From: David Howells <dhowells@redhat.com>
Date: Wed, 8 Nov 2017 15:11:37 +0000 (+0000)
Subject: Lock down /proc/kcore
X-Git-Tag: archive/raspbian/4.15.11-1+rpi1^2~23
X-Git-Url: https://dgit.raspbian.org/?a=commitdiff_plain;h=2ae1de956ead5ff52415707041c39b3cf0875675;p=linux.git

Lock down /proc/kcore

Disallow access to /proc/kcore when the kernel is locked down to prevent
access to cryptographic data.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: James Morris <james.l.morris@oracle.com>

Gbp-Pq: Topic features/all/lockdown
Gbp-Pq: Name 0025-Lock-down-proc-kcore.patch
---

diff --git a/fs/proc/kcore.c b/fs/proc/kcore.c
index e8a93bc8285..e463ef48966 100644
--- a/fs/proc/kcore.c
+++ b/fs/proc/kcore.c
@@ -542,6 +542,8 @@ read_kcore(struct file *file, char __user *buffer, size_t buflen, loff_t *fpos)
 
 static int open_kcore(struct inode *inode, struct file *filp)
 {
+	if (kernel_is_locked_down("/proc/kcore"))
+		return -EPERM;
 	if (!capable(CAP_SYS_RAWIO))
 		return -EPERM;