jfs: Don't clear SGID when inheriting ACLs

commit 9bcf66c7 upstream.

When new directory 'DIR1' is created in a directory 'DIR0' with SGID bit
set, DIR1 is expected to have SGID bit set (and owning group equal to
the owning group of 'DIR0'). However when 'DIR0' also has some default
ACLs that 'DIR1' inherits, setting these ACLs will result in SGID bit on
'DIR1' to get cleared if user is not member of the owning group.

Fix the problem by moving posix_acl_update_mode() out of
__jfs_set_acl() into jfs_set_acl(). That way the function will not be
called when inheriting ACLs which is what we want as it prevents SGID
bit clearing and the mode has been properly set by posix_acl_create()
anyway.

Fixes: 07393101
CC: jfs-discussion@lists.sourceforge.net
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

fs/jfs/acl.c

@@ -77,13 +77,6 @@ static int __jfs_set_acl(tid_t tid, struct inode *inode, int type,
 	switch (type) {
 	case ACL_TYPE_ACCESS:
 		ea_name = XATTR_NAME_POSIX_ACL_ACCESS;
-		if (acl) {
-			rc = posix_acl_update_mode(inode, &inode->i_mode, &acl);
-			if (rc)
-				return rc;
-			inode->i_ctime = current_time(inode);
-			mark_inode_dirty(inode);
-		}
 		break;
 	case ACL_TYPE_DEFAULT:
 		ea_name = XATTR_NAME_POSIX_ACL_DEFAULT;
@@ -118,9 +111,17 @@ int jfs_set_acl(struct inode *inode, struct posix_acl *acl, int type)
 
 	tid = txBegin(inode->i_sb, 0);
 	mutex_lock(&JFS_IP(inode)->commit_mutex);
+	if (type == ACL_TYPE_ACCESS && acl) {
+		rc = posix_acl_update_mode(inode, &inode->i_mode, &acl);
+		if (rc)
+			goto end_tx;
+		inode->i_ctime = current_time(inode);
+		mark_inode_dirty(inode);
+	}
 	rc = __jfs_set_acl(tid, inode, type, acl);
 	if (!rc)
 		rc = txCommit(tid, 1, &inode, 0);
+end_tx:
 	txEnd(tid);
 	mutex_unlock(&JFS_IP(inode)->commit_mutex);
 	return rc;