oss-sec mailing list archives
Some AMD cpus with RDRAND fail to produce random numbers after suspend/resume
From: Jeffrey Walton <noloader () gmail com>
Date: Thu, 16 Jan 2020 23:21:52 -0500
This just made my radar. It appears some AMD cpus with RDRAND fail to produce random numbers after a suspend/resume. It looks like it was first reported in 2014 or so. Kernel bug: * https://bugzilla.kernel.org/show_bug.cgi?id=85911 Systemd bug: * https://github.com/systemd/systemd/issues/11810 Fedora bug: * https://bugzilla.redhat.com/show_bug.cgi?id=1150286 AMD patch: * https://lore.kernel.org/patchwork/patch/1115413/ I agree with Lennart Poettering. This seems CVE worthy given RDRAND is often used to get the kernel generator (and other userland generators) in good working order. (Thanks to https://www.phoronix.com/scan.php?page=news_item&px=AMD-CPUs-RdRand-Suspend for the article and links).
Current thread:
- Some AMD cpus with RDRAND fail to produce random numbers after suspend/resume Jeffrey Walton (Jan 16)
- Re: Some AMD cpus with RDRAND fail to produce random numbers after suspend/resume Sven Schwedas (Jan 17)
- Re: Some AMD cpus with RDRAND fail to produce random numbers after suspend/resume Peter Kjellström (Jan 20)