Patch "NFSv4.1/pNFS: Fix borken function _same_data_server_addrs_locked()" has been added to the 4.2-stable tree

[<gregkh@linuxfoundation.org>]

This is a note to let you know that I've just added the patch titled

    NFSv4.1/pNFS: Fix borken function _same_data_server_addrs_locked()

to the 4.2-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     nfsv4.1-pnfs-fix-borken-function-_same_data_server_addrs_locked.patch
and it can be found in the queue-4.2 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From 6f536936b79bd4b5cea8fb0e5b8b0bce8cd1ea4a Mon Sep 17 00:00:00 2001
From: Trond Myklebust <trond.myklebust@primarydata.com>
Date: Thu, 13 Aug 2015 10:59:07 -0400
Subject: NFSv4.1/pNFS: Fix borken function _same_data_server_addrs_locked()

From: Trond Myklebust <trond.myklebust@primarydata.com>

commit 6f536936b79bd4b5cea8fb0e5b8b0bce8cd1ea4a upstream.

- Switch back to using list_for_each_entry(). Fixes an incorrect test
  for list NULL termination.
- Do not assume that lists are sorted.
- Finally, consider an existing entry to match if it consists of a subset
  of the addresses in the new entry.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 fs/nfs/pnfs_nfs.c |   31 ++++++++++++++++++-------------
 1 file changed, 18 insertions(+), 13 deletions(-)

--- a/fs/nfs/pnfs_nfs.c
+++ b/fs/nfs/pnfs_nfs.c
@@ -359,26 +359,31 @@ same_sockaddr(struct sockaddr *addr1, st
 	return false;
 }
 
+/*
+ * Checks if 'dsaddrs1' contains a subset of 'dsaddrs2'. If it does,
+ * declare a match.
+ */
 static bool
 _same_data_server_addrs_locked(const struct list_head *dsaddrs1,
 			       const struct list_head *dsaddrs2)
 {
 	struct nfs4_pnfs_ds_addr *da1, *da2;
+	struct sockaddr *sa1, *sa2;
+	bool match = false;
 
-	/* step through both lists, comparing as we go */
-	for (da1 = list_first_entry(dsaddrs1, typeof(*da1), da_node),
-	     da2 = list_first_entry(dsaddrs2, typeof(*da2), da_node);
-	     da1 != NULL && da2 != NULL;
-	     da1 = list_entry(da1->da_node.next, typeof(*da1), da_node),
-	     da2 = list_entry(da2->da_node.next, typeof(*da2), da_node)) {
-		if (!same_sockaddr((struct sockaddr *)&da1->da_addr,
-				   (struct sockaddr *)&da2->da_addr))
-			return false;
+	list_for_each_entry(da1, dsaddrs1, da_node) {
+		sa1 = (struct sockaddr *)&da1->da_addr;
+		match = false;
+		list_for_each_entry(da2, dsaddrs2, da_node) {
+			sa2 = (struct sockaddr *)&da2->da_addr;
+			match = same_sockaddr(sa1, sa2);
+			if (match)
+				break;
+		}
+		if (!match)
+			break;
 	}
-	if (da1 == NULL && da2 == NULL)
-		return true;
-
-	return false;
+	return match;
 }
 
 /*


Patches currently in stable-queue which might be from trond.myklebust@primarydata.com are

queue-4.2/nfs-don-t-let-the-ctime-override-attribute-barriers.patch
queue-4.2/nfsv4-don-t-set-setattr-for-o_rdonly-o_excl.patch
queue-4.2/nfsv4.1-pnfs-fix-borken-function-_same_data_server_addrs_locked.patch
queue-4.2/nfsv4.1-pnfs-fix-atomicity-of-commit-list-updates.patch