From: Daniel Lezcano <daniel.lezcano@linaro.org>
To: Dan Carpenter <dan.carpenter@oracle.com>,
Zhang Rui <rui.zhang@intel.com>
Cc: Amit Kucheria <amitk@kernel.org>,
Eduardo Valentin <edubezval@gmail.com>,
linux-pm@vger.kernel.org, kernel-janitors@vger.kernel.org
Subject: Re: [PATCH] thermal/core: Potential buffer overflow in thermal_build_list_of_policies()
Date: Fri, 17 Sep 2021 09:54:50 +0200 [thread overview]
Message-ID: <819b1be3-851a-e5ac-95f4-53a94a5dd457@linaro.org> (raw)
In-Reply-To: <20210916131342.GB25094@kili>
On 16/09/2021 15:13, Dan Carpenter wrote:
> After printing the list of thermal governors, then this function prints
> a newline character. The problem is that "size" has not been updated
> after printing the last governor. This means that it can write one
> character (the NUL terminator) beyond the end of the buffer.
>
> Get rid of the "size" variable and just use "PAGE_SIZE - count" directly.
>
> Fixes: 1b4f48494eb2 ("thermal: core: group functions related to governor handling")
> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
> ---
Applied, thanks
> drivers/thermal/thermal_core.c | 7 +++----
> 1 file changed, 3 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.c
> index 97ef9b040b84..51374f4e1cca 100644
> --- a/drivers/thermal/thermal_core.c
> +++ b/drivers/thermal/thermal_core.c
> @@ -222,15 +222,14 @@ int thermal_build_list_of_policies(char *buf)
> {
> struct thermal_governor *pos;
> ssize_t count = 0;
> - ssize_t size = PAGE_SIZE;
>
> mutex_lock(&thermal_governor_lock);
>
> list_for_each_entry(pos, &thermal_governor_list, governor_list) {
> - size = PAGE_SIZE - count;
> - count += scnprintf(buf + count, size, "%s ", pos->name);
> + count += scnprintf(buf + count, PAGE_SIZE - count, "%s ",
> + pos->name);
> }
> - count += scnprintf(buf + count, size, "\n");
> + count += scnprintf(buf + count, PAGE_SIZE - count, "\n");
>
> mutex_unlock(&thermal_governor_lock);
>
>
--
<http://www.linaro.org/> Linaro.org │ Open source software for ARM SoCs
Follow Linaro: <http://www.facebook.com/pages/Linaro> Facebook |
<http://twitter.com/#!/linaroorg> Twitter |
<http://www.linaro.org/linaro-blog/> Blog
prev parent reply other threads:[~2021-09-17 7:54 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-09-16 13:13 [PATCH] thermal/core: Potential buffer overflow in thermal_build_list_of_policies() Dan Carpenter
2021-09-17 7:54 ` Daniel Lezcano [this message]
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=819b1be3-851a-e5ac-95f4-53a94a5dd457@linaro.org \
--to=daniel.lezcano@linaro.org \
--cc=amitk@kernel.org \
--cc=dan.carpenter@oracle.com \
--cc=edubezval@gmail.com \
--cc=kernel-janitors@vger.kernel.org \
--cc=linux-pm@vger.kernel.org \
--cc=rui.zhang@intel.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).