From: Gerhard Sittig <redacted>
Date: Sat, 10 Feb 2018 11:20:05 +0000 (+0100)
Subject: hameg-hmo: fix potential NULL dereference
X-Git-Url: https://sigrok.org/gitaction?a=commitdiff_plain;h=eac9fcd2685a0068a9c9884a2b96629088a20ca5;p=libsigrok.git

hameg-hmo: fix potential NULL dereference

Check for successful allocation before accessing struct members. Return
with an error from device initialization when allocation fails.

This was reported by clang's scan-build.
---

diff --git a/src/hardware/hameg-hmo/protocol.c b/src/hardware/hameg-hmo/protocol.c
index e79901ca..059ae439 100644
--- a/src/hardware/hameg-hmo/protocol.c
+++ b/src/hardware/hameg-hmo/protocol.c
@@ -664,6 +664,7 @@ SR_PRIV int hmo_init_device(struct sr_dev_inst *sdi)
 	unsigned int i, j, group;
 	struct sr_channel *ch;
 	struct dev_context *devc;
+	int ret;
 
 	devc = sdi->priv;
 	model_index = -1;
@@ -711,12 +712,19 @@ SR_PRIV int hmo_init_device(struct sr_dev_inst *sdi)
 	}
 
 	/* Add digital channel groups. */
+	ret = SR_OK;
 	for (i = 0; i < scope_models[model_index].digital_pods; i++) {
 		devc->digital_groups[i] = g_malloc0(sizeof(struct sr_channel_group));
+		if (!devc->digital_groups[i]) {
+			ret = SR_ERR_MALLOC;
+			break;
+		}
 		devc->digital_groups[i]->name = g_strdup_printf("POD%d", i);
 		sdi->channel_groups = g_slist_append(sdi->channel_groups,
 				   devc->digital_groups[i]);
 	}
+	if (ret != SR_OK)
+		return ret;
 
 	/* Add digital channels. */
 	for (i = 0; i < scope_models[model_index].digital_channels; i++) {