diff --git a/sys/dev/sfxge/common/ef10_rx.c b/sys/dev/sfxge/common/ef10_rx.c
index c237a9aeda14..e46fae0b95c5 100644
--- a/sys/dev/sfxge/common/ef10_rx.c
+++ b/sys/dev/sfxge/common/ef10_rx.c
@@ -64,6 +64,11 @@ efx_mcdi_init_rxq(
 
 	EFSYS_ASSERT3U(ndescs, <=, EFX_RXQ_MAXNDESCS);
 
+	if ((esmp == NULL) || (EFSYS_MEM_SIZE(esmp) < EFX_RXQ_SIZE(ndescs))) {
+		rc = EINVAL;
+		goto fail1;
+	}
+
 	if (ps_bufsize > 0)
 		dma_mode = MC_CMD_INIT_RXQ_EXT_IN_PACKED_STREAM;
 	else
@@ -130,11 +135,13 @@ efx_mcdi_init_rxq(
 
 	if (req.emr_rc != 0) {
 		rc = req.emr_rc;
-		goto fail1;
+		goto fail2;
 	}
 
 	return (0);
 
+fail2:
+	EFSYS_PROBE(fail2);
 fail1:
 	EFSYS_PROBE1(fail1, efx_rc_t, rc);
 
diff --git a/sys/dev/sfxge/common/ef10_tx.c b/sys/dev/sfxge/common/ef10_tx.c
index 36e577c81f1a..b37a0c8d7efa 100644
--- a/sys/dev/sfxge/common/ef10_tx.c
+++ b/sys/dev/sfxge/common/ef10_tx.c
@@ -69,10 +69,15 @@ efx_mcdi_init_txq(
 	EFSYS_ASSERT(EFX_TXQ_MAX_BUFS >=
 	    EFX_TXQ_NBUFS(enp->en_nic_cfg.enc_txq_max_ndescs));
 
+	if ((esmp == NULL) || (EFSYS_MEM_SIZE(esmp) < EFX_TXQ_SIZE(ndescs))) {
+		rc = EINVAL;
+		goto fail1;
+	}
+
 	npages = EFX_TXQ_NBUFS(ndescs);
 	if (MC_CMD_INIT_TXQ_IN_LEN(npages) > sizeof (payload)) {
 		rc = EINVAL;
-		goto fail1;
+		goto fail2;
 	}
 
 	(void) memset(payload, 0, sizeof (payload));
@@ -121,11 +126,13 @@ efx_mcdi_init_txq(
 
 	if (req.emr_rc != 0) {
 		rc = req.emr_rc;
-		goto fail2;
+		goto fail3;
 	}
 
 	return (0);
 
+fail3:
+	EFSYS_PROBE(fail3);
 fail2:
 	EFSYS_PROBE(fail2);
 fail1:
diff --git a/sys/dev/sfxge/common/efsys.h b/sys/dev/sfxge/common/efsys.h
index 7874f2b81cc0..d6d59af04224 100644
--- a/sys/dev/sfxge/common/efsys.h
+++ b/sys/dev/sfxge/common/efsys.h
@@ -392,8 +392,18 @@ typedef struct efsys_mem_s {
 	bus_dmamap_t		esm_map;
 	caddr_t			esm_base;
 	efsys_dma_addr_t	esm_addr;
+	size_t			esm_size;
 } efsys_mem_t;
 
+#define	EFSYS_MEM_SIZE(_esmp)						\
+	((_esmp)->esm_size)
+
+#define	EFSYS_MEM_ADDR(_esmp)						\
+	((_esmp)->esm_addr)
+
+#define	EFSYS_MEM_IS_NULL(_esmp)					\
+	((_esmp)->esm_base == NULL)
+
 
 #define	EFSYS_MEM_ZERO(_esmp, _size)					\
 	do {								\
@@ -617,12 +627,6 @@ typedef struct efsys_mem_s {
 	} while (B_FALSE)
 #endif
 
-#define	EFSYS_MEM_ADDR(_esmp)						\
-	((_esmp)->esm_addr)
-
-#define	EFSYS_MEM_IS_NULL(_esmp)					\
-	((_esmp)->esm_base == NULL)
-
 /* BAR */
 
