diff mbox series

bnx2x: Use struct_group() for memcpy() region

Message ID 20211118184253.1284535-1-keescook@chromium.org (mailing list archive)
State Accepted
Commit 29fd0ec65e912613945c2d9fe7d551a842a26b0d
Delegated to: Netdev Maintainers
Headers show
Series bnx2x: Use struct_group() for memcpy() region | expand

Checks

Context Check Description
netdev/fixes_present success Fixes tag not required for -next series
netdev/subject_prefix warning Target tree name not specified in the subject
netdev/cover_letter success Single patches do not need cover letters
netdev/patch_count success Link
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 101 this patch: 101
netdev/cc_maintainers warning 1 maintainers not CCed: manishc@marvell.com
netdev/build_clang success Errors and warnings before: 6 this patch: 6
netdev/module_param success Was 0 now: 0
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 101 this patch: 101
netdev/checkpatch warning CHECK: Alignment should match open parenthesis CHECK: Unnecessary parentheses around bp->port.old_nig_stats.egress_mac_pkt0 CHECK: Unnecessary parentheses around bp->port.old_nig_stats.egress_mac_pkt1 CHECK: Unnecessary parentheses around estats->shared CHECK: Unnecessary parentheses around pstats->mac_stx[1]
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0
netdev/tree_selection success Guessing tree name failed - patch did not apply

Commit Message

Kees Cook Nov. 18, 2021, 6:42 p.m. UTC 
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.

Use struct_group() in struct nig_stats around members egress_mac_pkt0_lo,
egress_mac_pkt0_hi, egress_mac_pkt1_lo, and egress_mac_pkt1_hi (and the
respective members in struct bnx2x_eth_stats), so they can be referenced
together. This will allow memcpy() and sizeof() to more easily reason
about sizes, improve readability, and avoid future warnings about writing
beyond the end of struct bnx2x_eth_stats's rx_stat_ifhcinbadoctets_hi.

"pahole" shows no size nor member offset changes to either struct.
"objdump -d" shows no meaningful object code changes (i.e. only source
line number induced differences and optimizations).

Additionally adds BUILD_BUG_ON() to compare the separate struct group
sizes.

Reviewed-by: Prabhakar Kushwaha <pkushwaha@marvell.com>
Link: https://lore.kernel.org/lkml/DM5PR18MB2229B0413C372CC6E49D59A3B2C59@DM5PR18MB2229.namprd18.prod.outlook.com
Signed-off-by: Kees Cook <keescook@chromium.org>
---
 drivers/net/ethernet/broadcom/bnx2x/bnx2x_stats.c |  7 ++++---
 drivers/net/ethernet/broadcom/bnx2x/bnx2x_stats.h | 14 ++++++++++----
 2 files changed, 14 insertions(+), 7 deletions(-)

Comments

patchwork-bot+netdevbpf@kernel.org Nov. 19, 2021, 11:50 a.m. UTC | #1 
Hello:

This patch was applied to netdev/net-next.git (master)
by David S. Miller <davem@davemloft.net>:

On Thu, 18 Nov 2021 10:42:53 -0800 you wrote:
> 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.
> 
> Use struct_group() in struct nig_stats around members egress_mac_pkt0_lo,
> egress_mac_pkt0_hi, egress_mac_pkt1_lo, and egress_mac_pkt1_hi (and the
> respective members in struct bnx2x_eth_stats), so they can be referenced
> together. This will allow memcpy() and sizeof() to more easily reason
> about sizes, improve readability, and avoid future warnings about writing
> beyond the end of struct bnx2x_eth_stats's rx_stat_ifhcinbadoctets_hi.
> 
> [...]

Here is the summary with links:
  - bnx2x: Use struct_group() for memcpy() region
    https://git.kernel.org/netdev/net-next/c/29fd0ec65e91

You are awesome, thank you!
diff mbox series

Patch

diff --git a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_stats.c b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_stats.c
index 0b193edb73b8..2bb133ae61c3 100644
--- a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_stats.c
+++ b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_stats.c
@@ -849,7 +849,8 @@  static int bnx2x_hw_stats_update(struct bnx2x *bp)
 
 	memcpy(old, new, sizeof(struct nig_stats));
 
-	memcpy(&(estats->rx_stat_ifhcinbadoctets_hi), &(pstats->mac_stx[1]),
+	BUILD_BUG_ON(sizeof(estats->shared) != sizeof(pstats->mac_stx[1]));
+	memcpy(&(estats->shared), &(pstats->mac_stx[1]),
 	       sizeof(struct mac_stx));
 	estats->brb_drop_hi = pstats->brb_drop_hi;
 	estats->brb_drop_lo = pstats->brb_drop_lo;
@@ -1634,9 +1635,9 @@  void bnx2x_stats_init(struct bnx2x *bp)
 			REG_RD(bp, NIG_REG_STAT0_BRB_TRUNCATE + port*0x38);
 	if (!CHIP_IS_E3(bp)) {
 		REG_RD_DMAE(bp, NIG_REG_STAT0_EGRESS_MAC_PKT0 + port*0x50,
-			    &(bp->port.old_nig_stats.egress_mac_pkt0_lo), 2);
+			    &(bp->port.old_nig_stats.egress_mac_pkt0), 2);
 		REG_RD_DMAE(bp, NIG_REG_STAT0_EGRESS_MAC_PKT1 + port*0x50,
-			    &(bp->port.old_nig_stats.egress_mac_pkt1_lo), 2);
+			    &(bp->port.old_nig_stats.egress_mac_pkt1), 2);
 	}
 
 	/* Prepare statistics ramrod data */
diff --git a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_stats.h b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_stats.h
index d55e63692cf3..ae93c078707b 100644
--- a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_stats.h
+++ b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_stats.h
@@ -36,10 +36,14 @@  struct nig_stats {
 	u32 pbf_octets;
 	u32 pbf_packet;
 	u32 safc_inp;
-	u32 egress_mac_pkt0_lo;
-	u32 egress_mac_pkt0_hi;
-	u32 egress_mac_pkt1_lo;
-	u32 egress_mac_pkt1_hi;
+	struct_group(egress_mac_pkt0,
+		u32 egress_mac_pkt0_lo;
+		u32 egress_mac_pkt0_hi;
+	);
+	struct_group(egress_mac_pkt1,
+		u32 egress_mac_pkt1_lo;
+		u32 egress_mac_pkt1_hi;
+	);
 };
 
 enum bnx2x_stats_event {
@@ -83,6 +87,7 @@  struct bnx2x_eth_stats {
 	u32 no_buff_discard_hi;
 	u32 no_buff_discard_lo;
 
+	struct_group(shared,
 	u32 rx_stat_ifhcinbadoctets_hi;
 	u32 rx_stat_ifhcinbadoctets_lo;
 	u32 tx_stat_ifhcoutbadoctets_hi;
@@ -159,6 +164,7 @@  struct bnx2x_eth_stats {
 	u32 tx_stat_dot3statsinternalmactransmiterrors_lo;
 	u32 tx_stat_bmac_ufl_hi;
 	u32 tx_stat_bmac_ufl_lo;
+	);
 
 	u32 pause_frames_received_hi;
 	u32 pause_frames_received_lo;