bin/151567: [patch] lp(1) fails on ZFS filesystem

[Peter Jeremy]

>Number:         151567
>Category:       bin
>Synopsis:       [patch] lp(1) fails on ZFS filesystem
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Tue Oct 19 01:00:24 UTC 2010
>Closed-Date:
>Last-Modified:
>Originator:     Peter Jeremy
>Release:        FreeBSD 8.1-PRERELEASE amd64
>Organization:
Alcatel-Lucent Australia
>Environment:
System: FreeBSD pjdesk.au.alcatel-lucent.com 8.1-PRERELEASE FreeBSD 8.1-PRERELEASE #19: Wed Jul 14 07:24:18 EST 2010 root at pjdesk.au.alcatel-lucent.com:/var/obj/usr/src/sys/pjdesk amd64

The code is identical in -current.

>Description:
	Printing from a ZFS filesystem using 'lp' fails and returns an
	email reporting "Your printer job was not printed because it was
	not linked to the original file".

	In order to protect against files being switched when files
	are printed using 'lp' or 'lpr -s', the st_dev and st_ino
	values for the original file are saved by lpr and verified
	by lpd before the file is printed.  Unfortunately, lpr prints
	both values using '%d' (although both fields are unsigned)
	and lpd(8) assumes a string of decimal digits.

	ZFS (at least) generates st_dev values greater than 2^31-1,
	resulting in negative values being printed - which lpd cannot
	parse, leading it to report that the file has been switched.

	A similar problem would occur with large inode numbers.

>How-To-Repeat:
	Find a file with either st_dev or st_ino greater than 2^31-1
	(stat(1) will report both numbers) and print it with 'lpq -s'.
	This should generate an email reporting that the file could
	not be printed because it was not linked to the original file

>Fix:
Index: lpr/lpr.c
===================================================================
RCS file: /usr/ncvs/src/usr.sbin/lpr/lpr/lpr.c,v
retrieving revision 1.44.32.1
diff -u -r1.44.32.1 lpr.c
--- lpr/lpr.c	3 Aug 2009 08:13:06 -0000	1.44.32.1
+++ lpr/lpr.c	19 Oct 2010 00:16:00 -0000
@@ -386,7 +386,7 @@
 			continue;	/* file unreasonable */
 
 		if (sflag && (cp = linked(arg)) != NULL) {
-			(void) snprintf(buf, sizeof(buf), "%d %d", statb.st_dev,
+			(void) snprintf(buf, sizeof(buf), "%u %u", statb.st_dev,
 				statb.st_ino);
 			card('S', buf);
 			if (format == 'p')
>Release-Note:
>Audit-Trail:
>Unformatted: