Overview
About vulnerability
In the Linux kernel, the following vulnerability has been resolved:
drm/exynos: exynos7_drm_decon: add vblank check in IRQ handling
If there’s support for another console device (such as a TTY serial), the kernel occasionally panics during boot. The panic message and a relevant snippet of the call stack is as follows:
Unable to handle kernel NULL pointer dereference at virtual address 000000000000000 Call trace: drm_crtc_handle_vblank+0x10/0x30 (P) decon_irq_handler+0x88/0xb4 […]
Otherwise, the panics don’t happen. This indicates that it’s some sort of race condition.
Add a check to validate if the drm device can handle vblanks before calling drm_crtc_handle_vblank() to avoid this.
Details
- Affected product:
- AlmaLinux 9.2 ESU , CentOS 8.4 ELS , CentOS 8.5 ELS , CentOS Stream 8 ELS , Oracle Linux 7 ELS , TuxCare 9.6 ESU , Ubuntu 16.04 ELS , Ubuntu 18.04 ELS , Ubuntu 20.04 ELS
- Affected packages:
- kernel @ 5.14.0 (+10 more)
In the Linux kernel, the following vulnerability has been resolved:
drm/exynos: exynos7_drm_decon: add vblank check in IRQ handling
If there’s support for another console device (such as a TTY serial), the kernel occasionally panics during boot. The panic message and a relevant snippet of the call stack is as follows:
Unable to handle kernel NULL pointer dereference at virtual address 000000000000000 Call trace: drm_crtc_handle_vblank+0x10/0x30 (P) decon_irq_handler+0x88/0xb4 […]
Otherwise, the panics don’t happen. This indicates that it’s some sort of race condition.
Add a check to validate if the drm device can handle vblanks before calling drm_crtc_handle_vblank() to avoid this.