Return-Path: Received: from mx1.redhat.com ([209.132.183.28]:55900 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965397AbbKDVyU (ORCPT ); Wed, 4 Nov 2015 16:54:20 -0500 Received: from int-mx14.intmail.prod.int.phx2.redhat.com (int-mx14.intmail.prod.int.phx2.redhat.com [10.5.11.27]) by mx1.redhat.com (Postfix) with ESMTPS id 4BD2815447 for ; Wed, 4 Nov 2015 21:54:20 +0000 (UTC) Subject: Re: [PATCH] exportfs: Fix buf size in test_export() dump(). To: "stevens.yin" , linux-nfs@vger.kernel.org References: <1446608590-3556-1-git-send-email-jiyin@redhat.com> From: Steve Dickson Message-ID: <563A7E8B.4060805@RedHat.com> Date: Wed, 4 Nov 2015 16:54:19 -0500 MIME-Version: 1.0 In-Reply-To: <1446608590-3556-1-git-send-email-jiyin@redhat.com> Content-Type: text/plain; charset=windows-1252 Sender: linux-nfs-owner@vger.kernel.org List-ID: On 11/03/2015 10:43 PM, stevens.yin wrote: > From: Jianhong Yin > > The buf[] size in test_export() is not enough for NFS_MAXPATHLEN > + prefix/suffix proto string. Fix it and same issue in dump(). > And just to be on the safe side, %s/sprintf/snprintf/ Next time please add a proper Signed-off-by line. Since I do know the history of this patch I did the Signed-off-by. Committed... steved. > --- > utils/exportfs/exportfs.c | 13 ++++++++----- > 1 file changed, 8 insertions(+), 5 deletions(-) > > diff --git a/utils/exportfs/exportfs.c b/utils/exportfs/exportfs.c > index 8758231..c7a79a6 100644 > --- a/utils/exportfs/exportfs.c > +++ b/utils/exportfs/exportfs.c > @@ -499,9 +499,10 @@ unexportfs(char *arg, int verbose) > > static int can_test(void) > { > - char buf[1024]; > + char buf[1024] = { 0 }; > int fd; > int n; > + size_t bufsiz = sizeof(buf); > > fd = open("/proc/net/rpc/auth.unix.ip/channel", O_WRONLY); > if (fd < 0) > @@ -514,9 +515,9 @@ static int can_test(void) > * commit 2f74f972 (sunrpc: prepare NFS for 2038). > */ > if (time(NULL) > INT_TO_LONG_THRESHOLD_SECS) > - sprintf(buf, "nfsd 0.0.0.0 %ld -test-client-\n", LONG_MAX); > + snprintf(buf, bufsiz-1, "nfsd 0.0.0.0 %ld -test-client-\n", LONG_MAX); > else > - sprintf(buf, "nfsd 0.0.0.0 %d -test-client-\n", INT_MAX); > + snprintf(buf, bufsiz-1, "nfsd 0.0.0.0 %d -test-client-\n", INT_MAX); > > n = write(fd, buf, strlen(buf)); > close(fd); > @@ -532,7 +533,8 @@ static int can_test(void) > > static int test_export(char *path, int with_fsid) > { > - char buf[1024]; > + /* beside max path, buf size should take protocol str into account */ > + char buf[NFS_MAXPATHLEN+1+64] = { 0 }; > char *bp = buf; > int len = sizeof(buf); > int fd, n; > @@ -758,7 +760,8 @@ dumpopt(char c, char *fmt, ...) > static void > dump(int verbose, int export_format) > { > - char buf[1024]; > + /* buf[] size should >= sizeof(struct exportent->e_path) */ > + char buf[NFS_MAXPATHLEN+1] = { 0 }; > char *bp; > int len; > nfs_export *exp; >