vacfs: fix segfault when no prefix specified

R=rsc CC=plan9port.codebot http://codereview.appspot.com/5451052
2011-11-30 15:20:43 -05:00 · 2011-11-30 15:20:43 -05:00 · aac05c4092
commit aac05c4092
parent 83a5aba766
1 changed files with 1 additions and 1 deletions
--- a/src/cmd/vac/file.c
+++ b/src/cmd/vac/file.c
@ -1774,7 +1774,7 @@ vacfsopen(VtConn *z, char *file, int mode, ulong cachemem)
 	char *prefix;
 	
 	if(vtparsescore(file, &prefix, score) >= 0){
-		if(strcmp(prefix, "vac") != 0){
+		if(prefix == nil || strcmp(prefix, "vac") != 0){
 			werrstr("not a vac file");
 			return nil;
 		}