aklog: Fix improper use of readlink

readlink doesn't NUL terminate its return string, so it is up to
us to do so.

Caught by coverity (#985739)

Reviewed-on: http://gerrit.openafs.org/9347
Reviewed-by: Derrick Brashear <shadow@your-file-system.com>
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Jeffrey Altman <jaltman@your-file-system.com>
(cherry picked from commit 2fac53522e7ef5b3a376e191bffdc1f6784e6995)

Change-Id: I9d47a6a7cbc86fba3f68f7e47c5d7a0fb924781f
Reviewed-on: http://gerrit.openafs.org/11035
Reviewed-by: Andrew Deason <adeason@sinenomine.net>
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Chas Williams - CONTRACTOR <chas@cmf.nrl.navy.mil>
Reviewed-by: Stephan Wiesand <stephan.wiesand@desy.de>

diff --git a/src/aklog/aklog.c b/src/aklog/aklog.c
index c282c24712c2a53ba4a2d00f0c6e84bb7ea0a018..7d3e7cd93379cc39d0932175d8a36efbdee30199 100644 (file)
--- a/src/aklog/aklog.c
+++ b/src/aklog/aklog.c
@@ -1211,12 +1211,16 @@ next_path(char *origpath)
            ? elast_comp - last_comp : strlen(last_comp);
        strncat(pathtocheck, last_comp, len);
        memset(linkbuf, 0, sizeof(linkbuf));
-       if ((link = (readlink(pathtocheck, linkbuf,
-                                   sizeof(linkbuf)) > 0))) {
+       link = readlink(pathtocheck, linkbuf, sizeof(linkbuf)-1);
+
+       if (link > 0) {
+           linkbuf[link] = '\0'; /* NUL terminate string */
+
            if (++symlinkcount > MAXSYMLINKS) {
                fprintf(stderr, "%s: %s\n", progname, strerror(ELOOP));
                exit(AKLOG_BADPATH);
            }
+
            memset(tmpbuf, 0, sizeof(tmpbuf));
            if (elast_comp)
                strcpy(tmpbuf, elast_comp);