Linux Kernel FBDEV TDFXFB Driver Divide-By-Zero Vulnerability in VSCREENINFO IOCTL

A divide-by-zero vulnerability has been identified in the Linux kernel's FBDEV TDFXFB driver, specifically within the handling of the FBIOPUT_VSCREENINFO ioctl. This issue arises because the driver directly uses the 'pixclock' variable in a division operation, which can lead to a crash if 'pixclock' is zero. The vulnerability affects the stable versions of the Linux kernel.

Impact

Exploitation of this vulnerability causes a kernel crash, leading to a denial of service condition.

Reproduction

The vulnerability can be reproduced by sending an FBIOPUT_VSCREENINFO ioctl command to the TDFXFB driver with a 'pixclock' value of zero. This will trigger the divide-by-zero error, causing a crash.

Remediation

Users can upgrade to the latest stable version of the Linux kernel, where this vulnerability has been addressed.