diff --git a/cmd/zdb/zdb.c b/cmd/zdb/zdb.c
index a3a363ca5..a17793c2d 100644
--- a/cmd/zdb/zdb.c
+++ b/cmd/zdb/zdb.c
@@ -4418,9 +4418,14 @@ dump_l2arc_log_blocks(int fd, l2arc_dev_hdr_phys_t l2dhdr,
 		default:
 			abd = abd_alloc_for_io(asize, B_TRUE);
 			abd_copy_from_buf_off(abd, &this_lb, 0, asize);
-			zio_decompress_data(L2BLK_GET_COMPRESS(
+			if (zio_decompress_data(L2BLK_GET_COMPRESS(
 			    (&lbps[0])->lbp_prop), abd, &this_lb,
-			    asize, sizeof (this_lb), NULL);
+			    asize, sizeof (this_lb), NULL) != 0) {
+				(void) printf("L2ARC block decompression "
+				    "failed\n");
+				abd_free(abd);
+				goto out;
+			}
 			abd_free(abd);
 			break;
 		}
@@ -4455,7 +4460,7 @@ dump_l2arc_log_blocks(int fd, l2arc_dev_hdr_phys_t l2dhdr,
 		lbps[0] = lbps[1];
 		lbps[1] = this_lb.lb_prev_lbp;
 	}
-
+out:
 	if (!dump_opt['q']) {
 		(void) printf("log_blk_count:\t %llu with valid cksum\n",
 		    (u_longlong_t)rebuild->dh_lb_count);
@@ -7586,7 +7591,7 @@ dump_mos_leaks(spa_t *spa)
 		} else {
 			dmu_object_info_t doi;
 			const char *name;
-			dmu_object_info(mos, object, &doi);
+			VERIFY0(dmu_object_info(mos, object, &doi));
 			if (doi.doi_type & DMU_OT_NEWTYPE) {
 				dmu_object_byteswap_t bswap =
 				    DMU_OT_BYTESWAP(doi.doi_type);
@@ -8698,6 +8703,8 @@ main(int argc, char **argv)
 			usage();
 		dump_opt['v'] = verbose;
 		error = dump_path(argv[0], argv[1], &object);
+		if (error != 0)
+			fatal("internal error: %s", strerror(error));
 	}
 
 	if (dump_opt['X'] || dump_opt['F'])
diff --git a/cmd/zed/agents/zfs_retire.c b/cmd/zed/agents/zfs_retire.c
index a9e8baaa2..5fe56fe81 100644
--- a/cmd/zed/agents/zfs_retire.c
+++ b/cmd/zed/agents/zfs_retire.c
@@ -326,7 +326,8 @@ zfs_retire_recv(fmd_hdl_t *hdl, fmd_event_t *ep, nvlist_t *nvl,
 
 	fmd_hdl_debug(hdl, "zfs_retire_recv: '%s'", class);
 
-	nvlist_lookup_uint64(nvl, FM_EREPORT_PAYLOAD_ZFS_VDEV_STATE, &state);
+	(void) nvlist_lookup_uint64(nvl, FM_EREPORT_PAYLOAD_ZFS_VDEV_STATE,
+	    &state);
 
 	/*
 	 * If this is a resource notifying us of device removal then simply
diff --git a/cmd/zpool_influxdb/zpool_influxdb.c b/cmd/zpool_influxdb/zpool_influxdb.c
index 251d588d8..8440d8b57 100644
--- a/cmd/zpool_influxdb/zpool_influxdb.c
+++ b/cmd/zpool_influxdb/zpool_influxdb.c
@@ -265,7 +265,7 @@ get_vdev_name(nvlist_t *nvroot, const char *parent_name)
 	uint64_t vdev_id = 0;
 
 	char *vdev_type = (char *)"unknown";
-	nvlist_lookup_string(nvroot, ZPOOL_CONFIG_TYPE, &vdev_type);
+	(void) nvlist_lookup_string(nvroot, ZPOOL_CONFIG_TYPE, &vdev_type);
 
