Re: [PATCH v2] iio: irsd200: fix -Warray-bounds bug in irsd200_trigger_handler

From: Waqar Hameed
Date: Mon Aug 21 2023 - 09:45:59 EST


On Thu, Aug 10, 2023 at 11:59 +0800 "GONG, Ruiqi" <gongruiqi@xxxxxxxxxxxxxxx> wrote:

> From: "GONG, Ruiqi" <gongruiqi1@xxxxxxxxxx>
>
> 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/ [1]
> Fixes: 3db3562bc66e ("iio: Add driver for Murata IRS-D200")
> Signed-off-by: GONG, Ruiqi <gongruiqi1@xxxxxxxxxx>
> Acked-by: Gustavo A. R. Silva <gustavoars@xxxxxxxxxx>

Reviewed-by: Waqar Hameed <waqar.hameed@xxxxxxxx>
Tested-by: Waqar Hameed <waqar.hameed@xxxxxxxx>