bpf.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Jessica Yu <jeyu@kernel.org>
To: Kees Cook <keescook@chromium.org>
Cc: Dominik Czarnota <dominik.czarnota@trailofbits.com>,
	stable@vger.kernel.org,
	Linus Torvalds <torvalds@linux-foundation.org>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Andrew Morton <akpm@linux-foundation.org>,
	Alexei Starovoitov <ast@kernel.org>,
	Daniel Borkmann <daniel@iogearbox.net>,
	Martin KaFai Lau <kafai@fb.com>, Song Liu <songliubraving@fb.com>,
	Yonghong Song <yhs@fb.com>, Andrii Nakryiko <andriin@fb.com>,
	KP Singh <kpsingh@chromium.org>,
	"Naveen N. Rao" <naveen.n.rao@linux.ibm.com>,
	Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>,
	"David S. Miller" <davem@davemloft.net>,
	Masami Hiramatsu <mhiramat@kernel.org>,
	Jakub Kicinski <kuba@kernel.org>,
	"Steven Rostedt (VMware)" <rostedt@goodmis.org>,
	Dmitry Safonov <0x7f454c46@gmail.com>,
	Will Deacon <will@kernel.org>,
	Alexey Dobriyan <adobriyan@gmail.com>,
	Marc Zyngier <maz@kernel.org>,
	Masahiro Yamada <masahiroy@kernel.org>,
	Al Viro <viro@zeniv.linux.org.uk>,
	Matteo Croce <mcroce@redhat.com>,
	Edward Cree <ecree@solarflare.com>,
	Nicolas Dichtel <nicolas.dichtel@6wind.com>,
	Alexander Lobakin <alobakin@dlink.ru>,
	Thomas Richter <tmricht@linux.ibm.com>,
	Ingo Molnar <mingo@kernel.org>,
	netdev@vger.kernel.org, bpf@vger.kernel.org,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH 3/5] module: Do not expose section addresses to non-CAP_SYSLOG
Date: Wed, 8 Jul 2020 18:12:33 +0200	[thread overview]
Message-ID: <20200708161233.GB5609@linux-8ccs.fritz.box> (raw)
In-Reply-To: <20200702232638.2946421-4-keescook@chromium.org>

+++ Kees Cook [02/07/20 16:26 -0700]:
>The printing of section addresses in /sys/module/*/sections/* was not
>using the correct credentials to evaluate visibility.
>
>Before:
>
> # cat /sys/module/*/sections/.*text
> 0xffffffffc0458000
> ...
> # capsh --drop=CAP_SYSLOG -- -c "cat /sys/module/*/sections/.*text"
> 0xffffffffc0458000
> ...
>
>After:
>
> # cat /sys/module/*/sections/*.text
> 0xffffffffc0458000
> ...
> # capsh --drop=CAP_SYSLOG -- -c "cat /sys/module/*/sections/.*text"
> 0x0000000000000000
> ...
>
>Additionally replaces the existing (safe) /proc/modules check with
>file->f_cred for consistency.
>
>Cc: stable@vger.kernel.org
>Reported-by: Dominik Czarnota <dominik.czarnota@trailofbits.com>
>Fixes: be71eda5383f ("module: Fix display of wrong module .text address")
>Signed-off-by: Kees Cook <keescook@chromium.org>

Tested-by: Jessica Yu <jeyu@kernel.org>
Acked-by: Jessica Yu <jeyu@kernel.org>


  reply	other threads:[~2020-07-08 16:12 UTC|newest]

Thread overview: 16+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-07-02 23:26 [PATCH 0/5] Refactor kallsyms_show_value() users for correct cred Kees Cook
2020-07-02 23:26 ` [PATCH 1/5] kallsyms: Refactor kallsyms_show_value() to take cred Kees Cook
2020-07-02 23:26 ` [PATCH 2/5] module: Refactor section attr into bin attribute Kees Cook
2020-07-03  6:02   ` Greg Kroah-Hartman
2020-07-03 15:29     ` Kees Cook
2020-07-08 16:10   ` Jessica Yu
2020-07-02 23:26 ` [PATCH 3/5] module: Do not expose section addresses to non-CAP_SYSLOG Kees Cook
2020-07-08 16:12   ` Jessica Yu [this message]
2020-07-02 23:26 ` [PATCH 4/5] kprobes: Do not expose probe " Kees Cook
2020-07-03  1:00   ` Linus Torvalds
2020-07-03 15:13     ` Kees Cook
2020-07-03 15:50     ` Kees Cook
2020-07-05 20:10       ` Linus Torvalds
2020-07-05 20:19         ` Kees Cook
2020-07-10 14:09   ` Masami Hiramatsu
2020-07-02 23:26 ` [PATCH 5/5] bpf: Check correct cred for CAP_SYSLOG in bpf_dump_raw_ok() Kees Cook

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=20200708161233.GB5609@linux-8ccs.fritz.box \
    --to=jeyu@kernel.org \
    --cc=0x7f454c46@gmail.com \
    --cc=adobriyan@gmail.com \
    --cc=akpm@linux-foundation.org \
    --cc=alobakin@dlink.ru \
    --cc=andriin@fb.com \
    --cc=anil.s.keshavamurthy@intel.com \
    --cc=ast@kernel.org \
    --cc=bpf@vger.kernel.org \
    --cc=daniel@iogearbox.net \
    --cc=davem@davemloft.net \
    --cc=dominik.czarnota@trailofbits.com \
    --cc=ecree@solarflare.com \
    --cc=gregkh@linuxfoundation.org \
    --cc=kafai@fb.com \
    --cc=keescook@chromium.org \
    --cc=kpsingh@chromium.org \
    --cc=kuba@kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=masahiroy@kernel.org \
    --cc=maz@kernel.org \
    --cc=mcroce@redhat.com \
    --cc=mhiramat@kernel.org \
    --cc=mingo@kernel.org \
    --cc=naveen.n.rao@linux.ibm.com \
    --cc=netdev@vger.kernel.org \
    --cc=nicolas.dichtel@6wind.com \
    --cc=rostedt@goodmis.org \
    --cc=songliubraving@fb.com \
    --cc=stable@vger.kernel.org \
    --cc=tmricht@linux.ibm.com \
    --cc=torvalds@linux-foundation.org \
    --cc=viro@zeniv.linux.org.uk \
    --cc=will@kernel.org \
    --cc=yhs@fb.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).