On Fri, Mar 4, 2011 at 9:25 AM, M. Mohan Kumar <mo...@in.ibm.com> wrote:
> +static int chroot_do_create_special(V9fsFileObjectRequest *request)
> +{
> + int cur_uid, cur_gid;
> + int retval = -1;
> +
> + cur_uid = geteuid();
> + cur_gid = getegid();
> +
> + if (setfsuid(request->data.uid) < 0) {
> + return -errno;
> + }
> + if (setfsgid(request->data.gid) < 0) {
> + retval = -errno;
> + goto unset_uid;
> + }
> +
> + switch (request->data.type) {
> + case T_MKDIR:
> + retval = mkdir(request->path.path, request->data.mode);
> + break;
> + case T_SYMLINK:
> + retval = symlink(request->path.old_path, request->path.path);
> + break;
> + case T_LINK:
> + retval = link(request->path.old_path, request->path.path);
> + break;
> + default:
> + retval = mknod(request->path.path, request->data.mode,
> + request->data.dev);
> + break;
> + }
> +
> + if (retval < 0) {
> + retval = -errno;
> + }
> + setfsgid(cur_gid);
> +unset_uid:
> + setfsuid(cur_uid);
> + return retval;
> +}
It would be nice to take this one step further and move file create
and open here too. The prototype we need is:
static int chroot_handle_request(V9fsFileObjectRequest *request, int *fd)
{
*fd = -1;
It returns 0 on success or -errno and *fd >= 0 if a file descriptor
was opened and -1 otherwise.
This function becomes the main request processing function called from
v9fs_chroot() and the switch statement there can be eliminated.
Sending the response back to QEMU then gets a cleaned up prototype:
chroot_sendfd(int chroot_sock, int result, int fd) where result is 0
on success or -errno and fd >= 0 if present or -1 if not.
> +int v9fs_create_special(FsContext *fs_ctx, V9fsFileObjectRequest *request)
> +{
> + int retval, sock_error;
> + qemu_mutex_lock(&fs_ctx->chroot_mutex);
> + if (fs_ctx->chroot_ioerror) {
> + retval = -EIO;
> + goto unlock;
> + }
> + if (v9fs_write_request(fs_ctx->chroot_socket, request) < 0) {
> + fs_ctx->chroot_ioerror = 1;
> + retval = -EIO;
> + goto unlock;
> + }
> + retval = v9fs_receivefd(fs_ctx->chroot_socket, &sock_error);
> + if (retval < 0 && sock_error) {
> + fs_ctx->chroot_ioerror = 1;
> + }
> +unlock:
> + qemu_mutex_unlock(&fs_ctx->chroot_mutex);
> + return retval;
> +}
This function is a duplicate of v9fs_request(). Can't there be just
one function?
Stefan
