jump-target-check.patch

   1 ---
   2
   3  source/interpret.c |   13 ++++++++-----
   4  source/interpret.h |    1 +
   5  2 files changed, 9 insertions(+), 5 deletions(-)
   6
   7 diff --quilt old/source/interpret.c new/source/interpret.c
   8 --- old/source/interpret.c
   9 +++ new/source/interpret.c
  10 @@ -292,17 +292,16 @@ AccumulatorData *BeginCreatingProgram(co
  11  Program *FinishCreatingProgram(AccumulatorData *old)
  12  {
  13      Program *newProg;
  14 -    int progLen;
  15
  16      newProg = XtNew(Program);
  17      newProg->name = LookupString(ProgramName, True);
  18 -    progLen = ProgP - Prog;
  19 -    newProg->code = (Inst *)XtCalloc(progLen, sizeof(Inst));
  20 -    memcpy(newProg->code, Prog, progLen * sizeof(Inst));
  21 +    newProg->progLen = ProgP - Prog;
  22 +    newProg->code = (Inst *)XtCalloc(newProg->progLen, sizeof(Inst));
  23 +    memcpy(newProg->code, Prog, newProg->progLen * sizeof(Inst));
  24      newProg->nested   = False;
  25      newProg->refcount = 0;
  26
  27 -    DISASM(newProg->name, newProg->code, ProgP - Prog);
  28 +    DISASM(newProg->name, newProg->code, newProg->progLen);
  29
  30      XtFree((char *)Accumulator);
  31      Accumulator = old;
  32 @@ -1265,6 +1264,10 @@ static void addToGlobalSymTab(Symbol *sy
  33
  34  #define JUMP(a) \
  35      do { \
  36 +        Program *prog = FP_GET_PROG(FrameP); \
  37 +        if (!(prog->code <= (a) && (a) < (prog->code + prog->progLen))) { \
  38 +            EXEC_ERROR("Branch target outside current frame", NULL); \
  39 +        } \
  40          PC = (a); \
  41      } while (0)
  42
  43 diff --quilt old/source/interpret.h new/source/interpret.h
  44 --- old/source/interpret.h
  45 +++ new/source/interpret.h
  46 @@ -122,6 +122,7 @@ typedef struct SymbolRec {
  47
  48  typedef struct ProgramTag {
  49      const char *name;
  50 +    unsigned progLen;
  51      Inst *code;
  52      unsigned nested:1;
  53      unsigned refcount:31;