CVE-2021-47471: drm: mxsfb: Fix NULL pointer dereference crash on unload

Severity: medium (CVSS 5.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2024-05-22 · updated 2026-06-17
Weakness: CWE-476

Description

In the Linux kernel, the following vulnerability has been resolved: drm: mxsfb: Fix NULL pointer dereference crash on unload The mxsfb->crtc.funcs may already be NULL when unloading the driver, in which case calling mxsfb_irq_disable() via drm_irq_uninstall() from mxsfb_unload() leads to NULL pointer dereference. Since all we care about is masking the IRQ and mxsfb->base is still valid, just use that to clear and mask the IRQ.

Affected products

Linux kernel: from 5.10 before 5.10.76; from 5.11 before 5.14.15; 5.15-rc1, 5.15-rc2, 5.15-rc3, 5.15-rc4, 5.15-rc5, 5.15-rc6 — fixed in 5.10.76, 5.14.15

How to fix

Upgrade to a fixed version: Linux kernel 5.10.76, 5.14.15. Check the vendor advisory for mitigations.

References

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