security: report the module name to security_module_request

For SELinux to do better filtering in userspace we send the name of the
module along with the AVC denial when a program is denied module_request.

Example output:

type=SYSCALL msg=audit(11/03/2009 10:59:43.510:9) : arch=x86_64 syscall=write success=yes exit=2 a0=3 a1=7fc28c0d56c0 a2=2 a3=7fffca0d7440 items=0 ppid=1727 pid=1729 auid=unset uid=root gid=root euid=root suid=root fsuid=root egid=root sgid=root fsgid=root tty=(none) ses=unset comm=rpc.nfsd exe=/usr/sbin/rpc.nfsd subj=system_u:system_r:nfsd_t:s0 key=(null)
type=AVC msg=audit(11/03/2009 10:59:43.510:9) : avc:  denied  { module_request } for  pid=1729 comm=rpc.nfsd kmod="net-pf-10" scontext=system_u:system_r:nfsd_t:s0 tcontext=system_u:system_r:kernel_t:s0 tclass=system

Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>

2 files changed, 14 insertions, 11 deletions

diff --git a/include/linux/lsm_audit.h b/include/linux/lsm_audit.h
index 190c3785487..f78f83d7663 100644
--- a/include/linux/lsm_audit.h
+++ b/include/linux/lsm_audit.h
@@ -26,14 +26,15 @@
 
 /* Auxiliary data to use in generating the audit record. */
 struct common_audit_data {
-	char    type;
-#define LSM_AUDIT_DATA_FS      1
-#define LSM_AUDIT_DATA_NET     2
-#define LSM_AUDIT_DATA_CAP     3
-#define LSM_AUDIT_DATA_IPC     4
-#define LSM_AUDIT_DATA_TASK    5
-#define LSM_AUDIT_DATA_KEY     6
-#define LSM_AUDIT_NO_AUDIT     7
+	char type;
+#define LSM_AUDIT_DATA_FS	1
+#define LSM_AUDIT_DATA_NET	2
+#define LSM_AUDIT_DATA_CAP	3
+#define LSM_AUDIT_DATA_IPC	4
+#define LSM_AUDIT_DATA_TASK	5
+#define LSM_AUDIT_DATA_KEY	6
+#define LSM_AUDIT_NO_AUDIT	7
+#define LSM_AUDIT_DATA_KMOD	8
 	struct task_struct *tsk;
 	union 	{
 		struct {
@@ -66,6 +67,7 @@ struct common_audit_data {
 			char *key_desc;
 		} key_struct;
 #endif
+		char *kmod_name;
 	} u;
 	/* this union contains LSM specific data */
 	union {
diff --git a/include/linux/security.h b/include/linux/security.h
index ed0faea60b8..466cbadbd1e 100644
--- a/include/linux/security.h
+++ b/include/linux/security.h
@@ -706,6 +706,7 @@ static inline void security_free_mnt_opts(struct security_mnt_opts *opts)
  * @kernel_module_request:
  *	Ability to trigger the kernel to automatically upcall to userspace for
  *	userspace to load a kernel module with the given name.
+ *	@kmod_name name of the module requested by the kernel
  *	Return 0 if successful.
  * @task_setuid:
  *	Check permission before setting one or more of the user identity
@@ -1577,7 +1578,7 @@ struct security_operations {
 	void (*cred_transfer)(struct cred *new, const struct cred *old);
 	int (*kernel_act_as)(struct cred *new, u32 secid);
 	int (*kernel_create_files_as)(struct cred *new, struct inode *inode);
-	int (*kernel_module_request)(void);
+	int (*kernel_module_request)(char *kmod_name);
 	int (*task_setuid) (uid_t id0, uid_t id1, uid_t id2, int flags);
 	int (*task_fix_setuid) (struct cred *new, const struct cred *old,
 				int flags);
@@ -1842,7 +1843,7 @@ void security_commit_creds(struct cred *new, const struct cred *old);
 void security_transfer_creds(struct cred *new, const struct cred *old);
 int security_kernel_act_as(struct cred *new, u32 secid);
 int security_kernel_create_files_as(struct cred *new, struct inode *inode);
-int security_kernel_module_request(void);
+int security_kernel_module_request(char *kmod_name);
 int security_task_setuid(uid_t id0, uid_t id1, uid_t id2, int flags);
 int security_task_fix_setuid(struct cred *new, const struct cred *old,
 			     int flags);
@@ -2407,7 +2408,7 @@ static inline int security_kernel_create_files_as(struct cred *cred,
 	return 0;
 }
 
-static inline int security_kernel_module_request(void)
+static inline int security_kernel_module_request(char *kmod_name)
 {
 	return 0;
 }