i2c: validate user data in compat ioctl

stable inclusion
from stable-v5.10.90
commit 8d31cbab4c295d7010ebb729e9d02d0e9cece18f
bugzilla: 186168 https://gitee.com/openeuler/kernel/issues/I4SHY1

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=8d31cbab4c295d7010ebb729e9d02d0e9cece18f

--------------------------------

[ Upstream commit bb436283 ]

Wrong user data may cause warning in i2c_transfer(), ex: zero msgs.
Userspace should not be able to trigger warnings, so this patch adds
validation checks for user data in compact ioctl to prevent reported
warnings

Reported-and-tested-by: syzbot+e417648b303855b91d8a@syzkaller.appspotmail.com
Fixes: 7d5cb456 ("i2c compat ioctls: move to ->compat_ioctl()")
Signed-off-by: NPavel Skripkin <paskripkin@gmail.com>
Signed-off-by: NWolfram Sang <wsa@kernel.org>
Signed-off-by: NSasha Levin <sashal@kernel.org>
Signed-off-by: NChen Jun <chenjun102@huawei.com>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>

drivers/i2c/i2c-dev.c

@@ -536,6 +536,9 @@ static long compat_i2cdev_ioctl(struct file *file, unsigned int cmd, unsigned lo
 				   sizeof(rdwr_arg)))
 			return -EFAULT;
 
+		if (!rdwr_arg.msgs || rdwr_arg.nmsgs == 0)
+			return -EINVAL;
+
 		if (rdwr_arg.nmsgs > I2C_RDWR_IOCTL_MAX_MSGS)
 			return -EINVAL;