Message ID | 20210616185938.1225218-1-keescook@chromium.org (mailing list archive) |
---|---|
State | New |
Delegated to: | Laurent Pinchart |
Headers |
Received: from vger.kernel.org ([23.128.96.18]) by www.linuxtv.org with esmtp (Exim 4.92) (envelope-from <linux-media-owner@vger.kernel.org>) id 1ltalM-0023lH-TM; Wed, 16 Jun 2021 18:59:46 +0000 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232041AbhFPTBt (ORCPT <rfc822;mkrufky@linuxtv.org> + 1 other); Wed, 16 Jun 2021 15:01:49 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57750 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230269AbhFPTBs (ORCPT <rfc822;linux-media@vger.kernel.org>); Wed, 16 Jun 2021 15:01:48 -0400 Received: from mail-pj1-x1030.google.com (mail-pj1-x1030.google.com [IPv6:2607:f8b0:4864:20::1030]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 727C3C06175F for <linux-media@vger.kernel.org>; Wed, 16 Jun 2021 11:59:42 -0700 (PDT) Received: by mail-pj1-x1030.google.com with SMTP id s17-20020a17090a8811b029016e89654f93so4578029pjn.1 for <linux-media@vger.kernel.org>; Wed, 16 Jun 2021 11:59:42 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=0Os+MCmeoTC6JTgDL5U7Se6Y1Owhx1D5nB8TA3sfO0A=; b=PMHKY+racXbZwjt8VBIGr7U8kMdBVXLY6G4EFPdDJKwIidRT9b6yETnFVjeDb7E5O/ TtUhPZ1an4c2E0bGKAGNBtgapJu6+++WrtL6J1KzCAD4Br/4UaKort4/w5MNMp8QQ0YG GFUAQ2i768btCuvIyKny70Q0KHIKoxeeuOdcE= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=0Os+MCmeoTC6JTgDL5U7Se6Y1Owhx1D5nB8TA3sfO0A=; b=jqQVO0fwOx5Eu1ML8wArZ4OnHnUs3oW4h4hZi5zThlnfdh+YhuC5eycMRZQd/DhYkQ 3E79u44dMNcOux1faBEg1UVfMwlBA6hQC5xGLgVd+xHbNFuAMo3XaN/IsYhVhUG8cgzQ YFczmmAGiKqFxdKKoE5UccGhwTWX/oPQ637MCkEC3zPbR2O3UjUviyT3Ck+aVbjNUJL0 WUtwWAWaSV0rfTE3noRcWPgKSoAf4a2DtgldODYIdcLdoPtUHkntCEPLaI08K6vfi8Uw iYOgIQeCGavPBD7OwfQkIQH0Q6n1aX1piayttyExPglp+fBU995SvH3QKMsNFD5GZWMp bXkw== X-Gm-Message-State: AOAM532l8lCGm/no/gQGo8DnxldMucROwhBpmVJpei35mgfdXNFTvbUC e50yz7m4p+4+DAwnEtyJEazyZQ== X-Google-Smtp-Source: ABdhPJwmECO30Z/38e9jlyzsxxZVC0/UVuE8SucOrFpRiR5yQtebrZNUfxc0IJy+483gdlwwb8F7lQ== X-Received: by 2002:a17:90a:df13:: with SMTP id gp19mr1288730pjb.11.1623869981776; Wed, 16 Jun 2021 11:59:41 -0700 (PDT) Received: from www.outflux.net (smtp.outflux.net. [198.145.64.163]) by smtp.gmail.com with ESMTPSA id b18sm2831829pfb.131.2021.06.16.11.59.40 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 16 Jun 2021 11:59:41 -0700 (PDT) From: Kees Cook <keescook@chromium.org> To: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Cc: Kees Cook <keescook@chromium.org>, Arnd Bergmann <arnd@arndb.de>, "Gustavo A. R. Silva" <gustavoars@kernel.org>, Laurent Pinchart <laurent.pinchart@ideasonboard.com>, Sakari Ailus <sakari.ailus@linux.intel.com>, linux-kernel@vger.kernel.org, linux-media@vger.kernel.org Subject: [PATCH] media: omap3isp: Extract struct group for memcpy() region Date: Wed, 