Check if destinations are too distant; fix #3900 fix #3901

1 files changed, 19 insertions, 3 deletions

diff --git a/mrbgems/mruby-compiler/core/codegen.c b/mrbgems/mruby-compiler/core/codegen.c
index 460368f88..c4227ca8e 100644
--- a/mrbgems/mruby-compiler/core/codegen.c
+++ b/mrbgems/mruby-compiler/core/codegen.c
@@ -392,6 +392,14 @@ scope_error(codegen_scope *s)
   exit(EXIT_FAILURE);
 }
 
+static void
+distcheck(codegen_scope *s, int diff)
+{
+  if (diff > MAXARG_sBx || diff < -MAXARG_sBx) {
+    codegen_error(s, "too distant jump address");
+  }
+}
+
 static inline void
 dispatch(codegen_scope *s, int pc)
 {
@@ -413,9 +421,7 @@ dispatch(codegen_scope *s, int pc)
     scope_error(s);
     break;
   }
-  if (diff > MAXARG_sBx) {
-    codegen_error(s, "too distant jump address");
-  }
+  distcheck(s, diff);
   s->iseq[pc] = MKOP_AsBx(c, GETARG_A(i), diff);
 }
 
@@ -1364,6 +1370,7 @@ codegen(codegen_scope *s, node *tree, int val)
               pop();
               genop(s, MKOP_ABC(OP_RESCUE, exc, cursp(), 1));
             }
+            distcheck(s, pos2);
             tmp = genop(s, MKOP_AsBx(OP_JMPIF, cursp(), pos2));
             pos2 = tmp;
             if (n4) {
@@ -1381,6 +1388,7 @@ codegen(codegen_scope *s, node *tree, int val)
             codegen(s, n3->cdr->cdr->car, val);
             if (val) pop();
           }
+          distcheck(s, exend);
           tmp = genop(s, MKOP_sBx(OP_JMP, exend));
           exend = tmp;
           n2 = n2->cdr;
@@ -1526,6 +1534,7 @@ codegen(codegen_scope *s, node *tree, int val)
       dispatch(s, lp->pc1);
       codegen(s, tree->car, VAL);
       pop();
+      distcheck(s, lp->pc2 - s->pc);
       genop(s, MKOP_AsBx(OP_JMPIF, cursp(), lp->pc2 - s->pc));
 
       loop_pop(s, val);
@@ -1542,6 +1551,7 @@ codegen(codegen_scope *s, node *tree, int val)
       dispatch(s, lp->pc1);
       codegen(s, tree->car, VAL);
       pop();
+      distcheck(s, lp->pc2 - s->pc);
       genop(s, MKOP_AsBx(OP_JMPNOT, cursp(), lp->pc2 - s->pc));
 
       loop_pop(s, val);
@@ -1584,6 +1594,7 @@ codegen(codegen_scope *s, node *tree, int val)
           else {
             pop();
           }
+          distcheck(s, pos2);
           tmp = genop(s, MKOP_AsBx(OP_JMPIF, cursp(), pos2));
           pos2 = tmp;
           n = n->cdr;
@@ -1594,6 +1605,7 @@ codegen(codegen_scope *s, node *tree, int val)
         }
         codegen(s, tree->car->cdr, val);
         if (val) pop();
+        distcheck(s, pos3);
         tmp = genop(s, MKOP_sBx(OP_JMP, pos3));
         pos3 = tmp;
         if (pos1) dispatch(s, pos1);
@@ -2091,6 +2103,7 @@ codegen(codegen_scope *s, node *tree, int val)
         genop_peep(s, MKOP_A(OP_EPOP, s->ensure_level - s->loop->ensure_level), NOVAL);
       }
       codegen(s, tree, NOVAL);
+      distcheck(s, s->loop->pc1 - s->pc);
       genop(s, MKOP_sBx(OP_JMP, s->loop->pc1 - s->pc));
     }
     else {
@@ -2114,6 +2127,7 @@ codegen(codegen_scope *s, node *tree, int val)
       if (s->ensure_level > s->loop->ensure_level) {
         genop_peep(s, MKOP_A(OP_EPOP, s->ensure_level - s->loop->ensure_level), NOVAL);
       }
+      distcheck(s, s->loop->pc2 - s->pc);
       genop(s, MKOP_sBx(OP_JMP, s->loop->pc2 - s->pc));
     }
     if (val) push();
@@ -2146,6 +2160,7 @@ codegen(codegen_scope *s, node *tree, int val)
           if (s->ensure_level > lp->ensure_level) {
             genop_peep(s, MKOP_A(OP_EPOP, s->ensure_level - lp->ensure_level), NOVAL);
           }
+          distcheck(s, s->loop->pc1 - s->pc);
           genop(s, MKOP_sBx(OP_JMP, lp->pc1 - s->pc));
         }
       }
@@ -3005,6 +3020,7 @@ loop_break(codegen_scope *s, node *tree)
       if (tree) {
         genop_peep(s, MKOP_AB(OP_MOVE, loop->acc, cursp()), NOVAL);
       }
+      distcheck(s, s->loop->pc3);
       tmp = genop(s, MKOP_sBx(OP_JMP, loop->pc3));
       loop->pc3 = tmp;
     }