Merge branch 'cm-14.1' of https://github.com/LineageOS/android_kernel_oneplus_msm8974 into n7.1HEADn7.1

1 files changed, 29 insertions, 0 deletions

diff --git a/fs/posix_acl.c b/fs/posix_acl.c
index 64496020bf1..9607a1df282 100644
--- a/fs/posix_acl.c
+++ b/fs/posix_acl.c
@@ -341,6 +341,35 @@ static int posix_acl_create_masq(struct posix_acl *acl, umode_t *mode_p)
         return not_equiv;
 }
 
+/**
+ * posix_acl_update_mode  -  update mode in set_acl
+ *
+ * Update the file mode when setting an ACL: compute the new file permission
+ * bits based on the ACL.  In addition, if the ACL is equivalent to the new
+ * file mode, set *acl to NULL to indicate that no ACL should be set.
+ *
+ * As with chmod, clear the setgit bit if the caller is not in the owning group
+ * or capable of CAP_FSETID (see inode_change_ok).
+ *
+ * Called from set_acl inode operations.
+ */
+int posix_acl_update_mode(struct inode *inode, umode_t *mode_p,
+			  struct posix_acl **acl)
+{
+	umode_t mode = inode->i_mode;
+	int error;
+
+	error = posix_acl_update_mode(inode, &inode->i_mode, acl);
+	if (error)
+		return error;
+	if (!in_group_p(inode->i_gid) &&
+	    !capable(CAP_FSETID))
+		mode &= ~S_ISGID;
+	*mode_p = mode;
+	return 0;
+}
+EXPORT_SYMBOL(posix_acl_update_mode);
+
 /*
  * Modify the ACL for the chmod syscall.
  */