# CVE-2022-48633: drm/gma500: Fix WARN_ON(lock->magic != lock) error

> A use-after-free condition in the gma500 DRM driver can cause a kernel warning and potential system crash when releasing graphics objects.

- **Severity:** Medium 5.5 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 28 Apr 2024
- **Updated:** 12 Aug 2026
- **Also known as:** DEBIAN-CVE-2022-48633, GHSA-9939-379m-g97w, ROOT-OS-DEBIAN-11-CVE-2022-48633, ROOT-OS-UBUNTU-2204-CVE-2022-48633, UBUNTU-CVE-2022-48633

## What is CVE-2022-48633?

CVE-2022-48633 is a medium-severity vulnerability in Linux kernel, published on 28 Apr 2024. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

In the Linux kernel, the following vulnerability has been resolved:

drm/gma500: Fix WARN_ON(lock->magic != lock) error

psb_gem_unpin() calls dma_resv_lock() but the underlying ww_mutex
gets destroyed by drm_gem_object_release() move the
drm_gem_object_release() call in psb_gem_free_object() to after
the unpin to fix the below warning:

[   79.693962] ------------[ cut here ]------------
[   79.693992] DEBUG_LOCKS_WARN_ON(lock->magic != lock)
[   79.694015] WARNING: CPU: 0 PID: 240 at kernel/locking/mutex.c:582 __ww_mutex_lock.constprop.0+0x569/0xfb0
[   79.694052] Modules linked in: rfcomm snd_seq_dummy snd_hrtimer qrtr bnep ath9k ath9k_common ath9k_hw snd_hda_codec_realtek snd_hda_codec_generic ledtrig_audio snd_hda_codec_hdmi snd_hda_intel ath3k snd_intel_dspcfg mac80211 snd_intel_sdw_acpi btusb snd_hda_codec btrtl btbcm btintel btmtk bluetooth at24 snd_hda_core snd_hwdep uvcvideo snd_seq libarc4 videobuf2_vmalloc ath videobuf2_memops videobuf2_v4l2 videobuf2_common snd_seq_device videodev acer_wmi intel_powerclamp coretemp mc snd_pcm joydev sparse_keymap ecdh_generic pcspkr wmi_bmof cfg80211 i2c_i801 i2c_smbus snd_timer snd r8169 rfkill lpc_ich soundcore acpi_cpufreq zram rtsx_pci_sdmmc mmc_core serio_raw rtsx_pci gma500_gfx(E) video wmi ip6_tables ip_tables i2c_dev fuse
[   79.694436] CPU: 0 PID: 240 Comm: plymouthd Tainted: G        W   E      6.0.0-rc3+ #490
[   79.694457] Hardware name: Packard Bell dot s/SJE01_CT, BIOS V1.10 07/23/2013
[   79.694469] RIP: 0010:__ww_mutex_lock.constprop.0+0x569/0xfb0
[   79.694496] Code: ff 85 c0 0f 84 15 fb ff ff 8b 05 ca 3c 11 01 85 c0 0f 85 07 fb ff ff 48 c7 c6 30 cb 84 aa 48 c7 c7 a3 e1 82 aa e8 ac 29 f8 ff <0f> 0b e9 ed fa ff ff e8 5b 83 8a ff 85 c0 74 10 44 8b 0d 98 3c 11
[   79.694513] RSP: 0018:ffffad1dc048bbe0 EFLAGS: 00010282
[   79.694623] RAX: 0000000000000028 RBX: 0000000000000000 RCX: 0000000000000000
[   79.694636] RDX: 0000000000000001 RSI: ffffffffaa8b0ffc RDI: 00000000ffffffff
[   79.694650] RBP: ffffad1dc048bc80 R08: 0000000000000000 R09: ffffad1dc048ba90
[   79.694662] R10: 0000000000000003 R11: ffffffffaad62fe8 R12: ffff9ff302103138
[   79.694675] R13: ffff9ff306ec8000 R14: ffff9ff307779078 R15: ffff9ff3014c0270
[   79.694690] FS:  00007ff1cccf1740(0000) GS:ffff9ff3bc200000(0000) knlGS:0000000000000000
[   79.694705] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   79.694719] CR2: 0000559ecbcb4420 CR3: 0000000013210000 CR4: 00000000000006f0
[   79.694734] Call Trace:
[   79.694749]  <TASK>
[   79.694761]  ? __schedule+0x47f/0x1670
[   79.694796]  ? psb_gem_unpin+0x27/0x1a0 [gma500_gfx]
[   79.694830]  ? lock_is_held_type+0xe3/0x140
[   79.694864]  ? ww_mutex_lock+0x38/0xa0
[   79.694885]  ? __cond_resched+0x1c/0x30
[   79.694902]  ww_mutex_lock+0x38/0xa0
[   79.694925]  psb_gem_unpin+0x27/0x1a0 [gma500_gfx]
[   79.694964]  psb_gem_unpin+0x199/0x1a0 [gma500_gfx]
[   79.694996]  drm_gem_object_release_handle+0x50/0x60
[   79.695020]  ? drm_gem_object_handle_put_unlocked+0xf0/0xf0
[   79.695042]  idr_for_each+0x4b/0xb0
[   79.695066]  ? _raw_spin_unlock_irqrestore+0x30/0x60
[   79.695095]  drm_gem_release+0x1c/0x30
[   79.695118]  drm_file_free.part.0+0x1ea/0x260
[   79.695150]  drm_release+0x6a/0x120
[   79.695175]  __fput+0x9f/0x260
[   79.695203]  task_work_run+0x59/0xa0
[   79.695227]  do_exit+0x387/0xbe0
[   79.695250]  ? seqcount_lockdep_reader_access.constprop.0+0x82/0x90
[   79.695275]  ? lockdep_hardirqs_on+0x7d/0x100
[   79.695304]  do_group_exit+0x33/0xb0
[   79.695331]  __x64_sys_exit_group+0x14/0x20
[   79.695353]  do_syscall_64+0x58/0x80
[   79.695376]  ? up_read+0x17/0x20
[   79.695401]  ? lock_is_held_type+0xe3/0x140
[   79.695429]  ? asm_exc_page_fault+0x22/0x30
[   79.695450]  ? lockdep_hardirqs_on+0x7d/0x100
[   79.695473]  entry_SYSCALL_64_after_hwframe+0x63/0xcd
[   79.695493] RIP: 0033:0x7ff1ccefe3f1
[   79.695516] Code: Unable to access opcode bytes at RIP 0x7ff1ccefe3c7.
[   79.695607] RSP: 002b:00007ffed4413378 EFLAGS: 
---truncated---

