Re: [PATCH] drm/lease: Limit amount of maximum objects per lease.
From: kernel test robot
Date: Thu May 28 2026 - 06:01:41 EST
Hi Maarten,
kernel test robot noticed the following build warnings:
[auto build test WARNING on drm-misc/drm-misc-next]
[also build test WARNING on akpm-mm/mm-everything daeinki-drm-exynos/exynos-drm-next drm/drm-next drm-i915/for-linux-next drm-i915/for-linux-next-fixes drm-tip/drm-tip linus/master v7.1-rc5 next-20260527]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Maarten-Lankhorst/drm-lease-Limit-amount-of-maximum-objects-per-lease/20260527-180216
base: https://gitlab.freedesktop.org/drm/misc/kernel.git drm-misc-next
patch link: https://lore.kernel.org/r/b3390013-f0de-4e23-a915-23340594fb49%40linux.intel.com
patch subject: [PATCH] drm/lease: Limit amount of maximum objects per lease.
config: hexagon-allmodconfig (https://download.01.org/0day-ci/archive/20260528/202605281701.Blefmpwd-lkp@xxxxxxxxx/config)
compiler: clang version 17.0.6 (https://github.com/llvm/llvm-project 6009708b4367171ccdbf4b5905cb6a803753fe18)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260528/202605281701.Blefmpwd-lkp@xxxxxxxxx/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@xxxxxxxxx>
| Closes: https://lore.kernel.org/oe-kbuild-all/202605281701.Blefmpwd-lkp@xxxxxxxxx/
All warnings (new ones prefixed by >>):
>> drivers/gpu/drm/drm_lease.c:513:50: warning: format specifies type 'long' but the argument has type 'size_t' (aka 'unsigned int') [-Wformat]
513 | drm_dbg_lease(dev, "too many objects (%ld)\n", object_count);
| ~~~ ^~~~~~~~~~~~
| %zu
include/drm/drm_print.h:663:54: note: expanded from macro 'drm_dbg_lease'
663 | drm_dev_dbg(__drm_to_dev(drm), DRM_UT_LEASE, fmt, ##__VA_ARGS__)
| ~~~ ^~~~~~~~~~~
include/drm/drm_print.h:563:39: note: expanded from macro 'drm_dev_dbg'
563 | __drm_dev_dbg(NULL, dev, cat, fmt, ##__VA_ARGS__)
| ~~~ ^~~~~~~~~~~
1 warning generated.
vim +513 drivers/gpu/drm/drm_lease.c
468
469 /*
470 * The master associated with the specified file will have a lease
471 * created containing the objects specified in the ioctl structure.
472 * A file descriptor will be allocated for that and returned to the
473 * application.
474 */
475 int drm_mode_create_lease_ioctl(struct drm_device *dev,
476 void *data, struct drm_file *lessor_priv)
477 {
478 struct drm_mode_create_lease *cl = data;
479 size_t object_count;
480 int ret = 0;
481 struct idr leases;
482 struct drm_master *lessor;
483 struct drm_master *lessee = NULL;
484 struct file *lessee_file = NULL;
485 struct file *lessor_file = lessor_priv->filp;
486 struct drm_file *lessee_priv;
487 int fd = -1;
488 uint32_t *object_ids;
489 static const size_t max_objects =
490 8 * sizeof(drm_crtc_mask(NULL)) +
491 8 * sizeof(drm_plane_mask(NULL)) +
492 8 * sizeof(drm_connector_mask(NULL));
493
494 /* Can't lease without MODESET */
495 if (!drm_core_check_feature(dev, DRIVER_MODESET))
496 return -EOPNOTSUPP;
497
498 if (cl->flags && (cl->flags & ~(O_CLOEXEC | O_NONBLOCK))) {
499 drm_dbg_lease(dev, "invalid flags\n");
500 return -EINVAL;
501 }
502
503 lessor = drm_file_get_master(lessor_priv);
504 /* Do not allow sub-leases */
505 if (lessor->lessor) {
506 drm_dbg_lease(dev, "recursive leasing not allowed\n");
507 ret = -EINVAL;
508 goto out_lessor;
509 }
510
511 object_count = cl->object_count;
512 if (object_count > max_objects) {
> 513 drm_dbg_lease(dev, "too many objects (%ld)\n", object_count);
514 ret = -EINVAL;
515 goto out_lessor;
516 }
517
518 /* Handle leased objects, if any */
519 idr_init(&leases);
520 if (object_count != 0) {
521 object_ids = memdup_array_user(u64_to_user_ptr(cl->object_ids),
522 object_count, sizeof(__u32));
523 if (IS_ERR(object_ids)) {
524 ret = PTR_ERR(object_ids);
525 idr_destroy(&leases);
526 goto out_lessor;
527 }
528
529 /* fill and validate the object idr */
530 ret = fill_object_idr(dev, lessor_priv, &leases,
531 object_count, object_ids);
532 kfree(object_ids);
533 if (ret) {
534 drm_dbg_lease(dev, "lease object lookup failed: %i\n", ret);
535 idr_destroy(&leases);
536 goto out_lessor;
537 }
538 }
539
540 /* Allocate a file descriptor for the lease */
541 fd = get_unused_fd_flags(cl->flags & (O_CLOEXEC | O_NONBLOCK));
542 if (fd < 0) {
543 idr_destroy(&leases);
544 ret = fd;
545 goto out_lessor;
546 }
547
548 drm_dbg_lease(dev, "Creating lease\n");
549 /* lessee will take the ownership of leases */
550 lessee = drm_lease_create(lessor, &leases);
551
552 if (IS_ERR(lessee)) {
553 ret = PTR_ERR(lessee);
554 idr_destroy(&leases);
555 goto out_leases;
556 }
557
558 /* Clone the lessor file to create a new file for us */
559 drm_dbg_lease(dev, "Allocating lease file\n");
560 lessee_file = file_clone_open(lessor_file);
561 if (IS_ERR(lessee_file)) {
562 ret = PTR_ERR(lessee_file);
563 goto out_lessee;
564 }
565
566 lessee_priv = lessee_file->private_data;
567 /* Change the file to a master one */
568 drm_master_put(&lessee_priv->master);
569 lessee_priv->master = lessee;
570 lessee_priv->is_master = 1;
571 lessee_priv->authenticated = 1;
572
573 /* Pass fd back to userspace */
574 drm_dbg_lease(dev, "Returning fd %d id %d\n", fd, lessee->lessee_id);
575 cl->fd = fd;
576 cl->lessee_id = lessee->lessee_id;
577
578 /* Hook up the fd */
579 fd_install(fd, lessee_file);
580
581 drm_master_put(&lessor);
582 drm_dbg_lease(dev, "drm_mode_create_lease_ioctl succeeded\n");
583 return 0;
584
585 out_lessee:
586 drm_master_put(&lessee);
587
588 out_leases:
589 put_unused_fd(fd);
590
591 out_lessor:
592 drm_master_put(&lessor);
593 drm_dbg_lease(dev, "drm_mode_create_lease_ioctl failed: %d\n", ret);
594 return ret;
595 }
596
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