From 3b3dc052f79731f4a7389b760060928da18823c0 Mon Sep 17 00:00:00 2001 From: Jiang Liu Date: Mon, 6 Jan 2014 14:18:09 +0800 Subject: [PATCH] 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: Yijing Wang Signed-off-by: Jiang Liu Signed-off-by: Joerg Roedel --- drivers/iommu/dmar.c | 14 ++++++++++++-- include/linux/dmar.h | 1 + 2 files changed, 13 insertions(+), 2 deletions(-) diff --git a/drivers/iommu/dmar.c b/drivers/iommu/dmar.c index fb35d1bd19e1..28d93b68ff02 100644 --- a/drivers/iommu/dmar.c +++ b/drivers/iommu/dmar.c @@ -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 diff --git a/include/linux/dmar.h b/include/linux/dmar.h index b029d1aa2d12..8adfce0b32fb 100644 --- a/include/linux/dmar.h +++ b/include/linux/dmar.h @@ -159,6 +159,7 @@ 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 void dmar_free_dev_scope(struct pci_dev ***devices, int *cnt); extern int intel_iommu_init(void); #else /* !CONFIG_INTEL_IOMMU: */ static inline int intel_iommu_init(void) { return -ENODEV; } -- 2.39.5