From: Colin Ian King colin.king@canonical.com
[ Upstream commit 98e2630284ab741804bd0713e932e725466f2f84 ]
Currently the kfree of output.pointer can be potentially freeing an uninitalized pointer in the case where out_data is NULL. Fix this by reworking the case where out_data is not-null to perform the ACPI status check and also the kfree of outpoint.pointer in one block and hence ensuring the pointer is only freed when it has been used.
Also replace the if (ptr != NULL) idiom with just if (ptr).
Fixes: ff0e9f26288d ("platform/x86: alienware-wmi: Correct a memory leak") Signed-off-by: Colin Ian King colin.king@canonical.com Signed-off-by: Darren Hart (VMware) dvhart@infradead.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/platform/x86/alienware-wmi.c | 17 ++++++++--------- 1 file changed, 8 insertions(+), 9 deletions(-)
diff --git a/drivers/platform/x86/alienware-wmi.c b/drivers/platform/x86/alienware-wmi.c index f10af5c383c5..c0d1555735cd 100644 --- a/drivers/platform/x86/alienware-wmi.c +++ b/drivers/platform/x86/alienware-wmi.c @@ -522,23 +522,22 @@ static acpi_status alienware_wmax_command(struct wmax_basic_args *in_args,
input.length = (acpi_size) sizeof(*in_args); input.pointer = in_args; - if (out_data != NULL) { + if (out_data) { output.length = ACPI_ALLOCATE_BUFFER; output.pointer = NULL; status = wmi_evaluate_method(WMAX_CONTROL_GUID, 0, command, &input, &output); - } else + if (ACPI_SUCCESS(status)) { + obj = (union acpi_object *)output.pointer; + if (obj && obj->type == ACPI_TYPE_INTEGER) + *out_data = (u32)obj->integer.value; + } + kfree(output.pointer); + } else { status = wmi_evaluate_method(WMAX_CONTROL_GUID, 0, command, &input, NULL); - - if (ACPI_SUCCESS(status) && out_data != NULL) { - obj = (union acpi_object *)output.pointer; - if (obj && obj->type == ACPI_TYPE_INTEGER) - *out_data = (u32) obj->integer.value; } - kfree(output.pointer); return status; - }
/*