diff mbox series

irqdomain/treewide: Keep firmware node unconditionally allocated

Message ID 873661qakd.fsf@nanos.tec.linutronix.de
State New
Headers show
Series irqdomain/treewide: Keep firmware node unconditionally allocated | expand

Commit Message

Thomas Gleixner July 9, 2020, 9:53 a.m. UTC
Quite some non OF/ACPI users of irqdomains allocate firmware nodes of type
IRQCHIP_FWNODE_NAMED or IRQCHIP_FWNODE_NAMED_ID and free them right after
creating the irqdomain. The only purpose of these FW nodes is to convey
name information. When this was introduced the core code did not store the
pointer to the node in the irqdomain. A recent change stored the firmware
node pointer in irqdomain for other reasons and missed to notice that the
usage sites which do the alloc_fwnode/create_domain/free_fwnode sequence
are broken by this. Storing a dangling pointer is dangerous itself, but in
case that the domain is destroyed later on this leads to a double free.

Remove the freeing of the firmware node after creating the irqdomain from
all affected call sites to cure this.

Fixes: 711419e504eb ("irqdomain: Add the missing assignment of domain->fwnode for named fwnode")
Reported-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org

---
 arch/mips/pci/pci-xtalk-bridge.c    |    5 +++--
 arch/x86/kernel/apic/io_apic.c      |   10 +++++-----
 arch/x86/kernel/apic/msi.c          |   18 ++++++++++++------
 arch/x86/kernel/apic/vector.c       |    1 -
 arch/x86/platform/uv/uv_irq.c       |    3 ++-
 drivers/iommu/amd/iommu.c           |    5 +++--
 drivers/iommu/hyperv-iommu.c        |    5 ++++-
 drivers/iommu/intel/irq_remapping.c |    2 +-
 drivers/mfd/ioc3.c                  |    5 +++--
 drivers/pci/controller/vmd.c        |    5 +++--
 10 files changed, 36 insertions(+), 23 deletions(-)

Comments

Marc Zyngier July 9, 2020, noon UTC | #1
Hi Thomas,

Catching up on email...

On 2020-07-09 10:53, Thomas Gleixner wrote:
> Quite some non OF/ACPI users of irqdomains allocate firmware nodes of 
> type
> IRQCHIP_FWNODE_NAMED or IRQCHIP_FWNODE_NAMED_ID and free them right 
> after
> creating the irqdomain. The only purpose of these FW nodes is to convey
> name information. When this was introduced the core code did not store 
> the
> pointer to the node in the irqdomain. A recent change stored the 
> firmware
> node pointer in irqdomain for other reasons and missed to notice that 
> the
> usage sites which do the alloc_fwnode/create_domain/free_fwnode 
> sequence
> are broken by this. Storing a dangling pointer is dangerous itself, but 
> in
> case that the domain is destroyed later on this leads to a double free.
> 
> Remove the freeing of the firmware node after creating the irqdomain 
> from
> all affected call sites to cure this.
> 
> Fixes: 711419e504eb ("irqdomain: Add the missing assignment of
> domain->fwnode for named fwnode")
> Reported-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
> Cc: stable@vger.kernel.org

Urgh, that's pretty disastrous. My bad. Thanks a lot for having
put this patch together.

Acked-by: Marc Zyngier <maz@kernel.org>

If you can take it directly into Linus' tree, that'd be greatly
appreciated.

Thanks again,

         M.
Bjorn Helgaas July 9, 2020, 9:47 p.m. UTC | #2
On Thu, Jul 09, 2020 at 11:53:06AM +0200, Thomas Gleixner wrote:
> Quite some non OF/ACPI users of irqdomains allocate firmware nodes of type
> IRQCHIP_FWNODE_NAMED or IRQCHIP_FWNODE_NAMED_ID and free them right after
> creating the irqdomain. The only purpose of these FW nodes is to convey
> name information. When this was introduced the core code did not store the
> pointer to the node in the irqdomain. A recent change stored the firmware
> node pointer in irqdomain for other reasons and missed to notice that the
> usage sites which do the alloc_fwnode/create_domain/free_fwnode sequence
> are broken by this. Storing a dangling pointer is dangerous itself, but in
> case that the domain is destroyed later on this leads to a double free.
> 
> Remove the freeing of the firmware node after creating the irqdomain from
> all affected call sites to cure this.
> 
> Fixes: 711419e504eb ("irqdomain: Add the missing assignment of domain->fwnode for named fwnode")
> Reported-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
> Cc: stable@vger.kernel.org