 	if (nvlist_lookup_uint64(
 	    nvroot, ZPOOL_CONFIG_ID, &vdev_id) != 0)
@@ -302,9 +302,9 @@ get_vdev_desc(nvlist_t *nvroot, const char *parent_name)
 	char *vdev_type = (char *)"unknown";
 	uint64_t vdev_id = UINT64_MAX;
 	char *vdev_path = NULL;
-	nvlist_lookup_string(nvroot, ZPOOL_CONFIG_TYPE, &vdev_type);
-	nvlist_lookup_uint64(nvroot, ZPOOL_CONFIG_ID, &vdev_id);
-	nvlist_lookup_string(nvroot, ZPOOL_CONFIG_PATH, &vdev_path);
+	(void) nvlist_lookup_string(nvroot, ZPOOL_CONFIG_TYPE, &vdev_type);
+	(void) nvlist_lookup_uint64(nvroot, ZPOOL_CONFIG_ID, &vdev_id);
+	(void) nvlist_lookup_string(nvroot, ZPOOL_CONFIG_PATH, &vdev_path);
 
 	if (parent_name == NULL) {
 		s = escape_string(vdev_type);
diff --git a/cmd/ztest.c b/cmd/ztest.c
index 0712f286b..b5a3d1810 100644
--- a/cmd/ztest.c
+++ b/cmd/ztest.c
@@ -2214,7 +2214,7 @@ ztest_replay_write(void *arg1, void *arg2, boolean_t byteswap)
 		dmu_write(os, lr->lr_foid, offset, length, data, tx);
 	} else {
 		memcpy(abuf->b_data, data, length);
-		dmu_assign_arcbuf_by_dbuf(db, offset, abuf, tx);
+		VERIFY0(dmu_assign_arcbuf_by_dbuf(db, offset, abuf, tx));
 	}
 
 	(void) ztest_log_write(zd, tx, lr);
diff --git a/lib/libzfsbootenv/lzbe_device.c b/lib/libzfsbootenv/lzbe_device.c
index 39e33324b..21007fd9e 100644
--- a/lib/libzfsbootenv/lzbe_device.c
+++ b/lib/libzfsbootenv/lzbe_device.c
@@ -74,6 +74,7 @@ lzbe_set_boot_device(const char *pool, lzbe_flags_t flag, const char *device)
 	/* version is mandatory */
 	fnvlist_add_uint64(nv, BOOTENV_VERSION, VB_NVLIST);
 
+	rv = 0;
 	/*
 	 * If device name is empty, remove boot device configuration.
 	 */
@@ -95,8 +96,8 @@ lzbe_set_boot_device(const char *pool, lzbe_flags_t flag, const char *device)
 				rv = ENOMEM;
 		}
 	}
-
-	rv = zpool_set_bootenv(zphdl, nv);
+	if (rv == 0)
+		rv = zpool_set_bootenv(zphdl, nv);
 	if (rv != 0)
 		fprintf(stderr, "%s\n", libzfs_error_description(hdl));
 
diff --git a/module/zfs/dmu_recv.c b/module/zfs/dmu_recv.c
index 55d03677f..0f3181f76 100644
--- a/module/zfs/dmu_recv.c
+++ b/module/zfs/dmu_recv.c
@@ -1874,6 +1874,8 @@ receive_object(struct receive_writer_arg *rwa, struct drr_object *drro,
 	if (err == 0) {
 		err = receive_handle_existing_object(rwa, drro, &doi, data,
 		    &object_to_hold, &new_blksz);
+		if (err != 0)
+			return (err);
 	} else if (err == EEXIST) {
 		/*
 		 * The object requested is currently an interior slot of a
diff --git a/module/zfs/dsl_dataset.c b/module/zfs/dsl_dataset.c
index 94b77aa1b..a7aca48aa 100644
--- a/module/zfs/dsl_dataset.c
+++ b/module/zfs/dsl_dataset.c
@@ -640,6 +640,8 @@ dsl_dataset_hold_obj(dsl_pool_t *dp, uint64_t dsobj, const void *tag,
 				    dsl_dataset_phys(ds)->ds_prev_snap_obj,
 				    ds, &ds->ds_prev);
 			}
+			if (err != 0)
+				goto after_dsl_bookmark_fini;
 			err = dsl_bookmark_init_ds(ds);
 		} else {
 			if (zfs_flags & ZFS_DEBUG_SNAPNAMES)
@@ -688,11 +690,11 @@ dsl_dataset_hold_obj(dsl_pool_t *dp, uint64_t dsobj, const void *tag,
 			winner = dmu_buf_set_user_ie(dbuf, &ds->ds_dbu);
 
