Re: [syzbot] [mm?] WARNING in alloc_frozen_pages_noprof (2)

Re: [syzbot] [mm?] WARNING in alloc_frozen_pages_noprof (2)

[Andrew Morton]

On Mon, 25 May 2026 19:49:23 -0700 syzbot <syzbot+5d32c8bd82427f9c77cc@syzkaller.appspotmail.com> wrote:

> Hello,
> 
> syzbot found the following issue on:
> 
> HEAD commit:    4cbfe4502e3d Merge tag 'v7.1-rc5-ksmbd-server-fixes' of gi..
> git tree:       https://kernel.googlesource.com/pub/scm/linux/kernel/git/torvalds/linux master
> console output: https://syzkaller.appspot.com/x/log.txt?x=146c161f980000
> kernel config:  https://syzkaller.appspot.com/x/.config?x=9475bd041c93289
> dashboard link: https://syzkaller.appspot.com/bug?extid=5d32c8bd82427f9c77cc
> compiler:       aarch64-linux-gnu-gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44
> userspace arch: arm64
> syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=11026336580000
> C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=14ab9796580000

Thanks.

> Downloadable assets:
> disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/fa3fbcfdac58/non_bootable_disk-4cbfe450.raw.xz
> vmlinux: https://storage.googleapis.com/syzbot-assets/e825a08fb48d/vmlinux-4cbfe450.xz
> kernel image: https://storage.googleapis.com/syzbot-assets/55037c053ec3/Image-4cbfe450.gz.xz
> 
> IMPORTANT: if you fix the issue, please add the following tag to the commit:
> Reported-by: syzbot+5d32c8bd82427f9c77cc@syzkaller.appspotmail.com
> 
> ------------[ cut here ]------------
> WARNING: mm/page_alloc.c:5202 at __alloc_frozen_pages_noprof+0x734/0x1144 mm/page_alloc.c:5202, CPU#0: syz.2.17/3592

	if (WARN_ON_ONCE_GFP(order > MAX_PAGE_ORDER, gfp))

> Modules linked in:
> CPU: 0 UID: 0 PID: 3592 Comm: syz.2.17 Not tainted syzkaller #0 PREEMPT 
> Hardware name: linux,dummy-virt (DT)
> pstate: 21402009 (nzCv daif +PAN -UAO -TCO +DIT -SSBS BTYPE=--)
> pc : __alloc_frozen_pages_noprof+0x734/0x1144 mm/page_alloc.c:5202
> lr : alloc_pages_mpol+0x70/0x1a4 mm/mempolicy.c:2490
> sp : ffff800085d93900
> x29: ffff800085d93a00 x28: 000000000000000b x27: 0000000000000000
> x26: 0000000000000000 x25: fcf0000014c00000 x24: 0000000000040dc0
> x23: 0000000000000000 x22: 0000000000000000 x21: 000000000000000b
> x20: ffffffffffffffff x19: 0000000000000000 x18: 0000000000000002
> x17: 0000000000000000 x16: 0000000000000000 x15: 0000000020000200
> x14: ffff8000828b2000 x13: ffffc1ffc0000000 x12: 0000000000000001
> x11: 0000000000000000 x10: ffff800082b6f4e8 x9 : 0000000000000000
> x8 : 0000000000000030 x7 : ffff800082e9b430 x6 : 0000000000000001
> x5 : 0000000000000000 x4 : f3f00000065c90c0 x3 : 0000000000000000
> x2 : 0000000000000000 x1 : 0000000000000001 x0 : ffff800082dfd000
> Call trace:
>  __alloc_frozen_pages_noprof+0x734/0x1144 mm/page_alloc.c:5202 (P)
>  alloc_pages_mpol+0x70/0x1a4 mm/mempolicy.c:2490
>  alloc_frozen_pages_noprof+0x48/0xd4 mm/mempolicy.c:2561
>  ___kmalloc_large_node+0x11c/0x13c mm/slub.c:5237
>  __kmalloc_large_node_noprof mm/slub.c:5268 [inline]
>  __do_kmalloc_node mm/slub.c:5284 [inline]
>  __kmalloc_noprof+0x450/0x560 mm/slub.c:5308
>  kmalloc_noprof include/linux/slab.h:954 [inline]
>  kzalloc_noprof include/linux/slab.h:1188 [inline]
>  fill_object_idr drivers/gpu/drm/drm_lease.c:389 [inline]
>  drm_mode_create_lease_ioctl+0x184/0x93c drivers/gpu/drm/drm_lease.c:521
>  drm_ioctl_kernel+0xc0/0x130 drivers/gpu/drm/drm_ioctl.c:804
>  drm_ioctl+0x258/0x580 drivers/gpu/drm/drm_ioctl.c:901
>  vfs_ioctl fs/ioctl.c:51 [inline]

Methinks drm_mode_create_lease_ioctl() wants some more arg checking.

otoh, memdup_user() passes __GFP_NOWARN, so perhaps
__alloc_frozen_pages_noprof() should be taught to honor that.

>  __do_sys_ioctl fs/ioctl.c:597 [inline]
>  __se_sys_ioctl fs/ioctl.c:583 [inline]
>  __arm64_sys_ioctl+0xac/0x104 fs/ioctl.c:583
>  __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
>  invoke_syscall+0x54/0x10c arch/arm64/kernel/syscall.c:49
>  el0_svc_common.constprop.0+0x40/0xe0 arch/arm64/kernel/syscall.c:121
>  do_el0_svc+0x1c/0x34 arch/arm64/kernel/syscall.c:140
>  el0_svc+0x38/0x140 arch/arm64/kernel/entry-common.c:740
>  el0t_64_sync_handler+0xa0/0xf0 arch/arm64/kernel/entry-common.c:759
>  el0t_64_sync+0x1a4/0x1a8 arch/arm64/kernel/entry.S:594
> ---[ end trace 0000000000000000 ]---

[PATCH] drm/lease: Limit amount of maximum objects per lease.

[Maarten Lankhorst]

Hey,

Den 2026-05-26 kl. 21:58, skrev Andrew Morton:
> On Mon, 25 May 2026 19:49:23 -0700 syzbot <syzbot+5d32c8bd82427f9c77cc@syzkaller.appspotmail.com> wrote:
> 
>> Hello,
>>
>> syzbot found the following issue on:
>>
>> HEAD commit:    4cbfe4502e3d Merge tag 'v7.1-rc5-ksmbd-server-fixes' of gi..
>> git tree:       https://kernel.googlesource.com/pub/scm/linux/kernel/git/torvalds/linux master
>> console output: https://syzkaller.appspot.com/x/log.txt?x=146c161f980000
>> kernel config:  https://syzkaller.appspot.com/x/.config?x=9475bd041c93289
>> dashboard link: https://syzkaller.appspot.com/bug?extid=5d32c8bd82427f9c77cc
>> compiler:       aarch64-linux-gnu-gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44
>> userspace arch: arm64
>> syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=11026336580000
>> C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=14ab9796580000
> 
> Thanks.
> 
>> Downloadable assets:
>> disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/fa3fbcfdac58/non_bootable_disk-4cbfe450.raw.xz
>> vmlinux: https://storage.googleapis.com/syzbot-assets/e825a08fb48d/vmlinux-4cbfe450.xz
>> kernel image: https://storage.googleapis.com/syzbot-assets/55037c053ec3/Image-4cbfe450.gz.xz
>>
>> IMPORTANT: if you fix the issue, please add the following tag to the commit:
>> Reported-by: syzbot+5d32c8bd82427f9c77cc@syzkaller.appspotmail.com
>>
>> ------------[ cut here ]------------
>> WARNING: mm/page_alloc.c:5202 at __alloc_frozen_pages_noprof+0x734/0x1144 mm/page_alloc.c:5202, CPU#0: syz.2.17/3592
> 
> 	if (WARN_ON_ONCE_GFP(order > MAX_PAGE_ORDER, gfp))
> 
>> Modules linked in:
>> CPU: 0 UID: 0 PID: 3592 Comm: syz.2.17 Not tainted syzkaller #0 PREEMPT 
>> Hardware name: linux,dummy-virt (DT)
>> pstate: 21402009 (nzCv daif +PAN -UAO -TCO +DIT -SSBS BTYPE=--)
>> pc : __alloc_frozen_pages_noprof+0x734/0x1144 mm/page_alloc.c:5202
>> lr : alloc_pages_mpol+0x70/0x1a4 mm/mempolicy.c:2490
>> sp : ffff800085d93900
>> x29: ffff800085d93a00 x28: 000000000000000b x27: 0000000000000000
>> x26: 0000000000000000 x25: fcf0000014c00000 x24: 0000000000040dc0
>> x23: 0000000000000000 x22: 0000000000000000 x21: 000000000000000b
>> x20: ffffffffffffffff x19: 0000000000000000 x18: 0000000000000002
>> x17: 0000000000000000 x16: 0000000000000000 x15: 0000000020000200
>> x14: ffff8000828b2000 x13: ffffc1ffc0000000 x12: 0000000000000001
>> x11: 0000000000000000 x10: ffff800082b6f4e8 x9 : 0000000000000000
>> x8 : 0000000000000030 x7 : ffff800082e9b430 x6 : 0000000000000001
>> x5 : 0000000000000000 x4 : f3f00000065c90c0 x3 : 0000000000000000
>> x2 : 0000000000000000 x1 : 0000000000000001 x0 : ffff800082dfd000
>> Call trace:
>>  __alloc_frozen_pages_noprof+0x734/0x1144 mm/page_alloc.c:5202 (P)
>>  alloc_pages_mpol+0x70/0x1a4 mm/mempolicy.c:2490
>>  alloc_frozen_pages_noprof+0x48/0xd4 mm/mempolicy.c:2561
>>  ___kmalloc_large_node+0x11c/0x13c mm/slub.c:5237
>>  __kmalloc_large_node_noprof mm/slub.c:5268 [inline]
>>  __do_kmalloc_node mm/slub.c:5284 [inline]
>>  __kmalloc_noprof+0x450/0x560 mm/slub.c:5308
>>  kmalloc_noprof include/linux/slab.h:954 [inline]
>>  kzalloc_noprof include/linux/slab.h:1188 [inline]
>>  fill_object_idr drivers/gpu/drm/drm_lease.c:389 [inline]
>>  drm_mode_create_lease_ioctl+0x184/0x93c drivers/gpu/drm/drm_lease.c:521
>>  drm_ioctl_kernel+0xc0/0x130 drivers/gpu/drm/drm_ioctl.c:804
>>  drm_ioctl+0x258/0x580 drivers/gpu/drm/drm_ioctl.c:901
>>  vfs_ioctl fs/ioctl.c:51 [inline]
> 
> Methinks drm_mode_create_lease_ioctl() wants some more arg checking.
> 
> otoh, memdup_user() passes __GFP_NOWARN, so perhaps
> __alloc_frozen_pages_noprof() should be taught to honor that.
> 

A lot of places assume max 32 planes, connectors and crtc's per device.
drm_plane_mask(), drm_connector_mask and drm_crtc_mask are an example.

It wouldn't be too hard to cap it to 96 (or 8 * sizeof(drm_plane_mask(NULL) + ...)
in case it changes. Anything above it will need fixing in a lot of places anyway.

Kind regards,
~Maarten Lankhorst

What about the below?

>>  __do_sys_ioctl fs/ioctl.c:597 [inline]
>>  __se_sys_ioctl fs/ioctl.c:583 [inline]
>>  __arm64_sys_ioctl+0xac/0x104 fs/ioctl.c:583
>>  __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
>>  invoke_syscall+0x54/0x10c arch/arm64/kernel/syscall.c:49
>>  el0_svc_common.constprop.0+0x40/0xe0 arch/arm64/kernel/syscall.c:121
>>  do_el0_svc+0x1c/0x34 arch/arm64/kernel/syscall.c:140
>>  el0_svc+0x38/0x140 arch/arm64/kernel/entry-common.c:740
>>  el0t_64_sync_handler+0xa0/0xf0 arch/arm64/kernel/entry-common.c:759
>>  el0t_64_sync+0x1a4/0x1a8 arch/arm64/kernel/entry.S:594
>> ---[ end trace 0000000000000000 ]---
> 
-- >8 --
There's no practical limit currently to the amount of objects inside the lease ioctl.
Limit it to 96 for now, the maximum of plane_mask + crtc_mask + connector_mask.

I believe this is sufficient on all platforms, and fixes the backtrace below.

------------[ cut here ]------------
WARNING: mm/page_alloc.c:5202 at __alloc_frozen_pages_noprof+0x734/0x1144 mm/page_alloc.c:5202, CPU#0: syz.2.17/3592

	if (WARN_ON_ONCE_GFP(order > MAX_PAGE_ORDER, gfp))

Modules linked in:
CPU: 0 UID: 0 PID: 3592 Comm: syz.2.17 Not tainted syzkaller #0 PREEMPT 
Hardware name: linux,dummy-virt (DT)
pstate: 21402009 (nzCv daif +PAN -UAO -TCO +DIT -SSBS BTYPE=--)
pc : __alloc_frozen_pages_noprof+0x734/0x1144 mm/page_alloc.c:5202
lr : alloc_pages_mpol+0x70/0x1a4 mm/mempolicy.c:2490
sp : ffff800085d93900
x29: ffff800085d93a00 x28: 000000000000000b x27: 0000000000000000
x26: 0000000000000000 x25: fcf0000014c00000 x24: 0000000000040dc0
x23: 0000000000000000 x22: 0000000000000000 x21: 000000000000000b
x20: ffffffffffffffff x19: 0000000000000000 x18: 0000000000000002
x17: 0000000000000000 x16: 0000000000000000 x15: 0000000020000200
x14: ffff8000828b2000 x13: ffffc1ffc0000000 x12: 0000000000000001
x11: 0000000000000000 x10: ffff800082b6f4e8 x9 : 0000000000000000
x8 : 0000000000000030 x7 : ffff800082e9b430 x6 : 0000000000000001
x5 : 0000000000000000 x4 : f3f00000065c90c0 x3 : 0000000000000000
x2 : 0000000000000000 x1 : 0000000000000001 x0 : ffff800082dfd000
Call trace:
 __alloc_frozen_pages_noprof+0x734/0x1144 mm/page_alloc.c:5202 (P)
 alloc_pages_mpol+0x70/0x1a4 mm/mempolicy.c:2490
 alloc_frozen_pages_noprof+0x48/0xd4 mm/mempolicy.c:2561
 ___kmalloc_large_node+0x11c/0x13c mm/slub.c:5237
 __kmalloc_large_node_noprof mm/slub.c:5268 [inline]
 __do_kmalloc_node mm/slub.c:5284 [inline]
 __kmalloc_noprof+0x450/0x560 mm/slub.c:5308
 kmalloc_noprof include/linux/slab.h:954 [inline]
 kzalloc_noprof include/linux/slab.h:1188 [inline]
 fill_object_idr drivers/gpu/drm/drm_lease.c:389 [inline]
 drm_mode_create_lease_ioctl+0x184/0x93c drivers/gpu/drm/drm_lease.c:521
 drm_ioctl_kernel+0xc0/0x130 drivers/gpu/drm/drm_ioctl.c:804
 drm_ioctl+0x258/0x580 drivers/gpu/drm/drm_ioctl.c:901
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:597 [inline]
 __se_sys_ioctl fs/ioctl.c:583 [inline]
 __arm64_sys_ioctl+0xac/0x104 fs/ioctl.c:583
 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
 invoke_syscall+0x54/0x10c arch/arm64/kernel/syscall.c:49
 el0_svc_common.constprop.0+0x40/0xe0 arch/arm64/kernel/syscall.c:121
 do_el0_svc+0x1c/0x34 arch/arm64/kernel/syscall.c:140
 el0_svc+0x38/0x140 arch/arm64/kernel/entry-common.c:740
 el0t_64_sync_handler+0xa0/0xf0 arch/arm64/kernel/entry-common.c:759
 el0t_64_sync+0x1a4/0x1a8 arch/arm64/kernel/entry.S:594
---[ end trace 0000000000000000 ]---

Reported-by: syzbot+5d32c8bd82427f9c77cc@syzkaller.appspotmail.com
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
---
diff --git a/drivers/gpu/drm/drm_lease.c b/drivers/gpu/drm/drm_lease.c
index 5d2cf724cbd7b..9d0ccc8e0274f 100644
--- a/drivers/gpu/drm/drm_lease.c
+++ b/drivers/gpu/drm/drm_lease.c
@@ -486,6 +486,10 @@ int drm_mode_create_lease_ioctl(struct drm_device *dev,
 	struct drm_file *lessee_priv;
 	int fd = -1;
 	uint32_t *object_ids;
+	static const size_t max_objects =
+		8 * sizeof(drm_crtc_mask(NULL)) +
+		8 * sizeof(drm_plane_mask(NULL)) +
+		8 * sizeof(drm_connector_mask(NULL));
 
 	/* Can't lease without MODESET */
 	if (!drm_core_check_feature(dev, DRIVER_MODESET))
@@ -505,6 +509,11 @@ int drm_mode_create_lease_ioctl(struct drm_device *dev,
 	}
 
 	object_count = cl->object_count;
+	if (object_count > max_objects) {
+		drm_dbg_lease(dev, "too many objects (%ld)\n", object_count);
+		ret = -EINVAL;
+		goto out_lessor;
+	}
 
 	/* Handle leased objects, if any */
 	idr_init(&leases);

Re: [PATCH] drm/lease: Limit amount of maximum objects per lease.

[kernel test robot]

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@intel.com/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@intel.com/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@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202605281701.Blefmpwd-lkp@intel.com/

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	

--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki

Re: [PATCH] drm/lease: Limit amount of maximum objects per lease.

[kernel test robot]

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: m68k-allyesconfig (https://download.01.org/0day-ci/archive/20260528/202605281856.LeAMyg6G-lkp@intel.com/config)
compiler: m68k-linux-gcc (GCC) 15.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260528/202605281856.LeAMyg6G-lkp@intel.com/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@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202605281856.LeAMyg6G-lkp@intel.com/

All warnings (new ones prefixed by >>):

   In file included from drivers/gpu/drm/drm_lease.c:13:
   drivers/gpu/drm/drm_lease.c: In function 'drm_mode_create_lease_ioctl':
>> drivers/gpu/drm/drm_lease.c:513:36: warning: format '%ld' expects argument of type 'long int', but argument 5 has type 'size_t' {aka 'unsigned int'} [-Wformat=]
     513 |                 drm_dbg_lease(dev, "too many objects (%ld)\n", object_count);
         |                                    ^~~~~~~~~~~~~~~~~~~~~~~~~~  ~~~~~~~~~~~~
         |                                                                |
         |                                                                size_t {aka unsigned int}
   include/drm/drm_print.h:563:39: note: in definition of macro 'drm_dev_dbg'
     563 |         __drm_dev_dbg(NULL, dev, cat, fmt, ##__VA_ARGS__)
         |                                       ^~~
   drivers/gpu/drm/drm_lease.c:513:17: note: in expansion of macro 'drm_dbg_lease'
     513 |                 drm_dbg_lease(dev, "too many objects (%ld)\n", object_count);
         |                 ^~~~~~~~~~~~~
   drivers/gpu/drm/drm_lease.c:513:57: note: format string is defined here
     513 |                 drm_dbg_lease(dev, "too many objects (%ld)\n", object_count);
         |                                                       ~~^
         |                                                         |
         |                                                         long int
         |                                                       %d


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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https://github.com/intel/lkp-tests/wiki