Merge remote-tracking branch 'remotes/gkurz/tags/for-upstream' into staging

Various bugfixes and code cleanups. Most notably, it fixes metadata handling in
mapped-file security mode (especially for the virtfs root).

# gpg: Signature made Tue 30 May 2017 14:36:22 BST
# gpg:                using DSA key 0x02FC3AEB0101DBC2
# gpg: Good signature from "Greg Kurz <groug@kaod.org>"
# gpg:                 aka "Greg Kurz <groug@free.fr>"
# gpg:                 aka "Greg Kurz <gkurz@linux.vnet.ibm.com>"
# gpg:                 aka "Gregory Kurz (Groug) <groug@free.fr>"
# gpg:                 aka "[jpeg image of size 3330]"
# gpg: WARNING: This key is not certified with a trusted signature!
# gpg:          There is no indication that the signature belongs to the owner.
# Primary key fingerprint: 2BD4 3B44 535E C0A7 9894  DBA2 02FC 3AEB 0101 DBC2

* remotes/gkurz/tags/for-upstream:
  9pfs: local: metadata file for the VirtFS root
  9pfs: local: simplify file opening
  9pfs: local: resolve special directories in paths
  9pfs: check return value of v9fs_co_name_to_path()
  util: drop old utimensat() compat code
  9pfs: assume utimensat() and futimens() are present
  fsdev: fix virtfs-proxy-helper cwd
  9pfs: local: fix unlink of alien files in mapped-file mode
  9pfs: drop pdu_push_and_notify()
  fsdev: don't allow unknown format in marshal/unmarshal
  virtio-9p/xen-9p: move 9p specific bits to core 9p code
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

configure

@@ -3629,25 +3629,6 @@ if compile_prog "" "" ; then
   inotify1=yes
 fi
 
-# check if utimensat and futimens are supported
-utimens=no
-cat > $TMPC << EOF
-#define _ATFILE_SOURCE
-#include <stddef.h>
-#include <fcntl.h>
-#include <sys/stat.h>
-
-int main(void)
-{
-    utimensat(AT_FDCWD, "foo", NULL, 0);
-    futimens(0, NULL);
-    return 0;
-}
-EOF
-if compile_prog "" "" ; then
-  utimens=yes
-fi
-
 # check if pipe2 is there
 pipe2=no
 cat > $TMPC << EOF
@@ -5434,9 +5415,6 @@ fi
 if test "$curses" = "yes" ; then
   echo "CONFIG_CURSES=y" >> $config_host_mak
 fi
-if test "$utimens" = "yes" ; then
-  echo "CONFIG_UTIMENSAT=y" >> $config_host_mak
-fi
 if test "$pipe2" = "yes" ; then
   echo "CONFIG_PIPE2=y" >> $config_host_mak
 fi

fsdev/9p-iov-marshal.c

@@ -168,7 +168,7 @@ ssize_t v9fs_iov_vunmarshal(struct iovec *out_sg, int out_num, size_t offset,
             break;
         }
         default:
-            break;
+            g_assert_not_reached();
         }
         if (copied < 0) {
             return copied;
@@ -281,7 +281,7 @@ ssize_t v9fs_iov_vmarshal(struct iovec *in_sg, int in_num, size_t offset,
             break;
         }
         default:
-            break;
+            g_assert_not_reached();
         }
         if (copied < 0) {
             return copied;

fsdev/virtfs-proxy-helper.c

@@ -945,7 +945,8 @@ static int process_requests(int sock)
                                      &spec[0].tv_sec, &spec[0].tv_nsec,
                                      &spec[1].tv_sec, &spec[1].tv_nsec);
             if (retval > 0) {
-                retval = qemu_utimens(path.data, spec);
+                retval = utimensat(AT_FDCWD, path.data, spec,
+                                   AT_SYMLINK_NOFOLLOW);
                 if (retval < 0) {
                     retval = -errno;
                 }
@@ -1129,14 +1130,14 @@ int main(int argc, char **argv)
         }
     }
 
