Re: [PATCH] kselftest: arm64: Add a null pointer check

[Muhammad Usama Anjum <usama.anjum@collabora.com>]

On 4/23/24 1:21 PM, Kunwu Chan wrote:
> There is a 'malloc' call, which can be unsuccessful.
> This patch will add the malloc failure checking
> to avoid possible null dereference and give more information
> about test fail reasons.
LGTM

Reviewed-by: Muhammad Usama Anjum <usama.anjum@collabora.com>

> 
> Signed-off-by: Kunwu Chan <chentao@kylinos.cn>
> ---
>  tools/testing/selftests/arm64/tags/tags_test.c | 4 ++++
>  1 file changed, 4 insertions(+)
> 
> diff --git a/tools/testing/selftests/arm64/tags/tags_test.c b/tools/testing/selftests/arm64/tags/tags_test.c
> index 5701163460ef..955f87c1170d 100644
> --- a/tools/testing/selftests/arm64/tags/tags_test.c
> +++ b/tools/testing/selftests/arm64/tags/tags_test.c
> @@ -6,6 +6,7 @@
>  #include <stdint.h>
>  #include <sys/prctl.h>
>  #include <sys/utsname.h>
> +#include "../../kselftest.h"
The test isn't conformed to TAP. Maybe the next patch could be to conform
the whole test into TAP, would be easy and straight forward.

>  
>  #define SHIFT_TAG(tag)		((uint64_t)(tag) << 56)
>  #define SET_TAG(ptr, tag)	(((uint64_t)(ptr) & ~SHIFT_TAG(0xff)) | \
> @@ -21,6 +22,9 @@ int main(void)
>  	if (prctl(PR_SET_TAGGED_ADDR_CTRL, PR_TAGGED_ADDR_ENABLE, 0, 0, 0) == 0)
>  		tbi_enabled = 1;
>  	ptr = (struct utsname *)malloc(sizeof(*ptr));
> +	if (!ptr)
> +		ksft_exit_fail_msg("Failed to allocate utsname buffer\n");
> +
>  	if (tbi_enabled)
>  		tag = 0x42;
>  	ptr = (struct utsname *)SET_TAG(ptr, tag);

-- 
BR,
Muhammad Usama Anjum