[PATCH v3] ksmbd: don't remove dos attribute xattr on O_TRUNC open

[PATCH v3] ksmbd: don't remove dos attribute xattr on O_TRUNC open

[Namjae Jeon]

When smb client open file in ksmbd share with O_TRUNC, dos attribute
xattr is removed as well as data in file. This cause the FSCTL_SET_SPARSE
request from the client fails because ksmbd can't update the dos attribute
after setting ATTR_SPARSE_FILE. And this patch fix xfstests generic/469
test also.

Fixes: e2f34481b24d ("cifsd: add server-side procedures for SMB3")
Cc: stable@vger.kernel.org
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
---
 v2:
   - don't remove other xattr class also.
   - add fixes and stable tags.
 v3:
   - Change to more simpler check.

 fs/ksmbd/smb2pdu.c | 18 +++++++++---------
 1 file changed, 9 insertions(+), 9 deletions(-)

diff --git a/fs/ksmbd/smb2pdu.c b/fs/ksmbd/smb2pdu.c
index a136d5e4943b..19412ac701a6 100644
--- a/fs/ksmbd/smb2pdu.c
+++ b/fs/ksmbd/smb2pdu.c
@@ -2330,15 +2330,15 @@ static int smb2_remove_smb_xattrs(struct path *path)
 			name += strlen(name) + 1) {
 		ksmbd_debug(SMB, "%s, len %zd\n", name, strlen(name));
 
-		if (strncmp(name, XATTR_USER_PREFIX, XATTR_USER_PREFIX_LEN) &&
-		    strncmp(&name[XATTR_USER_PREFIX_LEN], DOS_ATTRIBUTE_PREFIX,
-			    DOS_ATTRIBUTE_PREFIX_LEN) &&
-		    strncmp(&name[XATTR_USER_PREFIX_LEN], STREAM_PREFIX, STREAM_PREFIX_LEN))
-			continue;
-
-		err = ksmbd_vfs_remove_xattr(user_ns, path->dentry, name);
-		if (err)
-			ksmbd_debug(SMB, "remove xattr failed : %s\n", name);
+		if (!strncmp(name, XATTR_USER_PREFIX, XATTR_USER_PREFIX_LEN) &&
+		    !strncmp(&name[XATTR_USER_PREFIX_LEN], STREAM_PREFIX,
+			     STREAM_PREFIX_LEN)) {
+			err = ksmbd_vfs_remove_xattr(user_ns, path->dentry,
+						     name);
+			if (err)
+				ksmbd_debug(SMB, "remove xattr failed : %s\n",
+					    name);
+		}
 	}
 out:
 	kvfree(xattr_list);
-- 
2.25.1

Re: [PATCH v3] ksmbd: don't remove dos attribute xattr on O_TRUNC open

[Hyunchul Lee]

2022년 8월 14일 (일) 오후 10:53, Namjae Jeon <linkinjeon@kernel.org>님이 작성:
>
> When smb client open file in ksmbd share with O_TRUNC, dos attribute
> xattr is removed as well as data in file. This cause the FSCTL_SET_SPARSE
> request from the client fails because ksmbd can't update the dos attribute
> after setting ATTR_SPARSE_FILE. And this patch fix xfstests generic/469
> test also.
>
> Fixes: e2f34481b24d ("cifsd: add server-side procedures for SMB3")
> Cc: stable@vger.kernel.org
> Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>

Reviewed-by: Hyunchul Lee <hyc.lee@gmail.com>

> ---
>  v2:
>    - don't remove other xattr class also.
>    - add fixes and stable tags.
>  v3:
>    - Change to more simpler check.
>
>  fs/ksmbd/smb2pdu.c | 18 +++++++++---------
>  1 file changed, 9 insertions(+), 9 deletions(-)
>
> diff --git a/fs/ksmbd/smb2pdu.c b/fs/ksmbd/smb2pdu.c
> index a136d5e4943b..19412ac701a6 100644
> --- a/fs/ksmbd/smb2pdu.c
> +++ b/fs/ksmbd/smb2pdu.c
> @@ -2330,15 +2330,15 @@ static int smb2_remove_smb_xattrs(struct path *path)
>                         name += strlen(name) + 1) {
>                 ksmbd_debug(SMB, "%s, len %zd\n", name, strlen(name));
>
> -               if (strncmp(name, XATTR_USER_PREFIX, XATTR_USER_PREFIX_LEN) &&
> -                   strncmp(&name[XATTR_USER_PREFIX_LEN], DOS_ATTRIBUTE_PREFIX,
> -                           DOS_ATTRIBUTE_PREFIX_LEN) &&
> -                   strncmp(&name[XATTR_USER_PREFIX_LEN], STREAM_PREFIX, STREAM_PREFIX_LEN))
> -                       continue;
> -
> -               err = ksmbd_vfs_remove_xattr(user_ns, path->dentry, name);
> -               if (err)
> -                       ksmbd_debug(SMB, "remove xattr failed : %s\n", name);
> +               if (!strncmp(name, XATTR_USER_PREFIX, XATTR_USER_PREFIX_LEN) &&
> +                   !strncmp(&name[XATTR_USER_PREFIX_LEN], STREAM_PREFIX,
> +                            STREAM_PREFIX_LEN)) {
> +                       err = ksmbd_vfs_remove_xattr(user_ns, path->dentry,
> +                                                    name);
> +                       if (err)
> +                               ksmbd_debug(SMB, "remove xattr failed : %s\n",
> +                                           name);
> +               }
>         }
>  out:
>         kvfree(xattr_list);
> --
> 2.25.1
>


-- 
Thanks,
Hyunchul