linux-kernel - Re: [PATCH] iommu/vt-d: fix usage of force parameter in intel_ir_reconfigure

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Date:   Thu, 3 May 2018 14:23:46 +0200
From:   Joerg Roedel <joro@...tes.org>
To:     Jagannathan Raman <jag.raman@...cle.com>
Cc:     tglx@...utronix.de, iommu@...ts.linux-foundation.org,
        linux-kernel@...r.kernel.org
Subject: Re: [PATCH] iommu/vt-d: fix usage of force parameter in
 intel_ir_reconfigure_irte()

On Tue, Mar 06, 2018 at 05:39:41PM -0500, Jagannathan Raman wrote:
> It was noticed that the IRTE configured for guest OS kernel
> was over-written while the guest was running. As a result,
> vt-d Posted Interrupts configured for the guest are not being
> delivered directly, and instead bounces off the host. Every
> interrupt delivery takes a VM Exit.
> 
> It was noticed that the following stack is doing the over-write:
> [  147.463177]  modify_irte+0x171/0x1f0
> [  147.463405]  intel_ir_set_affinity+0x5c/0x80
> [  147.463641]  msi_domain_set_affinity+0x32/0x90
> [  147.463881]  irq_do_set_affinity+0x37/0xd0
> [  147.464125]  irq_set_affinity_locked+0x9d/0xb0
> [  147.464374]  __irq_set_affinity+0x42/0x70
> [  147.464627]  write_irq_affinity.isra.5+0xe1/0x110
> [  147.464895]  proc_reg_write+0x38/0x70
> [  147.465150]  __vfs_write+0x36/0x180
> [  147.465408]  ? handle_mm_fault+0xdf/0x200
> [  147.465671]  ? _cond_resched+0x15/0x30
> [  147.465936]  vfs_write+0xad/0x1a0
> [  147.466204]  SyS_write+0x52/0xc0
> [  147.466472]  do_syscall_64+0x74/0x1a0
> [  147.466744]  entry_SYSCALL_64_after_hwframe+0x3d/0xa2
> 
> reversing the sense of force check in intel_ir_reconfigure_irte()
> restores proper posted interrupt functionality
> 
> Signed-off-by: Jagannathan Raman <jag.raman@...cle.com>

Applie, thanks.