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,
+ };
+ struct kvec iov = {
+ .iov_base = &buf,
+ .iov_len = sizeof(buf),
+ };
+ struct inode *new;
+ int rc;
+
+ 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
