=====================================================
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:906 [inline]
 __se_sys_ioctl+0x239/0x400 fs/ioctl.c:892
 __x64_sys_ioctl+0x97/0xe0 fs/ioctl.c:892
 x64_sys_call+0x1ebe/0x3db0 arch/x86/include/generated/asm/syscalls_64.h:17
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd9/0x1b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Uninit was stored to memory at:
------------[ cut here ]------------
WARNING: CPU: 1 PID: 9854 at kernel/stacktrace.c:29 stack_trace_print+0xd4/0xf0 kernel/stacktrace.c:29
Modules linked in:
CPU: 1 UID: 0 PID: 9854 Comm: syz.9.708 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
RIP: 0010:stack_trace_print+0xd4/0xf0 kernel/stacktrace.c:29
Code: 88 22 e0 91 89 de ba 20 00 00 00 4c 89 e1 e8 33 d5 4f ff 49 83 c6 08 49 ff cd 0f 85 6e ff ff ff eb 0b e8 2f e7 c0 00 eb d4 90 <0f> 0b 90 5b 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc cc 66 0f 1f
RSP: 0018:ffff88803bad3868 EFLAGS: 00010246
RAX: ffff888100300b58 RBX: 0000000000000000 RCX: 000007ffffffffff
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffff88803bad3890 R08: 0000000000000000 R09: 0000000000000000
R10: ffff88803b2d38a8 R11: 0000000000000001 R12: 0000000000000000
R13: 00000000abcd0100 R14: 0000000000000000 R15: 0000000000000000
FS:  00007f923ec516c0(0000) GS:ffff8881aabc5000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000559592480680 CR3: 0000000125806000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 000000000000000e DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 kmsan_print_origin+0xb0/0x340 mm/kmsan/report.c:133
 kmsan_report+0x1b8/0x2a0 mm/kmsan/report.c:196
 kmsan_internal_check_memory+0x496/0x570 mm/kmsan/core.c:330
 kmsan_copy_to_user+0xca/0xe0 mm/kmsan/hooks.c:271
 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:906 [inline]
 __se_sys_ioctl+0x239/0x400 fs/ioctl.c:892
 __x64_sys_ioctl+0x97/0xe0 fs/ioctl.c:892
 x64_sys_call+0x1ebe/0x3db0 arch/x86/include/generated/asm/syscalls_64.h:17
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd9/0x1b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f923dd8e969
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:00007f923ec51038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f923dfb5fa0 RCX: 00007f923dd8e969
RDX: 0000200000000140 RSI: 0000000000000720 RDI: 0000000000000007
RBP: 00007f923de10ab1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f923dfb5fa0 R15: 00007ffcf4bc2118
 </TASK>
---[ end trace 0000000000000000 ]---

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

Bytes 0-1 of 2 are uninitialized
Memory access of size 2 starts at ffff88803bad3d06
Data copied to user address 0000200000000080

CPU: 1 UID: 0 PID: 9854 Comm: syz.9.708 Tainted: G        W           6.15.0-rc3-syzkaller-00094-g02ddfb981de8 #0 PREEMPT(undef) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/29/2025
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