diff options
author | Eric Paris <eparis@redhat.com> | 2007-06-28 15:55:21 -0400 |
---|---|---|
committer | James Morris <jmorris@namei.org> | 2007-07-11 22:52:29 -0400 |
commit | ed0321895182ffb6ecf210e066d87911b270d587 (patch) | |
tree | 832bb54666f73b06e55322df40f915c5e9ef64d7 /security/selinux/include | |
parent | 13bddc2e9d591e31bf20020dc19ea6ca85de420e (diff) | |
download | op-kernel-dev-ed0321895182ffb6ecf210e066d87911b270d587.zip op-kernel-dev-ed0321895182ffb6ecf210e066d87911b270d587.tar.gz |
security: Protection for exploiting null dereference using mmap
Add a new security check on mmap operations to see if the user is attempting
to mmap to low area of the address space. The amount of space protected is
indicated by the new proc tunable /proc/sys/vm/mmap_min_addr and defaults to
0, preserving existing behavior.
This patch uses a new SELinux security class "memprotect." Policy already
contains a number of allow rules like a_t self:process * (unconfined_t being
one of them) which mean that putting this check in the process class (its
best current fit) would make it useless as all user processes, which we also
want to protect against, would be allowed. By taking the memprotect name of
the new class it will also make it possible for us to move some of the other
memory protect permissions out of 'process' and into the new class next time
we bump the policy version number (which I also think is a good future idea)
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Acked-by: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
Diffstat (limited to 'security/selinux/include')
-rw-r--r-- | security/selinux/include/av_perm_to_string.h | 1 | ||||
-rw-r--r-- | security/selinux/include/av_permissions.h | 1 | ||||
-rw-r--r-- | security/selinux/include/class_to_string.h | 1 | ||||
-rw-r--r-- | security/selinux/include/flask.h | 1 |
4 files changed, 4 insertions, 0 deletions
diff --git a/security/selinux/include/av_perm_to_string.h b/security/selinux/include/av_perm_to_string.h index b83e740..049bf69 100644 --- a/security/selinux/include/av_perm_to_string.h +++ b/security/selinux/include/av_perm_to_string.h @@ -158,3 +158,4 @@ S_(SECCLASS_KEY, KEY__CREATE, "create") S_(SECCLASS_DCCP_SOCKET, DCCP_SOCKET__NODE_BIND, "node_bind") S_(SECCLASS_DCCP_SOCKET, DCCP_SOCKET__NAME_CONNECT, "name_connect") + S_(SECCLASS_MEMPROTECT, MEMPROTECT__MMAP_ZERO, "mmap_zero") diff --git a/security/selinux/include/av_permissions.h b/security/selinux/include/av_permissions.h index 5fee173..eda89a2 100644 --- a/security/selinux/include/av_permissions.h +++ b/security/selinux/include/av_permissions.h @@ -823,3 +823,4 @@ #define DCCP_SOCKET__NAME_BIND 0x00200000UL #define DCCP_SOCKET__NODE_BIND 0x00400000UL #define DCCP_SOCKET__NAME_CONNECT 0x00800000UL +#define MEMPROTECT__MMAP_ZERO 0x00000001UL diff --git a/security/selinux/include/class_to_string.h b/security/selinux/include/class_to_string.h index 3787990..e77de0e 100644 --- a/security/selinux/include/class_to_string.h +++ b/security/selinux/include/class_to_string.h @@ -63,3 +63,4 @@ S_("key") S_(NULL) S_("dccp_socket") + S_("memprotect") diff --git a/security/selinux/include/flask.h b/security/selinux/include/flask.h index 35f309f..a9c2b20 100644 --- a/security/selinux/include/flask.h +++ b/security/selinux/include/flask.h @@ -49,6 +49,7 @@ #define SECCLASS_PACKET 57 #define SECCLASS_KEY 58 #define SECCLASS_DCCP_SOCKET 60 +#define SECCLASS_MEMPROTECT 61 /* * Security identifier indices for initial entities |