From: Jarkko Sakkinen <jarkko@kernel.org>
To: "Mickaël Salaün" <mic@digikod.net>
Cc: "David Howells" <dhowells@redhat.com>,
"David Woodhouse" <dwmw2@infradead.org>,
"David S . Miller" <davem@davemloft.net>,
"Herbert Xu" <herbert@gondor.apana.org.au>,
"James Morris" <jmorris@namei.org>,
"Mickaël Salaün" <mic@linux.microsoft.com>,
"Mimi Zohar" <zohar@linux.ibm.com>,
"Serge E . Hallyn" <serge@hallyn.com>,
keyrings@vger.kernel.org, linux-crypto@vger.kernel.org,
linux-integrity@vger.kernel.org, linux-kernel@vger.kernel.org,
linux-security-module@vger.kernel.org,
"Ben Boeckel" <mathstuf@gmail.com>
Subject: Re: [PATCH v3 02/10] certs: Fix blacklisted hexadecimal hash string check
Date: Wed, 20 Jan 2021 05:43:52 +0200 [thread overview]
Message-ID: <YAem+DjBR92WG+bK@kernel.org> (raw)
In-Reply-To: <20210114151909.2344974-3-mic@digikod.net>
On Thu, Jan 14, 2021 at 04:19:01PM +0100, Mickaël Salaün wrote:
> From: Mickaël Salaün <mic@linux.microsoft.com>
>
> When looking for a blacklisted hash, bin2hex() is used to transform a
> binary hash to an ascii (lowercase) hexadecimal string. This string is
> then search for in the description of the keys from the blacklist
> keyring. When adding a key to the blacklist keyring,
> blacklist_vet_description() checks the hash prefix and the hexadecimal
> string, but not that this string is lowercase. It is then valid to set
> hashes with uppercase hexadecimal, which will be silently ignored by the
> kernel.
>
> Add an additional check to blacklist_vet_description() to check that
> hexadecimal strings are in lowercase.
>
> Cc: David Woodhouse <dwmw2@infradead.org>
> Signed-off-by: Mickaël Salaün <mic@linux.microsoft.com>
> Signed-off-by: David Howells <dhowells@redhat.com>
> Reviewed-by: Ben Boeckel <mathstuf@gmail.com>
> ---
>
> Changes since v2:
> * Cherry-pick v1 patch from
> https://lore.kernel.org/lkml/2659836.1607940186@warthog.procyon.org.uk/
> to rebase on v5.11-rc3.
> * Rearrange Cc order.
> ---
> certs/blacklist.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/certs/blacklist.c b/certs/blacklist.c
> index 2719fb2fbc1c..a888b934a1cd 100644
> --- a/certs/blacklist.c
> +++ b/certs/blacklist.c
> @@ -37,7 +37,7 @@ static int blacklist_vet_description(const char *desc)
> found_colon:
> desc++;
> for (; *desc; desc++) {
> - if (!isxdigit(*desc))
> + if (!isxdigit(*desc) || isupper(*desc))
> return -EINVAL;
> n++;
> }
> --
> 2.30.0
>
Shouldn't this rather convert the upper case to lower case? I don't like
the ABI break that this causes.
/Jarkko
next prev parent reply other threads:[~2021-01-20 3:47 UTC|newest]
Thread overview: 33+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-01-14 15:18 [PATCH v3 00/10] Enable root to update the blacklist keyring Mickaël Salaün
2021-01-14 15:19 ` [PATCH v3 01/10] certs/blacklist: fix kernel doc interface issue Mickaël Salaün
2021-01-20 3:39 ` Jarkko Sakkinen
2021-01-14 15:19 ` [PATCH v3 02/10] certs: Fix blacklisted hexadecimal hash string check Mickaël Salaün
2021-01-20 3:43 ` Jarkko Sakkinen [this message]
2021-01-20 11:12 ` Mickaël Salaün
2021-01-20 23:44 ` Jarkko Sakkinen
2021-01-14 15:19 ` [PATCH v3 03/10] PKCS#7: Fix missing include Mickaël Salaün
2021-01-20 3:44 ` Jarkko Sakkinen
2021-01-14 15:19 ` [PATCH v3 04/10] certs: Fix blacklist flag type confusion Mickaël Salaün
2021-01-20 3:55 ` Jarkko Sakkinen
2021-01-20 11:15 ` Mickaël Salaün
2021-01-20 23:45 ` Jarkko Sakkinen
2021-01-14 15:19 ` [PATCH v3 05/10] certs: Replace K{U,G}IDT_INIT() with GLOBAL_ROOT_{U,G}ID Mickaël Salaün
2021-01-20 5:15 ` Jarkko Sakkinen
2021-01-20 11:17 ` Mickaël Salaün
2021-01-20 23:48 ` Jarkko Sakkinen
2021-01-14 15:19 ` [PATCH v3 06/10] certs: Make blacklist_vet_description() more strict Mickaël Salaün
2021-01-20 4:16 ` Jarkko Sakkinen
2021-01-20 11:23 ` Mickaël Salaün
2021-01-14 15:19 ` [PATCH v3 07/10] certs: Factor out the blacklist hash creation Mickaël Salaün
2021-01-14 15:19 ` [PATCH v3 08/10] certs: Check that builtin blacklist hashes are valid Mickaël Salaün
2021-01-20 5:19 ` Jarkko Sakkinen
2021-01-20 11:57 ` Mickaël Salaün
2021-01-20 23:53 ` Jarkko Sakkinen
2021-01-21 9:18 ` Mickaël Salaün
2021-01-21 15:21 ` Jarkko Sakkinen
2021-01-14 15:19 ` [PATCH v3 09/10] certs: Allow root user to append signed hashes to the blacklist keyring Mickaël Salaün
2021-01-15 13:06 ` Mimi Zohar
2021-01-20 5:23 ` Jarkko Sakkinen
2021-01-20 11:24 ` Mickaël Salaün
2021-01-14 15:19 ` [PATCH v3 10/10] tools/certs: Add print-cert-tbs-hash.sh Mickaël Salaün
2021-01-15 9:28 ` [PATCH v3 00/10] Enable root to update the blacklist keyring Jarkko Sakkinen
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=YAem+DjBR92WG+bK@kernel.org \
--to=jarkko@kernel.org \
--cc=davem@davemloft.net \
--cc=dhowells@redhat.com \
--cc=dwmw2@infradead.org \
--cc=herbert@gondor.apana.org.au \
--cc=jmorris@namei.org \
--cc=keyrings@vger.kernel.org \
--cc=linux-crypto@vger.kernel.org \
--cc=linux-integrity@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-security-module@vger.kernel.org \
--cc=mathstuf@gmail.com \
--cc=mic@digikod.net \
--cc=mic@linux.microsoft.com \
--cc=serge@hallyn.com \
--cc=zohar@linux.ibm.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).