oss-security - CVE request: kernel: soft lockup occurs when network load is very high

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Date: Tue, 23 Dec 2008 17:25:13 +0800
From: Eugene Teo <eteo@...hat.com>
To: oss-security@...ts.openwall.com
CC: "Steven M. Christey" <coley@...us.mitre.org>
Subject: CVE request: kernel: soft lockup occurs when network load is very
 high

Steve, can you please assign a CVE name for the following issue:

"[NET]: Add preemption point in qdisc_run

The qdisc_run loop is currently unbounded and runs entirely in a
softirq.  This is bad as it may create an unbounded softirq run.

This patch fixes this by calling need_resched and breaking out if
necessary.

It also adds a break out if the jiffies value changes since that would
indicate we've been transmitting for too long which starves other
softirqs."

Problem is fixed upstream since 2ba2506ca7ca62c56edaa334b0fe61eb5eab6ab0

Reference:
https://bugzilla.redhat.com/show_bug.cgi?id=477744

Reproducer:
https://bugzilla.redhat.com/attachment.cgi?id=327745

This can be triggered by an unprivileged user.

Thanks, Eugene

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