mprutil: "fix user reply buffer (64)..." warnings

Depending on the card's firmware version, it may return different length
responses for MPI2_FUNCTION_IOC_FACTS.  But the first part of the
response contains the length of the rest, so query it first to get the
length and then use that to size the buffer for the full response.

Also, correctly zero-initialize MPI2_IOC_FACTS_REQUEST.  It only worked
by luck before.

PR:		264848
Reported by:	Julien Cigar <julien@perdition.city>
MFC after:	1 week
Sponsored by:	Axcient
Reviewed by:	scottl, imp
Differential Revision: https://reviews.freebsd.org/D38739

5 files changed, 33 insertions, 19 deletions

diff --git a/sys/dev/mpr/mpr.c b/sys/dev/mpr/mpr.c
index 72993be8834e..23f7ff0c3e9a 100644
--- a/sys/dev/mpr/mpr.c
+++ b/sys/dev/mpr/mpr.c
@@ -1871,7 +1871,7 @@ mpr_setup_sysctl(struct mpr_softc *sc)
 
 	SYSCTL_ADD_STRING(sysctl_ctx, SYSCTL_CHILDREN(sysctl_tree),
 	    OID_AUTO, "msg_version", CTLFLAG_RD, sc->msg_version,
-	    strlen(sc->msg_version), "message interface version");
+	    strlen(sc->msg_version), "message interface version (deprecated)");
 
 	SYSCTL_ADD_INT(sysctl_ctx, SYSCTL_CHILDREN(sysctl_tree),
 	    OID_AUTO, "io_cmds_active", CTLFLAG_RD,
diff --git a/sys/dev/mpr/mpr_user.c b/sys/dev/mpr/mpr_user.c
index d9dc3d2377a2..f2847ae36d66 100644
--- a/sys/dev/mpr/mpr_user.c
+++ b/sys/dev/mpr/mpr_user.c
@@ -852,7 +852,7 @@ mpr_user_pass_thru(struct mpr_softc *sc, mpr_pass_thru_t *data)
 			rpl = (MPI2_DEFAULT_REPLY *)cm->cm_reply;
 			sz = rpl->MsgLength * 4;
 
-			if (sz > data->ReplySize) {
+			if (bootverbose && sz > data->ReplySize) {
 				mpr_printf(sc, "%s: user reply buffer (%d) "
 				    "smaller than returned buffer (%d)\n",
 				    __func__, data->ReplySize, sz);
@@ -1077,7 +1077,7 @@ mpr_user_pass_thru(struct mpr_softc *sc, mpr_pass_thru_t *data)
 		rpl = (MPI2_DEFAULT_REPLY *)cm->cm_reply;
 		sz = rpl->MsgLength * 4;
 
-		if (sz > data->ReplySize) {
+		if (bootverbose && sz > data->ReplySize) {
 			mpr_printf(sc, "%s: user reply buffer (%d) smaller "
 			    "than returned buffer (%d)\n", __func__,
 			    data->ReplySize, sz);
diff --git a/sys/dev/mps/mps.c b/sys/dev/mps/mps.c
index 43362b96b7b6..f358ab8a73a9 100644
--- a/sys/dev/mps/mps.c
+++ b/sys/dev/mps/mps.c
@@ -1719,7 +1719,7 @@ mps_setup_sysctl(struct mps_softc *sc)
 
 	SYSCTL_ADD_STRING(sysctl_ctx, SYSCTL_CHILDREN(sysctl_tree),
 	    OID_AUTO, "msg_version", CTLFLAG_RD, sc->msg_version,
-	    strlen(sc->msg_version), "message interface version");
+	    strlen(sc->msg_version), "message interface version (deprecated)");
 
 	SYSCTL_ADD_INT(sysctl_ctx, SYSCTL_CHILDREN(sysctl_tree),
 	    OID_AUTO, "io_cmds_active", CTLFLAG_RD,
diff --git a/sys/dev/mps/mps_user.c b/sys/dev/mps/mps_user.c
index cf2fdb2b2adb..3d1b478d81b1 100644
--- a/sys/dev/mps/mps_user.c
+++ b/sys/dev/mps/mps_user.c
@@ -851,7 +851,7 @@ mps_user_pass_thru(struct mps_softc *sc, mps_pass_thru_t *data)
 			rpl = (MPI2_DEFAULT_REPLY *)cm->cm_reply;
 			sz = rpl->MsgLength * 4;
 
-			if (sz > data->ReplySize) {
+			if (bootverbose && sz > data->ReplySize) {
 				mps_printf(sc, "%s: user reply buffer (%d) "
 				    "smaller than returned buffer (%d)\n",
 				    __func__, data->ReplySize, sz);
@@ -1005,7 +1005,7 @@ mps_user_pass_thru(struct mps_softc *sc, mps_pass_thru_t *data)
 		rpl = (MPI2_DEFAULT_REPLY *)cm->cm_reply;
 		sz = rpl->MsgLength * 4;
 
-		if (sz > data->ReplySize) {
+		if (bootverbose && sz > data->ReplySize) {
 			mps_printf(sc, "%s: user reply buffer (%d) smaller "
 			    "than returned buffer (%d)\n", __func__,
 			    data->ReplySize, sz);
diff --git a/usr.sbin/mpsutil/mps_cmd.c b/usr.sbin/mpsutil/mps_cmd.c
index 448e4cea602f..2101bbba73b0 100644
--- a/usr.sbin/mpsutil/mps_cmd.c
+++ b/usr.sbin/mpsutil/mps_cmd.c
@@ -721,25 +721,39 @@ mps_pass_command(int fd, void *req, uint32_t req_len, void *reply,
 	return (0);
 }
 
+/* Return the length in bytes of the device's MPI2_IOC_FACTS reply */
+static size_t
+mps_get_ioc_factslen(int fd)
+{
+	MPI2_IOC_FACTS_REQUEST req;
+	const size_t factslen = 4;
+	char factsbuf[4] = {0};
+	MPI2_IOC_FACTS_REPLY *facts = (MPI2_IOC_FACTS_REPLY*)factsbuf;
+	int error;
+
+	bzero(&req, sizeof(req));
+	req.Function = MPI2_FUNCTION_IOC_FACTS;
+	error = mps_pass_command(fd, &req, sizeof(MPI2_IOC_FACTS_REQUEST),
+	    factsbuf, factslen, NULL, 0, NULL, 0, 10);
+
+	if (error)
+		return (0);
+
+	/* The card's response is measured in dwords */
+	return (facts->MsgLength * 4);
+}
+
 MPI2_IOC_FACTS_REPLY *
 mps_get_iocfacts(int fd)
 {
 	MPI2_IOC_FACTS_REPLY *facts;
 	MPI2_IOC_FACTS_REQUEST req;
-	char msgver[8], sysctlname[128];
-	size_t len, factslen;
+	size_t factslen;
 	int error;
 
-	snprintf(sysctlname, sizeof(sysctlname), "dev.%s.%d.msg_version",
-	    is_mps ? "mps" : "mpr", mps_unit);
-
-	factslen = sizeof(MPI2_IOC_FACTS_REPLY);
-	len = sizeof(msgver);
-	error = sysctlbyname(sysctlname, msgver, &len, NULL, 0);
-	if (error == 0) {
-		if (strncmp(msgver, "2.6", sizeof(msgver)) == 0)
-			factslen += 4;
-	}
+	factslen = mps_get_ioc_factslen(fd);
+	if (factslen == 0)
+		return (NULL);
 
 	facts = malloc(factslen);
 	if (facts == NULL) {
@@ -747,7 +761,7 @@ mps_get_iocfacts(int fd)
 		return (NULL);
 	}
 
-	bzero(&req, factslen);
+	bzero(&req, sizeof(req));
 	req.Function = MPI2_FUNCTION_IOC_FACTS;
 
 #if 1