===================================================== BUG: KMSAN: kernel-infoleak in kmsan_copy_to_user+0x81/0x90 mm/kmsan/kmsan_hooks.c:253 CPU: 0 PID: 16086 Comm: syz-executor.1 Not tainted 5.8.0-rc5-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+0x21c/0x280 lib/dump_stack.c:118 kmsan_report+0xf7/0x1e0 mm/kmsan/kmsan_report.c:121 kmsan_internal_check_memory+0x238/0x3d0 mm/kmsan/kmsan.c:423 kmsan_copy_to_user+0x81/0x90 mm/kmsan/kmsan_hooks.c:253 instrument_copy_to_user include/linux/instrumented.h:91 [inline] _copy_to_user+0x18e/0x260 lib/usercopy.c:33 copy_to_user include/linux/uaccess.h:170 [inline] video_put_user drivers/media/v4l2-core/v4l2-ioctl.c:3226 [inline] video_usercopy+0x24a9/0x3140 drivers/media/v4l2-core/v4l2-ioctl.c:3325 video_ioctl2+0x9f/0xb0 drivers/media/v4l2-core/v4l2-ioctl.c:3335 v4l2_ioctl+0x255/0x290 drivers/media/v4l2-core/v4l2-dev.c:360 native_ioctl drivers/media/v4l2-core/v4l2-compat-ioctl32.c:117 [inline] do_video_ioctl+0x9b8/0x14e70 drivers/media/v4l2-core/v4l2-compat-ioctl32.c:1668 v4l2_compat_ioctl32+0x2c0/0x370 drivers/media/v4l2-core/v4l2-compat-ioctl32.c:1790 __do_compat_sys_ioctl fs/ioctl.c:847 [inline] __se_compat_sys_ioctl+0x55f/0x1100 fs/ioctl.c:798 __ia32_compat_sys_ioctl+0x4a/0x70 fs/ioctl.c:798 do_syscall_32_irqs_on arch/x86/entry/common.c:430 [inline] __do_fast_syscall_32+0x2af/0x480 arch/x86/entry/common.c:477 do_fast_syscall_32+0x6b/0xd0 arch/x86/entry/common.c:505 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:554 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c RIP: 0023:0xf7f74549 Code: Bad RIP value. RSP: 002b:00000000f556e0cc EFLAGS: 00000296 ORIG_RAX: 0000000000000036 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00000000c0505609 RDX: 0000000020000180 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 Local variable ----vb32.i@video_usercopy created at: video_put_user drivers/media/v4l2-core/v4l2-ioctl.c:3210 [inline] video_usercopy+0x20d7/0x3140 drivers/media/v4l2-core/v4l2-ioctl.c:3325 video_put_user drivers/media/v4l2-core/v4l2-ioctl.c:3210 [inline] video_usercopy+0x20d7/0x3140 drivers/media/v4l2-core/v4l2-ioctl.c:3325 Bytes 52-55 of 80 are uninitialized Memory access of size 80 starts at ffff88803f043900 Data copied to user address 0000000020000180 =====================================================