iio: irsd200: fix -Warray-bounds bug in irsd200_trigger_handler

When compiling with gcc 13 with -Warray-bounds enabled:

In file included from drivers/iio/proximity/irsd200.c:15:
In function ‘iio_push_to_buffers_with_timestamp’,
    inlined from ‘irsd200_trigger_handler’ at drivers/iio/proximity/irsd200.c:770:2:
./include/linux/iio/buffer.h:42:46: error: array subscript ‘int64_t {aka long long int}[0]’
is partly outside array bounds of ‘s16[1]’ {aka ‘short int[1]’} [-Werror=array-bounds=]
   42 |                 ((int64_t *)data)[ts_offset] = timestamp;
      |                 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~
drivers/iio/proximity/irsd200.c: In function ‘irsd200_trigger_handler’:
drivers/iio/proximity/irsd200.c:763:13: note: object ‘buf’ of size 2
  763 |         s16 buf = 0;
      |             ^~~

The problem seems to be that irsd200_trigger_handler() is taking a s16
variable as an int64_t buffer. As Jonathan suggested [1], fix it by
extending the buffer to a two-element array of s64.

Link: https://github.com/KSPP/linux/issues/331
Link: https://lore.kernel.org/lkml/20230809181329.46c00a5d@jic23-huawei/
Fixes: 3db3562bc66e ("iio: Add driver for Murata IRS-D200")
Signed-off-by: GONG, Ruiqi <gongruiqi1@huawei.com>
Acked-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Reviewed-by: Waqar Hameed <waqar.hameed@axis.com>
Tested-by: Waqar Hameed <waqar.hameed@axis.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20230810035910.1334706-1-gongruiqi@huaweicloud.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

diff --git a/drivers/iio/proximity/irsd200.c b/drivers/iio/proximity/irsd200.c
index 5bd791b46d98d227b2dbfcfba2ba23dbaf7ddf86..bdff91f6b1a3731178605a9b1c84c43d33d23ecb 100644 (file)
--- a/drivers/iio/proximity/irsd200.c
+++ b/drivers/iio/proximity/irsd200.c
@@ -759,14 +759,14 @@ static irqreturn_t irsd200_trigger_handler(int irq, void *pollf)
 {
        struct iio_dev *indio_dev = ((struct iio_poll_func *)pollf)->indio_dev;
        struct irsd200_data *data = iio_priv(indio_dev);
-       s16 buf = 0;
+       s64 buf[2] = {};
        int ret;
 
-       ret = irsd200_read_data(data, &buf);
+       ret = irsd200_read_data(data, (s16 *)buf);
        if (ret)
                goto end;
 
-       iio_push_to_buffers_with_timestamp(indio_dev, &buf,
+       iio_push_to_buffers_with_timestamp(indio_dev, buf,
                                           iio_get_time_ns(indio_dev));
 
 end: