1 files changed, 25 insertions, 12 deletions

diff --git a/fs/smb/client/reparse.c b/fs/smb/client/reparse.c
index d3abb99cc990..4d45c31336df 100644
--- a/fs/smb/client/reparse.c
+++ b/fs/smb/client/reparse.c
@@ -633,8 +633,6 @@ int parse_reparse_point(struct reparse_data_buffer *buf,
 			const char *full_path,
 			bool unicode, struct cifs_open_info_data *data)
 {
-	struct cifs_tcon *tcon = cifs_sb_master_tcon(cifs_sb);
-
 	data->reparse.buf = buf;
 
 	/* See MS-FSCC 2.1.2 */
@@ -651,13 +649,15 @@ int parse_reparse_point(struct reparse_data_buffer *buf,
 	case IO_REPARSE_TAG_LX_FIFO:
 	case IO_REPARSE_TAG_LX_CHR:
 	case IO_REPARSE_TAG_LX_BLK:
-		break;
+		if (le16_to_cpu(buf->ReparseDataLength) != 0) {
+			cifs_dbg(VFS, "srv returned malformed buffer for reparse point: 0x%08x\n",
+				 le32_to_cpu(buf->ReparseTag));
+			return -EIO;
+		}
+		return 0;
 	default:
-		cifs_tcon_dbg(VFS | ONCE, "unhandled reparse tag: 0x%08x\n",
-			      le32_to_cpu(buf->ReparseTag));
-		break;
+		return -EOPNOTSUPP;
 	}
-	return 0;
 }
 
 int smb2_parse_reparse_point(struct cifs_sb_info *cifs_sb,
@@ -674,11 +674,12 @@ int smb2_parse_reparse_point(struct cifs_sb_info *cifs_sb,
 	return parse_reparse_point(buf, plen, cifs_sb, full_path, true, data);
 }
 
-static void wsl_to_fattr(struct cifs_open_info_data *data,
+static bool wsl_to_fattr(struct cifs_open_info_data *data,
 			 struct cifs_sb_info *cifs_sb,
 			 u32 tag, struct cifs_fattr *fattr)
 {
 	struct smb2_file_full_ea_info *ea;
+	bool have_xattr_dev = false;
 	u32 next = 0;
 
 	switch (tag) {
@@ -721,13 +722,23 @@ static void wsl_to_fattr(struct cifs_open_info_data *data,
 			fattr->cf_uid = wsl_make_kuid(cifs_sb, v);
 		else if (!strncmp(name, SMB2_WSL_XATTR_GID, nlen))
 			fattr->cf_gid = wsl_make_kgid(cifs_sb, v);
-		else if (!strncmp(name, SMB2_WSL_XATTR_MODE, nlen))
+		else if (!strncmp(name, SMB2_WSL_XATTR_MODE, nlen)) {
+			/* File type in reparse point tag and in xattr mode must match. */
+			if (S_DT(fattr->cf_mode) != S_DT(le32_to_cpu(*(__le32 *)v)))
+				return false;
 			fattr->cf_mode = (umode_t)le32_to_cpu(*(__le32 *)v);
-		else if (!strncmp(name, SMB2_WSL_XATTR_DEV, nlen))
+		} else if (!strncmp(name, SMB2_WSL_XATTR_DEV, nlen)) {
 			fattr->cf_rdev = reparse_mkdev(v);
+			have_xattr_dev = true;
+		}
 	} while (next);
 out:
-	fattr->cf_dtype = S_DT(fattr->cf_mode);
+
+	/* Major and minor numbers for char and block devices are mandatory. */
+	if (!have_xattr_dev && (tag == IO_REPARSE_TAG_LX_CHR || tag == IO_REPARSE_TAG_LX_BLK))
+		return false;
+
+	return true;
 }
 
 static bool posix_reparse_to_fattr(struct cifs_sb_info *cifs_sb,
@@ -801,7 +812,9 @@ bool cifs_reparse_point_to_fattr(struct cifs_sb_info *cifs_sb,
 	case IO_REPARSE_TAG_AF_UNIX:
 	case IO_REPARSE_TAG_LX_CHR:
 	case IO_REPARSE_TAG_LX_BLK:
-		wsl_to_fattr(data, cifs_sb, tag, fattr);
+		ok = wsl_to_fattr(data, cifs_sb, tag, fattr);
+		if (!ok)
+			return false;
 		break;
 	case IO_REPARSE_TAG_NFS:
 		ok = posix_reparse_to_fattr(cifs_sb, fattr, data);