Re: [PATCH 11/13] smb: introduce struct create_posix_ctxt_rsp

Namjae Jeon
2025-12-09T23:46:12Z

On Tue, Dec 9, 2025 at 10:12 AM <chenxiaosong.chenxiaosong@linux.dev> wrote:
>
> From: ZhangGuoDong <zhangguodong@kylinos.cn>
>
> Modify the following places:
>
> - introduce new struct create_posix_ctxt_rsp
> - some fields in "struct create_posix_rsp" -> "struct create_posix_ctxt_rsp"
> - create_posix_rsp_buf(): offsetof(..., nlink) -> offsetof(..., ctxt_rsp)
I don't know why we need to add a new create_posix_ctxt_rsp struct.
>
> Co-developed-by: ChenXiaoSong <chenxiaosong@kylinos.cn>
> Signed-off-by: ChenXiaoSong <chenxiaosong@kylinos.cn>
> Signed-off-by: ZhangGuoDong <zhangguodong@kylinos.cn>
> ---
> fs/smb/client/smb2pdu.c | 9 +++++----
> fs/smb/client/smb2pdu.h | 6 ++----
> fs/smb/common/smb2pdu.h | 18 ++++++++++++++++++
> fs/smb/server/oplock.c | 8 ++++----
> fs/smb/server/smb2pdu.h | 6 ++----
> 5 files changed, 31 insertions(+), 16 deletions(-)
>
> diff --git a/fs/smb/client/smb2pdu.c b/fs/smb/client/smb2pdu.c
> index ef2c6ac500f7..ec0f83db5591 100644
> --- a/fs/smb/client/smb2pdu.c
> +++ b/fs/smb/client/smb2pdu.c
> @@ -2298,9 +2298,9 @@ parse_posix_ctxt(struct create_context *cc, struct smb2_file_all_info *info,
>
> memset(posix, 0, sizeof(*posix));
>
> - posix->nlink = le32_to_cpu(*(__le32 *)(beg + 0));
> - posix->reparse_tag = le32_to_cpu(*(__le32 *)(beg + 4));
> - posix->mode = le32_to_cpu(*(__le32 *)(beg + 8));
> + posix->ctxt_rsp.nlink = le32_to_cpu(*(__le32 *)(beg + 0));
> + posix->ctxt_rsp.reparse_tag = le32_to_cpu(*(__le32 *)(beg + 4));
> + posix->ctxt_rsp.mode = le32_to_cpu(*(__le32 *)(beg + 8));
>
> sid = beg + 12;
> sid_len = posix_info_sid_size(sid, end);
> @@ -2319,7 +2319,8 @@ parse_posix_ctxt(struct create_context *cc, struct smb2_file_all_info *info,
> memcpy(&posix->group, sid, sid_len);
>
> cifs_dbg(FYI, "nlink=%d mode=%o reparse_tag=%x\n",
> - posix->nlink, posix->mode, posix->reparse_tag);
> + posix->ctxt_rsp.nlink, posix->ctxt_rsp.mode,
> + posix->ctxt_rsp.reparse_tag);
> }
>
> int smb2_parse_contexts(struct TCP_Server_Info *server,
> diff --git a/fs/smb/client/smb2pdu.h b/fs/smb/client/smb2pdu.h
> index 78bb99f29d38..4928fb620233 100644
> --- a/fs/smb/client/smb2pdu.h
> +++ b/fs/smb/client/smb2pdu.h
> @@ -251,11 +251,9 @@ struct smb2_file_id_extd_directory_info {
>
> extern char smb2_padding[7];
>
> -/* equivalent of the contents of SMB3.1.1 POSIX open context response */
> +/* See POSIX-SMB2 2.2.14.2.16 */
> struct create_posix_rsp {
> - u32 nlink;
> - u32 reparse_tag;
> - u32 mode;
> + struct create_posix_ctxt_rsp ctxt_rsp;
> struct smb_sid owner; /* var-sized on the wire */
