Cleanup VFS mount string handling:

- Avoid using copyinstr() without checking the return value.

- sys_mount() has already copied the path in, so pass this to the
  filesystem mount code so that it does not have to copy it in again.

- Avoid copyinstr()/bzero() dance when we can simply bzero() and strlcpy().

ok krw@

1 files changed, 13 insertions, 9 deletions

diff --git a/sys/ufs/mfs/mfs_vfsops.c b/sys/ufs/mfs/mfs_vfsops.c
index ab362a02ef8..29a941d5b94 100644
--- a/sys/ufs/mfs/mfs_vfsops.c
+++ b/sys/ufs/mfs/mfs_vfsops.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: mfs_vfsops.c,v 1.42 2010/12/21 20:14:44 thib Exp $	*/
+/*	$OpenBSD: mfs_vfsops.c,v 1.43 2012/09/10 11:11:00 jsing Exp $	*/
 /*	$NetBSD: mfs_vfsops.c,v 1.10 1996/02/09 22:31:28 christos Exp $	*/
 
 /*
@@ -91,10 +91,10 @@ mfs_mount(struct mount *mp, const char *path, void *data,
 	struct ufsmount *ump;
 	struct fs *fs;
 	struct mfsnode *mfsp;
-	size_t size;
+	char fspec[MNAMELEN];
 	int flags, error;
 
-	error = copyin(data, (caddr_t)&args, sizeof (struct mfs_args));
+	error = copyin(data, (caddr_t)&args, sizeof(struct mfs_args));
 	if (error)
 		return (error);
 
@@ -116,12 +116,15 @@ mfs_mount(struct mount *mp, const char *path, void *data,
 		if (fs->fs_ronly && (mp->mnt_flag & MNT_WANTRDWR))
 			fs->fs_ronly = 0;
 #ifdef EXPORTMFS
-		if (args.fspec == 0)
+		if (args.fspec == NULL)
 			return (vfs_export(mp, &ump->um_export, 
 			    &args.export_info));
 #endif
 		return (0);
 	}
+	error = copyinstr(args.fspec, fspec, sizeof(fspec), NULL);
+	if (error)
+		return (error);
 	error = getnewvnode(VT_MFS, NULL, &mfs_vops, &devvp);
 	if (error)
 		return (error);
@@ -143,13 +146,14 @@ mfs_mount(struct mount *mp, const char *path, void *data,
 	}
 	ump = VFSTOUFS(mp);
 	fs = ump->um_fs;
-	(void) copyinstr(path, fs->fs_fsmnt, sizeof(fs->fs_fsmnt) - 1, &size);
-	bzero(fs->fs_fsmnt + size, sizeof(fs->fs_fsmnt) - size);
+
+	bzero(fs->fs_fsmnt, sizeof(fs->fs_fsmnt));
+	strlcpy(fs->fs_fsmnt, path, sizeof(fs->fs_fsmnt));
 	bcopy(fs->fs_fsmnt, mp->mnt_stat.f_mntonname, MNAMELEN);
-	(void) copyinstr(args.fspec, mp->mnt_stat.f_mntfromname, MNAMELEN - 1,
-	    &size);
-	bzero(mp->mnt_stat.f_mntfromname + size, MNAMELEN - size);
+	bzero(mp->mnt_stat.f_mntfromname, MNAMELEN);
+	strlcpy(mp->mnt_stat.f_mntfromname, fspec, MNAMELEN);
 	bcopy(&args, &mp->mnt_stat.mount_info.mfs_args, sizeof(args));
+
 	return (0);
 }