Linux Kernel NULL Pointer Dereference Vulnerability in SCSI Subsystem

A NULL pointer dereference vulnerability has been identified in the Linux kernel's SCSI subsystem, specifically within the 'sd' driver. This issue arises when the 'sd_probe()' function encounters an early error before the 'sdkp->device' is fully initialized. In such cases, the 'sd_zbc_release_disk()' function is called, leading to a NULL pointer dereference when 'sd_is_zoned()' is invoked. The vulnerability has been addressed by removing the problematic call to 'sd_zbc_release_disk()' in the error handling path of 'sd_probe()'. This modification is safe and prevents any memory leakage of zone information, as the zone data for a zoned disk is only allocated when 'sd_revalidate_disk()' is called, ensuring that 'sdkp->disk_dev' is properly set and allowing for the necessary cleanup of disk zone information.

Impact

Exploitation of this vulnerability leads to a NULL pointer dereference, causing a crash of the affected component.