Re: [PATCH v1] xfs: correct nlink printf specifier from hd to PRIu32

["Darrick J. Wong" <djwong@kernel.org>]

On Wed, Jul 13, 2022 at 08:57:52PM -0500, Eric Sandeen wrote:
> On 6/28/22 9:45 AM, hexiaole wrote:
> > From: hexiaole <hexiaole@kylinos.cn>
> > 
> > 1. Description
> > libxfs/xfs_log_format.h declare 'di_nlink' as unsigned 32-bit integer:
> > 
> > typedef struct xfs_icdinode {
> >         ...
> >         __uint32_t      di_nlink;       /* number of links to file */
> >         ...
> > } xfs_icdinode_t;
> > 
> > But logprint/log_misc.c use '%hd' to print 'di_nlink':
> > 
> > void
> > xlog_print_trans_inode_core(xfs_icdinode_t *ip)
> > {
> >     ...
> >     printf(_("nlink %hd uid %d gid %d\n"),
> >            ip->di_nlink, ip->di_uid, ip->di_gid);
> >     ...
> > }
> > 
> > '%hd' can be 16-bit on many architectures, on these architectures, the 'printf' only print the low 16-bit of 'di_nlink'.
> > 
> > 2. Reproducer
> > 2.1. Commands
> > [root@localhost ~]# cd
> > [root@localhost ~]# xfs_mkfile 128m 128m.xfs
> > [root@localhost ~]# mkfs.xfs 128m.xfs
> > [root@localhost ~]# mount 128m.xfs /mnt/
> > [root@localhost ~]# cd /mnt/
> > [root@localhost mnt]# seq 1 65534|xargs mkdir -p
> > [root@localhost mnt]# cd
> > [root@localhost ~]# umount /mnt/
> > [root@localhost ~]# xfs_logprint 128m.xfs|grep nlink|tail -1
> > 
> > 2.2. Expect result
> > nlink 65536
> > 
> > 2.3. Actual result
> > nlink 0
> 
> I'm being pedantic for such a small change, but technically this needs to be sent
> with a Signed-off-by: from you please?

It's not pedantry, it's a assertion that the author has the right to
submit the change under the GPL2, which is mandatory.

--D

> It's probably enough for you to just reply to this thread with "yes, please
> add my Signed-off-by"
> 
> Thanks,
> -Eric
> 
> > ---
> >  logprint/log_misc.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> > 
> > diff --git a/logprint/log_misc.c b/logprint/log_misc.c
> > index 35e926a3..6add28ed 100644
> > --- a/logprint/log_misc.c
> > +++ b/logprint/log_misc.c
> > @@ -444,7 +444,7 @@ xlog_print_trans_inode_core(
> >      printf(_("magic 0x%hx mode 0%ho version %d format %d\n"),
> >  	   ip->di_magic, ip->di_mode, (int)ip->di_version,
> >  	   (int)ip->di_format);
> > -    printf(_("nlink %hd uid %d gid %d\n"),
> > +    printf(_("nlink %" PRIu32 " uid %d gid %d\n"),
> >  	   ip->di_nlink, ip->di_uid, ip->di_gid);
> >      printf(_("atime 0x%llx mtime 0x%llx ctime 0x%llx\n"),
> >  		xlog_extract_dinode_ts(ip->di_atime),