This is a note to let you know that I've just added the patch titled
x86/apic/vector: Handle legacy irq data correctly
to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
x86-apic-vector-handle-legacy-irq-data-correctly.patch
and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From ben.hutchings@xxxxxxxxxxxxxxx Wed Mar 7 11:01:18 2018
From: Ben Hutchings <ben.hutchings@xxxxxxxxxxxxxxx>
Date: Wed, 7 Mar 2018 18:36:43 +0000
Subject: x86/apic/vector: Handle legacy irq data correctly
To: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>, stable@xxxxxxxxxxxxxxx
Message-ID: <20180307183643.7vy7znqgismeh62p@xxxxxxxxxxxxxxxxxxxxxxxxxxx>
Content-Disposition: inline
From: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
The backport of upstream commit 45d55e7bac40 ("x86/apic/vector: Fix off by
one in error path") missed to fixup the legacy interrupt data which is not
longer available upstream.
Handle legacy irq data correctly by clearing the legacy storage to prevent
use after free.
Fixes: 7fd133539289 ("x86/apic/vector: Fix off by one in error path") - 4.4.y
Fixes: c557481a9491 ("x86/apic/vector: Fix off by one in error path") - 4.9.y
Reported-by: Ben Hutchings <ben.hutchings@xxxxxxxxxxxxxxx>
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Signed-off-by: Ben Hutchings <ben.hutchings@xxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
arch/x86/kernel/apic/vector.c | 14 +++++++-------
1 file changed, 7 insertions(+), 7 deletions(-)
--- a/arch/x86/kernel/apic/vector.c
+++ b/arch/x86/kernel/apic/vector.c
@@ -93,8 +93,12 @@ out_data:
return NULL;
}
-static void free_apic_chip_data(struct apic_chip_data *data)
+static void free_apic_chip_data(unsigned int virq, struct apic_chip_data *data)
{
+#ifdef CONFIG_X86_IO_APIC
+ if (virq < nr_legacy_irqs())
+ legacy_irq_data[virq] = NULL;
+#endif
if (data) {
free_cpumask_var(data->domain);
free_cpumask_var(data->old_domain);
@@ -318,11 +322,7 @@ static void x86_vector_free_irqs(struct
apic_data = irq_data->chip_data;
irq_domain_reset_irq_data(irq_data);
raw_spin_unlock_irqrestore(&vector_lock, flags);
- free_apic_chip_data(apic_data);
-#ifdef CONFIG_X86_IO_APIC
- if (virq + i < nr_legacy_irqs())
- legacy_irq_data[virq + i] = NULL;
-#endif
+ free_apic_chip_data(virq + i, apic_data);
}
}
}
@@ -363,7 +363,7 @@ static int x86_vector_alloc_irqs(struct
err = assign_irq_vector_policy(virq + i, node, data, info);
if (err) {
irq_data->chip_data = NULL;
- free_apic_chip_data(data);
+ free_apic_chip_data(virq + i, data);
goto error;
}
}
Patches currently in stable-queue which might be from ben.hutchings@xxxxxxxxxxxxxxx are
queue-4.9/x86-apic-vector-handle-legacy-irq-data-correctly.patch