[PATCH 15/17] scsi: lpfc: Use struct_group() to initialize struct lpfc_cgn_info

Kees Cook
2021-12-13T22:39:09Z

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 "stat" region of struct lpfc_cgn_info that
should be initialized to zero, and refactor the "data" region memset()
to wipe everything up to the cgn_stats region.

Cc: James Smart <james.smart@broadcom.com>
Cc: Dick Kennedy <dick.kennedy@broadcom.com>
Cc: "James E.J. Bottomley" <jejb@linux.ibm.com>
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>
Cc: linux-scsi@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
---
drivers/scsi/lpfc/lpfc.h | 90 +++++++++++++++++------------------
drivers/scsi/lpfc/lpfc_init.c | 4 +-
2 files changed, 46 insertions(+), 48 deletions(-)

diff --git a/drivers/scsi/lpfc/lpfc.h b/drivers/scsi/lpfc/lpfc.h
index 3faadcfcdcbb..4878c94761f9 100644
--- a/drivers/scsi/lpfc/lpfc.h
+++ b/drivers/scsi/lpfc/lpfc.h
@@ -496,52 +496,50 @@ struct lpfc_cgn_info {
__le32 cgn_alarm_hr[24];
__le32 cgn_alarm_day[LPFC_MAX_CGN_DAYS];

- /* Start of congestion statistics */
- uint8_t cgn_stat_npm; /* Notifications per minute */
-
- /* Start Time */
- uint8_t cgn_stat_month;
- uint8_t cgn_stat_day;
- uint8_t cgn_stat_year;
- uint8_t cgn_stat_hour;
- uint8_t cgn_stat_minute;
- uint8_t cgn_pad2[2];
-
- __le32 cgn_notification;
- __le32 cgn_peer_notification;
- __le32 link_integ_notification;
- __le32 delivery_notification;
-
- uint8_t cgn_stat_cgn_month; /* Last congestion notification FPIN */
- uint8_t cgn_stat_cgn_day;
- uint8_t cgn_stat_cgn_year;
- uint8_t cgn_stat_cgn_hour;
- uint8_t cgn_stat_cgn_min;
- uint8_t cgn_stat_cgn_sec;
-
- uint8_t cgn_stat_peer_month; /* Last peer congestion FPIN */
- uint8_t cgn_stat_peer_day;
- uint8_t cgn_stat_peer_year;
- uint8_t cgn_stat_peer_hour;
- uint8_t cgn_stat_peer_min;
- uint8_t cgn_stat_peer_sec;
-
- uint8_t cgn_stat_lnk_month; /* Last link integrity FPIN */
- uint8_t cgn_stat_lnk_day;
- uint8_t cgn_stat_lnk_year;
- uint8_t cgn_stat_lnk_hour;
- uint8_t cgn_stat_lnk_min;
- uint8_t cgn_stat_lnk_sec;
-
- uint8_t cgn_stat_del_month; /* Last delivery notification FPIN */
- uint8_t cgn_stat_del_day;
- uint8_t cgn_stat_del_year;
- uint8_t cgn_stat_del_hour;
- uint8_t cgn_stat_del_min;
- uint8_t cgn_stat_del_sec;
-#define LPFC_CGN_STAT_SIZE 48
-#define LPFC_CGN_DATA_SIZE (sizeof(struct lpfc_cgn_info) - \
- LPFC_CGN_STAT_SIZE - sizeof(uint32_t))
+ struct_group(cgn_stat,
+ uint8_t cgn_stat_npm; /* Notifications per minute */
+
+ /* Start Time */
+ uint8_t cgn_stat_month;
+ uint8_t cgn_stat_day;
+ uint8_t cgn_stat_year;
+ uint8_t cgn_stat_hour;
+ uint8_t cgn_stat_minute;
+ uint8_t cgn_pad2[2];
+
+ __le32 cgn_notification;
+ __le32 cgn_peer_notification;
+ __le32 link_integ_notification;
+ __le32 delivery_notification;
+
+ uint8_t cgn_stat_cgn_month; /* Last congestion notification FPIN */
+ uint8_t cgn_stat_cgn_day;
+ uint8_t cgn_stat_cgn_year;
+ uint8_t cgn_stat_cgn_hour;
+ uint8_t cgn_stat_cgn_min;
+ uint8_t cgn_stat_cgn_sec;
+
+ uint8_t cgn_stat_peer_month; /* Last peer congestion FPIN */
+ uint8_t cgn_stat_peer_day;
+ uint8_t cgn_stat_peer_year;
+ uint8_t cgn_stat_peer_hour;
+ uint8_t cgn_stat_peer_min;
+ uint8_t cgn_stat_peer_sec;
+
+ uint8_t cgn_stat_lnk_month; /* Last link integrity FPIN */
+ uint8_t cgn_stat_lnk_day;
+ uint8_t cgn_stat_lnk_year;
+ uint8_t cgn_stat_lnk_hour;
+ uint8_t cgn_stat_lnk_min;
+ uint8_t cgn_stat_lnk_sec;
+
+ uint8_t cgn_stat_del_month; /* Last delivery notification FPIN */
+ uint8_t cgn_stat_del_day;
+ uint8_t cgn_stat_del_year;
+ uint8_t cgn_stat_del_hour;
+ uint8_t cgn_stat_del_min;
+ uint8_t cgn_stat_del_sec;
+ );

__le32 cgn_info_crc;
#define LPFC_CGN_CRC32_MAGIC_NUMBER 0x1EDC6F41
diff --git a/drivers/scsi/lpfc/lpfc_init.c b/drivers/scsi/lpfc/lpfc_init.c
index 2fe7d9d885d9..c18000d05379 100644
--- a/drivers/scsi/lpfc/lpfc_init.c
+++ b/drivers/scsi/lpfc/lpfc_init.c
@@ -13483,7 +13483,7 @@ lpfc_init_congestion_buf(struct lpfc_hba *phba)
phba->cgn_evt_minute = 0;
phba->hba_flag &= ~HBA_CGN_DAY_WRAP;

- memset(cp, 0xff, LPFC_CGN_DATA_SIZE);
+ memset(cp, 0xff, offsetof(struct lpfc_cgn_info, cgn_stat));
cp->cgn_info_size = cpu_to_le16(LPFC_CGN_INFO_SZ);
cp->cgn_info_version = LPFC_CGN_INFO_V3;

@@ -13542,7 +13542,7 @@ lpfc_init_congestion_stat(struct lpfc_hba *phba)
return;

cp = (struct lpfc_cgn_info *)phba->cgn_i->virt;
- memset(&cp->cgn_stat_npm, 0, LPFC_CGN_STAT_SIZE);
+ memset(&cp->cgn_stat, 0, sizeof(cp->cgn_stat));

ktime_get_real_ts64(&cmpl_time);
time64_to_tm(cmpl_time.tv_sec, 0, &broken);
--
2.30.2