bin/186152: [patch] freebsd-update -b: correctly handle symlinks with absolute paths

[David Shane Holden]

>Number:         186152
>Category:       bin
>Synopsis:       [patch] freebsd-update -b: correctly handle symlinks with absolute paths
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Mon Jan 27 01:50:00 UTC 2014
>Closed-Date:
>Last-Modified:
>Originator:     David Shane Holden
>Release:        10.0-RELEASE
>Organization:
>Environment:
FreeBSD node 10.0-RELEASE FreeBSD 10.0-RELEASE #0 r260789: Thu Jan 16 22:34:59 UTC 2014     root at snap.freebsd.org:/usr/obj/usr/src/sys/GENERIC  amd64
>Description:
When upgrading a base directory (freebsd-update -b), symlinks with absolute paths are checked against the host system instead of the base directory which was causing the problem reported at https://forums.freebsd.org/viewtopic.php?f=5&t=44520.

>How-To-Repeat:
Check forums thread.
>Fix:


Patch attached with submission follows:

--- freebsd-update.orig	2014-01-27 01:03:59.000000000 +0000
+++ freebsd-update	2014-01-27 01:18:01.000000000 +0000
@@ -1437,11 +1437,21 @@
 	# sorted by device and inode number.
 	while read F; do
 		# If the symlink/file/directory does not exist, record this.
-		if ! [ -e ${BASEDIR}/${F} ]; then
+		# Symlinks with absolute paths need to be checked relative
+		# to their base directories.
+		FF=${F}
+		if [ -L ${BASEDIR}/${F} ]; then
+			LINK=`readlink ${BASEDIR}/${F}`
+			echo "${LINK}" | grep -qe "^/"
+			if [ $? -eq 0 ]; then
+				FF=${LINK}
+			fi
+		fi
+		if ! [ -e ${BASEDIR}/${FF} ]; then
 			echo "${F}|-||||||"
 			continue
 		fi
-		if ! [ -r ${BASEDIR}/${F} ]; then
+		if ! [ -r ${BASEDIR}/${FF} ]; then
 			echo "Cannot read file: ${BASEDIR}/${F}"	\
 			    >/dev/stderr
 			touch .err


>Release-Note:
>Audit-Trail:
>Unformatted: