On Thu, Aug 28, 2003 at 10:47:41AM -0400, Brian Almeida wrote: > On Thursday 28 August 2003 08:07 am, Brian Almeida wrote: > > [Please CC me as I am not subscribed to debian-x] > I got some more info by install xserver-xfree86-dbg and getting > a backtrace: > > Program received signal SIGSEGV, Segmentation fault. > 0x08649121 in __glXCreateDrawablePrivate (pDraw=0x8bd7f80, drawId=2097154, > modes=0x0) at glxutil.c:334 > 334 glxutil.c: No such file or directory. > in glxutil.c > (gdb) bt > #0 0x08649121 in __glXCreateDrawablePrivate (pDraw=0x8bd7f80, drawId=2097154, > modes=0x0) at glxutil.c:334 > #1 0x086493c3 in __glXGetDrawablePrivate (pDraw=0x8bd7f80, drawId=2097154, > modes=0x0) at glxutil.c:426 > #2 0x0866a032 in __glXMakeCurrent (cl=0x8bcfd50, pc=0x8bd03e0 "\232\005\004") > at glxcmds.c:484 > #3 0x08648607 in __glXDispatch (client=0x8bd01a8) at glxext.c:431 > #4 0x0845acc1 in Dispatch () at dispatch.c:450 > #5 0x084708b7 in main (argc=1, argv=0xbffffaf4, envp=0xbffffafc) at > main.c:469
Bad client data? The GLX extension is assuming that this "modes" thing
is a valid pointer. __glXCreateDrawablePrivate() is fed bullshit which
it gets from __glXGetDrawablePrivate(), which intern gets a pointer to a
structure that should be populated correctly by __glXMakeCurrent().
glxcmds.c:
360
/*****************************************************************************/
361 /*
362 ** Make an OpenGL context and drawable current.
363 */
364 int __glXMakeCurrent(__GLXclientState *cl, GLbyte *pc)
365 {
366 ClientPtr client = cl->client;
367 DrawablePtr pDraw;
368 xGLXMakeCurrentReq *req = (xGLXMakeCurrentReq *) pc;
369 xGLXMakeCurrentReply reply;
370 GLXDrawable drawId = req->drawable;
371 GLXContextID contextId = req->context;
372 __GLXpixmap *pGlxPixmap = 0;
373 __GLXcontext *glxc, *prevglxc;
^^^^^ Here's the guy that goes to hell.
374 __GLinterface *gc, *prevgc;
375 __GLXdrawablePrivate *glxPriv = NULL;
376 GLXContextTag tag = req->oldContextTag;
377 GLint error;
[...]
409 /*
410 ** Lookup new context. It must not be current for someone else.
411 */
412 if (contextId != None) {
413 glxc = (__GLXcontext *) LookupIDByType(contextId,
__glXContextRes);
414 if (!glxc) {
415 client->errorValue = contextId;
416 return __glXBadContext;
417 }
418 if ((glxc != prevglxc) && glxc->isCurrent) {
419 /* Context is current to somebody else */
420 return BadAccess;
421 }
422 gc = glxc->gc;
423 } else {
424 /* Switching to no context. Ignore new drawable. */
425 glxc = 0;
426 gc = 0;
427 }
The above if block is what initializes glxc.
The drawable then undergoes some auditing.
429 if (drawId != None) {
430 pDraw = (DrawablePtr) LookupDrawable(drawId, client);
431 if (pDraw) {
432 if (pDraw->type == DRAWABLE_WINDOW) {
433 /*
434 ** Drawable is an X Window.
435 */
436 WindowPtr pWin = (WindowPtr)pDraw;
437 VisualID vid = wVisual(pWin);
438
439 /*
440 ** Check if window and context are similar.
