LKML Archive on lore.kernel.org
help / color / mirror / Atom feed
From: Kees Cook <keescook@chromium.org>
To: linux-kernel@vger.kernel.org
Cc: Kees Cook <keescook@chromium.org>,
	Marc Kleine-Budde <mkl@pengutronix.de>,
	Rasmus Villemoes <linux@rasmusvillemoes.dk>,
	Daniel Micay <danielmicay@gmail.com>,
	Francis Laniel <laniel_francis@privacyrequired.com>,
	Bart Van Assche <bvanassche@acm.org>,
	David Gow <davidgow@google.com>,
	linux-mm@kvack.org, clang-built-linux@googlegroups.com,
	linux-hardening@vger.kernel.org
Subject: [PATCH for-next 11/25] can: flexcan: Use struct_group() to zero struct flexcan_regs regions
Date: Sun, 22 Aug 2021 00:51:08 -0700	[thread overview]
Message-ID: <20210822075122.864511-12-keescook@chromium.org> (raw)
In-Reply-To: <20210822075122.864511-1-keescook@chromium.org>

In preparation for FORTIFY_SOURCE performing compile-time and run-time
field bounds checking for memset(), avoid intentionally writing across
neighboring fields.

Add struct_group() to mark both regions of struct flexcan_regs that get
initialized to zero. Avoid the future warnings:

In function 'fortify_memset_chk',
    inlined from 'memset_io' at ./include/asm-generic/io.h:1169:2,
    inlined from 'flexcan_ram_init' at drivers/net/can/flexcan.c:1403:2:
./include/linux/fortify-string.h:199:4: warning: call to '__write_overflow_field' declared with attribute warning: detected write beyond size of field (1st parameter); maybe use struct_group()? [-Wattribute-warning]
  199 |    __write_overflow_field(p_size_field, size);
      |    ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
In function 'fortify_memset_chk',
    inlined from 'memset_io' at ./include/asm-generic/io.h:1169:2,
    inlined from 'flexcan_ram_init' at drivers/net/can/flexcan.c:1408:3:
./include/linux/fortify-string.h:199:4: warning: call to '__write_overflow_field' declared with attribute warning: detected write beyond size of field (1st parameter); maybe use struct_group()? [-Wattribute-warning]
  199 |    __write_overflow_field(p_size_field, size);
      |    ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Acked-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Kees Cook <keescook@chromium.org>
---
 drivers/net/can/flexcan.c | 68 +++++++++++++++++++--------------------
 1 file changed, 34 insertions(+), 34 deletions(-)