-    if (chdir("/") < 0) {
-        do_perror("chdir");
-        goto error;
-    }
     if (chroot(rpath) < 0) {
         do_perror("chroot");
         goto error;
     }
+    if (chdir("/") < 0) {
+        do_perror("chdir");
+        goto error;
+    }
 
     get_version = false;
 #ifdef FS_IOC_GETVERSION

hw/9pfs/9p-handle.c

@@ -378,7 +378,6 @@ static int handle_utimensat(FsContext *ctx, V9fsPath *fs_path,
                             const struct timespec *buf)
 {
     int ret;
-#ifdef CONFIG_UTIMENSAT
     int fd;
     struct handle_data *data = (struct handle_data *)ctx->private;
 
@@ -388,10 +387,6 @@ static int handle_utimensat(FsContext *ctx, V9fsPath *fs_path,
     }
     ret = futimens(fd, buf);
     close(fd);
-#else
-    ret = -1;
-    errno = ENOSYS;
-#endif
     return ret;
 }
 

hw/9pfs/9p-local.c

@@ -53,13 +53,37 @@ int local_open_nofollow(FsContext *fs_ctx, const char *path, int flags,
                         mode_t mode)
 {
     LocalData *data = fs_ctx->private;
-
-    /* All paths are relative to the path data->mountfd points to */
-    while (*path == '/') {
-        path++;
+    int fd = data->mountfd;
+
+    while (*path && fd != -1) {
+        const char *c;
+        int next_fd;
+        char *head;
+
+        /* Only relative paths without consecutive slashes */
+        assert(*path != '/');
+
+        head = g_strdup(path);
+        c = strchrnul(path, '/');
+        if (*c) {
+            /* Intermediate path element */
+            head[c - path] = 0;
+            path = c + 1;
+            next_fd = openat_dir(fd, head);
+        } else {
+            /* Rightmost path element */
+            next_fd = openat_file(fd, head, flags, mode);
+            path = c;
+        }
+        g_free(head);
+        if (fd != data->mountfd) {
+            close_preserve_errno(fd);
+        }
+        fd = next_fd;
     }
 
-    return relative_openat_nofollow(data->mountfd, path, flags, mode);
+    assert(fd != data->mountfd);
+    return fd;
 }
 
 int local_opendir_nofollow(FsContext *fs_ctx, const char *path)
@@ -83,6 +107,7 @@ static void unlinkat_preserve_errno(int dirfd, const char *path, int flags)
 }
 
 #define VIRTFS_META_DIR ".virtfs_metadata"
+#define VIRTFS_META_ROOT_FILE VIRTFS_META_DIR "_root"
 
 static FILE *local_fopenat(int dirfd, const char *name, const char *mode)
 {
@@ -119,13 +144,17 @@ static void local_mapped_file_attr(int dirfd, const char *name,
     char buf[ATTR_MAX];
     int map_dirfd;
 
-    map_dirfd = openat_dir(dirfd, VIRTFS_META_DIR);
-    if (map_dirfd == -1) {
-        return;
-    }
+    if (strcmp(name, ".")) {
+        map_dirfd = openat_dir(dirfd, VIRTFS_META_DIR);
+        if (map_dirfd == -1) {
+            return;
+        }
 
