On Sunday 06 October 2024 12:00:42 Pali Rohár wrote:
> Native Windows sockets created by WinSock on Windows 10 April 2018 Update
> (version 1803) or Windows Server 2019 (version 1809) or later versions is
> reparse point with IO_REPARSE_TAG_AF_UNIX tag, with empty reparse point
> data buffer and without any EAs.
>
> Create AF_UNIX sockets in this native format when -o reparse=native or
> -o reparse=native+<something> mount option is used.
>
> This change makes AF_UNIX sockets created by Linux CIFS client compatible
> with AF_UNIX sockets created by Windows applications on NTFS volumes.
>
> Signed-off-by: Pali Rohár <pali@xxxxxxxxxx>
> ---
> fs/smb/client/cifsglob.h | 6 +++---
> fs/smb/client/reparse.c | 36 ++++++++++++++++++++++++++++++++++++
> 2 files changed, 39 insertions(+), 3 deletions(-)
>
> diff --git a/fs/smb/client/cifsglob.h b/fs/smb/client/cifsglob.h
> index 7632d2ba5390..570b22d02f7e 100644
> --- a/fs/smb/client/cifsglob.h
> +++ b/fs/smb/client/cifsglob.h
> @@ -155,9 +155,9 @@ enum securityEnum {
>
> enum cifs_reparse_type {
> CIFS_REPARSE_TYPE_NONE, /* disable creating new reparse points */
> - CIFS_REPARSE_TYPE_NATIVE, /* native symlinks only */
> - CIFS_REPARSE_TYPE_NATIVE_NFS, /* native for symlinks, nfs for others */
> - CIFS_REPARSE_TYPE_NATIVE_WSL, /* native for symlinks, wsl for others */
> + CIFS_REPARSE_TYPE_NATIVE, /* native symlinks and sockets only, no support for others */
> + CIFS_REPARSE_TYPE_NATIVE_NFS, /* native for symlinks/sockets, nfs for fifos/block/char */
> + CIFS_REPARSE_TYPE_NATIVE_WSL, /* native for symlinks/sockets, wsl for fifos/block/char */
> CIFS_REPARSE_TYPE_NFS, /* nfs for everything */
> CIFS_REPARSE_TYPE_WSL, /* wsl for everything */
> CIFS_REPARSE_TYPE_DEFAULT = CIFS_REPARSE_TYPE_NATIVE_NFS,
> diff --git a/fs/smb/client/reparse.c b/fs/smb/client/reparse.c
> index 38fe0a710c65..f1488f870320 100644
> --- a/fs/smb/client/reparse.c
> +++ b/fs/smb/client/reparse.c
> @@ -379,6 +379,35 @@ static int detect_directory_symlink_target(struct cifs_sb_info *cifs_sb,
> return 0;
> }
>
> +static int create_native_socket(const unsigned int xid, struct inode *inode,
> + struct dentry *dentry, struct cifs_tcon *tcon,
> + const char *full_path)
> +{
> + struct cifs_open_info_data data = {
> + .reparse_point = true,
> + .reparse = { .tag = IO_REPARSE_TAG_AF_UNIX, },
> + };
> + struct reparse_data_buffer buf = {
> + .ReparseTag = cpu_to_le32(IO_REPARSE_TAG_AF_UNIX),
> + .ReparseDataLength = 0,
Correctly, this should be:
.ReparseDataLength = cpu_to_le16(0),
> + };
> + struct kvec iov = {
> + .iov_base = &buf,
> + .iov_len = sizeof(buf),
> + };
> + struct inode *new;
> + int rc;
Here is missing initialization of rc:
int rc = 0;
> +
> + new = smb2_get_reparse_inode(&data, inode->i_sb, xid,
> + tcon, full_path, false, &iov, NULL);
> + if (!IS_ERR(new))
> + d_instantiate(dentry, new);
> + else
> + rc = PTR_ERR(new);
> + cifs_free_open_info(&data);
> + return rc;
> +}
> +
> static int nfs_set_reparse_buf(struct reparse_posix_data *buf,
> mode_t mode, dev_t dev,
> struct kvec *iov)
> @@ -602,6 +631,13 @@ int smb2_mknod_reparse(unsigned int xid, struct inode *inode,
> {
> struct smb3_fs_context *ctx = CIFS_SB(inode->i_sb)->ctx;
>
> + if (S_ISSOCK(mode) && (
> + ctx->reparse_type == CIFS_REPARSE_TYPE_NATIVE ||
> + ctx->reparse_type == CIFS_REPARSE_TYPE_NATIVE_NFS ||
> + ctx->reparse_type == CIFS_REPARSE_TYPE_NATIVE_WSL)) {
> + return create_native_socket(xid, inode, dentry, tcon, full_path);
> + }
> +
> switch (ctx->reparse_type) {
> case CIFS_REPARSE_TYPE_NATIVE_NFS:
> case CIFS_REPARSE_TYPE_NFS:
> --
> 2.20.1
>
