IT

Tracker / CVE-2023-52993

CVE-2023-52993

Medium 5.5

In the Linux kernel, the following vulnerability has been resolved: x86/i8259: Mark legacy PIC interrupts with IRQ_LEVEL Baoquan reported that after triggering a crash the subsequent crash-kernel fails to boot about half of the time. It triggers a NULL pointer dereference in the periodic tick code. This happens because the legacy timer interrupt (IRQ0) is resent in software which happens in soft interrupt (tasklet) context. In this context get_irq_regs() returns NULL which leads to the NULL pointer dereference. The reason for the resend is a spurious APIC interrupt on the IRQ0 vector which is captured and leads to a resend when the legacy timer interrupt is enabled. This is wrong because the legacy PIC interrupts are level triggered and therefore should never be resent in software, but nothing ever sets the IRQ_LEVEL flag on those interrupts, so the core code does not know about their trigger type. Ensure that IRQ_LEVEL is set when the legacy PCI interrupts are set up.

Affected products and versions

linux linux_kernel
linux linux_kernel · 2.6.18 → 4.14.305
linux linux_kernel · 4.15 → 4.19.272
linux linux_kernel · 4.20 → 5.4.231
linux linux_kernel · 5.11 → 5.15.91
linux linux_kernel · 5.16 → 6.1.9
linux linux_kernel · 5.5 → 5.10.166

Analysis

This page is not indexable yet.Until it carries original analysis — what it actually exposes, how to check in two minutes whether a system was touched, what to do if it was — the page stays noindex. The database decides that, not the template.

References