audit: log module name on init_module

This adds a new auxiliary record MODULE_INIT to the SYSCALL event.

We get finit_module for free since it made most sense to hook this in to
load_module().

https://github.com/linux-audit/audit-kernel/issues/7
https://github.com/linux-audit/audit-kernel/wiki/RFE-Module-Load-Record-Format

Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
Acked-by: Jessica Yu <jeyu@redhat.com>
[PM: corrected links in the commit description]
Signed-off-by: Paul Moore <paul@paul-moore.com>

5 files changed, 34 insertions, 1 deletions

diff --git a/include/linux/audit.h b/include/linux/audit.h
index 2be99b276d29..aba3a2684300 100644
--- a/include/linux/audit.h
+++ b/include/linux/audit.h
@@ -360,6 +360,7 @@ extern int __audit_log_bprm_fcaps(struct linux_binprm *bprm,
                                   const struct cred *old);
 extern void __audit_log_capset(const struct cred *new, const struct cred *old);
 extern void __audit_mmap_fd(int fd, int flags);
+extern void __audit_log_kern_module(char *name);
 
 static inline void audit_ipc_obj(struct kern_ipc_perm *ipcp)
 {
@@ -450,6 +451,12 @@ static inline void audit_mmap_fd(int fd, int flags)
                 __audit_mmap_fd(fd, flags);
 }
 
+static inline void audit_log_kern_module(char *name)
+{
+        if (!audit_dummy_context())
+                __audit_log_kern_module(name);
+}
+
 extern int audit_n_rules;
 extern int audit_signals;
 #else /* CONFIG_AUDITSYSCALL */
@@ -561,6 +568,11 @@ static inline void audit_log_capset(const struct cred *new,
 { }
 static inline void audit_mmap_fd(int fd, int flags)
 { }
+
+static inline void audit_log_kern_module(char *name)
+{
+}
+
 static inline void audit_ptrace(struct task_struct *t)
 { }
 #define audit_n_rules 0
diff --git a/include/uapi/linux/audit.h b/include/uapi/linux/audit.h
index 3f24110ae63c..3c02bb2ff779 100644
--- a/include/uapi/linux/audit.h
+++ b/include/uapi/linux/audit.h
@@ -111,6 +111,7 @@
 #define AUDIT_PROCTITLE         1327    /* Proctitle emit event */
 #define AUDIT_FEATURE_CHANGE    1328    /* audit log listing feature changes */
 #define AUDIT_REPLACE           1329    /* Replace auditd if this packet unanswerd */
+#define AUDIT_KERN_MODULE       1330    /* Kernel Module events */
 
 #define AUDIT_AVC               1400    /* SE Linux avc denial or grant */
 #define AUDIT_SELINUX_ERR       1401    /* Internal SE Linux Errors */
diff --git a/kernel/audit.h b/kernel/audit.h
index 431444c3708b..144b7ebd2deb 100644
--- a/kernel/audit.h
+++ b/kernel/audit.h
@@ -199,6 +199,9 @@ struct audit_context {
                 struct {
                         int                     argc;
                 } execve;
+                struct {
+                        char                    *name;
+                } module;
         };
         int fds[2];
         struct audit_proctitle proctitle;
diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index bb5f504592c6..bde3aac4deed 100644
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -1268,6 +1268,11 @@ static void show_special(struct audit_context *context, int *call_panic)
         case AUDIT_EXECVE: {
                 audit_log_execve_info(context, &ab);
                 break; }
+        case AUDIT_KERN_MODULE:
+                audit_log_format(ab, "name=");
+                audit_log_untrustedstring(ab, context->module.name);
+                kfree(context->module.name);
+                break;
         }
         audit_log_end(ab);
 }
@@ -2368,6 +2373,15 @@ void __audit_mmap_fd(int fd, int flags)
         context->type = AUDIT_MMAP;
 }
 
+void __audit_log_kern_module(char *name)
+{
+        struct audit_context *context = current->audit_context;
+
+        context->module.name = kmalloc(strlen(name) + 1, GFP_KERNEL);
+        strcpy(context->module.name, name);
+        context->type = AUDIT_KERN_MODULE;
+}
+
 static void audit_log_task(struct audit_buffer *ab)
 {
         kuid_t auid, uid;
diff --git a/kernel/module.c b/kernel/module.c
index 529efae9f481..5432dbedf8cf 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -61,6 +61,7 @@
 #include <linux/pfn.h>
 #include <linux/bsearch.h>
 #include <linux/dynamic_debug.h>
+#include <linux/audit.h>
 #include <uapi/linux/module.h>
 #include "module-internal.h"
 
@@ -3593,6 +3594,8 @@ static int load_module(struct load_info *info, const char __user *uargs,
                 goto free_copy;
         }
 
+        audit_log_kern_module(mod->name);
+
         /* Reserve our place in the list. */
         err = add_unformed_module(mod);
         if (err)
@@ -3681,7 +3684,7 @@ static int load_module(struct load_info *info, const char __user *uargs,
                        mod->name, after_dashes);
         }
 
-        /* Link in to syfs. */
+        /* Link in to sysfs. */
         err = mod_sysfs_setup(mod, info, mod->kp, mod->num_kp);
         if (err < 0)
                 goto coming_cleanup;