Acked-by: Bjorn Helgaas <bhelgaas@google.com>	# drivers/pci/
diff mbox series

Patch

--- a/arch/mips/pci/pci-xtalk-bridge.c
+++ b/arch/mips/pci/pci-xtalk-bridge.c
@@ -627,9 +627,10 @@  static int bridge_probe(struct platform_
 		return -ENOMEM;
 	domain = irq_domain_create_hierarchy(parent, 0, 8, fn,
 					     &bridge_domain_ops, NULL);
-	irq_domain_free_fwnode(fn);
-	if (!domain)
+	if (!domain) {
+		irq_domain_free_fwnode(fn);
 		return -ENOMEM;
+	}
 
 	pci_set_flags(PCI_PROBE_ONLY);
 
--- a/arch/x86/kernel/apic/io_apic.c
+++ b/arch/x86/kernel/apic/io_apic.c
@@ -2316,12 +2316,12 @@  static int mp_irqdomain_create(int ioapi
 	ip->irqdomain = irq_domain_create_linear(fn, hwirqs, cfg->ops,
 						 (void *)(long)ioapic);
 
-	/* Release fw handle if it was allocated above */
-	if (!cfg->dev)
-		irq_domain_free_fwnode(fn);
-
-	if (!ip->irqdomain)
+	if (!ip->irqdomain) {
+		/* Release fw handle if it was allocated above */
+		if (!cfg->dev)
+			irq_domain_free_fwnode(fn);
 		return -ENOMEM;
+	}
 
 	ip->irqdomain->parent = parent;
 
--- a/arch/x86/kernel/apic/msi.c
+++ b/arch/x86/kernel/apic/msi.c
@@ -263,12 +263,13 @@  void __init arch_init_msi_domain(struct
 		msi_default_domain =
 			pci_msi_create_irq_domain(fn, &pci_msi_domain_info,
 						  parent);
-		irq_domain_free_fwnode(fn);
 	}
-	if (!msi_default_domain)
+	if (!msi_default_domain) {
+		irq_domain_free_fwnode(fn);
 		pr_warn("failed to initialize irqdomain for MSI/MSI-x.\n");
-	else
+	} else {
 		msi_default_domain->flags |= IRQ_DOMAIN_MSI_NOMASK_QUIRK;
+	}
 }
 
 #ifdef CONFIG_IRQ_REMAP
@@ -301,7 +302,8 @@  struct irq_domain *arch_create_remap_msi
 	if (!fn)
 		return NULL;
 	d = pci_msi_create_irq_domain(fn, &pci_msi_ir_domain_info, parent);
-	irq_domain_free_fwnode(fn);
+	if (!d)
+		irq_domain_free_fwnode(fn);
 	return d;
 }
 #endif
@@ -364,7 +366,8 @@  static struct irq_domain *dmar_get_irq_d
 	if (fn) {
 		dmar_domain = msi_create_irq_domain(fn, &dmar_msi_domain_info,
 						    x86_vector_domain);
-		irq_domain_free_fwnode(fn);
+		if (!dmar_domain)
+			irq_domain_free_fwnode(fn);
 	}
 out:
 	mutex_unlock(&dmar_lock);
@@ -489,7 +492,10 @@  struct irq_domain *hpet_create_irq_domai
 	}
 
 	d = msi_create_irq_domain(fn, domain_info, parent);
-	irq_domain_free_fwnode(fn);
+	if (!d) {
+		irq_domain_free_fwnode(fn);
+		kfree(domain_info);
+	}
 	return d;
 }
 
