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BUG: KMSAN: kernel-infoleak in instrument_copy_to_user include/linux/instrumented.h:114 [inline]
BUG: KMSAN: kernel-infoleak in _inline_copy_to_user include/linux/uaccess.h:196 [inline]
BUG: KMSAN: kernel-infoleak in _copy_to_user+0xcc/0x120 lib/usercopy.c:26
 instrument_copy_to_user include/linux/instrumented.h:114 [inline]
 _inline_copy_to_user include/linux/uaccess.h:196 [inline]
 _copy_to_user+0xcc/0x120 lib/usercopy.c:26
 copy_to_user include/linux/uaccess.h:225 [inline]
 i2cdev_ioctl_smbus+0x586/0x660 drivers/i2c/i2c-dev.c:394
 compat_i2cdev_ioctl+0x48f/0xb40 drivers/i2c/i2c-dev.c:585
 __do_compat_sys_ioctl fs/ioctl.c:1004 [inline]
 __se_compat_sys_ioctl fs/ioctl.c:947 [inline]
 __ia32_compat_sys_ioctl+0x7f6/0x1260 fs/ioctl.c:947
 ia32_sys_call+0x2d07/0x42c0 arch/x86/include/generated/asm/syscalls_32.h:55
 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline]
 __do_fast_syscall_32+0xb0/0x110 arch/x86/entry/syscall_32.c:306
 do_fast_syscall_32+0x38/0x80 arch/x86/entry/syscall_32.c:331
 do_SYSENTER_32+0x1f/0x30 arch/x86/entry/syscall_32.c:369
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e

Uninit was stored to memory at:
 i2c_smbus_xfer_emulated drivers/i2c/i2c-core-smbus.c:-1 [inline]
 __i2c_smbus_xfer+0x2561/0x2f60 drivers/i2c/i2c-core-smbus.c:607
 i2c_smbus_xfer+0x31d/0x4d0 drivers/i2c/i2c-core-smbus.c:545
 i2cdev_ioctl_smbus+0x4a1/0x660 drivers/i2c/i2c-dev.c:389
 compat_i2cdev_ioctl+0x48f/0xb40 drivers/i2c/i2c-dev.c:585
 __do_compat_sys_ioctl fs/ioctl.c:1004 [inline]
 __se_compat_sys_ioctl fs/ioctl.c:947 [inline]
 __ia32_compat_sys_ioctl+0x7f6/0x1260 fs/ioctl.c:947
 ia32_sys_call+0x2d07/0x42c0 arch/x86/include/generated/asm/syscalls_32.h:55
 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline]
 __do_fast_syscall_32+0xb0/0x110 arch/x86/entry/syscall_32.c:306
 do_fast_syscall_32+0x38/0x80 arch/x86/entry/syscall_32.c:331
 do_SYSENTER_32+0x1f/0x30 arch/x86/entry/syscall_32.c:369
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e

Local variable msgbuf1.i created at:
 i2c_smbus_xfer_emulated drivers/i2c/i2c-core-smbus.c:334 [inline]
 __i2c_smbus_xfer+0x86a/0x2f60 drivers/i2c/i2c-core-smbus.c:607
 i2c_smbus_xfer+0x31d/0x4d0 drivers/i2c/i2c-core-smbus.c:545

Byte 0 of 1 is uninitialized
Memory access of size 1 starts at ffff888073ef7c86
Data copied to user address 0000000080000080

CPU: 0 UID: 0 PID: 21613 Comm: syz.6.4198 Not tainted 6.15.0-rc3-syzkaller-00094-g02ddfb981de8 #0 PREEMPT(undef) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/29/2025
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