From: "lihuisong (C)" <lihuisong@huawei.com>
To: Tyler Retzlaff <roretzla@linux.microsoft.com>, <dev@dpdk.org>
Cc: Ciara Power <ciara.power@intel.com>, <bruce.richardson@intel.com>,
<lihuisong@huawei.com>
Subject: Re: [PATCH] telemetry: avoid truncation of strlcpy return before check
Date: Tue, 8 Aug 2023 10:24:41 +0800 [thread overview]
Message-ID: <35199239-fac5-f7f2-6f80-5070b016d7d6@huawei.com> (raw)
In-Reply-To: <1691011261-5666-1-git-send-email-roretzla@linux.microsoft.com>
在 2023/8/3 5:21, Tyler Retzlaff 写道:
> strlcpy returns type size_t when directly assigning to
> struct rte_tel_data data_len field it may be truncated leading to
> compromised length check that follows
>
> Since the limit in the check is < UINT_MAX the value returned is
> safe to be cast to unsigned int (which may be narrower than size_t)
> but only after being checked against RTE_TEL_MAX_SINGLE_STRING_LEN
>
> Signed-off-by: Tyler Retzlaff <roretzla@linux.microsoft.com>
> ---
> lib/telemetry/telemetry_data.c | 5 +++--
> 1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/lib/telemetry/telemetry_data.c b/lib/telemetry/telemetry_data.c
> index 3b1a240..52307cb 100644
> --- a/lib/telemetry/telemetry_data.c
> +++ b/lib/telemetry/telemetry_data.c
> @@ -41,12 +41,13 @@
> int
> rte_tel_data_string(struct rte_tel_data *d, const char *str)
> {
> + const size_t len = strlcpy(d->data.str, str, sizeof(d->data.str));
sizeof(d->data.str) is equal to RTE_TEL_MAX_SINGLE_STRING_LEN(8192).
So It seems that this truncation probably will not happen.
> d->type = TEL_STRING;
> - d->data_len = strlcpy(d->data.str, str, sizeof(d->data.str));
> - if (d->data_len >= RTE_TEL_MAX_SINGLE_STRING_LEN) {
> + if (len >= RTE_TEL_MAX_SINGLE_STRING_LEN) {
> d->data_len = RTE_TEL_MAX_SINGLE_STRING_LEN - 1;
> return E2BIG; /* not necessarily and error, just truncation */
> }
> + d->data_len = (unsigned int)len;
> return 0;
> }
>
next prev parent reply other threads:[~2023-08-08 2:24 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-08-02 21:21 Tyler Retzlaff
2023-08-03 8:15 ` Bruce Richardson
2023-08-08 2:24 ` lihuisong (C) [this message]
2023-08-08 17:59 ` Tyler Retzlaff
2023-08-08 18:35 ` Bruce Richardson
2024-02-01 11:45 ` David Marchand
2024-02-01 16:42 ` Tyler Retzlaff
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=35199239-fac5-f7f2-6f80-5070b016d7d6@huawei.com \
--to=lihuisong@huawei.com \
--cc=bruce.richardson@intel.com \
--cc=ciara.power@intel.com \
--cc=dev@dpdk.org \
--cc=roretzla@linux.microsoft.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).