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BUG: KMSAN: kernel-infoleak in _copy_to_user+0x1a4/0x250 lib/usercopy.c:32
CPU: 0 PID: 6254 Comm: syz-executor456 Not tainted 4.20.0-rc5+ #2
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+0x1c9/0x220 lib/dump_stack.c:113
 kmsan_report+0x12d/0x290 mm/kmsan/kmsan.c:682
 kmsan_internal_check_memory+0x334/0xa60 mm/kmsan/kmsan.c:742
 kmsan_copy_to_user+0x8d/0xa0 mm/kmsan/kmsan_hooks.c:604
 _copy_to_user+0x1a4/0x250 lib/usercopy.c:32
 copy_to_user include/linux/uaccess.h:177 [inline]
 video_usercopy+0x16c9/0x17d0 drivers/media/v4l2-core/v4l2-ioctl.c:3066
 video_ioctl2+0x9f/0xb0 drivers/media/v4l2-core/v4l2-ioctl.c:3079
 v4l2_ioctl+0x23f/0x270 drivers/media/v4l2-core/v4l2-dev.c:364
 do_vfs_ioctl+0xf36/0x2d30 fs/ioctl.c:46
 ksys_ioctl fs/ioctl.c:713 [inline]
 __do_sys_ioctl fs/ioctl.c:720 [inline]
 __se_sys_ioctl+0x1da/0x270 fs/ioctl.c:718
 __x64_sys_ioctl+0x4a/0x70 fs/ioctl.c:718
 do_syscall_64+0xcd/0x110 arch/x86/entry/common.c:291
 entry_SYSCALL_64_after_hwframe+0x63/0xe7
RIP: 0033:0x445659
Code: e8 6c b6 02 00 48 83 c4 18 c3 0f 1f 80 00 00 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 0f 83 2b 12 fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007ff7a472ada8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00000000006dac28 RCX: 0000000000445659
RDX: 0000000020000000 RSI: 0000000080885659 RDI: 0000000000000003
RBP: 00000000006dac20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006dac2c
R13: 6469762f7665642f R14: 00007ff7a472b9c0 R15: 00000000006dad2c

Uninit was stored to memory at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:247 [inline]
 kmsan_save_stack mm/kmsan/kmsan.c:262 [inline]
 kmsan_internal_chain_origin+0x162/0x260 mm/kmsan/kmsan.c:470
 kmsan_memcpy_memmove_metadata+0x1a9/0xf30 mm/kmsan/kmsan.c:345
 kmsan_memcpy_metadata+0xb/0x10 mm/kmsan/kmsan.c:363
 __msan_memcpy+0x61/0x70 mm/kmsan/kmsan_instr.c:148
 __v4l2_event_dequeue+0x2f8/0x730 drivers/media/v4l2-core/v4l2-event.c:54
 v4l2_event_dequeue+0x41c/0x560 drivers/media/v4l2-core/v4l2-event.c:81
 v4l_dqevent+0xba/0xe0 drivers/media/v4l2-core/v4l2-ioctl.c:2427
 __video_do_ioctl+0x1975/0x1fc0 drivers/media/v4l2-core/v4l2-ioctl.c:2853
 video_usercopy+0x8ae/0x17d0 drivers/media/v4l2-core/v4l2-ioctl.c:3035
 video_ioctl2+0x9f/0xb0 drivers/media/v4l2-core/v4l2-ioctl.c:3079
 v4l2_ioctl+0x23f/0x270 drivers/media/v4l2-core/v4l2-dev.c:364
 do_vfs_ioctl+0xf36/0x2d30 fs/ioctl.c:46
 ksys_ioctl fs/ioctl.c:713 [inline]
 __do_sys_ioctl fs/ioctl.c:720 [inline]
 __se_sys_ioctl+0x1da/0x270 fs/ioctl.c:718
 __x64_sys_ioctl+0x4a/0x70 fs/ioctl.c:718
 do_syscall_64+0xcd/0x110 arch/x86/entry/common.c:291
 entry_SYSCALL_64_after_hwframe+0x63/0xe7

Uninit was stored to memory at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:247 [inline]
 kmsan_save_stack mm/kmsan/kmsan.c:262 [inline]
 kmsan_internal_chain_origin+0x162/0x260 mm/kmsan/kmsan.c:470
 kmsan_memcpy_memmove_metadata+0x1a9/0xf30 mm/kmsan/kmsan.c:345
 kmsan_memcpy_metadata+0xb/0x10 mm/kmsan/kmsan.c:363
 __msan_memcpy+0x61/0x70 mm/kmsan/kmsan_instr.c:148
 __v4l2_event_queue_fh+0xd2d/0x1260 drivers/media/v4l2-core/v4l2-event.c:145
 v4l2_event_queue_fh+0x1a1/0x270 drivers/media/v4l2-core/v4l2-event.c:185
 v4l2_ctrl_add_event+0x952/0xc20 drivers/media/v4l2-core/v4l2-ctrls.c:4099
 v4l2_event_subscribe+0xf75/0x1240 drivers/media/v4l2-core/v4l2-event.c:251
 v4l2_ctrl_subscribe_event+0xb6/0x110 drivers/media/v4l2-core/v4l2-ctrls.c:4156
 v4l_subscribe_event+0x9e/0xc0 drivers/media/v4l2-core/v4l2-ioctl.c:2433
 __video_do_ioctl+0x1975/0x1fc0 drivers/media/v4l2-core/v4l2-ioctl.c:2853
 video_usercopy+0x8ae/0x17d0 drivers/media/v4l2-core/v4l2-ioctl.c:3035
 video_ioctl2+0x9f/0xb0 drivers/media/v4l2-core/v4l2-ioctl.c:3079
 v4l2_ioctl+0x23f/0x270 drivers/media/v4l2-core/v4l2-dev.c:364
 do_vfs_ioctl+0xf36/0x2d30 fs/ioctl.c:46
 ksys_ioctl fs/ioctl.c:713 [inline]
 __do_sys_ioctl fs/ioctl.c:720 [inline]
 __se_sys_ioctl+0x1da/0x270 fs/ioctl.c:718
 __x64_sys_ioctl+0x4a/0x70 fs/ioctl.c:718
 do_syscall_64+0xcd/0x110 arch/x86/entry/common.c:291
 entry_SYSCALL_64_after_hwframe+0x63/0xe7

Local variable description: ----ev@v4l2_ctrl_add_event
Variable was created at:
 v4l2_ctrl_add_event+0x6e/0xc20 drivers/media/v4l2-core/v4l2-ctrls.c:4080
 v4l2_event_subscribe+0xf75/0x1240 drivers/media/v4l2-core/v4l2-event.c:251

Bytes 44-71 of 136 are uninitialized
Memory access of size 136 starts at ffff8881bcc903c0
Data copied to user address 0000000020000000
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