From: "Christian Göttsche" <cgzones@googlemail.com>
To: linux-security-module@vger.kernel.org
Cc: Alexander Viro <viro@zeniv.linux.org.uk>,
Christian Brauner <brauner@kernel.org>, Jan Kara <jack@suse.cz>,
Eric Biederman <ebiederm@xmission.com>,
Kees Cook <keescook@chromium.org>,
Paul Moore <paul@paul-moore.com>,
James Morris <jmorris@namei.org>,
"Serge E. Hallyn" <serge@hallyn.com>,
Stephen Smalley <stephen.smalley.work@gmail.com>,
Ondrej Mosnacek <omosnace@redhat.com>,
Khadija Kamran <kamrankhadijadj@gmail.com>,
Andrii Nakryiko <andrii@kernel.org>,
Casey Schaufler <casey@schaufler-ca.com>,
Alexei Starovoitov <ast@kernel.org>,
Roberto Sassu <roberto.sassu@huawei.com>,
Guillaume Nault <gnault@redhat.com>,
John Johansen <john.johansen@canonical.com>,
Alfred Piccioni <alpic@google.com>,
linux-fsdevel@vger.kernel.org, linux-mm@kvack.org,
linux-kernel@vger.kernel.org, selinux@vger.kernel.org
Subject: [RFC PATCH 2/2] selinux: wire up new execstack LSM hook
Date: Fri, 15 Mar 2024 19:08:47 +0100 [thread overview]
Message-ID: <20240315181032.645161-1-cgzones@googlemail.com> (raw)
Perform a process { execstack } check unless virtual memory is marked
executable by default.
Signed-off-by: Christian Göttsche <cgzones@googlemail.com>
---
security/selinux/hooks.c | 17 +++++++++++++++--
1 file changed, 15 insertions(+), 2 deletions(-)
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index a0fde0641f77..daf901916836 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -113,6 +113,8 @@ struct selinux_state selinux_state;
/* SECMARK reference count */
static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
+static int default_noexec __ro_after_init;
+
#ifdef CONFIG_SECURITY_SELINUX_DEVELOP
static int selinux_enforcing_boot __initdata;
@@ -2221,6 +2223,18 @@ static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
return cap_sys_admin;
}
+static int selinux_vm_execstack(void)
+{
+ u32 sid;
+
+ if (!default_noexec)
+ return 0;
+
+ sid = current_sid();
+ return avc_has_perm(sid, sid, SECCLASS_PROCESS,
+ PROCESS__EXECSTACK, NULL);
+}
+
/* binprm security operations */
static u32 ptrace_parent_sid(void)
@@ -3767,8 +3781,6 @@ static int selinux_file_ioctl_compat(struct file *file, unsigned int cmd,
return selinux_file_ioctl(file, cmd, arg);
}
-static int default_noexec __ro_after_init;
-
static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
{
const struct cred *cred = current_cred();
@@ -7120,6 +7132,7 @@ static struct security_hook_list selinux_hooks[] __ro_after_init = {
LSM_HOOK_INIT(quota_on, selinux_quota_on),
LSM_HOOK_INIT(syslog, selinux_syslog),
LSM_HOOK_INIT(vm_enough_memory, selinux_vm_enough_memory),
+ LSM_HOOK_INIT(vm_execstack, selinux_vm_execstack),
LSM_HOOK_INIT(netlink_send, selinux_netlink_send),
--
2.43.0
next reply other threads:[~2024-03-15 18:10 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-03-15 18:08 Christian Göttsche [this message]
2024-03-15 18:08 ` [RFC PATCH 1/2] lsm: introduce new hook security_vm_execstack Christian Göttsche
2024-03-15 18:22 ` Casey Schaufler
2024-03-15 18:30 ` Christian Göttsche
2024-03-15 18:41 ` Casey Schaufler
2024-03-15 20:22 ` Paul Moore
2024-03-16 3:24 ` Kees Cook
2024-03-19 23:10 ` Paul Moore
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