16 Jun 2021 11:59:38 -0700 Message-Id: <20210616185938.1225218-1-keescook@chromium.org> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 X-Patch-Hashes: v=1; h=sha256; g=910ed8959b76f13dd879af35818c96acb0e3b882; i=ZZImBpmvoNoFnzG2oXXjjeAWeziu9KmJxVF7qJ1oTSM=; m=d9AzytSqyDqMH7aQlTbCNKT7yao+v2IBcpVUdy3sz2A=; p=RkrWXBiNXbxKMFNfgHmuMepip9a6kkWMRqHj0Y8cJkY= X-Patch-Sig: m=pgp; i=keescook@chromium.org; s=0x0x8972F4DFDC6DC026; b=iQIzBAABCgAdFiEEpcP2jyKd1g9yPm4TiXL039xtwCYFAmDKShkACgkQiXL039xtwCbw2A//VK3 l4G1F97xEfJuIb581uFJle571JO82dkVJPpzb+cKPJakYr8mHCdim3lXI9ehrb7LzRz7bnDvo1GfX 2xcNltTikKk7MeqDk9CQOSCNhCJ32qUorsyasdHXm03wewlltm6k8KQEi/crZepC1MDzsCOXRyUvh szWiCXigNOwf4c9cBACLMk9efLWZTYnmx8+rIfDWlsunCVxfBM8/VJ0bi8gCKB6TW8miR/aoEjv+H SFAeSwjKMpeaoKrkpI9sLgJgcqrn5F3uYcLpRCFOK4JG4mote5x104Mu7cOp99lfKDzsPnCkbxvXJ XJb5+doaIxlZ00qPsPYPFgVZwpilobdSyVait/8n6BV3x1umYkEq6BwVv9LoouCDu2QVbZfcO8udq md/XGPEIbfXbGGYCAVEBEAD6YQPaUeSDjr+ToaKoFoiYRMnP845WGx99vk3a9IEHFVI2YJRDpigaQ h29lRUIedpT/A1VdktoMLWYHGWfxYvGeC8+pXCYmhNtMm5FK0Y9FZMWOWlbq1YLub2kB3h7xOOJMS niYLcm5QA1iSjKnbzRkrps3aNP1X+ilOFjTHI7kRUjmvcnsVuQZpO5tBfKpCXeQwEWvEThLEGKbUv e9luzWFxN6fF1A7XEBOJNQiqf6xyk9CaQr3Ad9g3vu4PfnTMvr3bRz02IMOovOEQ= Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: <linux-media.vger.kernel.org> X-Mailing-List: linux-media@vger.kernel.org X-LSpam-Score: -3.2 (---) X-LSpam-Report: No, score=-3.2 required=5.0 tests=BAYES_00=-1.9,DKIMWL_WL_HIGH=0.001,DKIM_SIGNED=0.1,DKIM_VALID=-0.1,DKIM_VALID_AU=-0.1,HEADER_FROM_DIFFERENT_DOMAINS=0.5,MAILING_LIST_MULTI=-1,RCVD_IN_DNSWL_LOW=-0.7 autolearn=ham autolearn_force=no |
Series |
media: omap3isp: Extract struct group for memcpy() region
|
|
Commit Message
Kees Cook
June 16, 2021, 6:59 p.m. UTC
Avoid writing past the end of a structure member by wrapping the target
region in a common named structure. This additionally fixes a
misalignment of the copy (since the size of "buf" changes between 64-bit
and 32-bit).
I actually think this code is completely unused in the real world:
I don't think it could have ever worked, as it would either always
fail (with an uninitialized data->buf_size) or would cause corruption
in userspace due to the copy_to_user() in the call path against an
uninitialized data->buf value:
omap3isp_stat_request_statistics_time32(...)
struct omap3isp_stat_data data64;
...
omap3isp_stat_request_statistics(stat, &data64);
int omap3isp_stat_request_statistics(struct ispstat *stat,
struct omap3isp_stat_data *data)
...
buf = isp_stat_buf_get(stat, data);
static struct ispstat_buffer *isp_stat_buf_get(struct ispstat *stat,
struct omap3isp_stat_data *data)
...
if (buf->buf_size > data->buf_size) {
...
return ERR_PTR(-EINVAL);
}
...
rval = copy_to_user(data->buf,
buf->virt_addr,
buf->buf_size);
Regardless, additionally initialize data64 to be zero-filled to avoid
undefined behavior.
