================================================================== BUG: KASAN: use-after-free in kobject_put+0x1c1/0x210 lib/kobject.c:735 Read of size 1 at addr ffff88809e5a8cbc by task syz-executor.2/9154 CPU: 1 PID: 9154 Comm: syz-executor.2 Not tainted 5.7.0-rc2-syzkaller #0 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+0x128/0x182 lib/dump_stack.c:118 print_address_description.constprop.8.cold.10+0x9/0x317 mm/kasan/report.c:382 __kasan_report.cold.11+0x35/0x4d mm/kasan/report.c:511 kasan_report+0x32/0x50 mm/kasan/common.c:625 kobject_put+0x1c1/0x210 lib/kobject.c:735 delete_partition+0xe7/0x180 block/partitions/core.c:306 bdev_del_partition+0x156/0x1a0 block/partitions/core.c:530 blkpg_do_ioctl+0x1fa/0x2a0 block/ioctl.c:33 blkpg_ioctl block/ioctl.c:69 [inline] blkdev_ioctl+0x35e/0x580 block/ioctl.c:589 block_ioctl+0xd8/0x130 fs/block_dev.c:1996 vfs_ioctl fs/ioctl.c:47 [inline] ksys_ioctl+0xb8/0x110 fs/ioctl.c:763 __do_sys_ioctl fs/ioctl.c:772 [inline] __se_sys_ioctl fs/ioctl.c:770 [inline] __x64_sys_ioctl+0x6a/0xb0 fs/ioctl.c:770 do_syscall_64+0xc6/0x620 arch/x86/entry/common.c:295 entry_SYSCALL_64_after_hwframe+0x49/0xb3 RIP: 0033:0x45d5b9 Code: 5d b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 2b b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f7cf64abc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000008c40 RCX: 000000000045d5b9 RDX: 0000000020000000 RSI: 0000000000001269 RDI: 0000000000000003 RBP: 000000000118cf80 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118cf4c R13: 00007ffe8469976f R14: 00007f7cf64ac9c0 R15: 000000000118cf4c Allocated by task 9154: save_stack+0x19/0x40 mm/kasan/common.c:49 set_track mm/kasan/common.c:57 [inline] __kasan_kmalloc.constprop.17+0xc1/0xd0 mm/kasan/common.c:495 kmem_cache_alloc_trace+0x156/0x780 mm/slab.c:3551 kmalloc include/linux/slab.h:555 [inline] kzalloc include/linux/slab.h:669 [inline] kobject_create+0x35/0x60 lib/kobject.c:770 kobject_create_and_add+0xf/0x40 lib/kobject.c:796 add_partition+0xa37/0xfc0 block/partitions/core.c:424 bdev_add_partition+0x93/0xe0 block/partitions/core.c:499 blkpg_do_ioctl+0x1ed/0x2a0 block/ioctl.c:52 blkpg_ioctl block/ioctl.c:69 [inline] blkdev_ioctl+0x35e/0x580 block/ioctl.c:589 block_ioctl+0xd8/0x130 fs/block_dev.c:1996 vfs_ioctl fs/ioctl.c:47 [inline] ksys_ioctl+0xb8/0x110 fs/ioctl.c:763 __do_sys_ioctl fs/ioctl.c:772 [inline] __se_sys_ioctl fs/ioctl.c:770 [inline] __x64_sys_ioctl+0x6a/0xb0 fs/ioctl.c:770 do_syscall_64+0xc6/0x620 arch/x86/entry/common.c:295 entry_SYSCALL_64_after_hwframe+0x49/0xb3 Freed by task 9156: save_stack+0x19/0x40 mm/kasan/common.c:49 set_track mm/kasan/common.c:57 [inline] kasan_set_free_info mm/kasan/common.c:317 [inline] __kasan_slab_free+0xf7/0x140 mm/kasan/common.c:456 __cache_free mm/slab.c:3426 [inline] kfree+0x107/0x2b0 mm/slab.c:3757 kobject_cleanup lib/kobject.c:693 [inline] kobject_release lib/kobject.c:722 [inline] kref_put include/linux/kref.h:65 [inline] kobject_put+0x14b/0x210 lib/kobject.c:739 delete_partition+0xe7/0x180 block/partitions/core.c:306 bdev_del_partition+0x156/0x1a0 block/partitions/core.c:530 blkpg_do_ioctl+0x1fa/0x2a0 block/ioctl.c:33 blkpg_ioctl block/ioctl.c:69 [inline] blkdev_ioctl+0x35e/0x580 block/ioctl.c:589 block_ioctl+0xd8/0x130 fs/block_dev.c:1996 vfs_ioctl fs/ioctl.c:47 [inline] ksys_ioctl+0xb8/0x110 fs/ioctl.c:763 __do_sys_ioctl fs/ioctl.c:772 [inline] __se_sys_ioctl fs/ioctl.c:770 [inline] __x64_sys_ioctl+0x6a/0xb0 fs/ioctl.c:770 do_syscall_64+0xc6/0x620 arch/x86/entry/common.c:295 entry_SYSCALL_64_after_hwframe+0x49/0xb3 The buggy address belongs to the object at ffff88809e5a8c80 which belongs to the cache kmalloc-64 of size 64 The buggy address is located 60 bytes inside of 64-byte region [ffff88809e5a8c80, ffff88809e5a8cc0) The buggy address belongs to the page: page:ffffea0002796a00 refcount:1 mapcount:0 mapping:00000000dc90f7be index:0x0 flags: 0xfffe0000000200(slab) raw: 00fffe0000000200 ffffea000225a648 ffffea0002541908 ffff8880aa400380 raw: 0000000000000000 ffff88809e5a8000 0000000100000020 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88809e5a8b80: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc ffff88809e5a8c00: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc >ffff88809e5a8c80: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ^ ffff88809e5a8d00: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff88809e5a8d80: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ==================================================================