[PATCH] parser: Catch bogus case patterns

[Herbert Xu <herbert@gondor.apana.org.au>]

Aleksander Ushakov <retes672@gmail.com> wrote:
>
>    case $PATH in 
>        *$PWD*)
>            echo \$PWD in \$PATH
>        ;;
>        ))

This is the cause of the issue in dash, an unexpected TRP token
causes an invalid word to be inserted into the case statement.

---8<---
If the token in a case statement pattern is not a TWORD, do not
insert it into the pattern list.  Instead abort the parsing with
a syntax error.

Reported-by: Aleksander Ushakov <retes672@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

diff --git a/src/parser.c b/src/parser.c
index 5714958..bbee1e3 100644
--- a/src/parser.c
+++ b/src/parser.c
@@ -442,6 +442,8 @@ next_case:
 			cp->type = NCLIST;
 			app = &cp->nclist.pattern;
 			for (;;) {
+				if (lasttoken != TWORD)
+					synexpect(TWORD);
 				*app = ap = (union node *)stalloc(sizeof (struct narg));
 				ap->type = NARG;
 				ap->narg.text = wordtext;
-- 
Email: Herbert Xu <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt