From: Kees Cook <keescook@chromium.org>
To: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: linux-fbdev@vger.kernel.org,
Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org,
Jiri Slaby <jslaby@suse.com>,
syzbot <syzbot+017265e8553724e514e8@syzkaller.appspotmail.com>,
Dmitry Vyukov <dvyukov@google.com>
Subject: Re: [PATCH v3] vt: Reject zero-sized screen buffer size.
Date: Wed, 19 Aug 2020 22:07:46 +0000 [thread overview]
Message-ID: <202008191452.0278B57D43@keescook> (raw)
In-Reply-To: <20200712111013.11881-1-penguin-kernel@I-love.SAKURA.ne.jp>
On Sun, Jul 12, 2020 at 08:10:12PM +0900, Tetsuo Handa wrote:
> [...]
> @@ -1125,6 +1134,11 @@ int vc_allocate(unsigned int currcons) /* return 0 on success */
> if (!*vc->vc_uni_pagedir_loc)
> con_set_default_unimap(vc);
>
> + err = -EINVAL;
> + if (vc->vc_cols > VC_MAXCOL || vc->vc_rows > VC_MAXROW ||
> + vc->vc_screenbuf_size > KMALLOC_MAX_SIZE || !vc->vc_screenbuf_size)
> + goto err_free;
> + err = -ENOMEM;
> vc->vc_screenbuf = kzalloc(vc->vc_screenbuf_size, GFP_KERNEL);
> if (!vc->vc_screenbuf)
> goto err_free;
I realize this patch already landed, but I wanted to remind folks to
use the check_*_overflow() helpers, which can make a lot of this kind
of stuff easier to deal with.
For example, in this case, I think visual_init() could likely be changed
to return success/failure and do all the sanity checking:
if (check_shl_overflow(vc->vc_cols, 1, &vc->vc_size_row) ||
check_mul_overflow(vc->vc_rows, vc->vc_size_row, &vc->vc_screenbuf_size))
return -EINVAL;
--
Kees Cook
WARNING: multiple messages have this Message-ID (diff)
From: Kees Cook <keescook@chromium.org>
To: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: linux-fbdev@vger.kernel.org,
Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org,
Jiri Slaby <jslaby@suse.com>,
syzbot <syzbot+017265e8553724e514e8@syzkaller.appspotmail.com>,
Dmitry Vyukov <dvyukov@google.com>
Subject: Re: [PATCH v3] vt: Reject zero-sized screen buffer size.
Date: Wed, 19 Aug 2020 15:07:46 -0700 [thread overview]
Message-ID: <202008191452.0278B57D43@keescook> (raw)
In-Reply-To: <20200712111013.11881-1-penguin-kernel@I-love.SAKURA.ne.jp>
On Sun, Jul 12, 2020 at 08:10:12PM +0900, Tetsuo Handa wrote:
> [...]
> @@ -1125,6 +1134,11 @@ int vc_allocate(unsigned int currcons) /* return 0 on success */
> if (!*vc->vc_uni_pagedir_loc)
> con_set_default_unimap(vc);
>
> + err = -EINVAL;
> + if (vc->vc_cols > VC_MAXCOL || vc->vc_rows > VC_MAXROW ||
> + vc->vc_screenbuf_size > KMALLOC_MAX_SIZE || !vc->vc_screenbuf_size)
> + goto err_free;
> + err = -ENOMEM;
> vc->vc_screenbuf = kzalloc(vc->vc_screenbuf_size, GFP_KERNEL);
> if (!vc->vc_screenbuf)
> goto err_free;
I realize this patch already landed, but I wanted to remind folks to
use the check_*_overflow() helpers, which can make a lot of this kind
of stuff easier to deal with.
