From: KP Singh <kpsingh@chromium.org>
To: linux-kernel@vger.kernel.org, bpf@vger.kernel.org,
linux-security-module@vger.kernel.org
Cc: "Alexei Starovoitov" <ast@kernel.org>,
"Daniel Borkmann" <daniel@iogearbox.net>,
"James Morris" <jmorris@namei.org>,
"Kees Cook" <keescook@chromium.org>,
"Thomas Garnier" <thgarnie@chromium.org>,
"Michael Halcrow" <mhalcrow@google.com>,
"Paul Turner" <pjt@google.com>,
"Brendan Gregg" <brendan.d.gregg@gmail.com>,
"Jann Horn" <jannh@google.com>,
"Matthew Garrett" <mjg59@google.com>,
"Christian Brauner" <christian@brauner.io>,
"Mickaël Salaün" <mic@digikod.net>,
"Florent Revest" <revest@chromium.org>,
"Martin KaFai Lau" <kafai@fb.com>,
"Song Liu" <songliubraving@fb.com>, "Yonghong Song" <yhs@fb.com>,
"Serge E. Hallyn" <serge@hallyn.com>,
"Mauro Carvalho Chehab" <mchehab+samsung@kernel.org>,
"David S. Miller" <davem@davemloft.net>,
"Greg Kroah-Hartman" <gregkh@linuxfoundation.org>,
"Nicolas Ferre" <nicolas.ferre@microchip.com>,
"Stanislav Fomichev" <sdf@google.com>,
"Quentin Monnet" <quentin.monnet@netronome.com>,
"Andrey Ignatov" <rdna@fb.com>, "Joe Stringer" <joe@wand.net.nz>
Subject: [RFC v1 08/14] krsi: Show attached program names in hook read handler.
Date: Tue, 10 Sep 2019 13:55:21 +0200 [thread overview]
Message-ID: <20190910115527.5235-9-kpsingh@chromium.org> (raw)
In-Reply-To: <20190910115527.5235-1-kpsingh@chromium.org>
From: KP Singh <kpsingh@google.com>
For inspectability the system administrator should be able to view the
list of active KRSI programs:
bash # cat /sys/kernel/security/krsi/process_execution
bpf_prog1
Signed-off-by: KP Singh <kpsingh@google.com>
---
security/krsi/krsi_fs.c | 76 ++++++++++++++++++++++++++++++++++++++++-
1 file changed, 75 insertions(+), 1 deletion(-)
diff --git a/security/krsi/krsi_fs.c b/security/krsi/krsi_fs.c
index 3ba18b52ce85..0ebf4fabe935 100644
--- a/security/krsi/krsi_fs.c
+++ b/security/krsi/krsi_fs.c
@@ -6,6 +6,7 @@
#include <linux/fs.h>
#include <linux/types.h>
#include <linux/filter.h>
+#include <linux/seq_file.h>
#include <linux/bpf.h>
#include <linux/security.h>
@@ -16,8 +17,81 @@ extern struct krsi_hook krsi_hooks_list[];
static struct dentry *krsi_dir;
+static void *seq_start(struct seq_file *m, loff_t *pos)
+ __acquires(rcu)
+{
+ struct krsi_hook *h;
+ struct dentry *dentry;
+ struct bpf_prog_array *progs;
+ struct bpf_prog_array_item *item;
+
+ /*
+ * rcu_read_lock() must be held before any return statement
+ * because the stop() will always be called and thus call
+ * rcu_read_unlock()
+ */
+ rcu_read_lock();
+
+ dentry = file_dentry(m->file);
+ h = dentry->d_fsdata;
+ if (WARN_ON(!h))
+ return ERR_PTR(-EFAULT);
+
+ progs = rcu_dereference(h->progs);
+ if ((*pos) >= bpf_prog_array_length(progs))
+ return NULL;
+
+ item = progs->items + *pos;
+ if (!item->prog)
+ return NULL;
+
+ return item;
+}
+
+static void *seq_next(struct seq_file *m, void *v, loff_t *pos)
+{
+ struct bpf_prog_array_item *item = v;
+
+ item++;
+ ++*pos;
+
+ if (!item->prog)
+ return NULL;
+
+ return item;
+}
+
+static void seq_stop(struct seq_file *m, void *v)
+ __releases(rcu)
+{
+ rcu_read_unlock();
+}
+
+static int show_prog(struct seq_file *m, void *v)
+{
+ struct bpf_prog_array_item *item = v;
+
+ seq_printf(m, "%s\n", item->prog->aux->name);
+ return 0;
+}
+
+static const struct seq_operations seq_ops = {
+ .show = show_prog,
+ .start = seq_start,
+ .next = seq_next,
+ .stop = seq_stop,
+};
+
+static int hook_open(struct inode *inode, struct file *file)
+{
+ return seq_open(file, &seq_ops);
+}
+
static const struct file_operations krsi_hook_ops = {
- .llseek = generic_file_llseek,
+ .open = hook_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = seq_release,
};
int krsi_fs_initialized;
--
2.20.1
next prev parent reply other threads:[~2019-09-10 11:57 UTC|newest]
Thread overview: 28+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-09-10 11:55 [RFC v1 00/14] Kernel Runtime Security Instrumentation KP Singh
2019-09-10 11:55 ` [RFC v1 01/14] krsi: Add a skeleton and config options for the KRSI LSM KP Singh
2019-09-10 11:55 ` [RFC v1 02/14] krsi: Introduce types for KRSI eBPF KP Singh
2019-09-10 11:55 ` [RFC v1 03/14] bpf: krsi: sync BPF UAPI header with tools KP Singh
2019-09-10 11:55 ` [RFC v1 04/14] krsi: Add support in libbpf for BPF_PROG_TYPE_KRSI KP Singh
2019-09-14 16:09 ` Yonghong Song
2019-09-10 11:55 ` [RFC v1 05/14] krsi: Initialize KRSI hooks and create files in securityfs KP Singh
2019-09-14 16:26 ` Yonghong Song
2019-09-10 11:55 ` [RFC v1 06/14] krsi: Implement eBPF operations, attachment and execution KP Singh
2019-09-14 16:56 ` Yonghong Song
2019-09-15 0:37 ` Yonghong Song
2019-09-10 11:55 ` [RFC v1 07/14] krsi: Check for premissions on eBPF attachment KP Singh
2019-09-10 11:55 ` KP Singh [this message]
2019-09-10 11:55 ` [RFC v1 09/14] krsi: Add a helper function for bpf_perf_event_output KP Singh
2019-09-14 18:23 ` Yonghong Song
2019-09-10 11:55 ` [RFC v1 10/14] krsi: Handle attachment of the same program KP Singh
2019-09-10 11:55 ` [RFC v1 11/14] krsi: Pin argument pages in bprm_check_security hook KP Singh
2019-09-10 11:55 ` [RFC v1 12/14] krsi: Add an eBPF helper function to get the value of an env variable KP Singh
2019-09-15 0:16 ` Yonghong Song
2019-09-16 13:00 ` KP Singh
2019-09-17 16:58 ` Yonghong Song
2019-09-17 19:36 ` KP Singh
2019-09-10 11:55 ` [RFC v1 13/14] krsi: Provide an example to read and log environment variables KP Singh
2019-09-15 0:24 ` Yonghong Song
2019-09-10 11:55 ` [RFC v1 14/14] krsi: Pin arg pages only when needed KP Singh
2019-09-15 0:33 ` Yonghong Song
2019-09-15 1:40 ` KP Singh
2019-09-15 19:45 ` Yonghong Song
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