fs/smb/client: Implement new SMB3 POSIX type

Fixes special files against current Samba.

On the Samba server:

insgesamt 20
131958 brw-r--r--  1 root  root  0, 0 15. Nov 12:04 blockdev
131965 crw-r--r--  1 root  root  1, 1 15. Nov 12:04 chardev
131966 prw-r--r--  1 samba samba    0 15. Nov 12:05 fifo
131953 -rw-rwxrw-+ 2 samba samba    4 18. Nov 11:37 file
131953 -rw-rwxrw-+ 2 samba samba    4 18. Nov 11:37 hardlink
131957 lrwxrwxrwx  1 samba samba    4 15. Nov 12:03 symlink -> file
131954 -rwxrwxr-x+ 1 samba samba    0 18. Nov 15:28 symlinkoversmb

Before:

ls: cannot access '/mnt/smb3unix/posix/blockdev': No data available
ls: cannot access '/mnt/smb3unix/posix/chardev': No data available
ls: cannot access '/mnt/smb3unix/posix/symlinkoversmb': No data available
ls: cannot access '/mnt/smb3unix/posix/fifo': No data available
ls: cannot access '/mnt/smb3unix/posix/symlink': No data available
total 16
     ? -????????? ? ?    ?     ?            ? blockdev
     ? -????????? ? ?    ?     ?            ? chardev
     ? -????????? ? ?    ?     ?            ? fifo
131953 -rw-rwxrw- 2 root samba 4 Nov 18 11:37 file
131953 -rw-rwxrw- 2 root samba 4 Nov 18 11:37 hardlink
     ? -????????? ? ?    ?     ?            ? symlink
     ? -????????? ? ?    ?     ?            ? symlinkoversmb

After:

insgesamt 21
131958 brw-r--r-- 1 root root  0, 0 15. Nov 12:04 blockdev
131965 crw-r--r-- 1 root root  1, 1 15. Nov 12:04 chardev
131966 prw-r--r-- 1 root samba    0 15. Nov 12:05 fifo
131953 -rw-rwxrw- 2 root samba    4 18. Nov 11:37 file
131953 -rw-rwxrw- 2 root samba    4 18. Nov 11:37 hardlink
131957 lrwxrwxrwx 1 root samba    4 15. Nov 12:03 symlink -> file
131954 lrwxrwxr-x 1 root samba   23 18. Nov 15:28 symlinkoversmb -> mnt/smb3unix/posix/file

Cc: stable@vger.kernel.org
Acked-by: Paulo Alcantara (Red Hat) <pc@manguebit.com>
Signed-off-by: Ralph Boehme <slow@samba.org>
Signed-off-by: Steve French <stfrench@microsoft.com>

1 files changed, 52 insertions, 32 deletions

diff --git a/fs/smb/client/reparse.c b/fs/smb/client/reparse.c
index e81d2d78ddb7..50b1aba20008 100644
--- a/fs/smb/client/reparse.c
+++ b/fs/smb/client/reparse.c
@@ -803,44 +803,60 @@ out:
 	fattr->cf_dtype = S_DT(fattr->cf_mode);
 }
 
-bool cifs_reparse_point_to_fattr(struct cifs_sb_info *cifs_sb,
-				 struct cifs_fattr *fattr,
-				 struct cifs_open_info_data *data)
+static bool posix_reparse_to_fattr(struct cifs_sb_info *cifs_sb,
+				   struct cifs_fattr *fattr,
+				   struct cifs_open_info_data *data)
 {
 	struct reparse_posix_data *buf = data->reparse.posix;
-	u32 tag = data->reparse.tag;
 
-	if (tag == IO_REPARSE_TAG_NFS && buf) {
-		if (le16_to_cpu(buf->ReparseDataLength) < sizeof(buf->InodeType))
+
+	if (buf == NULL)
+		return true;
+
+	if (le16_to_cpu(buf->ReparseDataLength) < sizeof(buf->InodeType)) {
+		WARN_ON_ONCE(1);
+		return false;
+	}
+
+	switch (le64_to_cpu(buf->InodeType)) {
+	case NFS_SPECFILE_CHR:
+		if (le16_to_cpu(buf->ReparseDataLength) != sizeof(buf->InodeType) + 8) {
+			WARN_ON_ONCE(1);
 			return false;
-		switch (le64_to_cpu(buf->InodeType)) {
-		case NFS_SPECFILE_CHR:
-			if (le16_to_cpu(buf->ReparseDataLength) != sizeof(buf->InodeType) + 8)
-				return false;
-			fattr->cf_mode |= S_IFCHR;
-			fattr->cf_rdev = reparse_mkdev(buf->DataBuffer);
-			break;
-		case NFS_SPECFILE_BLK:
-			if (le16_to_cpu(buf->ReparseDataLength) != sizeof(buf->InodeType) + 8)
-				return false;
-			fattr->cf_mode |= S_IFBLK;
-			fattr->cf_rdev = reparse_mkdev(buf->DataBuffer);
-			break;
-		case NFS_SPECFILE_FIFO:
-			fattr->cf_mode |= S_IFIFO;
-			break;
-		case NFS_SPECFILE_SOCK:
-			fattr->cf_mode |= S_IFSOCK;
-			break;
-		case NFS_SPECFILE_LNK:
-			fattr->cf_mode |= S_IFLNK;
-			break;
-		default:
+		}
+		fattr->cf_mode |= S_IFCHR;
+		fattr->cf_rdev = reparse_mkdev(buf->DataBuffer);
+		break;
+	case NFS_SPECFILE_BLK:
+		if (le16_to_cpu(buf->ReparseDataLength) != sizeof(buf->InodeType) + 8) {
 			WARN_ON_ONCE(1);
 			return false;
 		}
-		goto out;
+		fattr->cf_mode |= S_IFBLK;
+		fattr->cf_rdev = reparse_mkdev(buf->DataBuffer);
+		break;
+	case NFS_SPECFILE_FIFO:
+		fattr->cf_mode |= S_IFIFO;
+		break;
+	case NFS_SPECFILE_SOCK:
+		fattr->cf_mode |= S_IFSOCK;
+		break;
+	case NFS_SPECFILE_LNK:
+		fattr->cf_mode |= S_IFLNK;
+		break;
+	default:
+		WARN_ON_ONCE(1);
+		return false;
 	}
+	return true;
+}
+
+bool cifs_reparse_point_to_fattr(struct cifs_sb_info *cifs_sb,
+				 struct cifs_fattr *fattr,
+				 struct cifs_open_info_data *data)
+{
+	u32 tag = data->reparse.tag;
+	bool ok;
 
 	switch (tag) {
 	case IO_REPARSE_TAG_INTERNAL:
@@ -860,15 +876,19 @@ bool cifs_reparse_point_to_fattr(struct cifs_sb_info *cifs_sb,
 	case IO_REPARSE_TAG_LX_BLK:
 		wsl_to_fattr(data, cifs_sb, tag, fattr);
 		break;
+	case IO_REPARSE_TAG_NFS:
+		ok = posix_reparse_to_fattr(cifs_sb, fattr, data);
+		if (!ok)
+			return false;
+		break;
 	case 0: /* SMB1 symlink */
 	case IO_REPARSE_TAG_SYMLINK:
-	case IO_REPARSE_TAG_NFS:
 		fattr->cf_mode |= S_IFLNK;
 		break;
 	default:
 		return false;
 	}
-out:
+
 	fattr->cf_dtype = S_DT(fattr->cf_mode);
 	return true;
 }