Fixes: 378e3f81cb56 ("media: omap3isp: support 64-bit version of omap3isp_stat_data")
Signed-off-by: Kees Cook <keescook@chromium.org>
---
drivers/media/platform/omap3isp/ispstat.c | 5 +--
include/uapi/linux/omap3isp.h | 44 +++++++++++++++++------
2 files changed, 36 insertions(+), 13 deletions(-)
Comments
Hi Kees, Thank you for the patch. On Wed, Jun 16, 2021 at 11:59:38AM -0700, Kees Cook wrote: > Avoid writing past the end of a structure member by wrapping the target > region in a common named structure. This additionally fixes a > misalignment of the copy (since the size of "buf" changes between 64-bit > and 32-bit). Could you have been mislead by the data64 name ? The difference between omap3isp_stat_data_time and omap3isp_stat_data_time32 is the size of the ts field, using 32-bit timestamps with legacy userspace, and 64-bit timestamps with more recent userspace. In both cases we're dealing with a 32-bit platform, as the omap3isp is not used in any 64-bit ARM SoC. The size of void __user *buf is thus 4 bytes in all cases, as is __u32 buf. > I actually think this code is completely unused in the real world: > I don't think it could have ever worked, as it would either always > fail (with an uninitialized data->buf_size) or would cause corruption > in userspace due to the copy_to_user() in the call path against an > uninitialized data->buf value: > > omap3isp_stat_request_statistics_time32(...) > struct omap3isp_stat_data data64; > ... > omap3isp_stat_request_statistics(stat, &data64); > > int omap3isp_stat_request_statistics(struct ispstat *stat, > struct omap3isp_stat_data *data) > ... > buf = isp_stat_buf_get(stat, data); > > static struct ispstat_buffer *isp_stat_buf_get(struct ispstat *stat, > struct omap3isp_stat_data *data) > ... > if (buf->buf_size > data->buf_size) { > ... > return ERR_PTR(-EINVAL); > } > ... > rval = copy_to_user(data->buf, > buf->virt_addr, > buf->buf_size); > > Regardless, additionally initialize data64 to be zero-filled to avoid > undefined behavior. > > Fixes: 378e3f81cb56 ("media: omap3isp: support 64-bit version of omap3isp_stat_data") > Signed-off-by: Kees Cook <keescook@chromium.org> > --- > drivers/media/platform/omap3isp/ispstat.c | 5 +-- > include/uapi/linux/omap3isp.h | 44 +++++++++++++++++------ > 2 files changed, 36 insertions(+), 13 deletions(-) > > diff --git a/drivers/media/platform/omap3isp/ispstat.c b/drivers/media/platform/omap3isp/ispstat.c > index 5b9b57f4d9bf..ea8222fed38e 100644 > --- a/drivers/media/platform/omap3isp/ispstat.c > +++ b/drivers/media/platform/omap3isp/ispstat.c > @@ -512,7 +512,7 @@ int omap3isp_stat_request_statistics(struct ispstat *stat, > int omap3isp_stat_request_statistics_time32(struct ispstat *stat, > struct omap3isp_stat_data_time32 *data) > { > - struct omap3isp_stat_data data64; > + struct omap3isp_stat_data data64 = { }; > int ret; > > ret = omap3isp_stat_request_statistics(stat, &data64); > @@ -521,7 +521,8 @@ int omap3isp_stat_request_statistics_time32(struct ispstat *stat, > > data->ts.tv_sec = data64.ts.tv_sec; > data->ts.tv_usec = data64.ts.tv_usec; > - memcpy(&data->buf, &data64.buf, sizeof(*data) - sizeof(data->ts)); > + data->buf = (uintptr_t)data64.buf; > + memcpy(&data->frame, &data64.buf, sizeof(data->frame)); > > return 0; > } > diff --git a/include/uapi/linux/omap3isp.h b/include/uapi/linux/omap3isp.h > index 87b55755f4ff..0a16af91621f 100644 > --- a/include/uapi/linux/omap3isp.h > +++ b/include/uapi/linux/omap3isp.h > @@ -159,13 +159,25 @@ struct omap3isp_h3a_aewb_config { > }; > > /** > - * struct omap3isp_stat_data - Statistic data sent to or