FIX : crash in SVGAParser

ZhuLida · ZhuLida · commit 79097670df0e · 2018-06-19T14:13:04.000+08:00
diff --git a/Source/SVGAParser.m b/Source/SVGAParser.m
@@ -184,6 +184,9 @@ - (void)parseWithData:(nonnull NSData *)data
         }
         return;
     }
+    if (!data || data.length < 5) {
+        return;
+    }
     NSData *tag = [data subdataWithRange:NSMakeRange(0, 4)];
     if (![[tag description] isEqualToString:@"<504b0304>"]) {
         // Maybe is SVGA 2.0.0

Original file line number	Diff line number	Diff line change
`@@ -184,6 +184,9 @@ - (void)parseWithData:(nonnull NSData *)data`
`184`	`184`	`}`
`185`	`185`	`return;`
`186`	`186`	`}`
	`187`	`+ if (!data \|\| data.length < 5) {`
	`188`	`+ return;`
	`189`	`+ }`
`187`	`190`	`NSData *tag = [data subdataWithRange:NSMakeRange(0, 4)];`
`188`	`191`	`if (![[tag description] isEqualToString:@"<504b0304>"]) {`
`189`	`192`	`// Maybe is SVGA 2.0.0`