Commit ada4d4b2 authored by Jiang Liu's avatar Jiang Liu Committed by Joerg Roedel
Browse files

iommu/vt-d: fix PCI device reference leakage on error recovery path 



Function dmar_parse_dev_scope() should release the PCI device reference
count gained in function dmar_parse_one_dev_scope() on error recovery,
otherwise it will cause PCI device object leakage.

This patch also introduces dmar_free_dev_scope(), which will be used
to support DMAR device hotplug.

Reviewed-by: default avatarYijing Wang <wangyijing@huawei.com>
Signed-off-by: default avatarJiang Liu <jiang.liu@linux.intel.com>
Signed-off-by: default avatarJoerg Roedel <joro@8bytes.org>
parent 360eb3c5

drivers/iommu/dmar.c

+12 −2
Original line number Diff line number Diff line
@@ -100,7 +100,6 @@ static int __init dmar_parse_one_dev_scope(struct acpi_dmar_device_scope *scope, 
	if (!pdev) {

		pr_warn("Device scope device [%04x:%02x:%02x.%02x] not found\n",

			segment, scope->bus, path->device, path->function);

		*dev = NULL;

		return 0;

	}

	if ((scope->entry_type == ACPI_DMAR_SCOPE_TYPE_ENDPOINT && \
@@ -151,7 +150,7 @@ int __init dmar_parse_dev_scope(void *start, void *end, int *cnt, 
			ret = dmar_parse_one_dev_scope(scope,

				&(*devices)[index], segment);

			if (ret) {

				kfree(*devices);

				dmar_free_dev_scope(devices, cnt);

				return ret;

			}

			index ++;
@@ -162,6 +161,17 @@ int __init dmar_parse_dev_scope(void *start, void *end, int *cnt, 
	return 0;

}



void dmar_free_dev_scope(struct pci_dev ***devices, int *cnt)

{

	if (*devices && *cnt) {

		while (--*cnt >= 0)

			pci_dev_put((*devices)[*cnt]);

		kfree(*devices);

		*devices = NULL;

		*cnt = 0;

	}

}



/**

 * dmar_parse_one_drhd - parses exactly one DMA remapping hardware definition

 * structure which uniquely represent one DMA remapping hardware unit

include/linux/dmar.h

+3 −2
Original line number Diff line number Diff line
@@ -62,6 +62,9 @@ extern struct list_head dmar_drhd_units; 


extern int dmar_table_init(void);

extern int dmar_dev_scope_init(void);

extern int dmar_parse_dev_scope(void *start, void *end, int *cnt,

				struct pci_dev ***devices, u16 segment);

extern void dmar_free_dev_scope(struct pci_dev ***devices, int *cnt);



/* Intel IOMMU detection */

extern int detect_intel_iommu(void);
@@ -157,8 +160,6 @@ struct dmar_atsr_unit { 
int dmar_parse_rmrr_atsr_dev(void);

extern int dmar_parse_one_rmrr(struct acpi_dmar_header *header);

extern int dmar_parse_one_atsr(struct acpi_dmar_header *header);

extern int dmar_parse_dev_scope(void *start, void *end, int *cnt,

				struct pci_dev ***devices, u16 segment);

extern int intel_iommu_init(void);

#else /* !CONFIG_INTEL_IOMMU: */

static inline int intel_iommu_init(void) { return -ENODEV; }

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