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 if -o nonativesocket was not
specified.
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/cifsfs.c | 2 ++
fs/smb/client/connect.c | 2 ++
fs/smb/client/fs_context.c | 5 +++++
fs/smb/client/fs_context.h | 2 ++
fs/smb/client/reparse.c | 32 ++++++++++++++++++++++++++++++++
5 files changed, 43 insertions(+)
diff --git a/fs/smb/client/cifsfs.c b/fs/smb/client/cifsfs.c
index 39ec67d9808e..eb279d5c6bd3 100644
--- a/fs/smb/client/cifsfs.c
+++ b/fs/smb/client/cifsfs.c
@@ -689,6 +689,8 @@ cifs_show_options(struct seq_file *s, struct dentry *root)
cifs_sb->ctx->backupgid));
seq_show_option(s, "reparse",
cifs_reparse_type_str(cifs_sb->ctx->reparse_type));
+ if (cifs_sb->ctx->nonativesocket)
+ seq_puts(s, ",nonativesocket");
seq_show_option(s, "symlink",
cifs_symlink_type_str(get_cifs_symlink_type(cifs_sb)));
diff --git a/fs/smb/client/connect.c b/fs/smb/client/connect.c
index bc5b5100ac09..3db39f2ef5a8 100644
--- a/fs/smb/client/connect.c
+++ b/fs/smb/client/connect.c
@@ -2831,6 +2831,8 @@ compare_mount_options(struct super_block *sb, struct cifs_mnt_data *mnt_data)
return 0;
if (old->ctx->reparse_type != new->ctx->reparse_type)
return 0;
+ if (old->ctx->nonativesocket != new->ctx->nonativesocket)
+ return 0;
if (old->ctx->symlink_type != new->ctx->symlink_type)
return 0;
diff --git a/fs/smb/client/fs_context.c b/fs/smb/client/fs_context.c
index d68db6ac5f73..7f21630885cb 100644
--- a/fs/smb/client/fs_context.c
+++ b/fs/smb/client/fs_context.c
@@ -178,6 +178,7 @@ const struct fs_parameter_spec smb3_fs_parameters[] = {
fsparam_string("sec", Opt_sec),
fsparam_string("cache", Opt_cache),
fsparam_string("reparse", Opt_reparse),
+ fsparam_string("nativesocket", Opt_nativesocket),
fsparam_string("symlink", Opt_symlink),
fsparam_string("symlinkroot", Opt_symlinkroot),
@@ -1674,6 +1675,9 @@ static int smb3_fs_context_parse_param(struct fs_context *fc,
if (parse_reparse_flavor(fc, param->string, ctx))
goto cifs_parse_mount_err;
break;
+ case Opt_nativesocket:
+ ctx->nonativesocket = result.negated;
+ break;
case Opt_symlink:
if (parse_symlink_flavor(fc, param->string, ctx))
goto cifs_parse_mount_err;
@@ -1803,6 +1807,7 @@ int smb3_init_fs_context(struct fs_context *fc)
ctx->retrans = 1;
ctx->reparse_type = CIFS_REPARSE_TYPE_DEFAULT;
ctx->symlink_type = CIFS_SYMLINK_TYPE_DEFAULT;
+ ctx->nonativesocket = 0;
/*
* short int override_uid = -1;
diff --git a/fs/smb/client/fs_context.h b/fs/smb/client/fs_context.h
index 5f306f581fd1..18d39d457145 100644
--- a/fs/smb/client/fs_context.h
+++ b/fs/smb/client/fs_context.h
@@ -170,6 +170,7 @@ enum cifs_param {
Opt_sec,
Opt_cache,
Opt_reparse,
+ Opt_nativesocket,
Opt_symlink,
Opt_symlinkroot,
@@ -300,6 +301,7 @@ struct smb3_fs_context {
bool dfs_automount:1; /* set for dfs automount only */
enum cifs_reparse_type reparse_type;
enum cifs_symlink_type symlink_type;
+ bool nonativesocket:1;
bool dfs_conn:1; /* set for dfs mounts */
char *symlinkroot; /* top level directory for native SMB symlinks in absolute format */
};
diff --git a/fs/smb/client/reparse.c b/fs/smb/client/reparse.c
index d950c60323e8..57320a4c4d79 100644
--- a/fs/smb/client/reparse.c
+++ b/fs/smb/client/reparse.c
@@ -375,6 +375,35 @@ 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 = cpu_to_le16(0),
+ };
+ struct kvec iov = {
+ .iov_base = &buf,
+ .iov_len = sizeof(buf),
+ };
+ struct inode *new;
+ 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)
@@ -598,6 +627,9 @@ 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->nonativesocket && ctx->reparse_type != CIFS_REPARSE_TYPE_NONE)
+ return create_native_socket(xid, inode, dentry, tcon, full_path);
+
switch (ctx->reparse_type) {
case CIFS_REPARSE_TYPE_NFS:
return mknod_nfs(xid, inode, dentry, tcon, full_path, mode, dev, NULL);
--
2.20.1
