[PATCH 4.9 81/84] ACPI: ioapic: Clear on-stack resource before using it

[Greg Kroah-Hartman]

4.9-stable review patch.  If anyone has any objections, please let me know.

--

From: Joerg Roedel 

commit e3d5092b6756b9e0b08f94bbeafcc7afe19f0996 upstream.

The on-stack resource-window 'win' in setup_res() is not
properly initialized. This causes the pointers in the
embedded 'struct resource' to contain stale addresses.

These pointers (in my case the ->child pointer) later get
propagated to the global iomem_resources list, causing a #GP
exception when the list is traversed in
iomem_map_sanity_check().

Fixes: c183619b63ec (x86/irq, ACPI: Implement ACPI driver to support IOAPIC 
hotplug)
Signed-off-by: Joerg Roedel 
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Greg Kroah-Hartman 

---
 drivers/acpi/ioapic.c |6 ++
 1 file changed, 6 insertions(+)

--- a/drivers/acpi/ioapic.c
+++ b/drivers/acpi/ioapic.c
@@ -45,6 +45,12 @@ static acpi_status setup_res(struct acpi
struct resource *res = data;
struct resource_win win;
 
+   /*
+* We might assign this to 'res' later, make sure all pointers are
+* cleared before the resource is added to the global list
+*/
+   memset(, 0, sizeof(win));
+
res->flags = 0;
if (acpi_dev_filter_resource_type(acpi_res, IORESOURCE_MEM))
return AE_OK;

[PATCH 4.9 81/84] ACPI: ioapic: Clear on-stack resource before using it

[Greg Kroah-Hartman]

4.9-stable review patch.  If anyone has any objections, please let me know.

--

From: Joerg Roedel 

commit e3d5092b6756b9e0b08f94bbeafcc7afe19f0996 upstream.

The on-stack resource-window 'win' in setup_res() is not
properly initialized. This causes the pointers in the
embedded 'struct resource' to contain stale addresses.

These pointers (in my case the ->child pointer) later get
propagated to the global iomem_resources list, causing a #GP
exception when the list is traversed in
iomem_map_sanity_check().

Fixes: c183619b63ec (x86/irq, ACPI: Implement ACPI driver to support IOAPIC 
hotplug)
Signed-off-by: Joerg Roedel 
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Greg Kroah-Hartman 

---
 drivers/acpi/ioapic.c |6 ++
 1 file changed, 6 insertions(+)

--- a/drivers/acpi/ioapic.c
+++ b/drivers/acpi/ioapic.c
@@ -45,6 +45,12 @@ static acpi_status setup_res(struct acpi
struct resource *res = data;
struct resource_win win;
 
+   /*
+* We might assign this to 'res' later, make sure all pointers are
+* cleared before the resource is added to the global list
+*/
+   memset(, 0, sizeof(win));
+
res->flags = 0;
if (acpi_dev_filter_resource_type(acpi_res, IORESOURCE_MEM))
return AE_OK;