-    fp = local_fopenat(map_dirfd, name, "r");
-    close_preserve_errno(map_dirfd);
+        fp = local_fopenat(map_dirfd, name, "r");
+        close_preserve_errno(map_dirfd);
+    } else {
+        fp = local_fopenat(dirfd, VIRTFS_META_ROOT_FILE, "r");
+    }
     if (!fp) {
         return;
     }
@@ -203,26 +232,38 @@ static int local_set_mapped_file_attrat(int dirfd, const char *name,
     int ret;
     char buf[ATTR_MAX];
     int uid = -1, gid = -1, mode = -1, rdev = -1;
-    int map_dirfd;
-
-    ret = mkdirat(dirfd, VIRTFS_META_DIR, 0700);
-    if (ret < 0 && errno != EEXIST) {
-        return -1;
-    }
-
-    map_dirfd = openat_dir(dirfd, VIRTFS_META_DIR);
-    if (map_dirfd == -1) {
-        return -1;
-    }
+    int map_dirfd = -1, map_fd;
+    bool is_root = !strcmp(name, ".");
+
+    if (is_root) {
+        fp = local_fopenat(dirfd, VIRTFS_META_ROOT_FILE, "r");
+        if (!fp) {
+            if (errno == ENOENT) {
+                goto update_map_file;
+            } else {
+                return -1;
+            }
+        }
+    } else {
+        ret = mkdirat(dirfd, VIRTFS_META_DIR, 0700);
+        if (ret < 0 && errno != EEXIST) {
+            return -1;
+        }
 
-    fp = local_fopenat(map_dirfd, name, "r");
-    if (!fp) {
-        if (errno == ENOENT) {
-            goto update_map_file;
-        } else {
-            close_preserve_errno(map_dirfd);
+        map_dirfd = openat_dir(dirfd, VIRTFS_META_DIR);
+        if (map_dirfd == -1) {
             return -1;
         }
+
+        fp = local_fopenat(map_dirfd, name, "r");
+        if (!fp) {
+            if (errno == ENOENT) {
+                goto update_map_file;
+            } else {
+                close_preserve_errno(map_dirfd);
+                return -1;
+            }
+        }
     }
     memset(buf, 0, ATTR_MAX);
     while (fgets(buf, ATTR_MAX, fp)) {
@@ -240,12 +281,26 @@ static int local_set_mapped_file_attrat(int dirfd, const char *name,
     fclose(fp);
 
 update_map_file:
-    fp = local_fopenat(map_dirfd, name, "w");
-    close_preserve_errno(map_dirfd);
+    if (is_root) {
+        fp = local_fopenat(dirfd, VIRTFS_META_ROOT_FILE, "w");
+    } else {
+        fp = local_fopenat(map_dirfd, name, "w");
+        /* We can't go this far with map_dirfd not being a valid file descriptor
+         * but some versions of gcc aren't smart enough to see it.
+         */
+        if (map_dirfd != -1) {
+            close_preserve_errno(map_dirfd);
+        }
+    }
     if (!fp) {
         return -1;
     }
 
+    map_fd = fileno(fp);
+    assert(map_fd != -1);
+    ret = fchmod(map_fd, 0600);
+    assert(ret == 0);
+
     if (credp->fc_uid != -1) {
         uid = credp->fc_uid;
     }
@@ -454,7 +509,8 @@ static off_t local_telldir(FsContext *ctx, V9fsFidOpenState *fs)
 
 static bool local_is_mapped_file_metadata(FsContext *fs_ctx, const char *name)
 {
-    return !strcmp(name, VIRTFS_META_DIR);
+    return
+        !strcmp(name, VIRTFS_META_DIR) || !strcmp(name, VIRTFS_META_ROOT_FILE);
 }
 
 static struct dirent *local_readdir(FsContext *ctx, V9fsFidOpenState *fs)
@@ -471,7 +527,7 @@ again:
         entry->d_type = DT_UNKNOWN;
     } else if (ctx->export_flags & V9FS_SM_MAPPED_FILE) {
         if (local_is_mapped_file_metadata(ctx, entry->d_name)) {
-            /* skip the meta data directory */
+            /* skip the meta data */
             goto again;
         }
         entry->d_type = DT_UNKNOWN;
@@ -992,6 +1048,14 @@ static int local_unlinkat_common(FsContext *ctx, int dirfd, const char *name,
     if (ctx->export_flags & V9FS_SM_MAPPED_FILE) {
         int map_dirfd;
 