 		if (err != 0 || winner != NULL) {
-			bplist_destroy(&ds->ds_pending_deadlist);
 			dsl_deadlist_close(&ds->ds_deadlist);
 			if (dsl_deadlist_is_open(&ds->ds_remap_deadlist))
 				dsl_deadlist_close(&ds->ds_remap_deadlist);
 			dsl_bookmark_fini_ds(ds);
+after_dsl_bookmark_fini:
 			if (ds->ds_prev)
 				dsl_dataset_rele(ds->ds_prev, ds);
 			dsl_dir_rele(ds->ds_dir, ds);
@@ -703,6 +705,7 @@ dsl_dataset_hold_obj(dsl_pool_t *dp, uint64_t dsobj, const void *tag,
 
 			list_destroy(&ds->ds_prop_cbs);
 			list_destroy(&ds->ds_sendstreams);
+			bplist_destroy(&ds->ds_pending_deadlist);
 			mutex_destroy(&ds->ds_lock);
 			mutex_destroy(&ds->ds_opening_lock);
 			mutex_destroy(&ds->ds_sendstream_lock);
diff --git a/module/zfs/dsl_dir.c b/module/zfs/dsl_dir.c
index a4db3ee2f..b32895946 100644
--- a/module/zfs/dsl_dir.c
+++ b/module/zfs/dsl_dir.c
@@ -270,7 +270,7 @@ dsl_dir_hold_obj(dsl_pool_t *dp, uint64_t ddobj,
 
 		if (dsl_dir_is_zapified(dd)) {
 			inode_timespec_t t = {0};
-			zap_lookup(dp->dp_meta_objset, ddobj,
+			(void) zap_lookup(dp->dp_meta_objset, ddobj,
 			    DD_FIELD_SNAPSHOTS_CHANGED,
 			    sizeof (uint64_t),
 			    sizeof (inode_timespec_t) / sizeof (uint64_t),
diff --git a/module/zfs/zfs_fm.c b/module/zfs/zfs_fm.c
index 47bb79a5d..a16c62675 100644
--- a/module/zfs/zfs_fm.c
+++ b/module/zfs/zfs_fm.c
@@ -1389,17 +1389,17 @@ zfs_post_state_change(spa_t *spa, vdev_t *vd, uint64_t laststate)
 	aux = fm_nvlist_create(NULL);
 	if (vd && aux) {
 		if (vd->vdev_physpath) {
-			(void) nvlist_add_string(aux,
+			fnvlist_add_string(aux,
 			    FM_EREPORT_PAYLOAD_ZFS_VDEV_PHYSPATH,
 			    vd->vdev_physpath);
 		}
 		if (vd->vdev_enc_sysfs_path) {
-			(void) nvlist_add_string(aux,
+			fnvlist_add_string(aux,
 			    FM_EREPORT_PAYLOAD_ZFS_VDEV_ENC_SYSFS_PATH,
 			    vd->vdev_enc_sysfs_path);
 		}
 
-		(void) nvlist_add_uint64(aux,
+		fnvlist_add_uint64(aux,
 		    FM_EREPORT_PAYLOAD_ZFS_VDEV_LASTSTATE, laststate);
 	}
 
@@ -1496,12 +1496,12 @@ zfs_ereport_zvol_post(const char *subclass, const char *name,
 		return;
 
 	aux = fm_nvlist_create(NULL);
-	nvlist_add_string(aux, FM_EREPORT_PAYLOAD_ZFS_DEVICE_NAME, dev_name);
-	nvlist_add_string(aux, FM_EREPORT_PAYLOAD_ZFS_RAW_DEVICE_NAME,
+	fnvlist_add_string(aux, FM_EREPORT_PAYLOAD_ZFS_DEVICE_NAME, dev_name);
+	fnvlist_add_string(aux, FM_EREPORT_PAYLOAD_ZFS_RAW_DEVICE_NAME,
 	    raw_name);
 	r = strchr(name, '/');
 	if (r && r[1])
-		nvlist_add_string(aux, FM_EREPORT_PAYLOAD_ZFS_VOLUME, &r[1]);
+		fnvlist_add_string(aux, FM_EREPORT_PAYLOAD_ZFS_VOLUME, &r[1]);
 