Weakness: CWE-617 (Reachable Assertion)

## Which versions are affected by CVE-2022-48633?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2022-48633?

Apply the vendor's patch.

## Is CVE-2022-48633 being exploited?

There is no known exploitation of CVE-2022-48633 in the wild and no public exploit code.

## Other vulnerabilities in Linux kernel

- [CVE-2026-53266](https://insights.sbomify.com/CVE-2026-53266/): Linux Kernel Out-of-Bounds Write (high 8.8, exploited in the wild)
- [CVE-2013-6282](https://insights.sbomify.com/CVE-2013-6282/): Linux Kernel Improper Input Validation (high 8.8, exploited in the wild)
- [CVE-2022-0185](https://insights.sbomify.com/CVE-2022-0185/): Linux Kernel Heap-Based Buffer Overflow (high 8.4, exploited in the wild)
- [CVE-2013-2094](https://insights.sbomify.com/CVE-2013-2094/): Linux Kernel Privilege Escalation (high 8.4, exploited in the wild)
- [CVE-2026-53362](https://insights.sbomify.com/CVE-2026-53362/): Linux Kernel Unspecified (high 7.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2022-48633 and fix it if it is affected.

What it is: CVE-2022-48633 is a medium-severity vulnerability in Linux kernel, published on 28 Apr 2024. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2022-48633 in the wild and no public exploit code.

Affected product: Linux kernel. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2022-48633/ (Markdown: https://insights.sbomify.com/CVE-2022-48633/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2022-48633
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2022-48633
- OSV: https://osv.dev/vulnerability/CVE-2022-48633

---
From sbomify Insights: https://insights.sbomify.com/CVE-2022-48633/
Summaries are generated and may contain mistakes; the official description above is the record.
