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 4.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git%3Ba=su...
The filename of the patch is: x86-apic-vector-handle-legacy-irq-data-correctly.patch and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree, please let stable@vger.kernel.org know about it.
From ben.hutchings@codethink.co.uk Wed Mar 7 11:01:18 2018
From: Ben Hutchings ben.hutchings@codethink.co.uk Date: Wed, 7 Mar 2018 18:36:43 +0000 Subject: x86/apic/vector: Handle legacy irq data correctly To: Greg Kroah-Hartman gregkh@linuxfoundation.org Cc: Thomas Gleixner tglx@linutronix.de, stable@vger.kernel.org Message-ID: 20180307183643.7vy7znqgismeh62p@xylophone.i.decadent.org.uk Content-Disposition: inline
From: Thomas Gleixner tglx@linutronix.de
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@codethink.co.uk Signed-off-by: Thomas Gleixner tglx@linutronix.de Signed-off-by: Ben Hutchings ben.hutchings@codethink.co.uk Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- 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 @@ -91,8 +91,12 @@ 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); @@ -316,11 +320,7 @@ 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); } } } @@ -361,7 +361,7 @@ 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@codethink.co.uk are
queue-4.4/x86-apic-vector-handle-legacy-irq-data-correctly.patch