CVE-2023-52993
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.
Does this matter?
Lower severity and a low EPSS score (0.26%). Track it; it rarely justifies an emergency change on its own.
Description
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.
- CVSS 3.1
- 5.5 MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
- EPSS
- 0.26% probability · 18th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-476
- Affected
- linux/linux kernel
- Source
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
References
- https://git.kernel.org/stable/c/0b08201158f177aab469e356b4d6af24fdd118dfPatch
- https://git.kernel.org/stable/c/137f1b47da5f58805da42c1b7811e28c1e353f39Patch
- https://git.kernel.org/stable/c/496975d1a2937f4baadf3d985991b13fc4fc4f27Patch
- https://git.kernel.org/stable/c/5fa55950729d0762a787451dc52862c3f850f859Patch
- https://git.kernel.org/stable/c/744fe9be9665227335539b7a77ece8d9ff62b6c0Patch
- https://git.kernel.org/stable/c/8770cd9d7c14aa99c255a0d08186f0be953e1638Patch
- https://git.kernel.org/stable/c/e284c273dbb4c1ed68d4204bff94d0b10e4a90f5Patch
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.