From a5fe1a03f7720b8da8364a1737e1e5a357904e99 Mon Sep 17 00:00:00 2001 From: Lin Ming Date: Thu, 13 Aug 2009 10:43:27 +0800 Subject: [PATCH] ACPICA: fix leak of acpi_os_validate_address http://bugzilla.kernel.org/show_bug.cgi?id=13620 If the dynamic region is created and added to resource list over and over again, it has the potential to be a memory leak by growing the list every time. This patch fixes the memory leak, as below 1) add a new field "count" to struct acpi_res_list. When inserting, if the region(addr, len) is already in the resource list, we just increase "count", otherwise, the region is inserted with count=1. When deleting, the "count" is decreased, if it's decreased to 0, the region is deleted from the resource list. With "count", the region with same address and length can only be inserted to the resource list once, so prevent potential memory leak. 2) add a new function acpi_os_invalidate_address, which is called when region is deleted. Signed-off-by: Lin Ming Signed-off-by: Len Brown --- drivers/acpi/acpica/utdelete.c | 6 +++ drivers/acpi/osl.c | 94 ++++++++++++++++++++++++++++++++-- include/acpi/acpiosxf.h | 3 ++ 3 files changed, 100 insertions(+), 3 deletions(-) diff --git a/drivers/acpi/acpica/utdelete.c b/drivers/acpi/acpica/utdelete.c index bc1710315088..96e26e70c63d 100644 --- a/drivers/acpi/acpica/utdelete.c +++ b/drivers/acpi/acpica/utdelete.c @@ -215,6 +215,12 @@ static void acpi_ut_delete_internal_obj(union acpi_operand_object *object) ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS, "***** Region %p\n", object)); + /* Invalidate the region address/length via the host OS */ + + acpi_os_invalidate_address(object->region.space_id, + object->region.address, + (acpi_size) object->region.length); + second_desc = acpi_ns_get_secondary_object(object); if (second_desc) { /* diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c index 5691f165a952..c5b4f1ed9b71 100644 --- a/drivers/acpi/osl.c +++ b/drivers/acpi/osl.c @@ -88,6 +88,7 @@ struct acpi_res_list { char name[5]; /* only can have a length of 4 chars, make use of this one instead of res->name, no need to kalloc then */ struct list_head resource_list; + int count; }; static LIST_HEAD(resource_list_head); @@ -1358,6 +1359,89 @@ acpi_os_validate_interface (char *interface) return AE_SUPPORT; } +static inline int acpi_res_list_add(struct acpi_res_list *res) +{ + struct acpi_res_list *res_list_elem; + + list_for_each_entry(res_list_elem, &resource_list_head, + resource_list) { + + if (res->resource_type == res_list_elem->resource_type && + res->start == res_list_elem->start && + res->end == res_list_elem->end) { + + /* + * The Region(addr,len) already exist in the list, + * just increase the count + */ + + res_list_elem->count++; + return 0; + } + } + + res->count = 1; + list_add(&res->resource_list, &resource_list_head); + return 1; +} + +static inline void acpi_res_list_del(struct acpi_res_list *res) +{ + struct acpi_res_list *res_list_elem; + + list_for_each_entry(res_list_elem, &resource_list_head, + resource_list) { + + if (res->resource_type == res_list_elem->resource_type && + res->start == res_list_elem->start && + res->end == res_list_elem->end) { + + /* + * If the res count is decreased to 0, + * remove and free it + */ + + if (--res_list_elem->count == 0) { + list_del(&res_list_elem->resource_list); + kfree(res_list_elem); + } + return; + } + } +} + +acpi_status +acpi_os_invalidate_address( + u8 space_id, + acpi_physical_address address, + acpi_size length) +{ + struct acpi_res_list res; + + switch (space_id) { + case ACPI_ADR_SPACE_SYSTEM_IO: + case ACPI_ADR_SPACE_SYSTEM_MEMORY: + /* Only interference checks against SystemIO and SytemMemory + are needed */ + res.start = address; + res.end = address + length - 1; + res.resource_type = space_id; + spin_lock(&acpi_res_lock); + acpi_res_list_del(&res); + spin_unlock(&acpi_res_lock); + break; + case ACPI_ADR_SPACE_PCI_CONFIG: + case ACPI_ADR_SPACE_EC: + case ACPI_ADR_SPACE_SMBUS: + case ACPI_ADR_SPACE_CMOS: + case ACPI_ADR_SPACE_PCI_BAR_TARGET: + case ACPI_ADR_SPACE_DATA_TABLE: + case ACPI_ADR_SPACE_FIXED_HARDWARE: + break; + } + return AE_OK; +} + /****************************************************************************** * * FUNCTION: acpi_os_validate_address @@ -1382,6 +1466,7 @@ acpi_os_validate_address ( char *name) { struct acpi_res_list *res; + int added; if (acpi_enforce_resources == ENFORCE_RESOURCES_NO) return AE_OK; @@ -1399,14 +1484,17 @@ acpi_os_validate_address ( res->end = address + length - 1; res->resource_type = space_id; spin_lock(&acpi_res_lock); - list_add(&res->resource_list, &resource_list_head); + added = acpi_res_list_add(res); spin_unlock(&acpi_res_lock); - pr_debug("Added %s resource: start: 0x%llx, end: 0x%llx, " - "name: %s\n", (space_id == ACPI_ADR_SPACE_SYSTEM_IO) + pr_debug("%s %s resource: start: 0x%llx, end: 0x%llx, " + "name: %s\n", added ? "Added" : "Already exist", + (space_id == ACPI_ADR_SPACE_SYSTEM_IO) ? "SystemIO" : "System Memory", (unsigned long long)res->start, (unsigned long long)res->end, res->name); + if (!added) + kfree(res); break; case ACPI_ADR_SPACE_PCI_CONFIG: case ACPI_ADR_SPACE_EC: diff --git a/include/acpi/acpiosxf.h b/include/acpi/acpiosxf.h index ab0b85cf21f3..eb0e7189075f 100644 --- a/include/acpi/acpiosxf.h +++ b/include/acpi/acpiosxf.h @@ -245,6 +245,9 @@ acpi_status acpi_osi_invalidate(char* interface); acpi_status acpi_os_validate_address(u8 space_id, acpi_physical_address address, acpi_size length, char *name); +acpi_status +acpi_os_invalidate_address(u8 space_id, acpi_physical_address address, + acpi_size length); u64 acpi_os_get_timer(void);