Also fix memory leak (buffer.pointer) when returned buffer of length less than 8.
Signed-off-by: Szymon Janc <[email protected]> --- drivers/staging/quickstart/quickstart.c | 38 +++++++++++++++++++++--------- 1 files changed, 26 insertions(+), 12 deletions(-) diff --git a/drivers/staging/quickstart/quickstart.c b/drivers/staging/quickstart/quickstart.c index 7b0deb6..3bae5e7 100644 --- a/drivers/staging/quickstart/quickstart.c +++ b/drivers/staging/quickstart/quickstart.c @@ -191,14 +191,11 @@ static void quickstart_acpi_notify(acpi_handle handle, u32 event, void *data) return; } -static void quickstart_acpi_ghid(struct quickstart_acpi *quickstart) +static int quickstart_acpi_ghid(struct quickstart_acpi *quickstart) { acpi_status status; struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; - uint32_t usageid = 0; - - if (!quickstart) - return; + int ret = 0; /* * This returns a buffer telling the button usage ID, @@ -206,24 +203,41 @@ static void quickstart_acpi_ghid(struct quickstart_acpi *quickstart) */ status = acpi_evaluate_object(quickstart->device->handle, "GHID", NULL, &buffer); - if (ACPI_FAILURE(status) || !buffer.pointer) { + if (ACPI_FAILURE(status)) { printk(KERN_ERR "quickstart: %s GHID method failed.\n", quickstart->btn->name); - return; + return -EINVAL; } - if (buffer.length < 8) - return; - /* * <<The GHID method can return a BYTE, WORD, or DWORD. * The value must be encoded in little-endian byte * order (least significant byte first).>> */ - usageid = *((uint32_t *)(buffer.pointer + (buffer.length - 8))); - quickstart->btn->id = usageid; + switch (buffer.length) { + case 1: + quickstart->btn->id = *(uint8_t *)buffer.pointer; + break; + case 2: + quickstart->btn->id = *(uint16_t *)buffer.pointer; + break; + case 4: + quickstart->btn->id = *(uint32_t *)buffer.pointer; + break; + case 8: + quickstart->btn->id = *(uint64_t *)buffer.pointer; + break; + default: + printk(KERN_ERR "quickstart: %s GHID method returned buffer " + "of unexpected length %u\n", + quickstart->btn->name, buffer.length); + ret = -EINVAL; + break; + } kfree(buffer.pointer); + + return ret; } static int quickstart_acpi_config(struct quickstart_acpi *quickstart, char *bid) -- 1.7.8.3 _______________________________________________ devel mailing list [email protected] http://driverdev.linuxdriverproject.org/mailman/listinfo/devel
