[LTP] [PATCH] Added new_behavior flag to detect kernel version Kernel >= 6.11: Tests that creat() succeeds (write to executed file allowed)

[Andrea Cervesato]

Hi,

> From: lekshmi-cpillai <lekshmi@ktes.isst.tadn.ibm.com>
> 
> ---
>  testcases/kernel/syscalls/creat/creat07.c | 38 ++++++++++++++++-------
>  1 file changed, 27 insertions(+), 11 deletions(-)
> 
> diff --git a/testcases/kernel/syscalls/creat/creat07.c b/testcases/kernel/syscalls/creat/creat07.c
> index c7b85ee69..762022301 100644
> --- a/testcases/kernel/syscalls/creat/creat07.c
> +++ b/testcases/kernel/syscalls/creat/creat07.c
> @@ -19,6 +19,8 @@
>  
>  #define TEST_APP "creat07_child"
>  
> +static int new_behavior;
> +
>  static void verify_creat(void)
>  {
>  	pid_t pid;
> @@ -33,16 +35,26 @@ static void verify_creat(void)
>  
>  	TEST(creat(TEST_APP, O_WRONLY));
>  
> -	if (TST_RET != -1) {
> -		tst_res(TFAIL, "creat() succeeded unexpectedly");
> -		return;
> +	if (new_behavior) {
> +		/* Kernel >= 6.11: write to executed file is allowed */
> +		if (TST_RET != -1) {
> +			SAFE_CLOSE(TST_RET);
> +			tst_res(TPASS, "creat() succeeded as expected (new behavior)");
> +		} else {
> +			tst_res(TFAIL | TTERRNO, "creat() failed unexpectedly");
> +		}
> +	} else {
> +		/* Kernel < 6.11: write to executed file returns ETXTBSY */
> +		if (TST_RET != -1) {
> +			tst_res(TFAIL, "creat() succeeded unexpectedly");
> +			SAFE_CLOSE(TST_RET);
> +		} else if (TST_ERR == ETXTBSY) {
> +			tst_res(TPASS, "creat() received ETXTBSY");
> +		} else {
> +			tst_res(TFAIL | TTERRNO, "creat() failed unexpectedly");
> +		}
>  	}
>  
> -	if (TST_ERR == ETXTBSY)
> -		tst_res(TPASS, "creat() received EXTBSY");
> -	else
> -		tst_res(TFAIL | TTERRNO, "creat() failed unexpectedly");
> -
>  	SAFE_KILL(pid, SIGKILL);
>  	SAFE_WAITPID(pid, NULL, 0);
>  }
> @@ -50,9 +62,13 @@ static void verify_creat(void)
>  static void setup(void)
>  {
>  	if ((tst_kvercmp(6, 11, 0)) >= 0) {
> -		tst_brk(TCONF, "Skipping test, write to executed file is "
> -			"allowed since 6.11-rc1.\n"
> -			"2a010c412853 (\"fs: don't block i_writecount during exec\")");
> +		new_behavior = 1;
> +		tst_res(TINFO, "Testing new behavior: write to executed file is "
> +			"allowed since 6.11-rc1 (2a010c412853)");
> +	} else {
> +		new_behavior = 0;
> +		tst_res(TINFO, "Testing old behavior: write to executed file "
> +			"returns ETXTBSY");
>  	}
>  }
>  
> -- 
> 2.39.1
> 
> 
> -- 
> Mailing list info: https://lists.linux.it/listinfo/ltp

There's too much going on in these nested statements. The `new_behavior`
is not needed, we only need to save the error code (-1 or ETXTBSY) inside
a static variable.

If it's not -1, TST_EXP_ERR() can be used. Otherwise we print a TPASS.

The kernel version is printed before every test execution, so there's no
need to show any information about it.

Also test it with `-i` parameter. The test is likely broken with this patch.

Kind Regards,
--
Andrea Cervesato
SUSE QE Automation Engineer Linux
andrea.cervesato@suse.com