bin/123021: mount(8): mount -p shows incorrect mount options [regression]

[Jaakko Heinonen]

The following reply was made to PR bin/123021; it has been noted by GNATS.

From: Jaakko Heinonen <jh at saunalahti.fi>
To: bug-followup at FreeBSD.org, citrin at citrin.ru
Cc:  
Subject: Re: bin/123021: mount(8): mount -p shows incorrect mount options
	[regression]
Date: Thu, 22 May 2008 22:41:57 +0300

 The bug was introduced in mount.c revision 1.82. There was an attempt to
 fix the bug in revision 1.83 but the fix is incomplete.
 
 I first thought this patch but it might break something since
 flags2opts() was changed in r1.82 specifically not to return "rw".
 
 Index: mount.c
 ===================================================================
 RCS file: /home/ncvs/src/sbin/mount/mount.c,v
 retrieving revision 1.98
 diff -p -u -r1.98 mount.c
 --- mount.c	4 Feb 2008 07:37:56 -0000	1.98
 +++ mount.c	14 May 2008 15:12:13 -0000
 @@ -819,10 +819,6 @@ putfsent(struct statfs *ent)
  		    +1));
  	}
  
 -	/*
 -	 * "rw" is not a real mount option; this is why we print NULL as "rw"
 -	 * if opts is still NULL here.
 -	 */
  	l = strlen(ent->f_mntfromname);
  	printf("%s%s%s%s", ent->f_mntfromname,
  	    l < 8 ? "\t" : "",
 @@ -834,13 +830,9 @@ putfsent(struct statfs *ent)
  	    l < 16 ? "\t" : "",
  	    l < 24 ? "\t" : " ");
  	printf("%s\t", ent->f_fstypename);
 -	if (opts == NULL) {
 -		printf("%s\t", "rw");
 -	} else {
 -		l = strlen(opts);
 -		printf("%s%s", opts,
 -		    l < 8 ? "\t" : " ");
 -	}
 +	l = strlen(opts);
 +	printf("%s%s", opts,
 +	    l < 8 ? "\t" : " ");
  	free(opts);
  
  	if ((fst = getfsspec(ent->f_mntfromname)))
 @@ -864,7 +856,10 @@ flags2opts(int flags)
  
  	res = NULL;
  
 -	if (flags & MNT_RDONLY)		res = catopt(res, "ro");
 +	if (flags & MNT_RDONLY)
 +		res = catopt(res, "ro");
 +	else
 +		res = catopt(res, "rw");
  	if (flags & MNT_SYNCHRONOUS)	res = catopt(res, "sync");
  	if (flags & MNT_NOEXEC)		res = catopt(res, "noexec");
  	if (flags & MNT_NOSUID)		res = catopt(res, "nosuid");
 
 
 This patch possibly avoids breaking things but it feels more hacky:
 
 Index: mount.c
 ===================================================================
 RCS file: /home/ncvs/src/sbin/mount/mount.c,v
 retrieving revision 1.98
 diff -p -u -r1.98 mount.c
 --- mount.c	4 Feb 2008 07:37:56 -0000	1.98
 +++ mount.c	22 May 2008 19:02:12 -0000
 @@ -838,6 +838,10 @@ putfsent(struct statfs *ent)
  		printf("%s\t", "rw");
  	} else {
  		l = strlen(opts);
 +		if (!(ent->f_flags & MNT_RDONLY))  {
 +			printf("rw,");
 +			l += 3;
 +		}
  		printf("%s%s", opts,
  		    l < 8 ? "\t" : " ");
  	}