From: Paul Moore <paul@paul-moore.com>
Date: Thu, 9 Jun 2016 14:40:37 +0000 (-0400)
Subject: selinux: import NetLabel category bitmaps correctly
X-Git-Tag: v4.13~2590^2~35^2~21
X-Git-Url: https://git.proxmox.com/?a=commitdiff_plain;h=8bebe88c0995f331b0614f413285ce2b1d6fe09c;p=mirror_ubuntu-bionic-kernel.git

selinux: import NetLabel category bitmaps correctly

The existing ebitmap_netlbl_import() code didn't correctly handle the
case where the ebitmap_node was not aligned/sized to a power of two,
this patch fixes this (on x86_64 ebitmap_node contains six bitmaps
making a range of 0..383).

Signed-off-by: Paul Moore <paul@paul-moore.com>
---

diff --git a/security/selinux/ss/ebitmap.c b/security/selinux/ss/ebitmap.c
index 57644b1dc42e..894b6cdc11c5 100644
--- a/security/selinux/ss/ebitmap.c
+++ b/security/selinux/ss/ebitmap.c
@@ -165,7 +165,7 @@ int ebitmap_netlbl_import(struct ebitmap *ebmap,
 			e_iter = kzalloc(sizeof(*e_iter), GFP_ATOMIC);
 			if (e_iter == NULL)
 				goto netlbl_import_failure;
-			e_iter->startbit = offset & ~(EBITMAP_SIZE - 1);
+			e_iter->startbit = offset - (offset % EBITMAP_SIZE);
 			if (e_prev == NULL)
 				ebmap->node = e_iter;
 			else