Re: [PATCH] chattr: add maximum value check for project

["Darrick J. Wong" <darrick.wong@oracle.com>]

On Wed, Sep 27, 2017 at 12:21:15PM +0800, Wang Shilong wrote:
> From: Wang Shilong <wshilong@ddn.com>
> 
> See following output:
> [root@mds03 client]# chattr -R +P -p 4294967296 testdir/
> [root@mds03 client]# lsattr -dp testdir/
>     0 ----------------P testdir/
> [root@mds03 client]# chattr -R +P -p 4294967297 testdir/
> [root@mds03 client]# lsattr -dp testdir/
>     1 ----------------P testdir/
> 
> Reported-by: Shuichi Ihara <sihara@ddn.com>
> Signed-off-by: Wang Shilong <wshilong@ddn.com>
> ---
>  lib/ext2fs/ext2_fs.h |  2 ++
>  misc/chattr.c        | 11 ++++++++---
>  misc/mke2fs.c        |  2 --
>  3 files changed, 10 insertions(+), 5 deletions(-)
> 
> diff --git a/lib/ext2fs/ext2_fs.h b/lib/ext2fs/ext2_fs.h
> index 3b55000..99f89ec 100644
> --- a/lib/ext2fs/ext2_fs.h
> +++ b/lib/ext2fs/ext2_fs.h
> @@ -75,6 +75,8 @@
>   */
>  #define EXT2_LINK_MAX		65000
>  
> +#define MAX_32_NUM ((((unsigned long long) 1) << 32) - 1)

Is UINT32_MAX insufficient for these uses?

Also, this whole section of decode_arg mixes types... project is
'unsigned long', MAX_32_NUM is 'unsigned long long', and strtol returns
'long'.  Can we pick one and stick with it?

--D

> +
>  /*
>   * Macro-instructions used to manage several block sizes
>   */
> diff --git a/misc/chattr.c b/misc/chattr.c
> index a5b401a..bab20e8 100644
> --- a/misc/chattr.c
> +++ b/misc/chattr.c
> @@ -152,13 +152,18 @@ static int decode_arg (int * i, int argc, char ** argv)
>  			if (*p == 'p') {
>  				(*i)++;
>  				if (*i >= argc)
> -					usage ();
> -				project = strtol (argv[*i], &tmp, 0);
> +					usage();
> +				project = strtol(argv[*i], &tmp, 0);
>  				if (*tmp) {
>  					com_err (program_name, 0,
>  						 _("bad project - %s\n"),
>  						 argv[*i]);
> -					usage ();
> +					usage();
> +				}
> +				if (project > MAX_32_NUM) {
> +					com_err(program_name, 0,
> +						_("Kernel does not support set project ID this large"));
> +					exit(1);
>  				}
>  				set_project = 1;
>  				continue;
> diff --git a/misc/mke2fs.c b/misc/mke2fs.c
> index d585a9e..22812cd 100644
> --- a/misc/mke2fs.c
> +++ b/misc/mke2fs.c
> @@ -63,8 +63,6 @@ extern int optind;
>  
>  #define STRIDE_LENGTH 8
>  
> -#define MAX_32_NUM ((((unsigned long long) 1) << 32) - 1)
> -
>  #ifndef __sparc__
>  #define ZAP_BOOTBLOCK
>  #endif
> -- 
> 1.8.3.1
>