Date: Sat, 4 May 2013 21:54:20 +0300 From: Mikolaj Golub <trociny@FreeBSD.org> To: John Baldwin <jhb@FreeBSD.org> Cc: svn-src-head@freebsd.org, svn-src-all@freebsd.org, src-committers@freebsd.org Subject: Re: svn commit: r250223 - in head: lib/libprocstat sys/kern sys/sys usr.bin/fstat Message-ID: <20130504185419.GA32075@gmail.com> In-Reply-To: <201305032111.r43LBvZ3040508@svn.freebsd.org> References: <201305032111.r43LBvZ3040508@svn.freebsd.org>
next in thread | previous in thread | raw e-mail | index | archive | help
On Fri, May 03, 2013 at 09:11:57PM +0000, John Baldwin wrote:
> +static int
> +procstat_get_sem_info_kvm(kvm_t *kd, struct filestat *fst,
> + struct semstat *sem, char *errbuf)
> +{
> + struct ksem ksem;
> + void *ksemp;
> + char *path;
> + int i;
> +
> + assert(kd);
> + assert(sem);
> + assert(fst);
> + bzero(sem, sizeof(*sem));
> + ksemp = fst->fs_typedep;
> + if (ksemp == NULL)
> + goto fail;
> + if (!kvm_read_all(kd, (unsigned long)ksemp, &ksem,
> + sizeof(struct ksem))) {
> + warnx("can't read ksem at %p", (void *)ksemp);
> + goto fail;
> + }
> + sem->mode = S_IFREG | ksem.ks_mode;
> + sem->value = ksem.ks_value;
> + if (fst->fs_path == NULL && ksem.ks_path != NULL) {
> + path = malloc(MAXPATHLEN);
> + for (i = 0; i < MAXPATHLEN - 1; i++) {
> + if (!kvm_read_all(kd, (unsigned long)ksem.ks_path + i,
> + path + i, 1))
> + break;
> + if (path[i] == '\0')
> + break;
> + }
> + path[i] = '\0';
> + if (i == 0)
> + free(path);
> + else
> + fst->fs_path = path;
> + }
> + return (0);
> +
> +fail:
> + snprintf(errbuf, _POSIX2_LINE_MAX, "error");
> + return (1);
> +}
I would like to make errbuf optional (for all libprocstat functions
that provide it) adding a check before printing to errbuf:
if (errbuf != NULL)
snprintf(errbuf, ...
It looks like there are callers who are not interested in errbuf
content. E.g. currently procstat(1) passes NULL when calling functions
that require errbuf, namely procstat_get_socket_info and
procstat_get_vnode_info, potentially crashing here if an error occurs.
Do you (anyone) have objections?
--
Mikolaj Golub
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20130504185419.GA32075>