cifs: make cifs_rename handle -EACCES errors
cifs: make cifs_rename handle -EACCES errors
Some servers seem to return -EACCES when attempting to rename one
open file on top of another. Refactor the cifs_rename logic to
attempt to rename the target file out of the way in this situation.
This also fixes the "unlink_target" logic to be undoable if the
subsequent rename fails.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
diff --git a/fs/cifs/inode.c b/fs/cifs/inode.c
index 23cca21..8ac4eab 100644
--- a/fs/cifs/inode.c
+++ b/fs/cifs/inode.c
@@ -1285,22 +1285,24 @@
return rc;
}
-int cifs_rename(struct inode *source_inode, struct dentry *source_direntry,
- struct inode *target_inode, struct dentry *target_direntry)
+int cifs_rename(struct inode *source_dir, struct dentry *source_dentry,
+ struct inode *target_dir, struct dentry *target_dentry)
{
char *fromName = NULL;
char *toName = NULL;
struct cifs_sb_info *cifs_sb_source;
struct cifs_sb_info *cifs_sb_target;
- struct cifsTconInfo *pTcon;
+ struct cifsTconInfo *tcon;
+ struct cifsInodeInfo *target_cinode;
FILE_UNIX_BASIC_INFO *info_buf_source = NULL;
FILE_UNIX_BASIC_INFO *info_buf_target;
- int xid;
- int rc;
+ __u16 dstfid;
+ int xid, rc, tmprc, oplock = 0;
+ bool delete_already_pending;
- cifs_sb_target = CIFS_SB(target_inode->i_sb);
- cifs_sb_source = CIFS_SB(source_inode->i_sb);
- pTcon = cifs_sb_source->tcon;
+ cifs_sb_target = CIFS_SB(target_dir->i_sb);
+ cifs_sb_source = CIFS_SB(source_dir->i_sb);
+ tcon = cifs_sb_source->tcon;
xid = GetXid();
@@ -1308,7 +1310,7 @@
* BB: this might be allowed if same server, but different share.
* Consider adding support for this
*/
- if (pTcon != cifs_sb_target->tcon) {
+ if (tcon != cifs_sb_target->tcon) {
rc = -EXDEV;
goto cifs_rename_exit;
}
@@ -1317,65 +1319,133 @@
* we already have the rename sem so we do not need to
* grab it again here to protect the path integrity
*/
- fromName = build_path_from_dentry(source_direntry);
+ fromName = build_path_from_dentry(source_dentry);
if (fromName == NULL) {
rc = -ENOMEM;
goto cifs_rename_exit;
}
- toName = build_path_from_dentry(target_direntry);
+ toName = build_path_from_dentry(target_dentry);
if (toName == NULL) {
rc = -ENOMEM;
goto cifs_rename_exit;
}
- rc = cifs_do_rename(xid, source_direntry, fromName,
- target_direntry, toName);
+ rc = cifs_do_rename(xid, source_dentry, fromName,
+ target_dentry, toName);
- if (rc == -EEXIST) {
- if (pTcon->unix_ext) {
- /*
- * Are src and dst hardlinks of same inode? We can
- * only tell with unix extensions enabled
- */
- info_buf_source =
- kmalloc(2 * sizeof(FILE_UNIX_BASIC_INFO),
- GFP_KERNEL);
- if (info_buf_source == NULL)
- goto unlink_target;
-
- info_buf_target = info_buf_source + 1;
- rc = CIFSSMBUnixQPathInfo(xid, pTcon, fromName,
- info_buf_source,
- cifs_sb_source->local_nls,
- cifs_sb_source->mnt_cifs_flags &
- CIFS_MOUNT_MAP_SPECIAL_CHR);
- if (rc != 0)
- goto unlink_target;
-
- rc = CIFSSMBUnixQPathInfo(xid, pTcon,
- toName, info_buf_target,
- cifs_sb_target->local_nls,
- /* remap based on source sb */
- cifs_sb_source->mnt_cifs_flags &
- CIFS_MOUNT_MAP_SPECIAL_CHR);
-
- if (rc == 0 && (info_buf_source->UniqueId ==
- info_buf_target->UniqueId))
- /* same file, POSIX says that this is a noop */
- goto cifs_rename_exit;
- } /* else ... BB we could add the same check for Windows by