received from user > - * @ts: Timestamp of returned framestats. > - * @buf: Pointer to pass to user. > + * struct omap3isp_stat_frame - Statistic data without timestamp nor pointer. > + * @buf_size: Size of buffer. > * @frame_number: Frame number of requested stats. > * @cur_frame: Current frame number being processed. > * @config_counter: Number of the configuration associated with the data. > */ > +struct omap3isp_stat_frame { > + __u32 buf_size; > + __u16 frame_number; > + __u16 cur_frame; > + __u16 config_counter; > +}; > + > +/** > + * struct omap3isp_stat_data - Statistic data sent to or received from user > + * @ts: Timestamp of returned framestats. > + * @buf: Pointer to pass to user. > + * @frame: Statistic data for frame. > + */ > struct omap3isp_stat_data { > #ifdef __KERNEL__ > struct { > @@ -176,10 +188,15 @@ struct omap3isp_stat_data { > struct timeval ts; > #endif > void __user *buf; > - __u32 buf_size; > - __u16 frame_number; > - __u16 cur_frame; > - __u16 config_counter; > + union { > + struct { > + __u32 buf_size; > + __u16 frame_number; > + __u16 cur_frame; > + __u16 config_counter; > + }; > + struct omap3isp_stat_frame frame; > + }; > }; > > #ifdef __KERNEL__ > @@ -189,10 +206,15 @@ struct omap3isp_stat_data_time32 { > __s32 tv_usec; > } ts; > __u32 buf; > - __u32 buf_size; > - __u16 frame_number; > - __u16 cur_frame; > - __u16 config_counter; > + union { > + struct { > + __u32 buf_size; > + __u16 frame_number; > + __u16 cur_frame; > + __u16 config_counter; > + }; > + struct omap3isp_stat_frame frame; > + }; > }; > #endif >
On Wed, Jun 16, 2021 at 10:43:03PM +0300, Laurent Pinchart wrote: > Hi Kees, > > Thank you for the patch. > > On Wed, Jun 16, 2021 at 11:59:38AM -0700, Kees Cook wrote: > > Avoid writing past the end of a structure member by wrapping the target > > region in a common named structure. This additionally fixes a > > misalignment of the copy (since the size of "buf" changes between 64-bit > > and 32-bit). > > Could you have been mislead by the data64 name ? The difference between > omap3isp_stat_data_time and omap3isp_stat_data_time32 is the size of the > ts field, using 32-bit timestamps with legacy userspace, and 64-bit > timestamps with more recent userspace. In both cases we're dealing with > a 32-bit platform, as the omap3isp is not used in any 64-bit ARM SoC. > The size of void __user *buf is thus 4 bytes in all cases, as is __u32 > buf. Ah, yes, that's true. I was hitting this on arm64 builds (CONFIG_COMPILE_TEST) where __user *buf is 64-bit. So, the "additionally fixes" bit above is misleading in the sense that nothing was ever built in the real world like that. The patch still fixes the compile-time warnings, though. However, I don't think anything actually uses any of this code regardless. ;) -Kees > > > I actually think this code is completely unused in the real world: > > I don't think it could have ever worked, as it would either always > > fail (with an uninitialized data->buf_size) or would cause corruption > > in userspace due to the copy_to_user() in the call path against an > > uninitialized data->buf value: > > > > omap3isp_stat_request_statistics_time32(...) > > struct omap3isp_stat_data data64; > > ... > > omap3isp_stat_request_statistics(stat, &data64); > > > > int omap3isp_stat_request_statistics(struct ispstat *stat, > > struct omap3isp_stat_data *data) > > ... > > buf = isp_stat_buf_get(stat, data); > > > > static struct ispstat_buffer *isp_stat_buf_get(struct ispstat *stat, > > struct omap3isp_stat_data *data) > > ... > > if (buf->buf_size > data->buf_size) { > > ... > > return