On Tue, 2019-07-30 at 16:40 +0800, Chuhong Yuan wrote: > strncpy(dest, src, strlen(src)) leads to unterminated > dest, which is dangerous. I don't buy that. The structure is only used for the TW_IOCTL_GET_COMPATIBILITY_INFO ioctl and all the fields for that are fixed width and are copied over as such. > Here driver_version's len is 32 and TW_DRIVER_VERSION > is shorter than 32. > Therefore strcpy is OK. The best practice for copying a string to a fixed width destination that does get printed within the kernel would be what the 3w-9xxx.c does strlcpy(tw_dev->tw_compat_info.driver_version, TW_DRIVER_VERSION, sizeof(tw_dev->tw_compat_info.driver_version)); But as I said, it doesn't really matter for a fixed width field that's never printed within the kernel. James
