Add both chroot worker and qemu side interfaces to create special files
(directory, device nodes, links and symbolic links)
Signed-off-by: M. Mohan Kumar <mo...@in.ibm.com>
---
hw/9pfs/virtio-9p-chroot-worker.c | 52 ++++++++++++++++++++
hw/9pfs/virtio-9p-chroot.c | 23 +++++++++
hw/9pfs/virtio-9p-chroot.h | 1 +
hw/9pfs/virtio-9p-local.c | 97 +++++++++++++++++++++++++------------
4 files changed, 142 insertions(+), 31 deletions(-)
diff --git a/hw/9pfs/virtio-9p-chroot-worker.c
b/hw/9pfs/virtio-9p-chroot-worker.c
index cdcb303..fcc0be1 100644
--- a/hw/9pfs/virtio-9p-chroot-worker.c
+++ b/hw/9pfs/virtio-9p-chroot-worker.c
@@ -115,6 +115,52 @@ unset_uid:
return fd;
}
+/*
+ * Create directory, symbolic link, link, device node and regular files
+ * Similar to create, but it does not return the fd of created object
+ * Returns 0 as file descriptor on success and -errno on failure
+ */
+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;
+}
+
static void chroot_daemonize(int chroot_sock)
{
sigset_t sigset;
@@ -210,6 +256,12 @@ int v9fs_chroot(FsContext *fs_ctx)
valid_fd = 1;
}
break;
+ case T_MKDIR:
+ case T_SYMLINK:
+ case T_LINK:
+ case T_MKNOD:
+ fd = chroot_do_create_special(&request);
+ break;
default:
fd = -1;
break;
diff --git a/hw/9pfs/virtio-9p-chroot.c b/hw/9pfs/virtio-9p-chroot.c
index 0c91db6..ff0a53e 100644
--- a/hw/9pfs/virtio-9p-chroot.c
+++ b/hw/9pfs/virtio-9p-chroot.c
@@ -102,3 +102,26 @@ unlock:
qemu_mutex_unlock(&fs_ctx->chroot_mutex);
return fd;
}
+
+/* Return 0 on success or -errno on error */
+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;
+}
diff --git a/hw/9pfs/virtio-9p-chroot.h b/hw/9pfs/virtio-9p-chroot.h
index 6f676e9..a7f60e2 100644
--- a/hw/9pfs/virtio-9p-chroot.h
+++ b/hw/9pfs/virtio-9p-chroot.h
@@ -40,5 +40,6 @@ typedef struct V9fsFileObjectRequest
int v9fs_chroot(FsContext *fs_ctx);
int v9fs_request(FsContext *fs_ctx, V9fsFileObjectRequest *or);
+int v9fs_create_special(FsContext *fs_ctx, V9fsFileObjectRequest *request);
#endif /* _QEMU_VIRTIO_9P_CHROOT_H */
diff --git a/hw/9pfs/virtio-9p-local.c b/hw/9pfs/virtio-9p-local.c
index aa8ebff..904ee71 100644
--- a/hw/9pfs/virtio-9p-local.c
+++ b/hw/9pfs/virtio-9p-local.c
@@ -83,6 +83,32 @@ static int passthrough_create(FsContext *fs_ctx, const char
*path, int flags,
return fd;
}
+static int passthrough_create_special(FsContext *fs_ctx, const char *oldpath,
+ const char *path, FsCred *credp, int type)
+{
+ V9fsFileObjectRequest request;
+ int retval;
+
+ retval = fill_fileobjectrequest(&request, path, credp);
+ if (retval < 0) {
+ return retval;
+ }
+ request.data.type = type;
+ if (oldpath) {
+ request.data.oldpath_len = strlen(oldpath);
+ if (strlen(oldpath) >= PATH_MAX) {
+ return -ENAMETOOLONG;
+ }
+ strcpy(request.path.old_path, oldpath);
+ }
+ retval = v9fs_create_special(fs_ctx, &request);
+ if (retval < 0) {
+ errno = -retval;
+ retval = -1;
+ }
+ return retval;
+}
+
static int local_lstat(FsContext *fs_ctx, const char *path, struct stat *stbuf)
