[CIFS] undo changes in cifs_rename_pending_delete if it errors out

The cifs_rename_pending_delete process involves multiple steps. If it
fails and we're going to return error, we don't want to leave things in
a half-finished state. Add code to the function to undo changes if
a call fails.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>

1 files changed, 70 insertions, 32 deletions

diff --git a/fs/cifs/inode.c b/fs/cifs/inode.c
index dea9eeb58b00..232ab16d7fd4 100644
--- a/fs/cifs/inode.c
+++ b/fs/cifs/inode.c
@@ -773,16 +773,17 @@ out:
  * anything else.
  */
 static int
-cifs_rename_pending_delete(char *full_path, struct inode *inode, int xid)
+cifs_rename_pending_delete(char *full_path, struct dentry *dentry, int xid)
 {
         int oplock = 0;
         int rc;
         __u16 netfid;
+        struct inode *inode = dentry->d_inode;
         struct cifsInodeInfo *cifsInode = CIFS_I(inode);
         struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
         struct cifsTconInfo *tcon = cifs_sb->tcon;
-        __u32 dosattr;
-        FILE_BASIC_INFO *info_buf;
+        __u32 dosattr, origattr;
+        FILE_BASIC_INFO *info_buf = NULL;
 
         rc = CIFSSMBOpen(xid, tcon, full_path, FILE_OPEN,
                          DELETE|FILE_WRITE_ATTRIBUTES, CREATE_NOT_DIR,
@@ -791,50 +792,87 @@ cifs_rename_pending_delete(char *full_path, struct inode *inode, int xid)
         if (rc != 0)
                 goto out;
 
-        /* set ATTR_HIDDEN and clear ATTR_READONLY */
-        cifsInode = CIFS_I(inode);
-        dosattr = cifsInode->cifsAttrs & ~ATTR_READONLY;
+        origattr = cifsInode->cifsAttrs;
+        if (origattr == 0)
+                origattr |= ATTR_NORMAL;
+
+        dosattr = origattr & ~ATTR_READONLY;
         if (dosattr == 0)
                 dosattr |= ATTR_NORMAL;
         dosattr |= ATTR_HIDDEN;
 
-        info_buf = kzalloc(sizeof(*info_buf), GFP_KERNEL);
-        if (info_buf == NULL) {
-                rc = -ENOMEM;
-                goto out_close;
+        /* set ATTR_HIDDEN and clear ATTR_READONLY, but only if needed */
+        if (dosattr != origattr) {
+                info_buf = kzalloc(sizeof(*info_buf), GFP_KERNEL);
+                if (info_buf == NULL) {
+                        rc = -ENOMEM;
+                        goto out_close;
+                }
+                info_buf->Attributes = cpu_to_le32(dosattr);
+                rc = CIFSSMBSetFileInfo(xid, tcon, info_buf, netfid,
+                                        current->tgid);
+                /* although we would like to mark the file hidden
+                   if that fails we will still try to rename it */
+                if (rc != 0) {
+                        cifsInode->cifsAttrs = dosattr;
+                else
+                        dosattr = origattr; /* since not able to change them */
         }
-        info_buf->Attributes = cpu_to_le32(dosattr);
-        rc = CIFSSMBSetFileInfo(xid, tcon, info_buf, netfid, current->tgid);
-        kfree(info_buf);
-        if (rc != 0)
-                goto out_close;
-        cifsInode->cifsAttrs = dosattr;
 
         /* rename the file */
         rc = CIFSSMBRenameOpenFile(xid, tcon, netfid, NULL, cifs_sb->local_nls,
                                    cifs_sb->mnt_cifs_flags &
                                             CIFS_MOUNT_MAP_SPECIAL_CHR);
-        if (rc != 0)
-                goto out;
-
-        /* set DELETE_ON_CLOSE */
-        rc = CIFSSMBSetFileDisposition(xid, tcon, true, netfid, current->tgid);
+        if (rc != 0) {
+                rc = -ETXTBSY;
+                goto undo_setattr;
+        }
 
-        /*
-         * some samba versions return -ENOENT when we try to set the file
-         * disposition here. Likely a samba bug, but work around it for now.
-         * This means that some cifsXXX files may hang around after they
-         * shouldn't.
-         *
-         * BB: remove this once fixed samba servers are in the field
-         */
-        if (rc == -ENOENT)
-                rc = 0;
+        /* try to set DELETE_ON_CLOSE */
+        if (!cifsInode->delete_pending) {
+                rc = CIFSSMBSetFileDisposition(xid, tcon, true, netfid,
+                                               current->tgid);
+                /*
+                 * some samba versions return -ENOENT when we try to set the
+                 * file disposition here. Likely a samba bug, but work around
+                 * it for now. This means that some cifsXXX files may hang
+                 * around after they shouldn't.
+                 *
+                 * BB: remove this hack after more servers have the fix
+                 */
+                if (rc == -ENOENT)
+                        rc = 0;
+                else if (rc != 0) {
+                        rc = -ETXTBSY;
+                        goto undo_rename;
+                }
+                cifsInode->delete_pending = true;
+        }
 
 out_close:
         CIFSSMBClose(xid, tcon, netfid);
 out:
+        kfree(info_buf);
         return rc;
+
+        /*
+         * reset everything back to the original state. Don't bother
+         * dealing with errors here since we can't do anything about
+         * them anyway.
+         */
+undo_rename:
+        CIFSSMBRenameOpenFile(xid, tcon, netfid, dentry->d_name.name,
+                                cifs_sb->local_nls, cifs_sb->mnt_cifs_flags &
+                                            CIFS_MOUNT_MAP_SPECIAL_CHR);
+undo_setattr:
+        if (dosattr != origattr) {
+                info_buf->Attributes = cpu_to_le32(origattr);
+                if (!CIFSSMBSetFileInfo(xid, tcon, info_buf, netfid,
+                                        current->tgid))
+                        cifsInode->cifsAttrs = origattr;
+        }
+
+        goto out_close;
 }
 
 int cifs_unlink(struct inode *dir, struct dentry *dentry)
@@ -884,7 +922,7 @@ psx_del_no_retry:
         } else if (rc == -ENOENT) {
                 d_drop(dentry);
         } else if (rc == -ETXTBSY) {
-                rc = cifs_rename_pending_delete(full_path, inode, xid);
+                rc = cifs_rename_pending_delete(full_path, dentry, xid);
                 if (rc == 0)
                         drop_nlink(inode);
         } else if (rc == -EACCES && dosattr == 0) {