From: kn <kn@openbsd.org>
Date: Wed, 11 Jul 2018 17:44:57 +0000 (+0000)
Subject: Prevent updating async option on softdep mount
X-Git-Url: http://artulab.com/gitweb/?a=commitdiff_plain;h=d06c8448c5885a451f2f0ce33fc96eaf52ec1979;p=openbsd

Prevent updating async option on softdep mount

`mount -uo async,nosoftdep /mnt' would set "async" but keep "softdep"
untouched on a read/write mount.

OK deraadt krw beck bluhm
---

diff --git a/sys/ufs/ffs/ffs_vfsops.c b/sys/ufs/ffs/ffs_vfsops.c
index 0695d54a489..6c52beaa6f8 100644
--- a/sys/ufs/ffs/ffs_vfsops.c
+++ b/sys/ufs/ffs/ffs_vfsops.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ffs_vfsops.c,v 1.177 2018/05/27 06:02:15 visa Exp $	*/
+/*	$OpenBSD: ffs_vfsops.c,v 1.178 2018/07/11 17:44:57 kn Exp $	*/
 /*	$NetBSD: ffs_vfsops.c,v 1.19 1996/02/09 22:22:26 christos Exp $	*/
 
 /*
@@ -241,6 +241,16 @@ ffs_mount(struct mount *mp, const char *path, void *data,
 		error = 0;
 		ronly = fs->fs_ronly;
 
+		/*
+		 * Soft updates won't be set if read/write,
+		 * so "async" will be illegal.
+		 */
+		if (ronly == 0 && (mp->mnt_flag & MNT_ASYNC) &&
+		    (fs->fs_flags & FS_DOSOFTDEP)) {
+			error = EINVAL;
+			goto error_1;
+		}
+
 		if (ronly == 0 && (mp->mnt_flag & MNT_RDONLY)) {
 			/* Flush any dirty data */
 			VFS_SYNC(mp, MNT_WAIT, 0, p->p_ucred, p);