ERR_PTR(-EINVAL); > > } > > ... > > rval = copy_to_user(data->buf, > > buf->virt_addr, > > buf->buf_size); > > > > Regardless, additionally initialize data64 to be zero-filled to avoid > > undefined behavior. > > > > Fixes: 378e3f81cb56 ("media: omap3isp: support 64-bit version of omap3isp_stat_data") > > Signed-off-by: Kees Cook <keescook@chromium.org> > > --- > > drivers/media/platform/omap3isp/ispstat.c | 5 +-- > > include/uapi/linux/omap3isp.h | 44 +++++++++++++++++------ > > 2 files changed, 36 insertions(+), 13 deletions(-) > > > > diff --git a/drivers/media/platform/omap3isp/ispstat.c b/drivers/media/platform/omap3isp/ispstat.c > > index 5b9b57f4d9bf..ea8222fed38e 100644 > > --- a/drivers/media/platform/omap3isp/ispstat.c > > +++ b/drivers/media/platform/omap3isp/ispstat.c > > @@ -512,7 +512,7 @@ int omap3isp_stat_request_statistics(struct ispstat *stat, > > int omap3isp_stat_request_statistics_time32(struct ispstat *stat, > > struct omap3isp_stat_data_time32 *data) > > { > > - struct omap3isp_stat_data data64; > > + struct omap3isp_stat_data data64 = { }; > > int ret; > > > > ret = omap3isp_stat_request_statistics(stat, &data64); > > @@ -521,7 +521,8 @@ int omap3isp_stat_request_statistics_time32(struct ispstat *stat, > > > > data->ts.tv_sec = data64.ts.tv_sec; > > data->ts.tv_usec = data64.ts.tv_usec; > > - memcpy(&data->buf, &data64.buf, sizeof(*data) - sizeof(data->ts)); > > + data->buf = (uintptr_t)data64.buf; > > + memcpy(&data->frame, &data64.buf, sizeof(data->frame)); > > > > return 0; > > } > > diff --git a/include/uapi/linux/omap3isp.h b/include/uapi/linux/omap3isp.h > > index 87b55755f4ff..0a16af91621f 100644 > > --- a/include/uapi/linux/omap3isp.h > > +++ b/include/uapi/linux/omap3isp.h > > @@ -159,13 +159,25 @@ struct omap3isp_h3a_aewb_config { > > }; > > > > /** > > - * struct omap3isp_stat_data - Statistic data sent to or received from user > > - * @ts: Timestamp of returned framestats. > > - * @buf: Pointer to pass to user. > > + * struct omap3isp_stat_frame - Statistic data without timestamp nor pointer. > > + * @buf_size: Size of buffer. > > * @frame_number: Frame number of requested stats. > > * @cur_frame: Current frame number being processed. > > * @config_counter: Number of the configuration associated with the data. > > */ > > +struct omap3isp_stat_frame { > > + __u32 buf_size; > > + __u16 frame_number; > > + __u16 cur_frame; > > + __u16 config_counter; > > +}; > > + > > +/** > > + * struct omap3isp_stat_data - Statistic data sent to or received from user > > + * @ts: Timestamp of returned framestats. > > + * @buf: Pointer to pass to user. > > + * @frame: Statistic data for frame. > > + */ > > struct omap3isp_stat_data { > > #ifdef __KERNEL__ > > struct { > > @@ -176,10 +188,15 @@ struct omap3isp_stat_data { > > struct timeval ts; > > #endif > > void __user *buf; > > - __u32 buf_size; > > - __u16 frame_number; > > - __u16 cur_frame; > > - __u16 config_counter; > > + union { > > + struct { > > + __u32 buf_size; > > + __u16 frame_number; > > + __u16 cur_frame; > > + __u16 config_counter; > > + }; > > + struct omap3isp_stat_frame frame; > > + }; > > }; > > > > #ifdef __KERNEL__ > > @@ -189,10 +206,15 @@ struct omap3isp_stat_data_time32 { > > __s32 tv_usec; > > } ts; > > __u32 buf; > > - __u32 buf_size; > > - __u16 frame_number; > > - __u16 cur_frame; > > - __u16 config_counter; > > + union { > > + struct { > > + __u32 buf_size; > > + __u16 frame_number; > > + __u16 cur_frame; > > + __u16 config_counter; > > + }; > > + struct omap3isp_stat_frame frame; > > + }; > > }; > > #endif > > > > -- > Regards, > > Laurent Pinchart
