From: Alexandru Gagniuc <redacted>
Date: Tue, 28 Apr 2015 20:03:58 +0000 (-0700)
Subject: asix-sigma: Avoid use of variable length arrays
X-Git-Tag: libsigrok-0.4.0~513
X-Git-Url: https://sigrok.org/gitaction?a=commitdiff_plain;h=e8686e3ae36c190a88f1a15aebb7294bb6491578;p=libsigrok.git

asix-sigma: Avoid use of variable length arrays

This was only done once in sigma_write_register().
---

diff --git a/src/hardware/asix-sigma/asix-sigma.c b/src/hardware/asix-sigma/asix-sigma.c
index 957b1d1a..6e7f1fd7 100644
--- a/src/hardware/asix-sigma/asix-sigma.c
+++ b/src/hardware/asix-sigma/asix-sigma.c
@@ -130,13 +130,23 @@ static int sigma_write(void *buf, size_t size, struct dev_context *devc)
 	return ret;
 }
 
+/*
+ * NOTE: We chose the buffer size to be large enough to hold any write to the
+ * device. We still print a message just in case.
+ */
 static int sigma_write_register(uint8_t reg, uint8_t *data, size_t len,
 				struct dev_context *devc)
 {
 	size_t i;
-	uint8_t buf[len + 2];
+	uint8_t buf[80];
 	int idx = 0;
 
+	if ((len + 2) > sizeof(buf)) {
+		sr_err("Attempted to write %zu bytes, but buffer is too small.",
+		       len + 2);
+		return SR_ERR_BUG;
+	}
+
 	buf[idx++] = REG_ADDR_LOW | (reg & 0xf);
 	buf[idx++] = REG_ADDR_HIGH | (reg >> 4);