=====================================================
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
 i2cdev_ioctl+0xa14/0xf40 drivers/i2c/i2c-dev.c:478
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:597 [inline]
 __se_sys_ioctl+0x23c/0x400 fs/ioctl.c:583
 __x64_sys_ioctl+0x97/0xe0 fs/ioctl.c:583
 x64_sys_call+0x1cbc/0x3e30 arch/x86/include/generated/asm/syscalls_64.h:17
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd9/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Uninit was stored to memory at:
------------[ cut here ]------------
WARNING: CPU: 0 PID: 11957 at kernel/stacktrace.c:29 stack_trace_print+0xd4/0xf0 kernel/stacktrace.c:29
Modules linked in:
CPU: 0 UID: 0 PID: 11957 Comm: syz.7.2235 Not tainted syzkaller #0 PREEMPT(none) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:stack_trace_print+0xd4/0xf0 kernel/stacktrace.c:29
Code: b0 83 a0 91 89 de ba 20 00 00 00 4c 89 e1 e8 63 8f 4b ff 49 83 c6 08 49 ff cd 0f 85 6e ff ff ff eb 0b e8 7f 21 c7 00 eb d4 90 <0f> 0b 90 5b 41 5c 41 5d 41 5e 41 5f 5d e9 8a df a6 0e cc 66 0f 1f
RSP: 0018:ffff88811737b888 EFLAGS: 00010246
RAX: ffff8881159c2ca0 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffff88811737b8b0 R08: 0000000000000000 R09: 0000000000000000
R10: ffff888116b7b8c8 R11: 0000000000000001 R12: 0000000000000000
R13: 00000000abcd0100 R14: 0000000000000000 R15: 0000000000000000
FS:  00007f0656ff66c0(0000) GS:ffff8881aaf7a000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c46663d CR3: 000000012d99c000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 kmsan_print_origin+0xb0/0x340 mm/kmsan/report.c:133
 kmsan_report+0x1d3/0x320 mm/kmsan/report.c:196
 kmsan_internal_check_memory+0x1e1/0x230 mm/kmsan/core.c:327
 kmsan_copy_to_user+0xf1/0x190 mm/kmsan/hooks.c:269
 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
 i2cdev_ioctl+0xa14/0xf40 drivers/i2c/i2c-dev.c:478
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:597 [inline]
 __se_sys_ioctl+0x23c/0x400 fs/ioctl.c:583
 __x64_sys_ioctl+0x97/0xe0 fs/ioctl.c:583
 x64_sys_call+0x1cbc/0x3e30 arch/x86/include/generated/asm/syscalls_64.h:17
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd9/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f0658d8eec9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f0656ff6038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f0658fe5fa0 RCX: 00007f0658d8eec9
RDX: 0000200000000040 RSI: 0000000000000720 RDI: 0000000000000004
RBP: 00007f0658e11f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f0658fe6038 R14: 00007f0658fe5fa0 R15: 00007ffd298422e8
 </TASK>
---[ end trace 0000000000000000 ]---

Local variable msgbuf1.i created at:
 i2c_smbus_xfer_emulated drivers/i2c/i2c-core-smbus.c:335 [inline]
 __i2c_smbus_xfer+0x86a/0x2f60 drivers/i2c/i2c-core-smbus.c:608
 i2c_smbus_xfer+0x31d/0x4d0 drivers/i2c/i2c-core-smbus.c:546

Bytes 0-1 of 2 are uninitialized
Memory access of size 2 starts at ffff88811737bcf6
Data copied to user address 0000200000000340

CPU: 0 UID: 0 PID: 11957 Comm: syz.7.2235 Tainted: G        W           syzkaller #0 PREEMPT(none) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
=====================================================