+        /* We need to remove the metadata as well:
+         * - the metadata directory if we're removing a directory
+         * - the metadata file in the parent's metadata directory
+         *
+         * If any of these are missing (ie, ENOENT) then we're probably
+         * trying to remove something that wasn't created in mapped-file
+         * mode. We just ignore the error.
+         */
         if (flags == AT_REMOVEDIR) {
             int fd;
 
@@ -999,32 +1063,20 @@ static int local_unlinkat_common(FsContext *ctx, int dirfd, const char *name,
             if (fd == -1) {
                 goto err_out;
             }
-            /*
-             * If directory remove .virtfs_metadata contained in the
-             * directory
-             */
             ret = unlinkat(fd, VIRTFS_META_DIR, AT_REMOVEDIR);
             close_preserve_errno(fd);
             if (ret < 0 && errno != ENOENT) {
-                /*
-                 * We didn't had the .virtfs_metadata file. May be file created
-                 * in non-mapped mode ?. Ignore ENOENT.
-                 */
                 goto err_out;
             }
         }
-        /*
-         * Now remove the name from parent directory
-         * .virtfs_metadata directory.
-         */
         map_dirfd = openat_dir(dirfd, VIRTFS_META_DIR);
-        ret = unlinkat(map_dirfd, name, 0);
-        close_preserve_errno(map_dirfd);
-        if (ret < 0 && errno != ENOENT) {
-            /*
-             * We didn't had the .virtfs_metadata file. May be file created
-             * in non-mapped mode ?. Ignore ENOENT.
-             */
+        if (map_dirfd != -1) {
+            ret = unlinkat(map_dirfd, name, 0);
+            close_preserve_errno(map_dirfd);
+            if (ret < 0 && errno != ENOENT) {
+                goto err_out;
+            }
+        } else if (errno != ENOENT) {
             goto err_out;
         }
     }
@@ -1138,14 +1190,32 @@ static int local_name_to_path(FsContext *ctx, V9fsPath *dir_path,
     }
 
     if (dir_path) {
-        v9fs_path_sprintf(target, "%s/%s", dir_path->data, name);
-    } else if (strcmp(name, "/")) {
-        v9fs_path_sprintf(target, "%s", name);
+        if (!strcmp(name, ".")) {
+            /* "." relative to "foo/bar" is "foo/bar" */
+            v9fs_path_copy(target, dir_path);
+        } else if (!strcmp(name, "..")) {
+            if (!strcmp(dir_path->data, ".")) {
+                /* ".." relative to the root is "." */
+                v9fs_path_sprintf(target, ".");
+            } else {
+                char *tmp = g_path_get_dirname(dir_path->data);
+                /* Symbolic links are resolved by the client. We can assume
+                 * that ".." relative to "foo/bar" is equivalent to "foo"
+                 */
+                v9fs_path_sprintf(target, "%s", tmp);
+                g_free(tmp);
+            }
+        } else {
+            assert(!strchr(name, '/'));
+            v9fs_path_sprintf(target, "%s/%s", dir_path->data, name);
+        }
+    } else if (!strcmp(name, "/") || !strcmp(name, ".") ||
+               !strcmp(name, "..")) {
+            /* This is the root fid */
+        v9fs_path_sprintf(target, ".");
     } else {
-        /* We want the path of the export root to be relative, otherwise
-         * "*at()" syscalls would treat it as "/" in the host.
-         */
-        v9fs_path_sprintf(target, "%s", ".");
+        assert(!strchr(name, '/'));
+        v9fs_path_sprintf(target, "./%s", name);
     }
     return 0;
 }

hw/9pfs/9p-util.c

@@ -14,49 +14,6 @@
 #include "qemu/xattr.h"
 #include "9p-util.h"
 
