linux-fsdevel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Al Viro <viro@zeniv.linux.org.uk>
To: Miklos Szeredi <mszeredi@redhat.com>
Cc: linux-fsdevel@vger.kernel.org
Subject: Re: [PATCH 09/12] fs_parser: "string" with missing value is a "flag"
Date: Tue, 17 Dec 2019 17:32:59 +0000	[thread overview]
Message-ID: <20191217173259.GA4203@ZenIV.linux.org.uk> (raw)
In-Reply-To: <20191128155940.17530-10-mszeredi@redhat.com>

On Thu, Nov 28, 2019 at 04:59:37PM +0100, Miklos Szeredi wrote:
> There's no such thing as a NULL string value, the fsconfig(2) syscall
> rejects that outright.
> 
> So get rid of that concept from the implementation.
> 
> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
> ---
>  fs/fs_context.c           | 2 +-
>  fs/fs_parser.c            | 9 ++-------
>  include/linux/fs_parser.h | 1 -
>  3 files changed, 3 insertions(+), 9 deletions(-)
> 
> diff --git a/fs/fs_context.c b/fs/fs_context.c
> index 66fd7d753e91..7c4216156950 100644
> --- a/fs/fs_context.c
> +++ b/fs/fs_context.c
> @@ -174,7 +174,7 @@ int vfs_parse_fs_string(struct fs_context *fc, const char *key,
>  
>  	struct fs_parameter param = {
>  		.key	= key,
> -		.type	= fs_value_is_string,
> +		.type	= v_size ? fs_value_is_string : fs_value_is_flag,
>  		.size	= v_size,
>  	};

No.  This is simply wrong - as it is, there's no difference between
"foo" and "foo=".  Passing NULL in the latter case is wrong, but
this is not a good fix.

This
        if (v_size > 0) {
                param.string = kmemdup_nul(value, v_size, GFP_KERNEL);
                if (!param.string)
                        return -ENOMEM;
        }
should really be
	if (value) {
                param.string = kmemdup_nul(value, v_size, GFP_KERNEL);
                if (!param.string)
                        return -ENOMEM;
        }
and your chunk should be conditional upon value, not v_size.  The
same problem exists for rbd.c

  reply	other threads:[~2019-12-17 17:33 UTC|newest]

Thread overview: 37+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-11-28 15:59 [PATCH 00/12] various vfs patches Miklos Szeredi
2019-11-28 15:59 ` [PATCH 01/12] aio: fix async fsync creds Miklos Szeredi
2019-12-13  9:32   ` Miklos Szeredi
2020-05-04  8:05   ` Avi Kivity
2019-11-28 15:59 ` [PATCH 02/12] fs_parse: fix fs_param_v_optional handling Miklos Szeredi
2019-11-29 11:31   ` Andrew Price
2019-11-29 14:43     ` Miklos Szeredi
2019-11-29 15:56       ` Andrew Price
2019-12-16 23:28   ` Al Viro
2019-12-17  1:18     ` Al Viro
2019-12-17  3:27       ` Al Viro
2019-11-28 15:59 ` [PATCH 03/12] vfs: verify param type in vfs_parse_sb_flag() Miklos Szeredi
2019-11-28 15:59 ` [PATCH 04/12] uapi: deprecate STATX_ALL Miklos Szeredi
2019-11-28 15:59 ` [PATCH 05/12] statx: don't clear STATX_ATIME on SB_RDONLY Miklos Szeredi
2019-11-28 15:59 ` [PATCH 06/12] utimensat: AT_EMPTY_PATH support Miklos Szeredi
2019-11-28 15:59 ` [PATCH 07/12] f*xattr: allow O_PATH descriptors Miklos Szeredi
2019-11-28 15:59 ` [PATCH 08/12] vfs: allow unprivileged whiteout creation Miklos Szeredi
2019-12-17  3:51   ` Al Viro
2019-12-17  4:22     ` Miklos Szeredi
2019-11-28 15:59 ` [PATCH 09/12] fs_parser: "string" with missing value is a "flag" Miklos Szeredi
2019-12-17 17:32   ` Al Viro [this message]
2019-12-17 18:31     ` Al Viro
2019-11-28 15:59 ` [PATCH 10/12] vfs: don't parse forbidden flags Miklos Szeredi
2019-11-28 15:59 ` [PATCH 11/12] vfs: don't parse "posixacl" option Miklos Szeredi
2019-12-17  3:42   ` Al Viro
2019-12-17  4:18     ` Miklos Szeredi
2019-12-17  4:28       ` Al Viro
2019-11-28 15:59 ` [PATCH 12/12] vfs: don't parse "silent" option Miklos Szeredi
2019-12-17  3:37   ` Al Viro
2019-12-17  4:12     ` Miklos Szeredi
2019-12-17  4:16       ` Miklos Szeredi
2019-12-17  4:19         ` Al Viro
2019-12-17  4:23           ` Miklos Szeredi
2019-12-17  4:28             ` Miklos Szeredi
2019-12-17  4:17       ` Al Viro
2019-12-13  9:33 ` [PATCH 00/12] various vfs patches Miklos Szeredi
2019-12-16 23:13   ` Al Viro

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20191217173259.GA4203@ZenIV.linux.org.uk \
    --to=viro@zeniv.linux.org.uk \
    --cc=linux-fsdevel@vger.kernel.org \
    --cc=mszeredi@redhat.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).