X-Git-Url: http://plrg.eecs.uci.edu/git/?a=blobdiff_plain;f=fs%2Focfs2%2Fnamei.c;h=879f9f36b6073be477702e5cf66924dd00262e81;hb=f7a14f32e7e1e7e025d88e7b4c8e3cc99770f756;hp=2060fc398445a259d17167d43b97fed4ba7357ab;hpb=33c0022f0e687b0161a9bb84a5671df932551e3a;p=firefly-linux-kernel-4.4.55.git

diff --git a/fs/ocfs2/namei.c b/fs/ocfs2/namei.c
index 2060fc398445..879f9f36b607 100644
--- a/fs/ocfs2/namei.c
+++ b/fs/ocfs2/namei.c
@@ -991,6 +991,65 @@ leave:
 	return status;
 }
 
+static int ocfs2_check_if_ancestor(struct ocfs2_super *osb,
+		u64 src_inode_no, u64 dest_inode_no)
+{
+	int ret = 0, i = 0;
+	u64 parent_inode_no = 0;
+	u64 child_inode_no = src_inode_no;
+	struct inode *child_inode;
+
+#define MAX_LOOKUP_TIMES 32
+	while (1) {
+		child_inode = ocfs2_iget(osb, child_inode_no, 0, 0);
+		if (IS_ERR(child_inode)) {
+			ret = PTR_ERR(child_inode);
+			break;
+		}
+
+		ret = ocfs2_inode_lock(child_inode, NULL, 0);
+		if (ret < 0) {
+			iput(child_inode);
+			if (ret != -ENOENT)
+				mlog_errno(ret);
+			break;
+		}
+
+		ret = ocfs2_lookup_ino_from_name(child_inode, "..", 2,
+				&parent_inode_no);
+		ocfs2_inode_unlock(child_inode, 0);
+		iput(child_inode);
+		if (ret < 0) {
+			ret = -ENOENT;
+			break;
+		}
+
+		if (parent_inode_no == dest_inode_no) {
+			ret = 1;
+			break;
+		}
+
+		if (parent_inode_no == osb->root_inode->i_ino) {
+			ret = 0;
+			break;
+		}
+
+		child_inode_no = parent_inode_no;
+
+		if (++i >= MAX_LOOKUP_TIMES) {
+			mlog(ML_NOTICE, "max lookup times reached, filesystem "
+					"may have nested directories, "
+					"src inode: %llu, dest inode: %llu.\n",
+					(unsigned long long)src_inode_no,
+					(unsigned long long)dest_inode_no);
+			ret = 0;
+			break;
+		}
+	}
+
+	return ret;
+}
+
 /*
  * The only place this should be used is rename!
  * if they have the same id, then the 1st one is the only one locked.
@@ -1002,6 +1061,7 @@ static int ocfs2_double_lock(struct ocfs2_super *osb,
 			     struct inode *inode2)
 {
 	int status;
+	int inode1_is_ancestor, inode2_is_ancestor;
 	struct ocfs2_inode_info *oi1 = OCFS2_I(inode1);
 	struct ocfs2_inode_info *oi2 = OCFS2_I(inode2);
 	struct buffer_head **tmpbh;
@@ -1015,9 +1075,26 @@ static int ocfs2_double_lock(struct ocfs2_super *osb,
 	if (*bh2)
 		*bh2 = NULL;
 
-	/* we always want to lock the one with the lower lockid first. */
+	/* we always want to lock the one with the lower lockid first.
+	 * and if they are nested, we lock ancestor first */
 	if (oi1->ip_blkno != oi2->ip_blkno) {
-		if (oi1->ip_blkno < oi2->ip_blkno) {
+		inode1_is_ancestor = ocfs2_check_if_ancestor(osb, oi2->ip_blkno,
+				oi1->ip_blkno);
+		if (inode1_is_ancestor < 0) {
+			status = inode1_is_ancestor;
+			goto bail;
+		}
+
+		inode2_is_ancestor = ocfs2_check_if_ancestor(osb, oi1->ip_blkno,
+				oi2->ip_blkno);
+		if (inode2_is_ancestor < 0) {
+			status = inode2_is_ancestor;
+			goto bail;
+		}
+
+		if ((inode1_is_ancestor == 1) ||
+				(oi1->ip_blkno < oi2->ip_blkno &&
+				inode2_is_ancestor == 0)) {
 			/* switch id1 and id2 around */
 			tmpbh = bh2;
 			bh2 = bh1;
@@ -1098,6 +1175,7 @@ static int ocfs2_rename(struct inode *old_dir,
 	struct ocfs2_dir_lookup_result old_entry_lookup = { NULL, };
 	struct ocfs2_dir_lookup_result orphan_insert = { NULL, };
 	struct ocfs2_dir_lookup_result target_insert = { NULL, };
+	bool should_add_orphan = false;
 
 	/* At some point it might be nice to break this function up a
 	 * bit. */
@@ -1134,6 +1212,21 @@ static int ocfs2_rename(struct inode *old_dir,
 			goto bail;
 		}
 		rename_lock = 1;
+
+		/* here we cannot guarantee the inodes haven't just been
+		 * changed, so check if they are nested again */
+		status = ocfs2_check_if_ancestor(osb, new_dir->i_ino,
+				old_inode->i_ino);
+		if (status < 0) {
+			mlog_errno(status);
+			goto bail;
+		} else if (status == 1) {
+			status = -EPERM;
+			trace_ocfs2_rename_not_permitted(
+					(unsigned long long)old_inode->i_ino,
+					(unsigned long long)new_dir->i_ino);
+			goto bail;
+		}
 	}
 
 	/* if old and new are the same, this'll just do one lock. */
@@ -1304,6 +1397,7 @@ static int ocfs2_rename(struct inode *old_dir,
 				mlog_errno(status);
 				goto bail;
 			}
+			should_add_orphan = true;
 		}
 	} else {
 		BUG_ON(new_dentry->d_parent->d_inode != new_dir);
@@ -1348,17 +1442,6 @@ static int ocfs2_rename(struct inode *old_dir,
 			goto bail;
 		}
 
-		if (S_ISDIR(new_inode->i_mode) ||
-		    (ocfs2_read_links_count(newfe) == 1)) {
-			status = ocfs2_orphan_add(osb, handle, new_inode,
-						  newfe_bh, orphan_name,
-						  &orphan_insert, orphan_dir);
-			if (status < 0) {
-				mlog_errno(status);
-				goto bail;
-			}
-		}
-
 		/* change the dirent to point to the correct inode */
 		status = ocfs2_update_entry(new_dir, handle, &target_lookup_res,
 					    old_inode);
@@ -1373,6 +1456,15 @@ static int ocfs2_rename(struct inode *old_dir,
 		else
 			ocfs2_add_links_count(newfe, -1);
 		ocfs2_journal_dirty(handle, newfe_bh);
+		if (should_add_orphan) {
+			status = ocfs2_orphan_add(osb, handle, new_inode,
+					newfe_bh, orphan_name,
+					&orphan_insert, orphan_dir);
+			if (status < 0) {
+				mlog_errno(status);
+				goto bail;
+			}
+		}
 	} else {
 		/* if the name was not found in new_dir, add it now */
 		status = ocfs2_add_entry(handle, new_dentry, old_inode,