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FAILED: patch "[PATCH] KVM: x86: Refactor picdev_write() to prevent Spectre-v1/L1TF" failed to apply to 4.4-stable tree

PATCH [email protected] 2 participants 2 messages Feb 9, 2020

Subsystems (3)
Stable branch x86 KVM x86
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[email protected]

author maintainer
#0 lore raw

The patch below does not apply to the 4.4-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 14e32321f3606e4b0970200b6e5e47ee6f1e6410 Mon Sep 17 00:00:00 2001
From: Marios Pomonis <[email protected]>
Date: Wed, 11 Dec 2019 12:47:43 -0800
Subject: [PATCH] KVM: x86: Refactor picdev_write() to prevent Spectre-v1/L1TF
attacks

This fixes a Spectre-v1/L1TF vulnerability in picdev_write(). It replaces index computations based on the (attacked-controlled) port number with constants through a minor refactoring.

Fixes 85f455f7ddbe ("KVM: Add support for in-kernel PIC emulation")
Signed-off-by Nick Finco <[email protected]>
Signed-off-by Marios Pomonis <[email protected]>
Reviewed-by Andrew Honig <[email protected]>
Cc [email protected]
Reviewed-by Jim Mattson <[email protected]>
Signed-off-by Paolo Bonzini <[email protected]>
arch/x86/kvm/i8259.c +5 -1
index 8b38bb4868a6..629a09ca9860 100644
@@ -460,10 +460,14 @@ static int picdev_write(struct kvm_pic *s,
 	switch (addr) {
 	case 0x20:
 	case 0x21:
+		pic_lock(s);
+		pic_ioport_write(&s->pics[0], addr, data);
+		pic_unlock(s);
+		break;
 	case 0xa0:
 	case 0xa1:
 		pic_lock(s);
-		pic_ioport_write(&s->pics[addr >> 7], addr, data);
+		pic_ioport_write(&s->pics[1], addr, data);
 		pic_unlock(s);
 		break;
 	case 0x4d0:
maintainer
#1 lore raw
Quoted 22 lines · On Sun, Feb 09, 2020 at 12:54:21PM +0100, [email protected] wrote:

The patch below does not apply to the 4.4-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 14e32321f3606e4b0970200b6e5e47ee6f1e6410 Mon Sep 17 00:00:00 2001
From: Marios Pomonis <[email protected]>
Date: Wed, 11 Dec 2019 12:47:43 -0800
Subject: [PATCH] KVM: x86: Refactor picdev_write() to prevent Spectre-v1/L1TF attacks

This fixes a Spectre-v1/L1TF vulnerability in picdev_write(). It replaces index computations based on the (attacked-controlled) port number with constants through a minor refactoring.

Quoted 8 lines
Fixes 85f455f7ddbe ("KVM: Add support for in-kernel PIC emulation")
Signed-off-by Nick Finco <[email protected]>
Signed-off-by Marios Pomonis <[email protected]>
Reviewed-by Andrew Honig <[email protected]>
Cc [email protected]
Reviewed-by Jim Mattson <[email protected]>
Signed-off-by Paolo Bonzini <[email protected]>

I took in 9fecaa9e32ae ("KVM: x86: drop picdev_in_range()") as a dependency and queued both for 4.4.

Signature · 2 lines
Thanks,
Sasha