From: Gerhard Sittig <redacted>
Date: Fri, 9 Feb 2018 18:09:27 +0000 (+0100)
Subject: lascar-el-usb: fix potential NULL dereference and memory leak
X-Git-Url: http://sigrok.org/gitweb/?a=commitdiff_plain;h=b65adcedb89f69c7f52a6e98e73a3513c2648e95;p=libsigrok.git

lascar-el-usb: fix potential NULL dereference and memory leak

Check for successful allocation of multiple memory ranges, and release
partial allocations in the error path when one of them failed. This
fixes a potential memory leak, as well as avoids NULL dereferences.

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

diff --git a/src/hardware/lascar-el-usb/protocol.c b/src/hardware/lascar-el-usb/protocol.c
index 44f4be82..dcd83e8e 100644
--- a/src/hardware/lascar-el-usb/protocol.c
+++ b/src/hardware/lascar-el-usb/protocol.c
@@ -412,10 +412,13 @@ static void lascar_el_usb_dispatch(struct sr_dev_inst *sdi, unsigned char *buf,
 		packet.type = SR_DF_ANALOG;
 		packet.payload = &analog;
 		analog.meaning->mqflags = 0;
-		if (!(temp = g_try_malloc(sizeof(float) * samples)))
-			break;
-		if (!(rh = g_try_malloc(sizeof(float) * samples)))
+		temp = g_try_malloc(sizeof(float) * samples);
+		rh = g_try_malloc(sizeof(float) * samples);
+		if (!temp || !rh) {
+			g_free(temp);
+			g_free(rh);
 			break;
+		}
 		for (i = 0, j = 0; i < samples; i++) {
 			/* Both Celsius and Fahrenheit stored at base -40. */
 			if (devc->temp_unit == 0)