441 */
442 if ((vid != glxc->pVisual->vid) ||
443 (pWin->drawable.pScreen != glxc->pScreen)) {
444 client->errorValue = drawId;
445 return BadMatch;
446 }
447
448 } else {
449 /*
450 ** An X Pixmap is not allowed as a parameter (a GLX
Pixmap
451 ** is, but it must first be created with
glxCreateGLXPixmap).
452 */
453 client->errorValue = drawId;
454 return __glXBadDrawable;
455 }
456 } else {
457 pGlxPixmap = (__GLXpixmap *) LookupIDByType(drawId,
458 __glXPixmapRes);
459 if (pGlxPixmap) {
460 /*
461 ** Check if pixmap and context are similar.
462 */
463 if (pGlxPixmap->pScreen != glxc->pScreen ||
464 pGlxPixmap->pGlxVisual != glxc->pGlxVisual) {
465 client->errorValue = drawId;
466 return BadMatch;
467 }
468 pDraw = pGlxPixmap->pDraw;
469
470 } else {
471 /*
472 ** Drawable is neither a Window nor a GLXPixmap.
473 */
474 client->errorValue = drawId;
475 return __glXBadDrawable;
476 }
477 }
478 } else {
479 pDraw = 0;
480 }
481
482 /* get the drawable private */
483 if (pDraw) {
This is our last chance to audit glxc->modes before we pass it along.
Presumably we should have scrutinized glxc->modes above, but I don't
know what the spec says we should do for client->errorValue and the
return value.
484 glxPriv = __glXGetDrawablePrivate(pDraw, drawId, glxc->modes);
485 if (glxPriv == NULL) {
486 return __glXBadDrawable;
487 }
488 }
glxutil.c:
417 __GLXdrawablePrivate *
418 __glXGetDrawablePrivate(DrawablePtr pDraw, XID drawId,
419 __GLcontextModes *modes)
420 {
421 __GLXdrawablePrivate *glxPriv;
422
423 glxPriv = __glXFindDrawablePrivate(drawId);
424
425 if (glxPriv == NULL) {
426 glxPriv = __glXCreateDrawablePrivate(pDraw, drawId, modes);
427 if (glxPriv) {
428 __glXRefDrawablePrivate(glxPriv);
429 }
430 }
431
432 return glxPriv;
433 }
306 __GLXdrawablePrivate *
307 __glXCreateDrawablePrivate(DrawablePtr pDraw, XID drawId,
308 __GLcontextModes *modes)
309 {
310 __GLXdrawablePrivate *glxPriv;
311 __GLdrawablePrivate *glPriv;
312 __GLXscreenInfo *pGlxScreen;
313
314 glxPriv = (__GLXdrawablePrivate *) __glXMalloc(sizeof(*glxPriv));
315 __glXMemset(glxPriv, 0, sizeof(__GLXdrawablePrivate));
316
317 glxPriv->type = pDraw->type;
318 glxPriv->pDraw = pDraw;
319 glxPriv->drawId = drawId;
320
321 /* if not a pixmap, lookup will fail, so pGlxPixmap will be NULL */
322 glxPriv->pGlxPixmap = (__GLXpixmap *)
323 LookupIDByType(drawId, __glXPixmapRes);
324 /* since we are creating the drawablePrivate, drawId should be new
*/
325 if (!AddResource(drawId, __glXDrawableRes, glxPriv)) {
326 /* oops! */
327 __glXFree(glxPriv);
328 return NULL;
329 }
330
331 /* fill up glPriv */
332 glPriv = &glxPriv->glPriv;
333 glPriv->modes = (__GLcontextModes *)
__glXMalloc(sizeof(__GLcontextModes));
334 *glPriv->modes = *modes;
Boom. modes is a null pointer.
Someone knowledgeable about GLX know what to do about this?
--
G. Branden Robinson | The errors of great men are
Debian GNU/Linux | venerable because they are more
[EMAIL PROTECTED] | fruitful than the truths of little
http://people.debian.org/~branden/ | men. -- Friedrich Nietzsche
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