diff --git a/drivers/net/can/flexcan.c b/drivers/net/can/flexcan.c
index 57f3635ad8d7..b1a261622b76 100644
--- a/drivers/net/can/flexcan.c
+++ b/drivers/net/can/flexcan.c
@@ -284,31 +284,33 @@ struct flexcan_regs {
 	u32 dbg1;		/* 0x58 */
 	u32 dbg2;		/* 0x5c */
 	u32 _reserved3[8];	/* 0x60 */
-	u8 mb[2][512];		/* 0x80 - Not affected by Soft Reset */
-	/* FIFO-mode:
-	 *			MB
-	 * 0x080...0x08f	0	RX message buffer
-	 * 0x090...0x0df	1-5	reserved
-	 * 0x0e0...0x0ff	6-7	8 entry ID table
-	 *				(mx25, mx28, mx35, mx53)
-	 * 0x0e0...0x2df	6-7..37	8..128 entry ID table
-	 *				size conf'ed via ctrl2::RFFN
-	 *				(mx6, vf610)
-	 */
-	u32 _reserved4[256];	/* 0x480 */
-	u32 rximr[64];		/* 0x880 - Not affected by Soft Reset */
-	u32 _reserved5[24];	/* 0x980 */
-	u32 gfwr_mx6;		/* 0x9e0 - MX6 */
-	u32 _reserved6[39];	/* 0x9e4 */
-	u32 _rxfir[6];		/* 0xa80 */
-	u32 _reserved8[2];	/* 0xa98 */
-	u32 _rxmgmask;		/* 0xaa0 */
-	u32 _rxfgmask;		/* 0xaa4 */
-	u32 _rx14mask;		/* 0xaa8 */
-	u32 _rx15mask;		/* 0xaac */
-	u32 tx_smb[4];		/* 0xab0 */
-	u32 rx_smb0[4];		/* 0xac0 */
-	u32 rx_smb1[4];		/* 0xad0 */
+	struct_group(init,
+		u8 mb[2][512];		/* 0x80 - Not affected by Soft Reset */
+		/* FIFO-mode:
+		 *			MB
+		 * 0x080...0x08f	0	RX message buffer
+		 * 0x090...0x0df	1-5	reserved
+		 * 0x0e0...0x0ff	6-7	8 entry ID table
+		 *				(mx25, mx28, mx35, mx53)
+		 * 0x0e0...0x2df	6-7..37	8..128 entry ID table
+		 *				size conf'ed via ctrl2::RFFN
+		 *				(mx6, vf610)
+		 */
+		u32 _reserved4[256];	/* 0x480 */
+		u32 rximr[64];		/* 0x880 - Not affected by Soft Reset */
+		u32 _reserved5[24];	/* 0x980 */
+		u32 gfwr_mx6;		/* 0x9e0 - MX6 */
+		u32 _reserved6[39];	/* 0x9e4 */
+		u32 _rxfir[6];		/* 0xa80 */
+		u32 _reserved8[2];	/* 0xa98 */
+		u32 _rxmgmask;		/* 0xaa0 */
+		u32 _rxfgmask;		/* 0xaa4 */
+		u32 _rx14mask;		/* 0xaa8 */
+		u32 _rx15mask;		/* 0xaac */
+		u32 tx_smb[4];		/* 0xab0 */
+		u32 rx_smb0[4];		/* 0xac0 */
+		u32 rx_smb1[4];		/* 0xad0 */
+	);
 	u32 mecr;		/* 0xae0 */
 	u32 erriar;		/* 0xae4 */
 	u32 erridpr;		/* 0xae8 */
@@ -322,9 +324,11 @@ struct flexcan_regs {
 	u32 fdcbt;		/* 0xc04 - Not affected by Soft Reset */
 	u32 fdcrc;		/* 0xc08 */
 	u32 _reserved9[199];	/* 0xc0c */
-	u32 tx_smb_fd[18];	/* 0xf28 */
-	u32 rx_smb0_fd[18];	/* 0xf70 */
-	u32 rx_smb1_fd[18];	/* 0xfb8 */
+	struct_group(init_fd,
+		u32 tx_smb_fd[18];	/* 0xf28 */
+		u32 rx_smb0_fd[18];	/* 0xf70 */
+		u32 rx_smb1_fd[18];	/* 0xfb8 */
+	);
 };
 
 static_assert(sizeof(struct flexcan_regs) ==  0x4 * 18 + 0xfb8);
@@ -1379,14 +1383,10 @@ static void flexcan_ram_init(struct net_device *dev)
 	reg_ctrl2 |= FLEXCAN_CTRL2_WRMFRZ;
 	priv->write(reg_ctrl2, &regs->ctrl2);
 
-	memset_io(&regs->mb[0][0], 0,
-		  offsetof(struct flexcan_regs, rx_smb1[3]) -
-		  offsetof(struct flexcan_regs, mb[0][0]) + 0x4);
+	memset_io(&regs->init, 0, sizeof(regs->init));
 
 	if (priv->can.ctrlmode & CAN_CTRLMODE_FD)
-		memset_io(&regs->tx_smb_fd[0], 0,
-			  offsetof(struct flexcan_regs, rx_smb1_fd[17]) -
-			  offsetof(struct flexcan_regs, tx_smb_fd[0]) + 0x4);
+		memset_io(&regs->init_fd, 0, sizeof(regs->init_fd));
 
 	reg_ctrl2 &= ~FLEXCAN_CTRL2_WRMFRZ;
 	priv->write(reg_ctrl2, &regs->ctrl2);
-- 
2.30.2


  parent reply	other threads:[~2021-08-22  7:53 UTC|newest]

