From: Gerhard Sittig <redacted>
Date: Sat, 10 Feb 2018 09:18:20 +0000 (+0100)
Subject: output/srzip: fix potential "use after free"
X-Git-Url: https://sigrok.org/gitaction?a=commitdiff_plain;h=f396351704d6875f72c858a3e16aa698b64ecc43;p=libsigrok.git

output/srzip: fix potential "use after free"

The compiler marks a potential use after free, which the current
implementation won't trigger. The error only occurs when a sigrok
channel is neither logic nor analog.

Address the issue nevertheless, to silence the compiler warning, and to
protect against possible programming errors when a future implementation
should support more channel types.

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

diff --git a/src/output/srzip.c b/src/output/srzip.c
index 84938ad2..db230576 100644
--- a/src/output/srzip.c
+++ b/src/output/srzip.c
@@ -150,6 +150,7 @@ static int zip_create(const struct sr_output *o)
 		if (!ch->enabled)
 			continue;
 
+		s = NULL;
 		switch (ch->type) {
 		case SR_CHANNEL_LOGIC:
 			s = g_strdup_printf("probe%d", ch->index + 1);
@@ -160,8 +161,10 @@ static int zip_create(const struct sr_output *o)
 			index++;
 			break;
 		}
-		g_key_file_set_string(meta, devgroup, s, ch->name);
-		g_free(s);
+		if (s) {
+			g_key_file_set_string(meta, devgroup, s, ch->name);
+			g_free(s);
+		}
 	}
 
 	metabuf = g_key_file_to_data(meta, &metalen, NULL);