Merge tag 'xfs-4.17-fixes-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux

Pull xfs fixes from Darrick Wong:
"Here are a few more bug fixes for xfs for 4.17-rc4. Most of them are
fixes for bad behavior.

This series has been run through a full xfstests run during LSF and
through a quick xfstests run against this morning's master, with no
major failures reported.

Summary:

- Enhance inode fork verifiers to prevent loading of corrupted
metadata.

- Fix a crash when we try to convert extents format inodes to btree
format, we run out of space, but forget to revert the in-core state
changes.

- Fix file size checks when doing INSERT_RANGE that could cause files
to end up negative size if there previously was an extent mapped at
s_maxbytes.

- Fix a bug when doing a remove-then-add ATTR_REPLACE xattr update
where we forget to clear ATTR_REPLACE after the remove, which
causes the attr to be lost and the fs to shut down due to (what it
thinks is) inconsistent in-core state"

* tag 'xfs-4.17-fixes-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
xfs: don't fail when converting shortform attr to long form during ATTR_REPLACE
xfs: prevent creating negative-sized file via INSERT_RANGE
xfs: set format back to extents if xfs_bmap_extents_to_btree
xfs: enhance dinode verifier

fs/xfs/libxfs/xfs_attr.c

···
 		if (args->flags & ATTR_CREATE)
 			return retval;
 		retval = xfs_attr_shortform_remove(args);
-		ASSERT(retval == 0);
+		if (retval)
+			return retval;
+		/*
+		 * Since we have removed the old attr, clear ATTR_REPLACE so
+		 * that the leaf format add routine won't trip over the attr
+		 * not being around.
+		 */
+		args->flags &= ~ATTR_REPLACE;
 	}
 
 	if (args->namelen >= XFS_ATTR_SF_ENTSIZE_MAX ||

fs/xfs/libxfs/xfs_bmap.c

···
 	*logflagsp = 0;
 	if ((error = xfs_alloc_vextent(&args))) {
 		xfs_iroot_realloc(ip, -1, whichfork);
+		ASSERT(ifp->if_broot == NULL);
+		XFS_IFORK_FMT_SET(ip, whichfork, XFS_DINODE_FMT_EXTENTS);
 		xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
 		return error;
 	}
 
 	if (WARN_ON_ONCE(args.fsbno == NULLFSBLOCK)) {
 		xfs_iroot_realloc(ip, -1, whichfork);
+		ASSERT(ifp->if_broot == NULL);
+		XFS_IFORK_FMT_SET(ip, whichfork, XFS_DINODE_FMT_EXTENTS);
 		xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
 		return -ENOSPC;
 	}

fs/xfs/libxfs/xfs_inode_buf.c

···
 				return __this_address;
 			if (di_size > XFS_DFORK_DSIZE(dip, mp))
 				return __this_address;
+			if (dip->di_nextents)
+				return __this_address;
 			/* fall through */
 		case XFS_DINODE_FMT_EXTENTS:
 		case XFS_DINODE_FMT_BTREE:
···
 	if (XFS_DFORK_Q(dip)) {
 		switch (dip->di_aformat) {
 		case XFS_DINODE_FMT_LOCAL:
+			if (dip->di_anextents)
+				return __this_address;
+		/* fall through */
 		case XFS_DINODE_FMT_EXTENTS:
 		case XFS_DINODE_FMT_BTREE:
 			break;
 		default:
 			return __this_address;
 		}
+	} else {
+		/*
+		 * If there is no fork offset, this may be a freshly-made inode
+		 * in a new disk cluster, in which case di_aformat is zeroed.
+		 * Otherwise, such an inode must be in EXTENTS format; this goes
+		 * for freed inodes as well.
+		 */
+		switch (dip->di_aformat) {
+		case 0:
+		case XFS_DINODE_FMT_EXTENTS:
+			break;
+		default:
+			return __this_address;
+		}
+		if (dip->di_anextents)
+			return __this_address;
 	}
 
 	/* only version 3 or greater inodes are extensively verified here */

fs/xfs/xfs_file.c

···
 		if (error)
 			goto out_unlock;
 	} else if (mode & FALLOC_FL_INSERT_RANGE) {
-		unsigned int blksize_mask = i_blocksize(inode) - 1;
+		unsigned int	blksize_mask = i_blocksize(inode) - 1;
+		loff_t		isize = i_size_read(inode);
 
-		new_size = i_size_read(inode) + len;
 		if (offset & blksize_mask || len & blksize_mask) {
 			error = -EINVAL;
 			goto out_unlock;
 		}
 
-		/* check the new inode size does not wrap through zero */
-		if (new_size > inode->i_sb->s_maxbytes) {
+		/*
+		 * New inode size must not exceed ->s_maxbytes, accounting for
+		 * possible signed overflow.
+		 */
+		if (inode->i_sb->s_maxbytes - isize < len) {
 			error = -EFBIG;
 			goto out_unlock;
 		}
+		new_size = isize + len;
 
 		/* Offset should be less than i_size */
-		if (offset >= i_size_read(inode)) {
+		if (offset >= isize) {
 			error = -EINVAL;
 			goto out_unlock;
 		}