Patch "xfs: don't allow di_size with high bit set" has been added to the 4.4-stable tree

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

xfs: don't allow di_size with high bit set

to the 4.4-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:
xfs-don-t-allow-di_size-with-high-bit-set.patch
and it can be found in the queue-4.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: "Darrick J. Wong" <[email protected]>
Date: Mon, 5 Dec 2016 12:38:38 +1100
Subject: xfs: don't allow di_size with high bit set

From: Darrick J. Wong <[email protected]>

commit ef388e2054feedaeb05399ed654bdb06f385d294 upstream.

The on-disk field di_size is used to set i_size, which is a signed integer of loff_t. If the high bit of di_size is set, we'll end up with a negative i_size, which will cause all sorts of problems. Since the VFS won't let us create a file with such length, we should catch them here in the verifier too.

---
 fs/xfs/libxfs/xfs_inode_buf.c |    8 ++++++++
 1 file changed, 8 insertions(+)

@@ -299,6 +299,14 @@ xfs_dinode_verify(
 	if (dip->di_magic != cpu_to_be16(XFS_DINODE_MAGIC))
 		return false;
 
+	/* don't allow invalid i_size */
+	if (be64_to_cpu(dip->di_size) & (1ULL << 63))
+		return false;
+
+	/* No zero-length symlinks. */
+	if (S_ISLNK(be16_to_cpu(dip->di_mode)) && dip->di_size == 0)
+		return false;
+
 	/* only version 3 or greater inodes are extensively verified here */
 	if (dip->di_version < 3)
 		return true;

Patches currently in stable-queue which might be from [email protected] are

queue-4.4/xfs-don-t-allow-di_size-with-high-bit-set.patch