-int relative_openat_nofollow(int dirfd, const char *path, int flags,
-                             mode_t mode)
-{
-    int fd;
-
-    fd = dup(dirfd);
-    if (fd == -1) {
-        return -1;
-    }
-
-    while (*path) {
-        const char *c;
-        int next_fd;
-        char *head;
-
-        /* Only relative paths without consecutive slashes */
-        assert(path[0] != '/');
-
-        head = g_strdup(path);
-        c = strchr(path, '/');
-        if (c) {
-            head[c - path] = 0;
-            next_fd = openat_dir(fd, head);
-        } else {
-            next_fd = openat_file(fd, head, flags, mode);
-        }
-        g_free(head);
-        if (next_fd == -1) {
-            close_preserve_errno(fd);
-            return -1;
-        }
-        close(fd);
-        fd = next_fd;
-
-        if (!c) {
-            break;
-        }
-        path = c + 1;
-    }
-
-    return fd;
-}
-
 ssize_t fgetxattrat_nofollow(int dirfd, const char *filename, const char *name,
                              void *value, size_t size)
 {

hw/9pfs/9p-util.h

@@ -50,8 +50,6 @@ static inline int openat_file(int dirfd, const char *name, int flags,
     return fd;
 }
 
-int relative_openat_nofollow(int dirfd, const char *path, int flags,
-                             mode_t mode);
 ssize_t fgetxattrat_nofollow(int dirfd, const char *path, const char *name,
                              void *value, size_t size);
 int fsetxattrat_nofollow(int dirfd, const char *path, const char *name,

hw/9pfs/9p.c

@@ -65,11 +65,6 @@ ssize_t pdu_unmarshal(V9fsPDU *pdu, size_t offset, const char *fmt, ...)
     return ret;
 }
 
-static void pdu_push_and_notify(V9fsPDU *pdu)
-{
-    pdu->s->transport->push_and_notify(pdu);
-}
-
 static int omode_to_uflags(int8_t mode)
 {
     int ret = 0;
@@ -668,7 +663,7 @@ static void coroutine_fn pdu_complete(V9fsPDU *pdu, ssize_t len)
     pdu->size = len;
     pdu->id = id;
 
-    pdu_push_and_notify(pdu);
+    pdu->s->transport->push_and_notify(pdu);
 
     /* Now wakeup anybody waiting in flush for this request */
     if (!qemu_co_queue_next(&pdu->complete)) {
@@ -2576,7 +2571,10 @@ static int coroutine_fn v9fs_complete_rename(V9fsPDU *pdu, V9fsFidState *fidp,
             err = -EINVAL;
             goto out;
         }
-        v9fs_co_name_to_path(pdu, &dirfidp->path, name->data, &new_path);
+        err = v9fs_co_name_to_path(pdu, &dirfidp->path, name->data, &new_path);
+        if (err < 0) {
+            goto out;
+        }
     } else {
         old_name = fidp->path.data;
         end = strrchr(old_name, '/');
@@ -2588,8 +2586,11 @@ static int coroutine_fn v9fs_complete_rename(V9fsPDU *pdu, V9fsFidState *fidp,
         new_name = g_malloc0(end - old_name + name->size + 1);
         strncat(new_name, old_name, end - old_name);
         strncat(new_name + (end - old_name), name->data, name->size);
-        v9fs_co_name_to_path(pdu, NULL, new_name, &new_path);
+        err = v9fs_co_name_to_path(pdu, NULL, new_name, &new_path);
         g_free(new_name);
+        if (err < 0) {
+            goto out;
+        }
     }
     err = v9fs_co_rename(pdu, &fidp->path, &new_path);
     if (err < 0) {
@@ -2669,20 +2670,26 @@ out_nofid:
     v9fs_string_free(&name);
 }
 