--- a/arch/x86/kernel/apic/vector.c
+++ b/arch/x86/kernel/apic/vector.c
@@ -709,7 +709,6 @@  int __init arch_early_irq_init(void)
 	x86_vector_domain = irq_domain_create_tree(fn, &x86_vector_domain_ops,
 						   NULL);
 	BUG_ON(x86_vector_domain == NULL);
-	irq_domain_free_fwnode(fn);
 	irq_set_default_host(x86_vector_domain);
 
 	arch_init_msi_domain(x86_vector_domain);
--- a/arch/x86/platform/uv/uv_irq.c
+++ b/arch/x86/platform/uv/uv_irq.c
@@ -167,9 +167,10 @@  static struct irq_domain *uv_get_irq_dom
 		goto out;
 
 	uv_domain = irq_domain_create_tree(fn, &uv_domain_ops, NULL);
-	irq_domain_free_fwnode(fn);
 	if (uv_domain)
 		uv_domain->parent = x86_vector_domain;
+	else
+		irq_domain_free_fwnode(fn);
 out:
 	mutex_unlock(&uv_lock);
 
--- a/drivers/iommu/amd/iommu.c
+++ b/drivers/iommu/amd/iommu.c
@@ -3985,9 +3985,10 @@  int amd_iommu_create_irq_domain(struct a
 	if (!fn)
 		return -ENOMEM;
 	iommu->ir_domain = irq_domain_create_tree(fn, &amd_ir_domain_ops, iommu);
-	irq_domain_free_fwnode(fn);
-	if (!iommu->ir_domain)
+	if (!iommu->ir_domain) {
+		irq_domain_free_fwnode(fn);
 		return -ENOMEM;
+	}
 
 	iommu->ir_domain->parent = arch_get_ir_parent_domain();
 	iommu->msi_domain = arch_create_remap_msi_irq_domain(iommu->ir_domain,
--- a/drivers/iommu/hyperv-iommu.c
+++ b/drivers/iommu/hyperv-iommu.c
@@ -155,7 +155,10 @@  static int __init hyperv_prepare_irq_rem
 				0, IOAPIC_REMAPPING_ENTRY, fn,
 				&hyperv_ir_domain_ops, NULL);
 
-	irq_domain_free_fwnode(fn);
+	if (!ioapic_ir_domain) {
+		irq_domain_free_fwnode(fn);
+		return -ENOMEM;
+	}
 
 	/*
 	 * Hyper-V doesn't provide irq remapping function for
--- a/drivers/iommu/intel/irq_remapping.c
+++ b/drivers/iommu/intel/irq_remapping.c
@@ -563,8 +563,8 @@  static int intel_setup_irq_remapping(str
 					    0, INTR_REMAP_TABLE_ENTRIES,
 					    fn, &intel_ir_domain_ops,
 					    iommu);
-	irq_domain_free_fwnode(fn);
 	if (!iommu->ir_domain) {
+		irq_domain_free_fwnode(fn);
 		pr_err("IR%d: failed to allocate irqdomain\n", iommu->seq_id);
 		goto out_free_bitmap;
 	}
--- a/drivers/mfd/ioc3.c
+++ b/drivers/mfd/ioc3.c
@@ -142,10 +142,11 @@  static int ioc3_irq_domain_setup(struct
 		goto err;
 
 	domain = irq_domain_create_linear(fn, 24, &ioc3_irq_domain_ops, ipd);
-	if (!domain)
+	if (!domain) {
+		irq_domain_free_fwnode(fn);
 		goto err;
+	}
 
-	irq_domain_free_fwnode(fn);
 	ipd->domain = domain;
 
 	irq_set_chained_handler_and_data(irq, ioc3_irq_handler, domain);
--- a/drivers/pci/controller/vmd.c
+++ b/drivers/pci/controller/vmd.c
@@ -546,9 +546,10 @@  static int vmd_enable_domain(struct vmd_
 
 	vmd->irq_domain = pci_msi_create_irq_domain(fn, &vmd_msi_domain_info,
 						    x86_vector_domain);
-	irq_domain_free_fwnode(fn);
-	if (!vmd->irq_domain)
+	if (!vmd->irq_domain) {
+		irq_domain_free_fwnode(fn);
 		return -ENODEV;
+	}
 
 	pci_add_resource(&resources, &vmd->resources[0]);
 	pci_add_resource_offset(&resources, &vmd->resources[1], offset[0]);