[PATCH] Rework of IPC auditing
1) The audit_ipc_perms() function has been split into two different
functions:
- audit_ipc_obj()
- audit_ipc_set_perm()
There's a key shift here... The audit_ipc_obj() collects the uid, gid,
mode, and SElinux context label of the current ipc object. This
audit_ipc_obj() hook is now found in several places. Most notably, it
is hooked in ipcperms(), which is called in various places around the
ipc code permforming a MAC check. Additionally there are several places
where *checkid() is used to validate that an operation is being
performed on a valid object while not necessarily having a nearby
ipcperms() call. In these locations, audit_ipc_obj() is called to
ensure that the information is captured by the audit system.
The audit_set_new_perm() function is called any time the permissions on
the ipc object changes. In this case, the NEW permissions are recorded
(and note that an audit_ipc_obj() call exists just a few lines before
each instance).
2) Support for an AUDIT_IPC_SET_PERM audit message type. This allows
for separate auxiliary audit records for normal operations on an IPC
object and permissions changes. Note that the same struct
audit_aux_data_ipcctl is used and populated, however there are separate
audit_log_format statements based on the type of the message. Finally,
the AUDIT_IPC block of code in audit_free_aux() was extended to handle
aux messages of this new type. No more mem leaks I hope ;-)
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/ipc/shm.c b/ipc/shm.c
index 1c2faf6..8098968 100644
--- a/ipc/shm.c
+++ b/ipc/shm.c
@@ -13,6 +13,8 @@
* Shared /dev/zero support, Kanoj Sarcar <kanoj@sgi.com>
* Move the mm functionality over to mm/shmem.c, Christoph Rohland <cr@sap.com>
*
+ * support for audit of ipc object properties and permission changes
+ * Dustin Kirkland <dustin.kirkland@us.ibm.com>
*/
#include <linux/config.h>
@@ -542,6 +544,10 @@
if(err)
goto out_unlock;
+ err = audit_ipc_obj(&(shp->shm_perm));
+ if (err)
+ goto out_unlock;
+
if (!capable(CAP_IPC_LOCK)) {
err = -EPERM;
if (current->euid != shp->shm_perm.uid &&
@@ -594,6 +600,10 @@
if(err)
goto out_unlock_up;
+ err = audit_ipc_obj(&(shp->shm_perm));
+ if (err)
+ goto out_unlock_up;
+
if (current->euid != shp->shm_perm.uid &&
current->euid != shp->shm_perm.cuid &&
!capable(CAP_SYS_ADMIN)) {
@@ -627,12 +637,15 @@
err=-EINVAL;
if(shp==NULL)
goto out_up;
- if ((err = audit_ipc_perms(0, setbuf.uid, setbuf.gid,
- setbuf.mode, &(shp->shm_perm))))
- goto out_unlock_up;
err = shm_checkid(shp,shmid);
if(err)
goto out_unlock_up;
+ err = audit_ipc_obj(&(shp->shm_perm));
+ if (err)
+ goto out_unlock_up;
+ err = audit_ipc_set_perm(0, setbuf.uid, setbuf.gid, setbuf.mode, &(shp->shm_perm));
+ if (err)
+ goto out_unlock_up;
err=-EPERM;
if (current->euid != shp->shm_perm.uid &&
current->euid != shp->shm_perm.cuid &&