 	zfs_post_common(spa, NULL, FM_RSRC_CLASS, subclass, aux);
 	fm_nvlist_destroy(aux, FM_NVA_FREE);
diff --git a/module/zfs/zvol.c b/module/zfs/zvol.c
index 3a1870f56..2e2860ff0 100644
--- a/module/zfs/zvol.c
+++ b/module/zfs/zvol.c
@@ -429,7 +429,7 @@ zvol_replay_truncate(void *arg1, void *arg2, boolean_t byteswap)
 	if (error != 0) {
 		dmu_tx_abort(tx);
 	} else {
-		zil_replaying(zv->zv_zilog, tx);
+		(void) zil_replaying(zv->zv_zilog, tx);
 		dmu_tx_commit(tx);
 		error = dmu_free_long_range(zv->zv_objset, ZVOL_OBJ, offset,
 		    length);
@@ -475,7 +475,7 @@ zvol_replay_write(void *arg1, void *arg2, boolean_t byteswap)
 		dmu_tx_abort(tx);
 	} else {
 		dmu_write(os, ZVOL_OBJ, offset, length, data, tx);
-		zil_replaying(zv->zv_zilog, tx);
+		(void) zil_replaying(zv->zv_zilog, tx);
 		dmu_tx_commit(tx);
 	}
 
diff --git a/tests/zfs-tests/cmd/draid.c b/tests/zfs-tests/cmd/draid.c
index b995be46a..831039288 100644
--- a/tests/zfs-tests/cmd/draid.c
+++ b/tests/zfs-tests/cmd/draid.c
@@ -139,7 +139,7 @@ read_map_key(const char *filename, const char *key, nvlist_t **cfg)
 	if (error != 0)
 		return (error);
 
-	nvlist_lookup_nvlist(allcfgs, key, &foundcfg);
+	(void) nvlist_lookup_nvlist(allcfgs, key, &foundcfg);
 	if (foundcfg != NULL) {
 		nvlist_dup(foundcfg, cfg, KM_SLEEP);
 		error = 0;
@@ -375,7 +375,7 @@ dump_map_nv(const char *key, nvlist_t *cfg, int verbose)
 	map.dm_checksum = fnvlist_lookup_uint64(cfg, MAP_CHECKSUM);
 	map.dm_children = fnvlist_lookup_uint64(cfg, MAP_CHILDREN);
 	map.dm_nperms = fnvlist_lookup_uint64(cfg, MAP_NPERMS);
-	nvlist_lookup_uint8_array(cfg, MAP_PERMS, &map.dm_perms, &c);
+	map.dm_perms = fnvlist_lookup_uint8_array(cfg, MAP_PERMS, &c);
 
 	dump_map(&map, key, (double)worst_ratio / 1000.0,
 	    avg_ratio / 1000.0, verbose);
diff --git a/tests/zfs-tests/cmd/file/file_fadvise.c b/tests/zfs-tests/cmd/file/file_fadvise.c
index e1afb6d0a..d64e2dea3 100644
--- a/tests/zfs-tests/cmd/file/file_fadvise.c
+++ b/tests/zfs-tests/cmd/file/file_fadvise.c
@@ -89,7 +89,11 @@ main(int argc, char *argv[])
 		return (1);
 	}
 
-	posix_fadvise(fd, 0, 0, advise);
+	if (posix_fadvise(fd, 0, 0, advise) != 0) {
+		perror("posix_fadvise");
+		close(fd);
+		return (1);
+	}
 
 	close(fd);
 
diff --git a/tests/zfs-tests/cmd/mmap_sync.c b/tests/zfs-tests/cmd/mmap_sync.c
index 0e4bba37d..618f1284a 100644
--- a/tests/zfs-tests/cmd/mmap_sync.c
+++ b/tests/zfs-tests/cmd/mmap_sync.c
@@ -32,7 +32,7 @@
 static void
 cleanup(char *file)
 {
-	remove(file);
+	(void) remove(file);
 }
 
 int
@@ -125,7 +125,8 @@ main(int argc, char *argv[])
 		elapsed += ((t2.tv_usec - t1.tv_usec) / 1000.0);
 		if (elapsed > max_msync_time_ms) {
 			fprintf(stderr, "slow msync: %f ms\n", elapsed);
-			munmap(ptr, LEN);
+			if (munmap(ptr, LEN) != 0)
+				perror("munmap");
 			cleanup(file);
 			return (1);
 		}
diff --git a/tests/zfs-tests/cmd/mmapwrite.c b/tests/zfs-tests/cmd/mmapwrite.c
index 0d277d6e3..8534db339 100644
--- a/tests/zfs-tests/cmd/mmapwrite.c
+++ b/tests/zfs-tests/cmd/mmapwrite.c
@@ -73,7 +73,11 @@ normal_writer(void *filename)
 			err(1, "write failed!");
 			break;
 		}
-		lseek(fd, page_size, SEEK_CUR);
+		if (lseek(fd, page_size, SEEK_CUR) == -1) {
+			err(1, "lseek failed on %s: %s", file_path,
+			    strerror(errno));
+			break;
+		}
 	}
 }