Date: Mon, 26 Nov 2012 03:58:28 GMT From: Garrett Cooper <yanegomi@gmail.com> To: freebsd-gnats-submit@FreeBSD.org Subject: bin/173923: [patch] save errno before calling fprintf in cpucontrol(8) error paths Message-ID: <201211260358.qAQ3wSCp033956@red.freebsd.org> Resent-Message-ID: <201211260400.qAQ40018092344@freefall.freebsd.org>
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>Number: 173923
>Category: bin
>Synopsis: [patch] save errno before calling fprintf in cpucontrol(8) error 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 Nov 26 04:00:00 UTC 2012
>Closed-Date:
>Last-Modified:
>Originator: Garrett Cooper
>Release: 9-STABLE
>Organization:
EMC Isilon
>Environment:
FreeBSD bayonetta.local 9.1-PRERELEASE FreeBSD 9.1-PRERELEASE #0 r240836M: Sat Sep 22 12:30:11 PDT 2012 gcooper@bayonetta.local:/usr/obj/store/freebsd/stable/9/sys/BAYONETTA amd64
>Description:
fprintf can mangle errno, tainting WARN calls. The attached patch saves errno in error (which was used to store the return code from the ioctl(2) calls) and restores it after calling WARN.
>How-To-Repeat:
>Fix:
Patch attached with submission follows:
Index: usr.sbin/cpucontrol/intel.c
===================================================================
--- usr.sbin/cpucontrol/intel.c (revision 242874)
+++ usr.sbin/cpucontrol/intel.c (working copy)
@@ -33,6 +33,7 @@
#include <unistd.h>
#include <fcntl.h>
#include <err.h>
+#include <errno.h>
#include <sys/types.h>
#include <sys/stat.h>
@@ -266,7 +267,9 @@
args.size = data_size;
error = ioctl(devfd, CPUCTL_UPDATE, &args);
if (error < 0) {
+ error = errno;
fprintf(stderr, "failed.\n");
+ errno = error;
WARN(0, "ioctl()");
goto fail;
}
Index: usr.sbin/cpucontrol/via.c
===================================================================
--- usr.sbin/cpucontrol/via.c (revision 242874)
+++ usr.sbin/cpucontrol/via.c (working copy)
@@ -33,6 +33,7 @@
#include <unistd.h>
#include <fcntl.h>
#include <err.h>
+#include <errno.h>
#include <sys/types.h>
#include <sys/stat.h>
@@ -204,7 +205,9 @@
args.size = data_size;
error = ioctl(devfd, CPUCTL_UPDATE, &args);
if (error < 0) {
+ error = errno;
fprintf(stderr, "failed.\n");
+ errno = error;
WARN(0, "ioctl()");
goto fail;
}
>Release-Note:
>Audit-Trail:
>Unformatted:
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