RDX: 0000000000000001 RSI: 0000000000005502 RDI: 0000000000000004 RBP: 00000000006cf018 R08: 0000000000000001 R09: 0000000000000038 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000006 R13: ffffffffffffffff R14: 0000000000000000 R15: 0000000000000000 ================================================================== BUG: KASAN: use-after-free in string+0x2c6/0x2d0 lib/vsprintf.c:604 Read of size 1 at addr ffff8801d79c5080 by task syz-executor215/4685 CPU: 1 PID: 4685 Comm: syz-executor215 Not tainted 4.19.0-rc1+ #215 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+0x1c9/0x2b4 lib/dump_stack.c:113 print_address_description+0x6c/0x20b mm/kasan/report.c:256 kasan_report_error mm/kasan/report.c:354 [inline] kasan_report.cold.7+0x242/0x30d mm/kasan/report.c:412 __asan_report_load1_noabort+0x14/0x20 mm/kasan/report.c:430 string+0x2c6/0x2d0 lib/vsprintf.c:604 vsnprintf+0x48f/0x1b60 lib/vsprintf.c:2293 add_uevent_var+0x140/0x2f0 lib/kobject_uevent.c:659 input_dev_uevent+0x15d/0x860 drivers/input/input.c:1594 dev_uevent+0x340/0x7e0 drivers/base/core.c:1008 kobject_uevent_env+0x45b/0x1110 lib/kobject_uevent.c:547 kobject_uevent+0x1f/0x30 lib/kobject_uevent.c:636 kobject_cleanup lib/kobject.c:649 [inline] kobject_release lib/kobject.c:691 [inline] kref_put include/linux/kref.h:70 [inline] kobject_put+0x1fb/0x280 lib/kobject.c:708 put_device+0x20/0x30 drivers/base/core.c:2024 input_put_device include/linux/input.h:349 [inline] evdev_free+0x4f/0x70 drivers/input/evdev.c:369 device_release+0x7e/0x210 drivers/base/core.c:891 kobject_cleanup lib/kobject.c:662 [inline] kobject_release lib/kobject.c:691 [inline] kref_put include/linux/kref.h:70 [inline] kobject_put+0x194/0x280 lib/kobject.c:708 cdev_default_release+0x3e/0x50 fs/char_dev.c:607 kobject_cleanup lib/kobject.c:662 [inline] kobject_release lib/kobject.c:691 [inline] kref_put include/linux/kref.h:70 [inline] kobject_put+0x194/0x280 lib/kobject.c:708 cdev_put.part.0+0x36/0x50 fs/char_dev.c:368 cdev_put+0x1f/0x30 fs/char_dev.c:366 __fput+0x8ae/0xa40 fs/file_table.c:281 ____fput+0x15/0x20 fs/file_table.c:309 task_work_run+0x1e8/0x2a0 kernel/task_work.c:113 exit_task_work include/linux/task_work.h:22 [inline] do_exit+0x1ae4/0x26e0 kernel/exit.c:867 do_group_exit+0x177/0x440 kernel/exit.c:970 __do_sys_exit_group kernel/exit.c:981 [inline] __se_sys_exit_group kernel/exit.c:979 [inline] __x64_sys_exit_group+0x3e/0x50 kernel/exit.c:979 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x443a68 Code: Bad RIP value. RSP: 002b:00007fff70261298 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000443a68 RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000 RBP: 00000000004c39c8 R08: 00000000000000e7 R09: ffffffffffffffd0 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 00000000006d5180 R14: 0000000000000000 R15: 0000000000000000 Allocated by task 4685: save_stack+0x43/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] kasan_kmalloc+0xc4/0xe0 mm/kasan/kasan.c:553 __do_kmalloc mm/slab.c:3718 [inline] __kmalloc_track_caller+0x14a/0x720 mm/slab.c:3733 kstrndup+0x5f/0xe0 mm/util.c:98 uinput_setup_device_legacy drivers/input/misc/uinput.c:549 [inline] uinput_write+0x2fb/0x1120 drivers/input/misc/uinput.c:621 __vfs_write+0x117/0x9d0 fs/read_write.c:485 vfs_write+0x1fc/0x560 fs/read_write.c:549 ksys_write+0x101/0x260 fs/read_write.c:598 __do_sys_write fs/read_write.c:610 [inline] __se_sys_write fs/read_write.c:607 [inline] __x64_sys_write+0x73/0xb0 fs/read_write.c:607 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 4685: save_stack+0x43/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] __kasan_slab_free+0x11a/0x170 mm/kasan/kasan.c:521 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528 __cache_free mm/slab.c:3498 [inline] kfree+0xd9/0x210 mm/slab.c:3813 uinput_destroy_device+0xf8/0x250 drivers/input/misc/uinput.c:310 uinput_ioctl_handler.isra.10+0x1439/0x2540 drivers/input/misc/uinput.c:880 uinput_ioctl+0x4c/0x60 drivers/input/misc/uinput.c:1047 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:501 [inline] do_vfs_ioctl+0x1de/0x1720 fs/ioctl.c:685 ksys_ioctl+0xa9/0xd0 fs/ioctl.c:702 __do_sys_ioctl fs/ioctl.c:709 [inline] __se_sys_ioctl fs/ioctl.c:707 [inline] __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:707 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 ffff8801d79c5080 which belongs to the cache kmalloc-32 of size 32 The buggy address is located 0 bytes inside of 32-byte region [ffff8801d79c5080, ffff8801d79c50a0) The buggy address belongs to the page: page:ffffea00075e7140 count:1 mapcount:0 mapping:ffff8801dac001c0 index:0xffff8801d79c5fc1 flags: 0x2fffc0000000100(slab) raw: 02fffc0000000100 ffffea00075e0908 ffffea00075e7408 ffff8801dac001c0 raw: ffff8801d79c5fc1 ffff8801d79c5000 000000010000003f 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8801d79c4f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8801d79c5000: 00 00 fc fc fc fc fc fc 00 00 00 fc fc fc fc fc >ffff8801d79c5080: fb fb fb fb fc fc fc fc 07 fc fc fc fc fc fc fc ^ ffff8801d79c5100: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc ffff8801d79c5180: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc ==================================================================