smb: Allow renaming a file to the same name with a different casegnome-42

We check to see if the desired file name already exists before doing
a renaming by stat'ing the file (to prevent smb from destroying an
existing file).  Since smb is not case sensitive, the check for an
existing file mistakenly returns true if we are only changing the
filename's case.

Add a second check to see whether we are simply changing the
case of the filename.

Fixes: https://gitlab.gnome.org/GNOME/gvfs/-/issues/672


(cherry picked from commit a845ba0220fef72815ce091b92f74767d8025541)

1 files changed, 21 insertions, 10 deletions

diff --git a/daemon/gvfsbackendsmb.c b/daemon/gvfsbackendsmb.c
index d999a2a6..87cb2cae 100644
--- a/daemon/gvfsbackendsmb.c
+++ b/daemon/gvfsbackendsmb.c
@@ -1892,6 +1892,9 @@ do_set_display_name (GVfsBackend *backend,
 {
   GVfsBackendSmb *op_backend = G_VFS_BACKEND_SMB (backend);
   char *from_uri, *to_uri;
+  g_autofree char *basename = NULL;
+  g_autofree char *old_name_case = NULL;
+  g_autofree char *new_name_case = NULL;
   char *dirname, *new_path;
   int res, errsv;
   struct stat st;
@@ -1899,6 +1902,7 @@ do_set_display_name (GVfsBackend *backend,
   smbc_stat_fn smbc_stat;
 
   dirname = g_path_get_dirname (filename);
+  basename = g_path_get_basename (filename);
 
   /* TODO: display name is in utf8, atm we assume libsmb uris
      are in utf8, but this might not be true if the user changed
@@ -1910,18 +1914,25 @@ do_set_display_name (GVfsBackend *backend,
   from_uri = create_smb_uri (op_backend->server, op_backend->port, op_backend->share, filename);
   to_uri = create_smb_uri (op_backend->server, op_backend->port, op_backend->share, new_path);
   
-
-  /* We can't rely on libsmbclient reporting EEXIST, let's always stat first.
-   * https://bugzilla.gnome.org/show_bug.cgi?id=616645
+  /* If we are simply changing the case of an existing file, we don't need to
+   * worry about overwriting another file.
    */
-  smbc_stat = smbc_getFunctionStat (op_backend->smb_context);
-  res = smbc_stat (op_backend->smb_context, to_uri, &st);
-  if (res == 0)
+  old_name_case = g_utf8_casefold (basename, -1);
+  new_name_case = g_utf8_casefold (display_name, -1);
+  if (g_strcmp0 (old_name_case, new_name_case) != 0)
     {
-      g_vfs_job_failed (G_VFS_JOB (job),
-                        G_IO_ERROR, G_IO_ERROR_EXISTS,
-                        _("Can’t rename file, filename already exists"));
-      goto out;
+      /* We can't rely on libsmbclient reporting EEXIST, let's always stat first.
+       * https://bugzilla.gnome.org/show_bug.cgi?id=616645
+       */
+      smbc_stat = smbc_getFunctionStat (op_backend->smb_context);
+      res = smbc_stat (op_backend->smb_context, to_uri, &st);
+      if (res == 0)
+        {
+          g_vfs_job_failed (G_VFS_JOB (job),
+                            G_IO_ERROR, G_IO_ERROR_EXISTS,
+                            _("Can’t rename file, filename already exists"));
+          goto out;
+        }
     }
 
   smbc_rename = smbc_getFunctionRename (op_backend->smb_context);