From f20aaba9819d0801fb1314363f97239da0100bac Mon Sep 17 00:00:00 2001 From: "Lee, Chun-Yi" Date: Fri, 14 Dec 2012 16:14:26 +0800 Subject: [PATCH] acer-wmi: fix obj is NULL but dereferenced Fengguang Wu run coccinelle and warns about: drivers/platform/x86/acer-wmi.c:1200:17-21: ERROR: obj is NULL but dereferenced. drivers/platform/x86/acer-wmi.c:891:17-21: ERROR: obj is NULL but dereferenced. drivers/platform/x86/acer-wmi.c:1953:17-21: ERROR: obj is NULL but dereferenced. It causes by the code in patch 987dfbaa65b2c3568b85e29d2598da08a011ee09 doesn't check obj variable should not be NULL. There have risk for dereference a NULL obj, so add this patch to fix. Cc: Carlos Corbacho Cc: Matthew Garrett Cc: Dmitry Torokhov Cc: Corentin Chary Cc: Thomas Renninger Signed-off-by: Lee, Chun-Yi Signed-off-by: Matthew Garrett --- drivers/platform/x86/acer-wmi.c | 46 ++++++++++++++++++--------------- 1 file changed, 25 insertions(+), 21 deletions(-) diff --git a/drivers/platform/x86/acer-wmi.c b/drivers/platform/x86/acer-wmi.c index 06f4eb7ab87e..ff0a866791ca 100644 --- a/drivers/platform/x86/acer-wmi.c +++ b/drivers/platform/x86/acer-wmi.c @@ -875,7 +875,7 @@ WMI_execute_u32(u32 method_id, u32 in, u32 *out) struct acpi_buffer input = { (acpi_size) sizeof(u32), (void *)(&in) }; struct acpi_buffer result = { ACPI_ALLOCATE_BUFFER, NULL }; union acpi_object *obj; - u32 tmp; + u32 tmp = 0; acpi_status status; status = wmi_evaluate_method(WMID_GUID1, 1, method_id, &input, &result); @@ -884,14 +884,14 @@ WMI_execute_u32(u32 method_id, u32 in, u32 *out) return status; obj = (union acpi_object *) result.pointer; - if (obj && obj->type == ACPI_TYPE_BUFFER && - (obj->buffer.length == sizeof(u32) || - obj->buffer.length == sizeof(u64))) { - tmp = *((u32 *) obj->buffer.pointer); - } else if (obj->type == ACPI_TYPE_INTEGER) { - tmp = (u32) obj->integer.value; - } else { - tmp = 0; + if (obj) { + if (obj->type == ACPI_TYPE_BUFFER && + (obj->buffer.length == sizeof(u32) || + obj->buffer.length == sizeof(u64))) { + tmp = *((u32 *) obj->buffer.pointer); + } else if (obj->type == ACPI_TYPE_INTEGER) { + tmp = (u32) obj->integer.value; + } } if (out) @@ -1193,12 +1193,14 @@ static acpi_status WMID_set_capabilities(void) return status; obj = (union acpi_object *) out.pointer; - if (obj && obj->type == ACPI_TYPE_BUFFER && - (obj->buffer.length == sizeof(u32) || - obj->buffer.length == sizeof(u64))) { - devices = *((u32 *) obj->buffer.pointer); - } else if (obj->type == ACPI_TYPE_INTEGER) { - devices = (u32) obj->integer.value; + if (obj) { + if (obj->type == ACPI_TYPE_BUFFER && + (obj->buffer.length == sizeof(u32) || + obj->buffer.length == sizeof(u64))) { + devices = *((u32 *) obj->buffer.pointer); + } else if (obj->type == ACPI_TYPE_INTEGER) { + devices = (u32) obj->integer.value; + } } else { kfree(out.pointer); return AE_ERROR; @@ -1946,12 +1948,14 @@ static u32 get_wmid_devices(void) return 0; obj = (union acpi_object *) out.pointer; - if (obj && obj->type == ACPI_TYPE_BUFFER && - (obj->buffer.length == sizeof(u32) || - obj->buffer.length == sizeof(u64))) { - devices = *((u32 *) obj->buffer.pointer); - } else if (obj->type == ACPI_TYPE_INTEGER) { - devices = (u32) obj->integer.value; + if (obj) { + if (obj->type == ACPI_TYPE_BUFFER && + (obj->buffer.length == sizeof(u32) || + obj->buffer.length == sizeof(u64))) { + devices = *((u32 *) obj->buffer.pointer); + } else if (obj->type == ACPI_TYPE_INTEGER) { + devices = (u32) obj->integer.value; + } } kfree(out.pointer); -- 2.39.5