[LTP] [PATCH] mmap04: Make sure the scanf address format is at least 8 hex chars

[Mark Wielaard]

Hi,

Sorry, I cannot type...

On Thu, 2025-09-18 at 17:26 +0200, Mark Wielaard wrote:
> The addresses in /proc/self/maps are at least 8 hex chars. Zeros are
> added to the front of the address when shorted (both on 32bit and
                                               ^ should be shorter.
> 64bit systems.
               ^ missing closing bracket ).
> 
> Under valgrind the mmaps used in kernel/syscalls/mmap/mmap04.c come
> out very low in the address space and might be shorter than 8 hex
> chars. This causes the scanf to fail:
> mmap04.c:62: TBROK: Expected 1 conversions got 0 FILE '/proc/self/maps'
> 
> Fix this by using "%08" PRIxPTR when creating the fmt used.
> 
> Signed-off-by: Mark Wielaard <mark@klomp.org>
> ---
>  testcases/kernel/syscalls/mmap/mmap04.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/testcases/kernel/syscalls/mmap/mmap04.c b/testcases/kernel/syscalls/mmap/mmap04.c
> index 4a050b7b50da..5b28180df29b 100644
> --- a/testcases/kernel/syscalls/mmap/mmap04.c
> +++ b/testcases/kernel/syscalls/mmap/mmap04.c
> @@ -58,7 +58,8 @@ static void run(unsigned int i)
>  
>  	addr2 = SAFE_MMAP(addr1 + pagesize, pagesize, tc->prot, tc->flags | MAP_FIXED, -1, 0);
>  
> -	sprintf(fmt, "%" PRIxPTR "-%%*x %%s", (uintptr_t)addr2);
> +	/* A /proc/self/maps address is at least 8 hex (left zero padded) */
> +	sprintf(fmt, "%08" PRIxPTR "-%%*x %%s", (uintptr_t)addr2);
>  	SAFE_FILE_LINES_SCANF("/proc/self/maps", fmt, perms);
>  
>  	if (!strcmp(perms, tc->exp_perms)) {