Hi Kees, On Wed, Jun 16, 2021 at 09:22:23PM -0700, Kees Cook wrote: > On Wed, Jun 16, 2021 at 10:43:03PM +0300, Laurent Pinchart wrote: > > On Wed, Jun 16, 2021 at 11:59:38AM -0700, Kees Cook wrote: > > > Avoid writing past the end of a structure member by wrapping the target > > > region in a common named structure. This additionally fixes a > > > misalignment of the copy (since the size of "buf" changes between 64-bit > > > and 32-bit). > > > > Could you have been mislead by the data64 name ? The difference between > > omap3isp_stat_data_time and omap3isp_stat_data_time32 is the size of the > > ts field, using 32-bit timestamps with legacy userspace, and 64-bit > > timestamps with more recent userspace. In both cases we're dealing with > > a 32-bit platform, as the omap3isp is not used in any 64-bit ARM SoC. > > The size of void __user *buf is thus 4 bytes in all cases, as is __u32 > > buf. > > Ah, yes, that's true. I was hitting this on arm64 builds > (CONFIG_COMPILE_TEST) where __user *buf is 64-bit. So, the "additionally > fixes" bit above is misleading in the sense that nothing was ever built > in the real world like that. > > The patch still fixes the compile-time warnings, though. I What's the compile-time warning ? I tried compiling the driver for ARM64 and didn't notice any. > However, I don't think anything actually uses any of this code > regardless. ;) > > > > I actually think this code is completely unused in the real world: > > > I don't think it could have ever worked, as it would either always > > > fail (with an uninitialized data->buf_size) or would cause corruption > > > in userspace due to the copy_to_user() in the call path against an > > > uninitialized data->buf value: > > > > > > omap3isp_stat_request_statistics_time32(...) > > > struct omap3isp_stat_data data64; > > > ... > > > omap3isp_stat_request_statistics(stat, &data64); > > > > > > int omap3isp_stat_request_statistics(struct ispstat *stat, > > > struct omap3isp_stat_data *data) > > > ... > > > buf = isp_stat_buf_get(stat, data); > > > > > > static struct ispstat_buffer *isp_stat_buf_get(struct ispstat *stat, > > > struct omap3isp_stat_data *data) > > > ... > > > if (buf->buf_size > data->buf_size) { > > > ... > > > return ERR_PTR(-EINVAL); > > > } > > > ... > > > rval = copy_to_user(data->buf, > > > buf->virt_addr, > > > buf->buf_size); > > > > > > Regardless, additionally initialize data64 to be zero-filled to avoid > > > undefined behavior. > > > > > > Fixes: 378e3f81cb56 ("media: omap3isp: support 64-bit version of omap3isp_stat_data") > > > Signed-off-by: Kees Cook <keescook@chromium.org> > > > --- > > > drivers/media/platform/omap3isp/ispstat.c | 5 +-- > > > include/uapi/linux/omap3isp.h | 44 +++++++++++++++++------ > > > 2 files changed, 36 insertions(+), 13 deletions(-) > > > > > > diff --git a/drivers/media/platform/omap3isp/ispstat.c b/drivers/media/platform/omap3isp/ispstat.c > > > index 5b9b57f4d9bf..ea8222fed38e 100644 > > > --- a/drivers/media/platform/omap3isp/ispstat.c > > > +++ b/drivers/media/platform/omap3isp/ispstat.c > > > @@ -512,7 +512,7 @@ int omap3isp_stat_request_statistics(struct ispstat *stat, > > > int omap3isp_stat_request_statistics_time32(struct ispstat *stat, > > > struct omap3isp_stat_data_time32 *data) > > > { > > > - struct omap3isp_stat_data data64; > > > + struct omap3isp_stat_data data64 = { }; > > > int ret; > > > > > > ret = omap3isp_stat_request_statistics(stat, &data64); > > > @@ -521,7 +521,8 @@ int omap3isp_stat_request_statistics_time32(struct ispstat *stat, > > > > > > data->ts.tv_sec = data64.ts.tv_sec; > > > data->ts.tv_usec = data64.ts.tv_usec; > > > - memcpy(&data->buf, &data64.buf, sizeof(*data) - sizeof(data->ts)); > > > + data->buf = (uintptr_t)data64.buf; > > > + memcpy(&data->frame, &data64.buf, sizeof(data->frame)); > > > > > > return 0; > > > } > > > diff --git a/include/uapi/linux/omap3isp.h b/include/uapi/linux/omap3isp.h > > > index 87b55755f4ff..0a16af91621f 100644 > > > --- a/include/uapi/linux/omap3isp.h > > > +++ b/include/uapi/linux/omap3isp.h > > > @@ -159,13 +159,25 @@ struct omap3isp_h3a_aewb_config { > > > }; > > > > > > /** > > > - * struct omap3isp_stat_data - Statistic data sent to or received from user > > > - * @ts: Timestamp of returned framestats. > > > - * @buf: Pointer to pass to user. > > > + * struct omap3isp_stat_frame - Statistic data without timestamp nor pointer. > > > + * @buf_size: Size of buffer. > > > * @frame_number: Frame number of requested stats. > > > * @cur_frame: Current frame number being processed. > > > * @config_counter: Number of the configuration associated with the data. > > > */ > > > +struct omap3isp_stat_frame { > > > + __u32 buf_size; > > > + __u16 frame_number; > > > + __u16 cur_frame; > > > + __u16 config_counter; > > > +}; > > > + > > > +/** > > > + * struct omap3isp_stat_data - Statistic data sent to or received from user > > > + * @ts: Timestamp of returned framestats. > > > + * @buf: Pointer to pass to user. > > > + * @frame: Statistic data for frame. > > > + */ > > > struct omap3isp_stat_data { > > > #ifdef __KERNEL__ > > > struct { > > > @@ -176,10 +188,15 @@ struct omap3isp_stat_data { > > > struct timeval ts; > > > #endif > > > void __user *buf; > > > - __u32 buf_size; > > > - __u16 frame_number; > > > - __u16 cur_frame; > > > - __u16 config_counter; > > > + union { > > > + struct { > > > + __u32 buf_size; > > > + __u16 frame_number; > > > + __u16 cur_frame; > > > + __u16 config_counter; > > > + }; > > > + struct omap3isp_stat_frame frame; > > > + }; > > > }; > > > > > > #ifdef __KERNEL__ > > > @@ -189,10 +206,15 @@ struct omap3isp_stat_data_time32 { > > > __s32 tv_usec; > > > } ts; > > > __u32 buf; > > > - __u32 buf_size; > > > - __u16 frame_number; > > > - __u16 cur_frame; > > > - __u16 config_counter; > > > + union { > > > + struct { > > > + __u32 buf_size; > > > + __u16 frame_number; > > > + __u16 cur_frame; > > > + __u16 config_counter; > > > + }; > > > + struct omap3isp_stat_frame frame; > > > + }; > > > }; > > > #endif > > >
On Thu, Jun 24, 2021 at 01:12:11AM +0300, Laurent Pinchart wrote: > Hi Kees, > > On Wed, Jun 16, 2021 at 09:22:23PM -0700, Kees Cook wrote: > > On Wed, Jun 16, 2021 at 10:43:03PM +0300, Laurent Pinchart wrote: > > > On Wed, Jun 16, 2021 at 11:59:38AM -0700, Kees Cook wrote: > > > > Avoid writing past the end of a structure member by wrapping the target > > > > region in a common named structure. This additionally fixes a > > > > misalignment of the copy (since the size of "buf" changes between 64-bit > > > > and 32-bit). > > > > > > Could you have been mislead by the data64 name ? The difference between > > > omap3isp_stat_data_time and omap3isp_stat_data_time32 is the size of the > > > ts field, using 32-bit timestamps with legacy userspace, and 64-bit > > > timestamps with more recent userspace. In both cases we're dealing with > > > a 32-bit platform, as the omap3isp is not used in any 64-bit ARM SoC. > > > The size of void __user *buf is thus 4 bytes in all cases, as is __u32 > > > buf. > > > > Ah, yes, that's true. I was hitting this on arm64 builds > > (CONFIG_COMPILE_TEST) where __user *buf is 64-bit. So, the "additionally > > fixes" bit