1 files changed, 23 insertions, 13 deletions

diff --git a/shell/ash.c b/shell/ash.c
index ad7b8f4dd..b82c51029 100644
--- a/shell/ash.c
+++ b/shell/ash.c
@@ -13747,6 +13747,10 @@ expandstr(const char *ps, int syntax_type)
 {
         union node n;
         int saveprompt;
+        struct parsefile *file_stop = g_parsefile;
+        volatile int saveint;
+        struct jmploc *volatile savehandler = exception_handler;
+        struct jmploc jmploc;
 
         /* XXX Fix (char *) cast. */
         setinputstring((char *)ps);
@@ -13758,29 +13762,35 @@ expandstr(const char *ps, int syntax_type)
          * Try a prompt with syntactically wrong command:
          * PS1='$(date "+%H:%M:%S) > '
          */
-        {
-                volatile int saveint;
-                struct jmploc *volatile savehandler = exception_handler;
-                struct jmploc jmploc;
-                SAVE_INT(saveint);
-                if (setjmp(jmploc.loc) == 0) {
-                        exception_handler = &jmploc;
-                        readtoken1(pgetc(), syntax_type, FAKEEOFMARK, 0);
-                }
-                exception_handler = savehandler;
-                RESTORE_INT(saveint);
+        SAVE_INT(saveint);
+        if (setjmp(jmploc.loc) == 0) {
+                exception_handler = &jmploc;
+                readtoken1(pgetc(), syntax_type, FAKEEOFMARK, 0);
         }
+        exception_handler = savehandler;
+        RESTORE_INT(saveint);
 
         doprompt = saveprompt;
 
-        popfile();
+        /* Try: PS1='`xxx(`' */
+        unwindfiles(file_stop);
 
         n.narg.type = NARG;
         n.narg.next = NULL;
         n.narg.text = wordtext;
         n.narg.backquote = backquotelist;
 
-        expandarg(&n, NULL, EXP_QUOTED);
+        /* expandarg() might fail too:
+         * PS1='$((123+))'
+         */
+        SAVE_INT(saveint);
+        if (setjmp(jmploc.loc) == 0) {
+                exception_handler = &jmploc;
+                expandarg(&n, NULL, EXP_QUOTED);
+        }
+        exception_handler = savehandler;
+        RESTORE_INT(saveint);
+
         return stackblock();
 }