For example, in this case, I think visual_init() could likely be changed
to return success/failure and do all the sanity checking:
if (check_shl_overflow(vc->vc_cols, 1, &vc->vc_size_row) ||
check_mul_overflow(vc->vc_rows, vc->vc_size_row, &vc->vc_screenbuf_size))
return -EINVAL;
--
Kees Cook
_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel
WARNING: multiple messages have this Message-ID (diff)
From: Kees Cook <keescook@chromium.org>
To: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
Jiri Slaby <jslaby@suse.com>, Dmitry Vyukov <dvyukov@google.com>,
dri-devel@lists.freedesktop.org, linux-fbdev@vger.kernel.org,
linux-kernel@vger.kernel.org,
syzbot <syzbot+017265e8553724e514e8@syzkaller.appspotmail.com>
Subject: Re: [PATCH v3] vt: Reject zero-sized screen buffer size.
Date: Wed, 19 Aug 2020 15:07:46 -0700 [thread overview]
Message-ID: <202008191452.0278B57D43@keescook> (raw)
In-Reply-To: <20200712111013.11881-1-penguin-kernel@I-love.SAKURA.ne.jp>
On Sun, Jul 12, 2020 at 08:10:12PM +0900, Tetsuo Handa wrote:
> [...]
> @@ -1125,6 +1134,11 @@ int vc_allocate(unsigned int currcons) /* return 0 on success */
> if (!*vc->vc_uni_pagedir_loc)
> con_set_default_unimap(vc);
>
> + err = -EINVAL;
> + if (vc->vc_cols > VC_MAXCOL || vc->vc_rows > VC_MAXROW ||
> + vc->vc_screenbuf_size > KMALLOC_MAX_SIZE || !vc->vc_screenbuf_size)
> + goto err_free;
> + err = -ENOMEM;
> vc->vc_screenbuf = kzalloc(vc->vc_screenbuf_size, GFP_KERNEL);
> if (!vc->vc_screenbuf)
> goto err_free;
I realize this patch already landed, but I wanted to remind folks to
use the check_*_overflow() helpers, which can make a lot of this kind
of stuff easier to deal with.
For example, in this case, I think visual_init() could likely be changed
to return success/failure and do all the sanity checking:
if (check_shl_overflow(vc->vc_cols, 1, &vc->vc_size_row) ||
check_mul_overflow(vc->vc_rows, vc->vc_size_row, &vc->vc_screenbuf_size))
return -EINVAL;
--
Kees Cook
next prev parent reply other threads:[~2020-08-19 22:07 UTC|newest]
Thread overview: 77+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-07-10 5:53 [PATCH] vt: Reject zero-sized screen buffer size Tetsuo Handa
2020-07-10 5:56 ` fbconsole needs more parameter validations Tetsuo Handa
2020-07-10 5:56 ` Tetsuo Handa
2020-07-10 5:56 ` Tetsuo Handa
2020-07-10 10:56 ` Greg Kroah-Hartman
2020-07-10 10:56 ` Greg Kroah-Hartman
2020-07-10 10:56 ` Greg Kroah-Hartman
2020-07-11 6:16 ` Tetsuo Handa
2020-07-11 6:16 ` Tetsuo Handa
2020-07-11 6:16 ` Tetsuo Handa
2020-07-11 11:08 ` Tetsuo Handa
2020-07-11 11:08 ` Tetsuo Handa
2020-07-11 11:08 ` Tetsuo Handa
2020-07-12 11:10 ` [PATCH v3] vt: Reject zero-sized screen buffer size Tetsuo Handa
2020-07-12 11:10 ` Tetsuo Handa
2020-07-12 11:10 ` Tetsuo Handa
2020-07-12 11:10 ` [PATCH] fbdev: Detect integer underflow at "struct fbcon_ops"->clear_margins Tetsuo Handa
2020-07-12 11:10 ` Tetsuo Handa
2020-07-12 11:10 ` Tetsuo Handa
2020-07-14 7:22 ` Bartlomiej Zolnierkiewicz
2020-07-14 7:22 ` Bartlomiej Zolnierkiewicz
2020-07-14 7:22 ` Bartlomiej Zolnierkiewicz
2020-07-14 10:27 ` Tetsuo Handa
2020-07-14 10:27 ` Tetsuo Handa
2020-07-14 10:27 ` Tetsuo Handa
2020-07-14 13:37 ` Tetsuo Handa
2020-07-14 13:37 ` Tetsuo Handa
2020-07-14 13:37 ` Tetsuo Handa
2020-07-15 1:51 ` [PATCH v2] " Tetsuo Handa
2020-07-15 1:51 ` Tetsuo Handa
2020-07-15 1:51 ` Tetsuo Handa
2020-07-15 9:48 ` Dan Carpenter
2020-07-15 9:48 ` Dan Carpenter
2020-07-15 9:48 ` Dan Carpenter
2020-07-15 11:17 ` Tetsuo Handa
2020-07-15 11:17 ` Tetsuo Handa
2020-07-15 11:17 ` Tetsuo Handa
2020-07-15 14:02 ` Tetsuo Handa
2020-07-15 14:02 ` Tetsuo Handa
2020-07-15 14:02 ` Tetsuo Handa
2020-07-15 15:12 ` Dan Carpenter
2020-07-15 15:12 ` Dan Carpenter
2020-07-15 15:12 ` Dan Carpenter
2020-07-15 15:29 ` Tetsuo Handa
2020-07-15 15:29 ` Tetsuo Handa
2020-07-15 15:29 ` Tetsuo Handa
2020-07-16 10:00 ` Daniel Vetter
2020-07-16 10:00 ` Daniel Vetter
2020-07-16 10:00 ` Daniel Vetter
2020-07-16 11:27 ` Tetsuo Handa
2020-07-16 11:27 ` Tetsuo Handa
2020-07-16 11:27 ` Tetsuo Handa
2020-07-21 16:08 ` Greg Kroah-Hartman
2020-07-21 16:08 ` Greg Kroah-Hartman
2020-07-21 16:08 ` Greg Kroah-Hartman
2020-07-22 8:07 ` Daniel Vetter
2020-07-22 8:07 ` Daniel Vetter
2020-07-22 8:07 ` Daniel Vetter
2020-07-23 14:21 ` Greg Kroah-Hartman
2020-07-23 14:21 ` Greg Kroah-Hartman
2020-07-23 14:21 ` Greg Kroah-Hartman
2020-07-24 8:28 ` Bartlomiej Zolnierkiewicz
2020-07-24 8:28 ` Bartlomiej Zolnierkiewicz
2020-07-24 8:28 ` Bartlomiej Zolnierkiewicz
2020-07-14 17:15 ` [PATCH] " George Kennedy
2020-07-15 0:24 ` Tetsuo Handa
2020-07-15 0:24 ` Tetsuo Handa
2020-07-15 0:24 ` Tetsuo Handa
2020-08-19 22:07 ` Kees Cook [this message]
2020-08-19 22:07 ` [PATCH v3] vt: Reject zero-sized screen buffer size Kees Cook
2020-08-19 22:07 ` Kees Cook
2020-07-10 10:55 ` [PATCH] " Greg Kroah-Hartman
2020-07-10 11:31 ` Tetsuo Handa
2020-07-10 11:36 ` Greg Kroah-Hartman
2020-07-10 14:34 ` [PATCH v2] " Tetsuo Handa
2020-07-20 15:40 ` Brooke Basile
2020-07-20 23:00 ` Tetsuo Handa
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=202008191452.0278B57D43@keescook \
--to=keescook@chromium.org \
--cc=dri-devel@lists.freedesktop.org \
--cc=dvyukov@google.com \
--cc=gregkh@linuxfoundation.org \
--cc=jslaby@suse.com \
--cc=linux-fbdev@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=penguin-kernel@I-love.SAKURA.ne.jp \
--cc=syzbot+017265e8553724e514e8@syzkaller.appspotmail.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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.