[LTP] [PATCH v4] readahead02.c: Fix check input fsize

[Cyril Hrubis]

Hi!
> diff --git a/include/tst_device.h b/include/tst_device.h
> index 977427f1c..f03f17f7d 100644
> --- a/include/tst_device.h
> +++ b/include/tst_device.h
> @@ -6,6 +6,8 @@
>  #ifndef TST_DEVICE_H__
>  #define TST_DEVICE_H__
>  
> +#define DEV_SIZE_MB 300u
> +
>  #include <unistd.h>
>  #include <stdint.h>
>  #include <sys/stat.h>
> @@ -49,7 +51,7 @@ int tst_clear_device(const char *dev);
>   * free loopdev). If path is non-NULL, it will be filled with free loopdev path.
>   *
>   */
> -int tst_find_free_loopdev(const char *path, size_t path_len);
> +int tst_find_free_loopdev(char *path, size_t path_len);
>  
>  /*
>   * Attaches a file to a loop device.
> diff --git a/lib/tst_device.c b/lib/tst_device.c
> index 48d7e3ab6..b098fc80b 100644
> --- a/lib/tst_device.c
> +++ b/lib/tst_device.c
> @@ -38,6 +38,7 @@
>  #include "lapi/syscalls.h"
>  #include "test.h"
>  #include "safe_macros.h"
> +#include "tst_device.h"
>  
>  #ifndef LOOP_CTL_GET_FREE
>  # define LOOP_CTL_GET_FREE 0x4C82
> @@ -46,7 +47,6 @@
>  #define LOOP_CONTROL_FILE "/dev/loop-control"
>  
>  #define DEV_FILE "test_dev.img"
> -#define DEV_SIZE_MB 300u
>  #define UUID_STR_SZ 37
>  #define UUID_FMT "%02x%02x%02x%02x-%02x%02x-%02x%02x-%02x%02x-%02x%02x%02x%02x%02x%02x"

These changes are useless now.

> diff --git a/testcases/kernel/syscalls/readahead/readahead02.c b/testcases/kernel/syscalls/readahead/readahead02.c
> index 7acf4bb18..5989c7cbf 100644
> --- a/testcases/kernel/syscalls/readahead/readahead02.c
> +++ b/testcases/kernel/syscalls/readahead/readahead02.c
> @@ -33,6 +33,7 @@
>  #include "tst_test.h"
>  #include "tst_timer.h"
>  #include "lapi/syscalls.h"
> +#include "tst_device.h"
>  
>  static char testfile[PATH_MAX] = "testfile";
>  #define DROP_CACHES_FNAME "/proc/sys/vm/drop_caches"
> @@ -366,11 +367,24 @@ static void setup_readahead_length(void)
>  
>  static void setup(void)
>  {
> -	if (opt_fsizestr) {
> -		testfile_size = SAFE_STRTOL(opt_fsizestr, 1, INT_MAX);
> -		tst_set_max_runtime(1 + testfile_size / (DEFAULT_FILESIZE/32));
> +	/*
> +	 * Acutaly dev size will reduced after create filesystem,
> +	 * so use dev_szie * 0.8 as dev real usage size, test case will
> +	 * create two files within dev so we need div 2 get max file size
> +	 */
> +	size_t fsize_max = tst_device->size * 0.8 / 2 * 1024 * 1024;

I'm not entirely sure about the * 0.8 here. I suppose that we need some
space for metadata and some manipulation space but 20% is probably way
to much. What motivation is behind the exact number here?

> +	/* At least two pagesize for test case */
> +	pagesize = getpagesize();
> +	size_t fsize_min = pagesize * 2;
> +
> +	if (tst_parse_filesize(opt_fsizestr, (long long *)&testfile_size, fsize_min, fsize_max)) {
                                              ^
					      This is wrong, as long as
					      size of size_t and long
					      long is different it will
					      either corrupt memory or
					      crash.

The testfile_size has to be defined long long there is no way around it.

> +		tst_set_max_runtime(1 + DEFAULT_FILESIZE / (DEFAULT_FILESIZE/32));

Why do we even bother with setting runtime if we are doing
tst_brk(TBROK, ...) on the next line?

> +		tst_brk(TBROK, "invalid initial filesize '%s'", opt_fsizestr);
                                             ^
					I do not understand what
					'initial' means in this context.
>  	}
>  
> +	tst_set_max_runtime(1 + testfile_size / (DEFAULT_FILESIZE/32));
> +
>  	if (access(PROC_IO_FNAME, F_OK))
>  		tst_brk(TCONF, "Requires " PROC_IO_FNAME);
>  
> @@ -380,7 +394,6 @@ static void setup(void)
>  	/* check if readahead is supported */
>  	tst_syscall(__NR_readahead, 0, 0, 0);
>  
> -	pagesize = getpagesize();
>  
>  	setup_readahead_length();
>  	tst_res(TINFO, "readahead length: %d", readahead_length);
> -- 
> 2.35.3
> 

-- 
Cyril Hrubis
chrubis@suse.cz