From 8a56038c2aef97a9d4b9dd608b912b9d9a4a2d68 Mon Sep 17 00:00:00 2001
From: Kees Cook <keescook@chromium.org>
Date: Wed, 20 Apr 2016 15:46:26 -0700
Subject: [PATCH] Yama: consolidate error reporting
Use a common error reporting function for Yama violation reports, and give
more detail into the process command lines.
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: James Morris <james.l.morris@oracle.com>
---
security/yama/yama_lsm.c | 31 +++++++++++++++++++++----------
1 file changed, 21 insertions(+), 10 deletions(-)
diff --git a/security/yama/yama_lsm.c b/security/yama/yama_lsm.c
index cb6ed10816d49..c19f6e5df9a38 100644
--- a/security/yama/yama_lsm.c
+++ b/security/yama/yama_lsm.c
@@ -18,6 +18,7 @@
#include <linux/prctl.h>
#include <linux/ratelimit.h>
#include <linux/workqueue.h>
+#include <linux/string_helpers.h>
#define YAMA_SCOPE_DISABLED 0
#define YAMA_SCOPE_RELATIONAL 1
@@ -41,6 +42,22 @@ static DEFINE_SPINLOCK(ptracer_relations_lock);
static void yama_relation_cleanup(struct work_struct *work);
static DECLARE_WORK(yama_relation_work, yama_relation_cleanup);
+static void report_access(const char *access, struct task_struct *target,
+ struct task_struct *agent)
+{
+ char *target_cmd, *agent_cmd;
+
+ target_cmd = kstrdup_quotable_cmdline(target, GFP_KERNEL);
+ agent_cmd = kstrdup_quotable_cmdline(agent, GFP_KERNEL);
+
+ pr_notice_ratelimited(
+ "ptrace %s of \"%s\"[%d] was attempted by \"%s\"[%d]\n",
+ access, target_cmd, target->pid, agent_cmd, agent->pid);
+
+ kfree(agent_cmd);
+ kfree(target_cmd);
+}
+
/**
* yama_relation_cleanup - remove invalid entries from the relation list
*
@@ -307,11 +324,8 @@ static int yama_ptrace_access_check(struct task_struct *child,
}
}
- if (rc && (mode & PTRACE_MODE_NOAUDIT) == 0) {
- printk_ratelimited(KERN_NOTICE
- "ptrace of pid %d was attempted by: %s (pid %d)\n",
- child->pid, current->comm, current->pid);
- }
+ if (rc && (mode & PTRACE_MODE_NOAUDIT) == 0)
+ report_access("attach", child, current);
return rc;
}
@@ -337,11 +351,8 @@ int yama_ptrace_traceme(struct task_struct *parent)
break;
}
- if (rc) {
- printk_ratelimited(KERN_NOTICE
- "ptraceme of pid %d was attempted by: %s (pid %d)\n",
- current->pid, parent->comm, parent->pid);
- }
+ if (rc)
+ report_access("traceme", current, parent);
return rc;
}