-static void coroutine_fn v9fs_fix_fid_paths(V9fsPDU *pdu, V9fsPath *olddir,
-                                            V9fsString *old_name,
-                                            V9fsPath *newdir,
-                                            V9fsString *new_name)
+static int coroutine_fn v9fs_fix_fid_paths(V9fsPDU *pdu, V9fsPath *olddir,
+                                           V9fsString *old_name,
+                                           V9fsPath *newdir,
+                                           V9fsString *new_name)
 {
     V9fsFidState *tfidp;
     V9fsPath oldpath, newpath;
     V9fsState *s = pdu->s;
-
+    int err;
 
     v9fs_path_init(&oldpath);
     v9fs_path_init(&newpath);
-    v9fs_co_name_to_path(pdu, olddir, old_name->data, &oldpath);
-    v9fs_co_name_to_path(pdu, newdir, new_name->data, &newpath);
+    err = v9fs_co_name_to_path(pdu, olddir, old_name->data, &oldpath);
+    if (err < 0) {
+        goto out;
+    }
+    err = v9fs_co_name_to_path(pdu, newdir, new_name->data, &newpath);
+    if (err < 0) {
+        goto out;
+    }
 
     /*
      * Fixup fid's pointing to the old name to
@@ -2694,8 +2701,10 @@ static void coroutine_fn v9fs_fix_fid_paths(V9fsPDU *pdu, V9fsPath *olddir,
             v9fs_fix_path(&tfidp->path, &newpath, strlen(oldpath.data));
         }
     }
+out:
     v9fs_path_free(&oldpath);
     v9fs_path_free(&newpath);
+    return err;
 }
 
 static int coroutine_fn v9fs_complete_renameat(V9fsPDU *pdu, int32_t olddirfid,
@@ -2729,8 +2738,8 @@ static int coroutine_fn v9fs_complete_renameat(V9fsPDU *pdu, int32_t olddirfid,
     }
     if (s->ctx.export_flags & V9FS_PATHNAME_FSCONTEXT) {
         /* Only for path based fid  we need to do the below fixup */
-        v9fs_fix_fid_paths(pdu, &olddirfidp->path, old_name,
-                           &newdirfidp->path, new_name);
+        err = v9fs_fix_fid_paths(pdu, &olddirfidp->path, old_name,
+                                 &newdirfidp->path, new_name);
     }
 out:
     if (olddirfidp) {
@@ -3446,12 +3455,16 @@ static inline bool is_read_only_op(V9fsPDU *pdu)
     }
 }
 
-void pdu_submit(V9fsPDU *pdu)
+void pdu_submit(V9fsPDU *pdu, P9MsgHeader *hdr)
 {
     Coroutine *co;
     CoroutineEntry *handler;
     V9fsState *s = pdu->s;
 
+    pdu->size = le32_to_cpu(hdr->size_le);
+    pdu->id = hdr->id;
+    pdu->tag = le16_to_cpu(hdr->tag_le);
+
     if (pdu->id >= ARRAY_SIZE(pdu_co_handlers) ||
         (pdu_co_handlers[pdu->id] == NULL)) {
         handler = v9fs_op_not_supp;
@@ -3462,6 +3475,8 @@ void pdu_submit(V9fsPDU *pdu)
     if (is_ro_export(&s->ctx) && !is_read_only_op(pdu)) {
         handler = v9fs_fs_ro;
     }
+
+    qemu_co_queue_init(&pdu->complete);
     co = qemu_coroutine_create(handler, pdu);
     qemu_coroutine_enter(co);
 }

hw/9pfs/9p.h

@@ -347,7 +347,7 @@ ssize_t pdu_marshal(V9fsPDU *pdu, size_t offset, const char *fmt, ...);
 ssize_t pdu_unmarshal(V9fsPDU *pdu, size_t offset, const char *fmt, ...);
 V9fsPDU *pdu_alloc(V9fsState *s);
 void pdu_free(V9fsPDU *pdu);
-void pdu_submit(V9fsPDU *pdu);
+void pdu_submit(V9fsPDU *pdu, P9MsgHeader *hdr);
 void v9fs_reset(V9fsState *s);
 
 struct V9fsTransport {

hw/9pfs/virtio-9p-device.c

@@ -70,13 +70,7 @@ static void handle_9p_output(VirtIODevice *vdev, VirtQueue *vq)
             goto out_free_req;
         }
 
