[PATCH 02/36] x86, PCI: Fix memleak with get_current_resources

Yinghai Lu
2012-03-01T03:01:37Z

in pci_scan_acpi_root, when pci_use_crs is set, get_current_resources is used
to get pci_root_info, and it will allocate name and res array.

later if pci_create_root_bus can not create bus (could be already there...)
it will only free bus res list. but the name and res array is not freed.

let get_current_resource take info pointer instead have local info.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
---
arch/x86/pci/acpi.c | 49 ++++++++++++++++++++++++++++++-------------------
1 files changed, 30 insertions(+), 19 deletions(-)

diff --git a/arch/x86/pci/acpi.c b/arch/x86/pci/acpi.c
index 7cc0a44..304ccf0 100644
--- a/arch/x86/pci/acpi.c
+++ b/arch/x86/pci/acpi.c
@@ -305,49 +305,55 @@ static void add_resources(struct pci_root_info *info)
}
}

+static void free_pci_root_info(struct pci_root_info *info)
+{
+ kfree(info->name);
+ kfree(info->res);
+ memset(info, 0, sizeof(struct pci_root_info));
+}
+
static void
-get_current_resources(struct acpi_device *device, int busnum,
+get_current_resources(struct pci_root_info *info,
+ struct acpi_device *device, int busnum,
int domain, struct list_head *resources)
{
- struct pci_root_info info;
size_t size;

- info.bridge = device;
- info.res_num = 0;
- info.resources = resources;
+ info->bridge = device;
+ info->res_num = 0;
+ info->resources = resources;
acpi_walk_resources(device->handle, METHOD_NAME__CRS, count_resource,
- &info);
- if (!info.res_num)
+ info);
+ if (!info->res_num)
return;

- size = sizeof(*info.res) * info.res_num;
- info.res = kmalloc(size, GFP_KERNEL);
- if (!info.res)
+ size = sizeof(*info->res) * info->res_num;
+ info->res = kmalloc(size, GFP_KERNEL);
+ if (!info->res)
return;

- info.name = kasprintf(GFP_KERNEL, "PCI Bus %04x:%02x", domain, busnum);
- if (!info.name)
+ info->name = kasprintf(GFP_KERNEL, "PCI Bus %04x:%02x", domain, busnum);
+ if (!info->name)
goto name_alloc_fail;

- info.res_num = 0;
+ info->res_num = 0;
acpi_walk_resources(device->handle, METHOD_NAME__CRS, setup_resource,
- &info);
+ info);

if (pci_use_crs) {
- add_resources(&info);
+ add_resources(info);

return;
}

- kfree(info.name);
-
name_alloc_fail:
- kfree(info.res);
+ free_pci_root_info(info);
}

struct pci_bus * __devinit pci_acpi_scan_root(struct acpi_pci_root *root)
{
struct acpi_device *device = root->device;
+ struct pci_root_info info;
int domain = root->segment;
int busnum = root->secondary.start;
LIST_HEAD(resources);
@@ -392,6 +398,7 @@ struct pci_bus * __devinit pci_acpi_scan_root(struct acpi_pci_root *root)

sd->domain = domain;
sd->node = node;
+ memset(&info, 0, sizeof(struct pci_root_info));
/*
* Maybe the desired pci bus has been already scanned. In such case
* it is unnecessary to scan the pci bus with the given domain,busnum.
@@ -405,7 +412,8 @@ struct pci_bus * __devinit pci_acpi_scan_root(struct acpi_pci_root *root)
memcpy(bus->sysdata, sd, sizeof(*sd));
kfree(sd);
} else {
- get_current_resources(device, busnum, domain, &resources);
+ get_current_resources(&info, device, busnum, domain,
+ &resources);

/*
* _CRS with no apertures is normal, so only fall back to
@@ -419,6 +427,9 @@ struct pci_bus * __devinit pci_acpi_scan_root(struct acpi_pci_root *root)
bus->subordinate = pci_scan_child_bus(bus);
else
pci_free_resource_list(&resources);
+
+ if (!bus && pci_use_crs)
+ free_pci_root_info(&info);
}

/* After the PCI-E bus has been walked and all devices discovered,
--
1.7.7