{
int err;
@@ -300,8 +326,7 @@ static int local_mknod(FsContext *fs_ctx, const char *path,
FsCred *credp)
serrno = errno;
goto err_end;
}
- } else if ((fs_ctx->fs_sm == SM_PASSTHROUGH) ||
- (fs_ctx->fs_sm == SM_NONE)) {
+ } else if (fs_ctx->fs_sm == SM_NONE) {
err = mknod(rpath(fs_ctx, path), credp->fc_mode, credp->fc_rdev);
if (err == -1) {
return err;
@@ -311,6 +336,12 @@ static int local_mknod(FsContext *fs_ctx, const char
*path, FsCred *credp)
serrno = errno;
goto err_end;
}
+ } else if (fs_ctx->fs_sm == SM_PASSTHROUGH) {
+ err = passthrough_create_special(fs_ctx, NULL, path, credp, T_MKNOD);
+ if (err < 0) {
+ serrno = errno;
+ goto err_end;
+ }
}
return err;
@@ -337,8 +368,7 @@ static int local_mkdir(FsContext *fs_ctx, const char *path,
FsCred *credp)
serrno = errno;
goto err_end;
}
- } else if ((fs_ctx->fs_sm == SM_PASSTHROUGH) ||
- (fs_ctx->fs_sm == SM_NONE)) {
+ } else if (fs_ctx->fs_sm == SM_NONE) {
err = mkdir(rpath(fs_ctx, path), credp->fc_mode);
if (err == -1) {
return err;
@@ -348,6 +378,12 @@ static int local_mkdir(FsContext *fs_ctx, const char
*path, FsCred *credp)
serrno = errno;
goto err_end;
}
+ } else if (fs_ctx->fs_sm == SM_PASSTHROUGH) {
+ err = passthrough_create_special(fs_ctx, NULL, path, credp, T_MKDIR);
+ if (err < 0) {
+ serrno = errno;
+ goto err_end;
+ }
}
return err;
@@ -465,23 +501,19 @@ static int local_symlink(FsContext *fs_ctx, const char
*oldpath,
serrno = errno;
goto err_end;
}
- } else if ((fs_ctx->fs_sm == SM_PASSTHROUGH) ||
- (fs_ctx->fs_sm == SM_NONE)) {
+ } else if (fs_ctx->fs_sm == SM_NONE) {
err = symlink(oldpath, rpath(fs_ctx, newpath));
if (err) {
return err;
}
err = lchown(rpath(fs_ctx, newpath), credp->fc_uid, credp->fc_gid);
- if (err == -1) {
- /*
- * If we fail to change ownership and if we are
- * using security model none. Ignore the error
- */
- if (fs_ctx->fs_sm != SM_NONE) {
- serrno = errno;
- goto err_end;
- } else
- err = 0;
+ err = 0;
+ } else if (fs_ctx->fs_sm == SM_PASSTHROUGH) {
+ err = passthrough_create_special(fs_ctx, oldpath, newpath, credp,
+ T_SYMLINK);
+ if (err < 0) {
+ serrno = errno;
+ goto err_end;
}
}
return err;
@@ -492,24 +524,27 @@ err_end:
return err;
}
-static int local_link(FsContext *ctx, const char *oldpath, const char *newpath)
+static int local_link(FsContext *fs_ctx, const char *oldpath,
+ const char *newpath)
{
- char *tmp = qemu_strdup(rpath(ctx, oldpath));
int err, serrno = 0;
- if (tmp == NULL) {
- return -ENOMEM;
- }
-
- err = link(tmp, rpath(ctx, newpath));
- if (err == -1) {
- serrno = errno;
- }
-
- qemu_free(tmp);
-
- if (err == -1) {
- errno = serrno;
+ if (fs_ctx->fs_sm == SM_PASSTHROUGH) {
+ err = passthrough_create_special(fs_ctx, oldpath, newpath, NULL,
+ T_LINK);
+ if (err < 0) {
+ serrno = errno;
+ }
+ } else {
+ char *tmp = qemu_strdup(rpath(fs_ctx, oldpath));
+ if (tmp == NULL) {
+ return -ENOMEM;
+ }
+ err = link(tmp, rpath(fs_ctx, newpath));
+ if (err == -1) {
+ serrno = errno;
+ }
+ qemu_free(tmp);
}
return err;
--
1.7.3.4