above is misleading in the sense that nothing was ever built > > in the real world like that. > > > > The patch still fixes the compile-time warnings, though. > > I What's the compile-time warning ? I tried compiling the driver for > ARM64 and didn't notice any. Sorry, I didn't include the background well enough in the commit log, but it's part of a tightening of memcpy() under FORTIFY_SOURCE and also -Warray-bounds enablement. Here's what I've been saying on other patches (this one was different because it seemed to be just broken code): In preparation for FORTIFY_SOURCE performing compile-time and run-time field bounds checking for memcpy(), memmove(), and memset(), avoid intentionally writing across neighboring fields. Anyway, I can carry this until the full series is posted, but I'm still working through a few more fixes before I send the whole thing. This patch was one of a handful that didn't have any series dependencies. -Kees
diff --git a/drivers/media/platform/omap3isp/ispstat.c b/drivers/media/platform/omap3isp/ispstat.c index 5b9b57f4d9bf..ea8222fed38e 100644 --- a/drivers/media/platform/omap3isp/ispstat.c +++ b/drivers/media/platform/omap3isp/ispstat.c @@ -512,7 +512,7 @@ int omap3isp_stat_request_statistics(struct ispstat *stat, int omap3isp_stat_request_statistics_time32(struct ispstat *stat, struct omap3isp_stat_data_time32 *data) { - struct omap3isp_stat_data data64; + struct omap3isp_stat_data data64 = { }; int ret; ret = omap3isp_stat_request_statistics(stat, &data64); @@ -521,7 +521,8 @@ int omap3isp_stat_request_statistics_time32(struct ispstat *stat, data->ts.tv_sec = data64.ts.tv_sec; data->ts.tv_usec = data64.ts.tv_usec; - memcpy(&data->buf, &data64.buf, sizeof(*data) - sizeof(data->ts)); + data->buf = (uintptr_t)data64.buf; + memcpy(&data->frame, &data64.buf, sizeof(data->frame)); return 0; } diff --git a/include/uapi/linux/omap3isp.h b/include/uapi/linux/omap3isp.h index 87b55755f4ff..0a16af91621f 100644 --- a/include/uapi/linux/omap3isp.h +++ b/include/uapi/linux/omap3isp.h @@ -159,13 +159,25 @@ struct omap3isp_h3a_aewb_config { }; /** - * struct omap3isp_stat_data - Statistic data sent to or received from user - * @ts: Timestamp of returned framestats. - * @buf: Pointer to pass to user. + * struct omap3isp_stat_frame - Statistic data without timestamp nor pointer. + * @buf_size: Size of buffer. * @frame_number: Frame number of requested stats. * @cur_frame: Current frame number being processed. * @config_counter: Number of the configuration associated with the data. */ +struct omap3isp_stat_frame { + __u32 buf_size; + __u16 frame_number; + __u16 cur_frame; + __u16 config_counter; +}; + +/** + * struct omap3isp_stat_data - Statistic data sent to or received from user + * @ts: Timestamp of returned framestats. + * @buf: Pointer to pass to user. + * @frame: Statistic data for frame. + */ struct omap3isp_stat_data { #ifdef __KERNEL__ struct { @@ -176,10 +188,15 @@ struct omap3isp_stat_data { struct timeval ts; #endif void __user *buf; - __u32 buf_size; - __u16 frame_number; - __u16 cur_frame; - __u16 config_counter; + union { + struct { + __u32 buf_size; + __u16 frame_number; + __u16 cur_frame; + __u16 config_counter; + }; + struct omap3isp_stat_frame frame; + }; }; #ifdef __KERNEL__ @@ -189,10 +206,15 @@ struct omap3isp_stat_data_time32 { __s32 tv_usec; } ts; __u32 buf; - __u32 buf_size; - __u16 frame_number; - __u16 cur_frame; - __u16 config_counter; + union { + struct { + __u32 buf_size; + __u16 frame_number; + __u16 cur_frame; + __u16 config_counter; + }; + struct omap3isp_stat_frame frame; + }; }; #endif