[PATCH][next] scsi: Replace one-element arrays with flexible-array members

From: Gustavo A. R. Silva
Date: Fri Nov 05 2021 - 05:06:29 EST


Use flexible-array members in struct fc_fdmi_attr_entry and
fs_fdmi_attrs instead of one-element arrays, and refactor the
code accordingly.

Also, turn the one-element array _port_ in struct fc_fdmi_rpl
into a simple object of type struct fc_fdmi_port_name, as it
seems there is no more than just one port expected:

$ git grep -nw numport drivers/scsi/
drivers/scsi/csiostor/csio_lnode.c:447: reg_pl->numport = htonl(1);
drivers/scsi/libfc/fc_encode.h:232: put_unaligned_be32(1, &ct->payload.rhba.port.numport);

Also, this helps with the ongoing efforts to globally enable
-Warray-bounds and get us closer to being able to tighten the
FORTIFY_SOURCE routines on memcpy().

https://github.com/KSPP/linux/issues/79
Signed-off-by: Gustavo A. R. Silva <gustavoars@xxxxxxxxxx>
---
drivers/scsi/csiostor/csio_lnode.c | 2 +-
drivers/scsi/libfc/fc_encode.h | 4 ++--
include/scsi/fc/fc_ms.h | 6 +++---
3 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/drivers/scsi/csiostor/csio_lnode.c b/drivers/scsi/csiostor/csio_lnode.c
index d5ac93897023..cf9dd79ee488 100644
--- a/drivers/scsi/csiostor/csio_lnode.c
+++ b/drivers/scsi/csiostor/csio_lnode.c
@@ -445,7 +445,7 @@ csio_ln_fdmi_dprt_cbfn(struct csio_hw *hw, struct csio_ioreq *fdmi_req)
/* Register one port per hba */
reg_pl = (struct fc_fdmi_rpl *)pld;
reg_pl->numport = htonl(1);
- memcpy(&reg_pl->port[0].portname, csio_ln_wwpn(ln), 8);
+ memcpy(&reg_pl->port.portname, csio_ln_wwpn(ln), 8);
pld += sizeof(*reg_pl);

/* Start appending HBA attributes hba */
diff --git a/drivers/scsi/libfc/fc_encode.h b/drivers/scsi/libfc/fc_encode.h
index 74ae7fd15d8d..5806f99e4061 100644
--- a/drivers/scsi/libfc/fc_encode.h
+++ b/drivers/scsi/libfc/fc_encode.h
@@ -232,7 +232,7 @@ static inline int fc_ct_ms_fill(struct fc_lport *lport,
put_unaligned_be32(1, &ct->payload.rhba.port.numport);
/* Port Name */
put_unaligned_be64(lport->wwpn,
- &ct->payload.rhba.port.port[0].portname);
+ &ct->payload.rhba.port.port.portname);

/* HBA Attributes */
put_unaligned_be32(numattrs,
@@ -246,7 +246,7 @@ static inline int fc_ct_ms_fill(struct fc_lport *lport,
&entry->type);
put_unaligned_be16(len, &entry->len);
put_unaligned_be64(lport->wwnn,
- (__be64 *)&entry->value[0]);
+ (__be64 *)&entry->value);

/* Manufacturer */
entry = (struct fc_fdmi_attr_entry *)((char *)entry->value +
diff --git a/include/scsi/fc/fc_ms.h b/include/scsi/fc/fc_ms.h
index 00191695233a..44fbe84fa664 100644
--- a/include/scsi/fc/fc_ms.h
+++ b/include/scsi/fc/fc_ms.h
@@ -158,7 +158,7 @@ struct fc_fdmi_port_name {
struct fc_fdmi_attr_entry {
__be16 type;
__be16 len;
- __u8 value[1];
+ __u8 value[];
} __attribute__((__packed__));

/*
@@ -166,7 +166,7 @@ struct fc_fdmi_attr_entry {
*/
struct fs_fdmi_attrs {
__be32 numattrs;
- struct fc_fdmi_attr_entry attr[1];
+ struct fc_fdmi_attr_entry attr[];
} __attribute__((__packed__));

/*
@@ -174,7 +174,7 @@ struct fs_fdmi_attrs {
*/
struct fc_fdmi_rpl {
__be32 numport;
- struct fc_fdmi_port_name port[1];
+ struct fc_fdmi_port_name port;
} __attribute__((__packed__));

/*
--
2.27.0