Thread overview: 42+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-08-22  7:50 [PATCH for-next 00/25] Prepare for better FORTIFY_SOURCE Kees Cook
2021-08-22  7:50 ` [PATCH for-next 01/25] scsi: ibmvscsi: Avoid multi-field memset() overflow by aiming at srp Kees Cook
2021-08-22  7:50 ` [PATCH for-next 02/25] powerpc: Split memset() to avoid multi-field overflow Kees Cook
2021-08-22  7:51 ` [PATCH for-next 03/25] stddef: Fix kerndoc for sizeof_field() and offsetofend() Kees Cook
2021-08-22  7:51 ` [PATCH for-next 04/25] stddef: Introduce struct_group() helper macro Kees Cook
2021-08-22  7:51 ` [PATCH for-next 05/25] cxl/core: Replace unions with struct_group() Kees Cook
2021-08-22  7:51 ` [PATCH for-next 06/25] bnxt_en: Use struct_group_attr() for memcpy() region Kees Cook
2021-08-22  7:51 ` [PATCH for-next 07/25] iommu/amd: Use struct_group() " Kees Cook
2021-08-22  7:51 ` [PATCH for-next 08/25] drm/mga/mga_ioc32: " Kees Cook
2021-08-22  7:51 ` [PATCH for-next 09/25] HID: cp2112: " Kees Cook
2021-08-22  7:51 ` [PATCH for-next 10/25] HID: roccat: Use struct_group() to zero kone_mouse_event Kees Cook
2021-08-22  7:51 ` Kees Cook [this message]
2021-08-22  7:51 ` [PATCH for-next 12/25] cm4000_cs: Use struct_group() to zero struct cm4000_dev region Kees Cook
2021-08-22  7:51 ` [PATCH for-next 13/25] compiler_types.h: Remove __compiletime_object_size() Kees Cook
2021-08-23  6:43   ` Rasmus Villemoes
2021-08-25 19:43     ` Nick Desaulniers
2021-08-22  7:51 ` [PATCH for-next 14/25] lib/string: Move helper functions out of string.c Kees Cook
2021-08-25 21:48   ` Nick Desaulniers
2021-08-26  2:47     ` Kees Cook
2021-08-26 18:08       ` Nick Desaulniers
2021-08-22  7:51 ` [PATCH for-next 15/25] fortify: Move remaining fortify helpers into fortify-string.h Kees Cook
2021-08-25 21:59   ` Nick Desaulniers
2021-08-22  7:51 ` [PATCH for-next 16/25] fortify: Explicitly disable Clang support Kees Cook
2021-08-25 19:41   ` Nick Desaulniers
2021-08-22  7:51 ` [PATCH for-next 17/25] fortify: Fix dropped strcpy() compile-time write overflow check Kees Cook
2021-08-25 21:55   ` Nick Desaulniers
2021-08-22  7:51 ` [PATCH for-next 18/25] fortify: Prepare to improve strnlen() and strlen() warnings Kees Cook
2021-08-25 22:01   ` Nick Desaulniers
2021-08-22  7:51 ` [PATCH for-next 19/25] fortify: Allow strlen() and strnlen() to pass compile-time known lengths Kees Cook
2021-08-25 22:05   ` Nick Desaulniers
2021-08-26  2:56     ` Kees Cook
2021-08-26 18:02       ` Nick Desaulniers
2021-08-22  7:51 ` [PATCH for-next 20/25] fortify: Add compile-time FORTIFY_SOURCE tests Kees Cook
2021-08-22  7:51 ` [PATCH for-next 21/25] lib: Introduce CONFIG_TEST_MEMCPY Kees Cook
2021-08-24  7:00   ` David Gow
2021-08-25  2:32     ` Kees Cook
2021-10-18 15:46   ` Arnd Bergmann
2021-10-18 19:28     ` Kees Cook
2021-08-22  7:51 ` [PATCH for-next 22/25] string.h: Introduce memset_after() for wiping trailing members/padding Kees Cook
2021-08-22  7:51 ` [PATCH for-next 23/25] xfrm: Use memset_after() to clear padding Kees Cook
2021-08-22  7:51 ` [PATCH for-next 24/25] string.h: Introduce memset_startat() for wiping trailing members and padding Kees Cook
2021-08-22  7:51 ` [PATCH for-next 25/25] btrfs: Use memset_startat() to clear end of struct 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=20210822075122.864511-12-keescook@chromium.org \
    --to=keescook@chromium.org \
    --cc=bvanassche@acm.org \
    --cc=clang-built-linux@googlegroups.com \
    --cc=danielmicay@gmail.com \
    --cc=davidgow@google.com \
    --cc=laniel_francis@privacyrequired.com \
    --cc=linux-hardening@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=linux@rasmusvillemoes.dk \
    --cc=mkl@pengutronix.de \
    --subject='Re: [PATCH for-next 11/25] can: flexcan: Use struct_group() to zero struct flexcan_regs regions' \
    /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

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).