 #define	SFXGE_LOCK_NAME_MAX	16
diff --git a/sys/dev/sfxge/common/efx_intr.c b/sys/dev/sfxge/common/efx_intr.c
index 911679656d13..279413807e7c 100644
--- a/sys/dev/sfxge/common/efx_intr.c
+++ b/sys/dev/sfxge/common/efx_intr.c
@@ -318,6 +318,12 @@ siena_intr_init(
 {
 	efx_intr_t *eip = &(enp->en_intr);
 	efx_oword_t oword;
+	efx_rc_t rc;
+
+	if ((esmp == NULL) || (EFSYS_MEM_SIZE(esmp) < EFX_INTR_SIZE)) {
+		rc = EINVAL;
+		goto fail1;
+	}
 
 	/*
 	 * bug17213 workaround.
@@ -349,6 +355,11 @@ siena_intr_init(
 	EFX_BAR_WRITEO(enp, FR_AZ_INT_ADR_REG_KER, &oword);
 
 	return (0);
+
+fail1:
+	EFSYS_PROBE1(fail1, efx_rc_t, rc);
+
+	return (rc);
 }
 
 static			void
diff --git a/sys/dev/sfxge/common/efx_mcdi.c b/sys/dev/sfxge/common/efx_mcdi.c
index 5d90daeaa96f..0f278303b7ca 100644
--- a/sys/dev/sfxge/common/efx_mcdi.c
+++ b/sys/dev/sfxge/common/efx_mcdi.c
@@ -1844,11 +1844,13 @@ efx_mcdi_mac_stats(
 	    MAC_STATS_IN_PERIOD_MS, (enable | events) ? period_ms : 0);
 
 	if (esmp != NULL) {
-		int bytes = MC_CMD_MAC_NSTATS * sizeof (uint64_t);
+		uint32_t bytes = MC_CMD_MAC_NSTATS * sizeof (uint64_t);
 
 		EFX_STATIC_ASSERT(MC_CMD_MAC_NSTATS * sizeof (uint64_t) <=
 		    EFX_MAC_STATS_SIZE);
 
+		EFSYS_ASSERT3U(bytes, <=, (uint32_t)EFSYS_MEM_SIZE(esmp));
+
 		MCDI_IN_SET_DWORD(req, MAC_STATS_IN_DMA_ADDR_LO,
 			    EFSYS_MEM_ADDR(esmp) & 0xffffffff);
 		MCDI_IN_SET_DWORD(req, MAC_STATS_IN_DMA_ADDR_HI,
diff --git a/sys/dev/sfxge/common/siena_phy.c b/sys/dev/sfxge/common/siena_phy.c
index 3cbc72aa9fa1..aeba92338b2a 100644
--- a/sys/dev/sfxge/common/siena_phy.c
+++ b/sys/dev/sfxge/common/siena_phy.c
@@ -563,6 +563,11 @@ siena_phy_stats_update(
 			    MC_CMD_PHY_STATS_OUT_DMA_LEN)];
 	efx_rc_t rc;
 
+	if ((esmp == NULL) || (EFSYS_MEM_SIZE(esmp) < EFX_PHY_STATS_SIZE)) {
+		rc = EINVAL;
+		goto fail1;
+	}
+
 	(void) memset(payload, 0, sizeof (payload));
 	req.emr_cmd = MC_CMD_PHY_STATS;
 	req.emr_in_buf = payload;
@@ -579,7 +584,7 @@ siena_phy_stats_update(
 
 	if (req.emr_rc != 0) {
 		rc = req.emr_rc;
-		goto fail1;
+		goto fail2;
 	}
 	EFSYS_ASSERT3U(req.emr_out_length, ==, MC_CMD_PHY_STATS_OUT_DMA_LEN);
 
@@ -588,6 +593,8 @@ siena_phy_stats_update(
 
 	return (0);
 
+fail2:
+	EFSYS_PROBE(fail2);
 fail1:
 	EFSYS_PROBE1(fail1, efx_rc_t, rc);
 
diff --git a/sys/dev/sfxge/sfxge_dma.c b/sys/dev/sfxge/sfxge_dma.c
index f75fab016897..52b4403b3f97 100644
--- a/sys/dev/sfxge/sfxge_dma.c
+++ b/sys/dev/sfxge/sfxge_dma.c
@@ -136,6 +136,7 @@ sfxge_dma_free(efsys_mem_t *esmp)
 
 	esmp->esm_addr = 0;
 	esmp->esm_base = NULL;
+	esmp->esm_size = 0;
 }
 
 int
@@ -175,6 +176,7 @@ sfxge_dma_alloc(struct sfxge_softc *sc, bus_size_t len, efsys_mem_t *esmp)
 		goto fail_load_check;
 
 	esmp->esm_base = vaddr;
+	esmp->esm_size = len;
 
 	return (0);