mm/slub.c:2780 [inline]
 slab_free mm/slub.c:6630 [inline]
 kfree+0x1c5/0x650 mm/slub.c:6923
 close_table_device drivers/md/dm.c:798 [inline]
 dm_put_table_device+0x255/0x2a0 drivers/md/dm.c:841
 upgrade_mode drivers/md/dm-table.c:326 [inline]
 dm_get_device+0x56f/0x760 drivers/md/dm-table.c:399
 snapshot_ctr+0x471/0x1340 drivers/md/dm-snap.c:1279
 dm_table_add_target+0x58d/0xc70 drivers/md/dm-table.c:749
 populate_table drivers/md/dm-ioctl.c:1602 [inline]
 table_load+0x325/0x8a0 drivers/md/dm-ioctl.c:1645
 ctl_ioctl drivers/md/dm-ioctl.c:2221 [inline]
 dm_ctl_ioctl+0x9ec/0xe10 drivers/md/dm-ioctl.c:2243
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:597 [inline]
 __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff88803b6b1180
 which belongs to the cache kmalloc-96 of size 96
The buggy address is located 24 bytes inside of
 freed 96-byte region [ffff88803b6b1180, ffff88803b6b11e0)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x3b6b1
flags: 0x4fff00000000000(node=1|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 04fff00000000000 ffff88801c841280 dead000000000100 dead000000000122
raw: 0000000000000000 0000000000200020 00000000f5000000 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Unmovable, gfp_mask 0xd2cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 1, tgid 1 (swapper/0), ts 23291992585
 set_page_owner include/linux/page_owner.h:33 [inline]
 post_alloc_hook+0x1f9/0x250 mm/page_alloc.c:1856
 prep_new_page mm/page_alloc.c:1864 [inline]
 get_page_from_freelist+0x220f/0x2280 mm/page_alloc.c:3935
 __alloc_frozen_pages_noprof+0x1fe/0x410 mm/page_alloc.c:5444
 alloc_slab_page mm/slub.c:3384 [inline]
 allocate_slab+0x7d/0x5e0 mm/slub.c:3499
 new_slab mm/slub.c:3550 [inline]
 refill_objects+0x2d5/0x350 mm/slub.c:7539
 refill_sheaf mm/slub.c:2917 [inline]
 __pcs_replace_empty_main+0x2c8/0x6c0 mm/slub.c:4811
 alloc_from_pcs mm/slub.c:4887 [inline]
 slab_alloc_node mm/slub.c:5021 [inline]
 __kmalloc_cache_node_noprof+0x446/0x620 mm/slub.c:5695
 _kmalloc_node_noprof include/linux/slab.h:1196 [inline]
 __get_vm_area_node+0x155/0x2f0 mm/vmalloc.c:3270
 __vmalloc_node_range_noprof+0x36e/0x16f0 mm/vmalloc.c:4112
 __vmalloc_node_noprof mm/vmalloc.c:4213 [inline]
 vzalloc_noprof+0xb2/0xe0 mm/vmalloc.c:4291
 tpg_alloc+0xdc/0x860 drivers/media/common/v4l2-tpg/v4l2-tpg-core.c:132
 vivid_create_instance drivers/media/test-drivers/vivid/vivid-core.c:1858 [inline]
 vivid_probe+0x1b55/0x70c0 drivers/media/test-drivers/vivid/vivid-core.c:2096
 platform_probe+0xf9/0x190 drivers/base/platform.c:1508
 call_driver_probe drivers/base/dd.c:-1 [inline]
 really_probe+0x254/0xae0 drivers/base/dd.c:707
 __driver_probe_device+0x1e8/0x360 drivers/base/dd.c:869
 driver_probe_device+0x4f/0x240 drivers/base/dd.c:899
page last free pid 1 tgid 1 ts 23291924360 stack trace:
 reset_page_owner include/linux/page_owner.h:26 [inline]
 __free_pages_prepare mm/page_alloc.c:1403 [inline]
 __free_frozen_pages+0xc97/0xd90 mm/page_alloc.c:2954
 __kasan_populate_vmalloc_do mm/kasan/shadow.c:393 [inline]
 __kasan_populate_vmalloc+0x1a8/0x1c0 mm/kasan/shadow.c:424
 kasan_populate_vmalloc include/linux/kasan.h:580 [inline]
 alloc_vmap_area+0xd10/0x1410 mm/vmalloc.c:2151
 __get_vm_area_node+0x200/0x2f0 mm/vmalloc.c:3281
 __vmalloc_node_range_noprof+0x36e/0x16f0 mm/vmalloc.c:4112
 __vmalloc_node_noprof mm/vmalloc.c:4213 [inline]
 vzalloc_noprof+0xb2/0xe0 mm/vmalloc.c:4291
 tpg_alloc+0xa2/0x860 drivers/media/common/v4l2-tpg/v4l2-tpg-core.c:124
 vivid_create_instance drivers/media/test-drivers/vivid/vivid-core.c:1858 [inline]
 vivid_probe+0x1b55/0x70c0 drivers/media/test-drivers/vivid/vivid-core.c:2096
 platform_probe+0xf9/0x190 drivers/base/platform.c:1508
 call_driver_probe drivers/base/dd.c:-1 [inline]
 really_probe+0x254/0xae0 drivers/base/dd.c:707
 __driver_probe_device+0x1e8/0x360 drivers/base/dd.c:869
 driver_probe_device+0x4f/0x240 drivers/base/dd.c:899
 __driver_attach+0x34e/0x630 drivers/base/dd.c:1300
 bus_for_each_dev+0x23b/0x2c0 drivers/base/bus.c:386
 bus_add_driver+0x38f/0x6e0 drivers/base/bus.c:785
 driver_register+0x23a/0x320 drivers/base/driver.c:174

Memory state around the buggy address:
 ffff88803b6b1080: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc
 ffff88803b6b1100: 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc
>ffff88803b6b1180: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
                            ^
 ffff88803b6b1200: 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc
 ffff88803b6b1280: 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc
==================================================================