- checking the UniqueId via FILE_INTERNAL_INFO */
-unlink_target:
+ if (rc == -EEXIST && tcon->unix_ext) {
/*
- * we either can not tell the files are hardlinked (as with
- * Windows servers) or files are not hardlinked. Delete the
- * target manually before renaming to follow POSIX rather than
- * Windows semantics
+ * Are src and dst hardlinks of same inode? We can
+ * only tell with unix extensions enabled
*/
- cifs_unlink(target_inode, target_direntry);
- rc = cifs_do_rename(xid, source_direntry, fromName,
- target_direntry, toName);
+ info_buf_source =
+ kmalloc(2 * sizeof(FILE_UNIX_BASIC_INFO),
+ GFP_KERNEL);
+ if (info_buf_source == NULL) {
+ rc = -ENOMEM;
+ goto cifs_rename_exit;
+ }
+
+ info_buf_target = info_buf_source + 1;
+ rc = CIFSSMBUnixQPathInfo(xid, tcon, fromName,
+ info_buf_source,
+ cifs_sb_source->local_nls,
+ cifs_sb_source->mnt_cifs_flags &
+ CIFS_MOUNT_MAP_SPECIAL_CHR);
+ if (rc != 0)
+ goto unlink_target;
+
+ rc = CIFSSMBUnixQPathInfo(xid, tcon,
+ toName, info_buf_target,
+ cifs_sb_target->local_nls,
+ /* remap based on source sb */
+ cifs_sb_source->mnt_cifs_flags &
+ CIFS_MOUNT_MAP_SPECIAL_CHR);
+
+ if (rc == 0 && (info_buf_source->UniqueId ==
+ info_buf_target->UniqueId))
+ /* same file, POSIX says that this is a noop */
+ goto cifs_rename_exit;
+
+ rc = -EEXIST;
+ } /* else ... BB we could add the same check for Windows by
+ checking the UniqueId via FILE_INTERNAL_INFO */
+
+ if ((rc == -EACCES) || (rc == -EEXIST)) {
+unlink_target:
+ /* don't bother if this is a negative dentry */
+ if (!target_dentry->d_inode)
+ goto cifs_rename_exit;
+
+ target_cinode = CIFS_I(target_dentry->d_inode);
+
+ /* try to move the target out of the way */
+ tmprc = CIFSSMBOpen(xid, tcon, toName, FILE_OPEN, DELETE,
+ CREATE_NOT_DIR, &dstfid, &oplock, NULL,
+ cifs_sb_target->local_nls,
+ cifs_sb_target->mnt_cifs_flags &
+ CIFS_MOUNT_MAP_SPECIAL_CHR);
+ if (tmprc)
+ goto cifs_rename_exit;
+
+ /* rename the file to random name */
+ tmprc = CIFSSMBRenameOpenFile(xid, tcon, dstfid, NULL,
+ cifs_sb_target->local_nls,
+ cifs_sb_target->mnt_cifs_flags &
+ CIFS_MOUNT_MAP_SPECIAL_CHR);
+
+ if (tmprc)
+ goto close_target;
+
+ delete_already_pending = target_cinode->delete_pending;
+
+ if (!delete_already_pending) {
+ /* set delete on close */
+ tmprc = CIFSSMBSetFileDisposition(xid, tcon,
+ true, dstfid,
+ current->tgid);
+ /*
+ * This hack is for broken samba servers, remove this
+ * once more fixed ones are in the field.
+ */
+ if (tmprc == -ENOENT)
+ delete_already_pending = false;
+ else if (tmprc)
+ goto undo_target_rename;
+
+ target_cinode->delete_pending = true;
+ }
+
+
+ rc = cifs_do_rename(xid, source_dentry, fromName,
+ target_dentry, toName);
+
+ if (rc == 0)
+ goto close_target;
+
+ /*
+ * after this point, we can't bother with error handling on
+ * the undo's. This is best effort since we can't do anything
+ * about failures here.
+ */
+ if (!delete_already_pending) {
+ tmprc = CIFSSMBSetFileDisposition(xid, tcon,
+ false, dstfid,
+ current->tgid);
+ if (tmprc == 0)
+ target_cinode->delete_pending = false;
+ }
+
+undo_target_rename:
+ /* rename failed: undo target rename */
+ CIFSSMBRenameOpenFile(xid, tcon, dstfid,
+ target_dentry->d_name.name,
+ cifs_sb_target->local_nls,
+ cifs_sb_target->mnt_cifs_flags &
+ CIFS_MOUNT_MAP_SPECIAL_CHR);
+close_target:
+ CIFSSMBClose(xid, tcon, dstfid);
}
cifs_rename_exit: