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>
Sponsored by:	Axcient
Reviewed by:	scottl, imp
Differential Revision: https://reviews.freebsd.org/D38739

(cherry picked from commit 7d154c4dc64e61af7ca536c4e9927fa07c675a83)

5 files changed, 33 insertions, 19 deletions

diff --git a/sys/dev/mpr/mpr.c b/sys/dev/mpr/mpr.c
index 6d41b77b1182..161914748e56 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 a312e95df771..10aea28db9ee 100644
--- a/sys/dev/mps/mps.c
+++ b/sys/dev/mps/mps.c
@@ -1716,7 +1716,7 @@ 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 a1ee620c713a..49dc0f05619c 100644
--- a/sys/dev/mps/mps_user.c
+++ b/sys/dev/mps/mps_user.c
@@ -863,7 +863,7 @@ 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);
@@ -1017,7 +1017,7 @@ 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