> struct smb_sid group; /* var-sized on the wire */
> } __packed;
> diff --git a/fs/smb/common/smb2pdu.h b/fs/smb/common/smb2pdu.h
> index 72f2cfc47da8..698ab9d7d16b 100644
> --- a/fs/smb/common/smb2pdu.h
> +++ b/fs/smb/common/smb2pdu.h
> @@ -1814,4 +1814,22 @@ typedef struct smb_negotiate_req {
> unsigned char DialectsArray[];
> } __packed SMB_NEGOTIATE_REQ;
>
> +
> +/*
> + * [POSIX-SMB2] SMB3 POSIX Extensions
> + * Link: https://gitlab.com/samba-team/smb3-posix-spec/-/blob/master/smb3_posix_extensions.md
> + */
> +
> +/*
> + * SMB2_CREATE_POSIX_CONTEXT Response
> + * See POSIX-SMB2 2.2.14.2.16
> + */
> +struct create_posix_ctxt_rsp {
> + __le32 nlink;
> + __le32 reparse_tag;
> + __le32 mode;
> + // var sized owner SID
> + // var sized group SID
> +} __packed;
> +
> #endif /* _COMMON_SMB2PDU_H */
> diff --git a/fs/smb/server/oplock.c b/fs/smb/server/oplock.c
> index 1f07ebf431d7..8658402ff893 100644
> --- a/fs/smb/server/oplock.c
> +++ b/fs/smb/server/oplock.c
> @@ -1703,7 +1703,7 @@ void create_posix_rsp_buf(char *cc, struct ksmbd_file *fp)
> buf = (struct create_posix_rsp *)cc;
> memset(buf, 0, sizeof(struct create_posix_rsp));
> buf->ccontext.DataOffset = cpu_to_le16(offsetof
> - (struct create_posix_rsp, nlink));
> + (struct create_posix_rsp, ctxt_rsp));
> /*
> * DataLength = nlink(4) + reparse_tag(4) + mode(4) +
> * domain sid(28) + unix group sid(16).
> @@ -1730,9 +1730,9 @@ void create_posix_rsp_buf(char *cc, struct ksmbd_file *fp)
> buf->Name[14] = 0xCD;
> buf->Name[15] = 0x7C;
>
> - buf->nlink = cpu_to_le32(inode->i_nlink);
> - buf->reparse_tag = cpu_to_le32(fp->volatile_id);
> - buf->mode = cpu_to_le32(inode->i_mode & 0777);
> + buf->ctxt_rsp.nlink = cpu_to_le32(inode->i_nlink);
> + buf->ctxt_rsp.reparse_tag = cpu_to_le32(fp->volatile_id);
> + buf->ctxt_rsp.mode = cpu_to_le32(inode->i_mode & 0777);
> /*
> * SidBuffer(44) contain two sids(Domain sid(28), UNIX group sid(16)).
> * Domain sid(28) = revision(1) + num_subauth(1) + authority(6) +
> diff --git a/fs/smb/server/smb2pdu.h b/fs/smb/server/smb2pdu.h
> index 66cdc8e4a648..09311a9eb1de 100644
> --- a/fs/smb/server/smb2pdu.h
> +++ b/fs/smb/server/smb2pdu.h
> @@ -83,13 +83,11 @@ struct create_durable_rsp {
> } Data;
> } __packed;
>
> -/* equivalent of the contents of SMB3.1.1 POSIX open context response */
> +/* See POSIX-SMB2 2.2.14.2.16 */
> struct create_posix_rsp {
> struct create_context_hdr ccontext;
> __u8 Name[16];
> - __le32 nlink;
> - __le32 reparse_tag;
> - __le32 mode;
> + struct create_posix_ctxt_rsp ctxt_rsp;
> /* SidBuffer contain two sids(Domain sid(28), UNIX group sid(16)) */
> u8 SidBuffer[44];
> } __packed;
> --
> 2.43.0
>