[syzbot] [media?] KMSAN: uninit-value in cxusb_i2c_xfer

[syzbot <syzbot+526bd95c0ec629993bf3@syzkaller.appspotmail.com>]

Hello,

syzbot found the following issue on:

HEAD commit:    4e82c87058f4 Merge tag 'rust-6.15' of git://git.kernel.org..
git tree:       upstream
console+strace: https://syzkaller.appspot.com/x/log.txt?x=166a7bcf980000
kernel config:  https://syzkaller.appspot.com/x/.config?x=378acbc45ac948ee
dashboard link: https://syzkaller.appspot.com/bug?extid=526bd95c0ec629993bf3
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=13488fb0580000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=1595dc74580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/6045aa9da8ac/disk-4e82c870.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1adf8802c9fe/vmlinux-4e82c870.xz
kernel image: https://storage.googleapis.com/syzbot-assets/9eb6c71670e3/bzImage-4e82c870.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+526bd95c0ec629993bf3@syzkaller.appspotmail.com

dvb-usb: bulk message failed: -22 (3/0)
=====================================================
BUG: KMSAN: uninit-value in cxusb_gpio_tuner drivers/media/usb/dvb-usb/cxusb.c:124 [inline]
BUG: KMSAN: uninit-value in cxusb_i2c_xfer+0x153a/0x1a60 drivers/media/usb/dvb-usb/cxusb.c:196
 cxusb_gpio_tuner drivers/media/usb/dvb-usb/cxusb.c:124 [inline]
 cxusb_i2c_xfer+0x153a/0x1a60 drivers/media/usb/dvb-usb/cxusb.c:196
 __i2c_transfer+0xe25/0x3150 drivers/i2c/i2c-core-base.c:-1
 i2c_transfer+0x317/0x4a0 drivers/i2c/i2c-core-base.c:2315
 i2c_transfer_buffer_flags+0x125/0x1e0 drivers/i2c/i2c-core-base.c:2343
 i2c_master_send include/linux/i2c.h:109 [inline]
 i2cdev_write+0x210/0x280 drivers/i2c/i2c-dev.c:183
 do_loop_readv_writev fs/read_write.c:848 [inline]
 vfs_writev+0x963/0x14e0 fs/read_write.c:1057
 do_writev+0x247/0x5c0 fs/read_write.c:1101
 __do_sys_writev fs/read_write.c:1169 [inline]
 __se_sys_writev fs/read_write.c:1166 [inline]
 __x64_sys_writev+0x98/0xe0 fs/read_write.c:1166
 x64_sys_call+0x2229/0x3c80 arch/x86/include/generated/asm/syscalls_64.h:21
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x1e0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Local variable i.i809 created at:
 cxusb_gpio_tuner drivers/media/usb/dvb-usb/cxusb.c:116 [inline]
 cxusb_i2c_xfer+0x323/0x1a60 drivers/media/usb/dvb-usb/cxusb.c:196
 __i2c_transfer+0xe25/0x3150 drivers/i2c/i2c-core-base.c:-1

CPU: 0 UID: 0 PID: 5806 Comm: syz-executor225 Not tainted 6.14.0-syzkaller-10892-g4e82c87058f4 #0 PREEMPT(undef) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
=====================================================


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