From: Pablo Neira Ayuso <pablo@netfilter.org>
To: Eric Leblond <eric@inl.fr>
Cc: netfilter-devel@vger.kernel.org
Subject: Re: [PATCH 6/6] ulogd: use snprintf instead of sprintf in printpkt
Date: Thu, 30 Sep 2010 11:48:50 +0200 [thread overview]
Message-ID: <4CA45D02.8040702@netfilter.org> (raw)
In-Reply-To: <1285116442-32490-7-git-send-email-eric@inl.fr>
Hi Eric,
On 22/09/10 02:47, Eric Leblond wrote:
> diff --git a/util/printpkt.c b/util/printpkt.c
> index 5250792..a800555 100644
> --- a/util/printpkt.c
> +++ b/util/printpkt.c
> @@ -106,91 +106,93 @@ struct ulogd_key printpkt_keys[] = {
> [KEY_SCTP_DPORT] = { .name = "sctp.dport", },
> };
>
> -static int printpkt_proto(struct ulogd_key *res, char *buf, int protocol)
> +static int printpkt_proto(struct ulogd_key *res, char *buf, size_t bufsiz, int protocol)
> {
> char *buf_cur = buf;
> + char *end_buf = buf + bufsiz;
> +
>
> switch (protocol) {
> case IPPROTO_TCP:
> - buf_cur += sprintf(buf_cur, "PROTO=TCP ");
> + buf_cur += snprintf(buf_cur, bufsiz, "PROTO=TCP ");
If you have to fix this. snprintf can return -1 in case of error.
Moreover, it returns the number of bytes that would have been written if
there's space in the buffer. So you have to check if the return value is
higher that the remaining space in the buffer.
Have a look at the use of snprintf in libnetfilter_queue and
libnetfilter_log in nf*snprintf_xml() function for instance.
prev parent reply other threads:[~2010-09-30 9:48 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-09-22 0:47 [ULOGD PATCH 0/6] misc improvements and code cleaning Eric Leblond
2010-09-22 0:47 ` [PATCH 1/6] build: nfct and nflog can be disabled via configure option Eric Leblond
2010-09-30 9:58 ` Pablo Neira Ayuso
2010-09-22 0:47 ` [PATCH 2/6] ulogd.conf: Comment library dependant plugins Eric Leblond
2010-09-30 9:51 ` Pablo Neira Ayuso
2010-09-30 21:23 ` Eric Leblond
2010-09-22 0:47 ` [PATCH 3/6] build: add debug configure flag Eric Leblond
2010-09-30 9:50 ` Pablo Neira Ayuso
2010-09-30 21:22 ` Eric Leblond
2010-10-01 22:22 ` Jan Engelhardt
2010-10-03 10:15 ` Pablo Neira Ayuso
2010-09-22 0:47 ` [PATCH 4/6] ulogd.conf: add a complex but useful stack example Eric Leblond
2010-09-22 0:47 ` [PATCH 5/6] filter_MARK: code factorization Eric Leblond
2010-09-22 0:47 ` [PATCH 6/6] ulogd: use snprintf instead of sprintf in printpkt Eric Leblond
2010-09-30 9:48 ` Pablo Neira Ayuso [this message]
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