================================================================== BUG: KASAN: slab-out-of-bounds in memcpy include/linux/string.h:406 [inline] BUG: KASAN: slab-out-of-bounds in soft_cursor+0x44b/0xa30 drivers/video/fbdev/core/softcursor.c:70 Read of size 16 at addr ffff88809e5b6e10 by task kworker/1:29/22798 CPU: 1 PID: 22798 Comm: kworker/1:29 Not tainted 5.9.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: events_power_efficient fb_flashcursor Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x198/0x1fd lib/dump_stack.c:118 print_address_description.constprop.0.cold+0xae/0x497 mm/kasan/report.c:383 __kasan_report mm/kasan/report.c:513 [inline] kasan_report.cold+0x1f/0x37 mm/kasan/report.c:530 check_memory_region_inline mm/kasan/generic.c:186 [inline] check_memory_region+0x13d/0x180 mm/kasan/generic.c:192 memcpy+0x20/0x60 mm/kasan/common.c:105 memcpy include/linux/string.h:406 [inline] soft_cursor+0x44b/0xa30 drivers/video/fbdev/core/softcursor.c:70 bit_cursor+0xcfe/0x1720 drivers/video/fbdev/core/bitblit.c:377 fb_flashcursor+0x38b/0x430 drivers/video/fbdev/core/fbcon.c:397 process_one_work+0x94c/0x1670 kernel/workqueue.c:2269 worker_thread+0x64c/0x1120 kernel/workqueue.c:2415 kthread+0x3b5/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 Allocated by task 16792: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:48 kasan_set_track mm/kasan/common.c:56 [inline] __kasan_kmalloc.constprop.0+0xbf/0xd0 mm/kasan/common.c:461 __do_kmalloc mm/slab.c:3655 [inline] __kmalloc+0x1b0/0x360 mm/slab.c:3664 kmalloc include/linux/slab.h:559 [inline] fbcon_set_font+0x363/0x9b0 drivers/video/fbdev/core/fbcon.c:2496 con_font_set drivers/tty/vt/vt.c:4663 [inline] con_font_op+0xd26/0x1140 drivers/tty/vt/vt.c:4728 vt_io_ioctl drivers/tty/vt/vt_ioctl.c:595 [inline] vt_ioctl+0x1ce7/0x2e90 drivers/tty/vt/vt_ioctl.c:856 tty_ioctl+0x1019/0x15f0 drivers/tty/tty_io.c:2656 vfs_ioctl fs/ioctl.c:48 [inline] __do_sys_ioctl fs/ioctl.c:753 [inline] __se_sys_ioctl fs/ioctl.c:739 [inline] __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:739 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Last call_rcu(): kasan_save_stack+0x1b/0x40 mm/kasan/common.c:48 kasan_record_aux_stack+0x82/0xb0 mm/kasan/generic.c:346 __call_rcu kernel/rcu/tree.c:2894 [inline] call_rcu+0x15e/0x7c0 kernel/rcu/tree.c:2968 percpu_ref_put_many include/linux/percpu-refcount.h:309 [inline] percpu_ref_put include/linux/percpu-refcount.h:325 [inline] percpu_ref_call_confirm_rcu lib/percpu-refcount.c:131 [inline] percpu_ref_switch_to_atomic_rcu+0x536/0x620 lib/percpu-refcount.c:166 rcu_do_batch kernel/rcu/tree.c:2428 [inline] rcu_core+0x5ca/0x1130 kernel/rcu/tree.c:2656 __do_softirq+0x1f8/0xb23 kernel/softirq.c:298 Second to last call_rcu(): kasan_save_stack+0x1b/0x40 mm/kasan/common.c:48 kasan_record_aux_stack+0x82/0xb0 mm/kasan/generic.c:346 __call_rcu kernel/rcu/tree.c:2894 [inline] call_rcu+0x15e/0x7c0 kernel/rcu/tree.c:2968 __percpu_ref_switch_to_atomic lib/percpu-refcount.c:192 [inline] __percpu_ref_switch_mode+0x365/0x720 lib/percpu-refcount.c:237 percpu_ref_kill_and_confirm+0x94/0x350 lib/percpu-refcount.c:350 blkg_destroy_all+0xc0/0x170 block/blk-cgroup.c:423 blkcg_exit_queue+0x11/0x20 block/blk-cgroup.c:1185 blk_exit_queue block/blk-sysfs.c:894 [inline] blk_release_queue+0x1aa/0x3d0 block/blk-sysfs.c:940 kobject_cleanup lib/kobject.c:705 [inline] kobject_release lib/kobject.c:736 [inline] kref_put include/linux/kref.h:65 [inline] kobject_put+0x171/0x270 lib/kobject.c:753 scsi_device_dev_release_usercontext+0x5d6/0xcb0 drivers/scsi/scsi_sysfs.c:465 execute_in_process_context+0x37/0x150 kernel/workqueue.c:3321 device_release+0x71/0x200 drivers/base/core.c:1796 kobject_cleanup lib/kobject.c:705 [inline] kobject_release lib/kobject.c:736 [inline] kref_put include/linux/kref.h:65 [inline] kobject_put+0x171/0x270 lib/kobject.c:753 put_device+0x1b/0x30 drivers/base/core.c:3025 __scsi_remove_device+0x1dd/0x3d0 drivers/scsi/scsi_sysfs.c:1455 scsi_probe_and_add_lun+0x1f7f/0x3530 drivers/scsi/scsi_scan.c:1177 __scsi_scan_target+0x225/0xe40 drivers/scsi/scsi_scan.c:1561 scsi_scan_channel drivers/scsi/scsi_scan.c:1649 [inline] scsi_scan_channel+0x14b/0x1f0 drivers/scsi/scsi_scan.c:1625 scsi_scan_host_selected+0x2e7/0x3c0 drivers/scsi/scsi_scan.c:1678 do_scsi_scan_host+0x1e8/0x260 drivers/scsi/scsi_scan.c:1816 do_scan_async+0x3e/0x510 drivers/scsi/scsi_scan.c:1826 async_run_entry_fn+0x121/0x530 kernel/async.c:123 process_one_work+0x94c/0x1670 kernel/workqueue.c:2269 worker_thread+0x64c/0x1120 kernel/workqueue.c:2415 kthread+0x3b5/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 The buggy address belongs to the object at ffff88809e5b6c00 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 16 bytes to the right of 512-byte region [ffff88809e5b6c00, ffff88809e5b6e00) The buggy address belongs to the page: page:0000000089829f88 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x9e5b6 flags: 0xfffe0000000200(slab) raw: 00fffe0000000200 ffffea0002441648 ffffea000287ec48 ffff8880aa040600 raw: 0000000000000000 ffff88809e5b6000 0000000100000004 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88809e5b6d00: 00 00 fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88809e5b6d80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88809e5b6e00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff88809e5b6e80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88809e5b6f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================