r5848: Fix inherit owner to chown directories in a porable and secure way (from

just secure on Linux). Idea from tridge.
Jeremy.

diff --git a/source/smbd/open.c b/source/smbd/open.c
index 3124526c7efd973afe43bd55a14ed5371f0b0671..79c27388dc7e37b69cfa5c6fd930e4b1700ef784 100644 (file)
--- a/source/smbd/open.c
+++ b/source/smbd/open.c
@@ -115,67 +115,55 @@ Error was %s\n",
 
        } else {
                /* We've already done an lstat into psbuf, and we know it's a directory. If
-                  we can do an open/fstat and the dev/ino are the same then we can safely
-                  fchown without races. This works under Linux - but should just fail gracefully
-                  if any step on the way fails. JRA */
+                  we can cd into the directory and the dev/ino are the same then we can safely
+                  chown without races as we're locking the directory in place by being in it.
+                  This should work on any UNIX (thanks tridge :-). JRA.
+               */
 
-               BOOL need_close_fsp = False;
+               pstring saved_dir;
                SMB_STRUCT_STAT sbuf;
-               int fd = -1;
-
-               if (!fsp) {
-                       int action;
-                       fsp = open_directory(conn, fname, psbuf, FILE_GENERIC_READ,
-                                       SET_DENY_MODE(DENY_NONE)|SET_OPEN_MODE(DOS_OPEN_RDONLY),
-                                       FILE_EXISTS_OPEN, &action);
-                       if (!fsp) {
-                               DEBUG(10,("change_owner_to_parent: open_directory on %s failed. Error was %s\n",
-                                       fname, strerror(errno) ));
-                               return;
-                       }
-                       need_close_fsp = True;
-               } 
-               fd = SMB_VFS_OPEN(conn,fname,O_RDONLY,0);
-               if (fd == -1) {
-                       DEBUG(10,("change_owner_to_parent: failed to VFS_OPEN directory %s. Error was %s\n",
-                               fname, strerror(errno) ));
+
+               if (!vfs_GetWd(conn,saved_dir)) {
+                       DEBUG(0,("change_owner_to_parent: failed to get current working directory\n"));
+                       return;
+               }
+
+               /* Chdir into the new path. */
+               if (vfs_ChDir(conn, fname) == -1) {
+                       DEBUG(0,("change_owner_to_parent: failed to change current working directory to %s. \
+Error was %s\n", fname, strerror(errno) ));
                        goto out;
                }
-               ret = SMB_VFS_FSTAT(fsp,fd,&sbuf);
-               if (ret == -1) {
-                       DEBUG(10,("change_owner_to_parent: failed to VFS_STAT directory %s. Error was %s\n",
-                               fname, strerror(errno) ));
+
+               if (SMB_VFS_STAT(conn,".",&sbuf) == -1) {
+                       DEBUG(0,("change_owner_to_parent: failed to stat directory '.' (%s) \
+Error was %s\n", fname, strerror(errno)));
                        goto out;
                }
 
                /* Ensure we're pointing at the same place. */
-               if (sbuf.st_dev != psbuf->st_dev || sbuf.st_ino != psbuf->st_ino || !S_ISDIR(sbuf.st_mode)) {
-                       DEBUG(0,("change_owner_to_parent: device/inode/mode on director %s changed. Refusing to fchown !\n",
+               if (sbuf.st_dev != psbuf->st_dev || sbuf.st_ino != psbuf->st_ino || sbuf.st_mode != psbuf->st_mode ) {
+                       DEBUG(0,("change_owner_to_parent: device/inode/mode on directory %s changed. Refusing to chown !\n",
                                fname ));
                        goto out;
                }
 
                become_root();
-               ret = SMB_VFS_FCHOWN(fsp, fd, parent_st.st_uid, (gid_t)-1);
+               ret = SMB_VFS_CHOWN(conn, ".", parent_st.st_uid, (gid_t)-1);
                unbecome_root();
                if (ret == -1) {
-                       DEBUG(10,("change_owner_to_parent: failed to fchown directory %s to parent directory uid %u. \
+                       DEBUG(10,("change_owner_to_parent: failed to chown directory %s to parent directory uid %u. \
 Error was %s\n",
                                fname, (unsigned int)parent_st.st_uid, strerror(errno) ));
                        goto out;
                }
 
-               DEBUG(10,("change_owner_to_parent: changed new directory %s to parent directory uid %u.\n",
+               DEBUG(10,("change_owner_to_parent: changed ownership of new directory %s to parent directory uid %u.\n",
                        fname, (unsigned int)parent_st.st_uid ));
 
   out:
 
-               if (fd != -1) {
-                       SMB_VFS_CLOSE(fsp,fd);
-               }
-               if (need_close_fsp) {
-                       close_file(fsp, False);
-               }
+               vfs_ChDir(conn,saved_dir);
        }
 }