-        pdu->size = le32_to_cpu(out.size_le);
-
-        pdu->id = out.id;
-        pdu->tag = le16_to_cpu(out.tag_le);
-
-        qemu_co_queue_init(&pdu->complete);
-        pdu_submit(pdu);
+        pdu_submit(pdu, &out);
     }
 
     return;

hw/9pfs/xen-9p-backend.c

@@ -243,14 +243,10 @@ static int xen_9pfs_receive(Xen9pfsRing *ring)
 
     /* cannot fail, because we only handle one request per ring at a time */
     pdu = pdu_alloc(&ring->priv->state);
-    pdu->size = le32_to_cpu(h.size_le);
-    pdu->id = h.id;
-    pdu->tag = le32_to_cpu(h.tag_le);
     ring->out_size = le32_to_cpu(h.size_le);
     ring->out_cons = cons + le32_to_cpu(h.size_le);
 
-    qemu_co_queue_init(&pdu->complete);
-    pdu_submit(pdu);
+    pdu_submit(pdu, &h);
 
     return 0;
 }

include/sysemu/os-posix.h

@@ -51,17 +51,6 @@ int os_mlock(void);
 typedef struct timeval qemu_timeval;
 #define qemu_gettimeofday(tp) gettimeofday(tp, NULL)
 
-#ifndef CONFIG_UTIMENSAT
-#ifndef UTIME_NOW
-# define UTIME_NOW     ((1l << 30) - 1l)
-#endif
-#ifndef UTIME_OMIT
-# define UTIME_OMIT    ((1l << 30) - 2l)
-#endif
-#endif
-typedef struct timespec qemu_timespec;
-int qemu_utimens(const char *path, const qemu_timespec *times);
-
 bool is_daemonized(void);
 
 /**

util/oslib-posix.c

@@ -207,53 +207,6 @@ int qemu_pipe(int pipefd[2])
     return ret;
 }
 
-int qemu_utimens(const char *path, const struct timespec *times)
-{
-    struct timeval tv[2], tv_now;
-    struct stat st;
-    int i;
-#ifdef CONFIG_UTIMENSAT
-    int ret;
-
-    ret = utimensat(AT_FDCWD, path, times, AT_SYMLINK_NOFOLLOW);
-    if (ret != -1 || errno != ENOSYS) {
-        return ret;
-    }
-#endif
-    /* Fallback: use utimes() instead of utimensat() */
-
-    /* happy if special cases */
-    if (times[0].tv_nsec == UTIME_OMIT && times[1].tv_nsec == UTIME_OMIT) {
-        return 0;
-    }
-    if (times[0].tv_nsec == UTIME_NOW && times[1].tv_nsec == UTIME_NOW) {
-        return utimes(path, NULL);
-    }
-
-    /* prepare for hard cases */
-    if (times[0].tv_nsec == UTIME_NOW || times[1].tv_nsec == UTIME_NOW) {
-        gettimeofday(&tv_now, NULL);
-    }
-    if (times[0].tv_nsec == UTIME_OMIT || times[1].tv_nsec == UTIME_OMIT) {
-        stat(path, &st);
-    }
-
-    for (i = 0; i < 2; i++) {
-        if (times[i].tv_nsec == UTIME_NOW) {
-            tv[i].tv_sec = tv_now.tv_sec;
-            tv[i].tv_usec = tv_now.tv_usec;
-        } else if (times[i].tv_nsec == UTIME_OMIT) {
-            tv[i].tv_sec = (i == 0) ? st.st_atime : st.st_mtime;
-            tv[i].tv_usec = 0;
-        } else {
-            tv[i].tv_sec = times[i].tv_sec;
-            tv[i].tv_usec = times[i].tv_nsec / 1000;
-        }
-    }
-
-    return utimes(path, &tv[0]);
-}
-
 char *
 qemu_get_local_state_pathname(const char *relative_pathname)
 {