RDX: 0000000000000000 RSI: 00000000080daf20 RDI: 00000000080f0f84 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 ================================================================== BUG: KASAN: use-after-free in string+0x2ea/0x310 lib/vsprintf.c:593 Read of size 1 at addr ffff88011e55df40 by task syz-executor064/13761 CPU: 0 PID: 13761 Comm: syz-executor064 Not tainted 4.13.0-rc3+ #1 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:16 [inline] dump_stack+0x145/0x1e1 lib/dump_stack.c:52 print_address_description.cold.7+0x9/0x1c9 mm/kasan/report.c:252 kasan_report_error mm/kasan/report.c:351 [inline] kasan_report.cold.8+0x121/0x2da mm/kasan/report.c:408 __asan_report_load1_noabort+0x14/0x20 mm/kasan/report.c:426 string+0x2ea/0x310 lib/vsprintf.c:593 vsnprintf+0x392/0x1820 lib/vsprintf.c:2184 add_uevent_var+0x11b/0x280 lib/kobject_uevent.c:538 input_dev_uevent+0x13f/0x6b0 drivers/input/input.c:1592 dev_uevent+0x2a0/0x700 drivers/base/core.c:922 kobject_uevent_env+0x3b1/0x9eb lib/kobject_uevent.c:401 kobject_uevent+0xb/0xd lib/kobject_uevent.c:515 kobject_cleanup lib/kobject.c:635 [inline] kobject_release lib/kobject.c:677 [inline] kref_put include/linux/kref.h:70 [inline] kobject_put.cold.10+0x147/0x2aa lib/kobject.c:694 put_device+0x12/0x20 drivers/base/core.c:1799 input_put_device include/linux/input.h:345 [inline] evdev_free+0x45/0x60 drivers/input/evdev.c:363 device_release+0x71/0x170 drivers/base/core.c:810 kobject_cleanup lib/kobject.c:648 [inline] kobject_release lib/kobject.c:677 [inline] kref_put include/linux/kref.h:70 [inline] kobject_put.cold.10+0x22a/0x2aa lib/kobject.c:694 cdev_default_release+0x39/0x50 fs/char_dev.c:582 kobject_cleanup lib/kobject.c:648 [inline] kobject_release lib/kobject.c:677 [inline] kref_put include/linux/kref.h:70 [inline] kobject_put.cold.10+0x22a/0x2aa lib/kobject.c:694 cdev_put.part.0+0x31/0x50 fs/char_dev.c:343 cdev_put+0xe/0x20 fs/char_dev.c:340 __fput+0x67a/0x900 fs/file_table.c:214 ____fput+0x9/0x10 fs/file_table.c:246 task_work_run+0x14e/0x230 kernel/task_work.c:116 exit_task_work include/linux/task_work.h:21 [inline] do_exit+0xca2/0x17d0 kernel/exit.c:865 do_group_exit+0x135/0x3b0 kernel/exit.c:969 SYSC_exit_group kernel/exit.c:980 [inline] SyS_exit_group+0x18/0x20 kernel/exit.c:978 do_syscall_32_irqs_on arch/x86/entry/common.c:326 [inline] do_fast_syscall_32+0x3cb/0xd95 arch/x86/entry/common.c:388 entry_SYSENTER_compat+0x51/0x60 arch/x86/entry/entry_64_compat.S:124 RIP: 0023:0xf7f29ca9 RSP: 002b:00000000ffa67bbc EFLAGS: 00000296 ORIG_RAX: 00000000000000fc RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00000000080f1298 RDX: 0000000000000000 RSI: 00000000080daf1c RDI: 00000000080f12a0 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 Allocated by task 13761: save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59 save_stack+0x43/0xd0 mm/kasan/kasan.c:447 set_track mm/kasan/kasan.c:459 [inline] kasan_kmalloc+0xc7/0xe0 mm/kasan/kasan.c:551 __do_kmalloc mm/slab.c:3725 [inline] __kmalloc_track_caller+0x143/0x7a0 mm/slab.c:3740 kstrndup+0x3c/0xc0 mm/util.c:98 uinput_dev_setup+0x1d1/0x330 drivers/input/misc/uinput.c:416 uinput_ioctl_handler.isra.10+0x10f1/0x1c10 drivers/input/misc/uinput.c:825 uinput_compat_ioctl+0x47/0x70 drivers/input/misc/uinput.c:1001 C_SYSC_ioctl fs/compat_ioctl.c:1595 [inline] compat_SyS_ioctl+0x148/0x2c90 fs/compat_ioctl.c:1542 do_syscall_32_irqs_on arch/x86/entry/common.c:326 [inline] do_fast_syscall_32+0x3cb/0xd95 arch/x86/entry/common.c:388 entry_SYSENTER_compat+0x51/0x60 arch/x86/entry/entry_64_compat.S:124 Freed by task 13761: save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59 save_stack+0x43/0xd0 mm/kasan/kasan.c:447 set_track mm/kasan/kasan.c:459 [inline] kasan_slab_free+0x71/0xc0 mm/kasan/kasan.c:524 __cache_free mm/slab.c:3503 [inline] kfree+0xcc/0x270 mm/slab.c:3820 uinput_destroy_device+0xd0/0x1f0 drivers/input/misc/uinput.c:250 uinput_ioctl_handler.isra.10+0x110b/0x1c10 drivers/input/misc/uinput.c:821 uinput_compat_ioctl+0x47/0x70 drivers/input/misc/uinput.c:1001 C_SYSC_ioctl fs/compat_ioctl.c:1595 [inline] compat_SyS_ioctl+0x148/0x2c90 fs/compat_ioctl.c:1542 do_syscall_32_irqs_on arch/x86/entry/common.c:326 [inline] do_fast_syscall_32+0x3cb/0xd95 arch/x86/entry/common.c:388 entry_SYSENTER_compat+0x51/0x60 arch/x86/entry/entry_64_compat.S:124 The buggy address belongs to the object at ffff88011e55df40 which belongs to the cache kmalloc-32 of size 32 The buggy address is located 0 bytes inside of 32-byte region [ffff88011e55df40, ffff88011e55df60) The buggy address belongs to the page: page:ffffea0004795740 count:1 mapcount:0 mapping:ffff88011e55d000 index:0xffff88011e55dfc1 flags: 0x2fffc0000000100(slab) raw: 02fffc0000000100 ffff88011e55d000 ffff88011e55dfc1 000000010000002d raw: ffffea000479b760 ffffea00045b2da0 ffff88012bc001c0 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88011e55de00: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc ffff88011e55de80: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc >ffff88011e55df00: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc ^ ffff88011e55df80: fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc ffff88011e55e000: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb ==================================================================