Always clear out these floppy_raw_cmd struct members after copying the entire structure from userspace so that the in-kernel version is always valid and never left in an interdeterminate state. drivers/block/floppy.c 6 1 files changed, 3 insertions, 3 deletions diff --git a/drivers/block/floppy.c b/drivers/block/floppy.c index 8f5565b..12251a6 100644 --- a/drivers/block/floppy.c +++ b/drivers/block/floppy.c @@ -3121,10 +3121,11 @@ loop: return -ENOMEM; *rcmd = ptr; ret = copy_from_user(ptr, param, sizeof(*ptr)); - if (ret) - return -EFAULT; ptr->next = NULL; ptr->buffer_length = 0; + ptr->kernel_data = NULL; + if (ret) + return -EFAULT; param += sizeof(struct floppy_raw_cmd); if (ptr->cmd_count > 33) /* the command may now also take up the space @@ -3140,7 +3141,6 @@ loop: for (i = 0; i < 16; i++) ptr->reply[i] = 0; ptr->resultcode = 0; - ptr->kernel_data = NULL; if (ptr->flags & (FD_RAW_READ | FD_RAW_WRITE)) { if (ptr->length <= 0)