---

yaml
---
r: 83371
b: refs/heads/master
c: 19c561a
h: refs/heads/master
i:
  83369: 0e50695
  83367: 5d66adb
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 20292bc2c3feaee7f2e93911ffcb692732293894
+refs/heads/master: 19c561a60ffe52df88dd63de0bff480ca094efe4

trunk/fs/fat/file.c

@@ -155,6 +155,42 @@ static int fat_cont_expand(struct inode *inode, loff_t size)
 	return err;
 }
 
+static int check_mode(const struct msdos_sb_info *sbi, mode_t mode)
+{
+	mode_t req = mode & ~S_IFMT;
+
+	/*
+	 * Of the r and x bits, all (subject to umask) must be present. Of the
+	 * w bits, either all (subject to umask) or none must be present.
+	 */
+
+	if (S_ISREG(mode)) {
+		req &= ~sbi->options.fs_fmask;
+
+		if ((req & (S_IRUGO | S_IXUGO)) !=
+		    ((S_IRUGO | S_IXUGO) & ~sbi->options.fs_fmask))
+			return -EPERM;
+
+		if ((req & S_IWUGO) != 0 &&
+		    (req & S_IWUGO) != (S_IWUGO & ~sbi->options.fs_fmask))
+			return -EPERM;
+	} else if (S_ISDIR(mode)) {
+		req &= ~sbi->options.fs_dmask;
+
+		if ((req & (S_IRUGO | S_IXUGO)) !=
+		    ((S_IRUGO | S_IXUGO) & ~sbi->options.fs_dmask))
+			return -EPERM;
+
+		if ((req & S_IWUGO) != 0 &&
+		    (req & S_IWUGO) != (S_IWUGO & ~sbi->options.fs_dmask))
+			return -EPERM;
+	} else {
+		return -EPERM;
+	}
+
+	return 0;
+}
+
 int fat_notify_change(struct dentry *dentry, struct iattr *attr)
 {
 	struct msdos_sb_info *sbi = MSDOS_SB(dentry->d_sb);
@@ -186,16 +222,21 @@ int fat_notify_change(struct dentry *dentry, struct iattr *attr)
 	if (((attr->ia_valid & ATTR_UID) &&
 	     (attr->ia_uid != sbi->options.fs_uid)) ||
 	    ((attr->ia_valid & ATTR_GID) &&
-	     (attr->ia_gid != sbi->options.fs_gid)) ||
-	    ((attr->ia_valid & ATTR_MODE) &&
-	     (attr->ia_mode & ~MSDOS_VALID_MODE)))
+	     (attr->ia_gid != sbi->options.fs_gid)))
 		error = -EPERM;
 
 	if (error) {
 		if (sbi->options.quiet)
 			error = 0;
 		goto out;
 	}
+
+	if (attr->ia_valid & ATTR_MODE) {
+		error = check_mode(sbi, attr->ia_mode);
+		if (error != 0 && !sbi->options.quiet)
+			goto out;
+	}
+
 	error = inode_setattr(inode, attr);
 	if (error)
 		goto out;