chmod: bug handling comma after right hand ugo.

* sysif.c (chmod_wrap): The chm_comma state is transitioned to
after seeing a right hand side u, g or o. These do not combine
with other letters, so ch_comma expects a comma after which a
new permission clause we start,.  Therefore the srcm and who
variables must be rest.  It's also a good idea to continue the
loop.

* tests/018/chmod.tl: New test case which exposed
the above issue.

1 files changed, 1 insertions, 2 deletions

diff --git a/sysif.c b/sysif.c
index 44e236d7..8778a242 100644
--- a/sysif.c
+++ b/sysif.c
@@ -630,8 +630,7 @@ static val chmod_wrap(val target, val mode)
         case chm_comma:
           if (ch != ',')
             goto inval;
-          cs = chm_who;
-          break;
+          srcm = 0; who = 0; cs = chm_who; continue;
         }
 
         {