Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6: (43 commits)
  TOMOYO: Fix wrong domainname validation.
  SELINUX: add /sys/fs/selinux mount point to put selinuxfs
  CRED: Fix load_flat_shared_library() to initialise bprm correctly
  SELinux: introduce path_has_perm
  flex_array: allow 0 length elements
  flex_arrays: allow zero length flex arrays
  flex_array: flex_array_prealloc takes a number of elements, not an end
  SELinux: pass last path component in may_create
  SELinux: put name based create rules in a hashtable
  SELinux: generic hashtab entry counter
  SELinux: calculate and print hashtab stats with a generic function
  SELinux: skip filename trans rules if ttype does not match parent dir
  SELinux: rename filename_compute_type argument to *type instead of *con
  SELinux: fix comment to state filename_compute_type takes an objname not a qstr
  SMACK: smack_file_lock can use the struct path
  LSM: separate LSM_AUDIT_DATA_DENTRY from LSM_AUDIT_DATA_PATH
  LSM: split LSM_AUDIT_DATA_FS into _PATH and _INODE
  SELINUX: Make selinux cache VFS RCU walks safe
  SECURITY: Move exec_permission RCU checks into security modules
  SELinux: security_read_policy should take a size_t not ssize_t
  ...

kernel/capability.c

@@ -22,12 +22,8 @@
  */
 
 const kernel_cap_t __cap_empty_set = CAP_EMPTY_SET;
-const kernel_cap_t __cap_full_set = CAP_FULL_SET;
-const kernel_cap_t __cap_init_eff_set = CAP_INIT_EFF_SET;
 
 EXPORT_SYMBOL(__cap_empty_set);
-EXPORT_SYMBOL(__cap_full_set);
-EXPORT_SYMBOL(__cap_init_eff_set);
 
 int file_caps_enabled = 1;
 

kernel/cred.c

@@ -49,10 +49,10 @@ struct cred init_cred = {
 	.magic			= CRED_MAGIC,
 #endif
 	.securebits		= SECUREBITS_DEFAULT,
-	.cap_inheritable	= CAP_INIT_INH_SET,
+	.cap_inheritable	= CAP_EMPTY_SET,
 	.cap_permitted		= CAP_FULL_SET,
-	.cap_effective		= CAP_INIT_EFF_SET,
-	.cap_bset		= CAP_INIT_BSET,
+	.cap_effective		= CAP_FULL_SET,
+	.cap_bset		= CAP_FULL_SET,
 	.user			= INIT_USER,
 	.user_ns		= &init_user_ns,
 	.group_info		= &init_groups,

kernel/kmod.c

@@ -25,6 +25,7 @@
 #include <linux/kmod.h>
 #include <linux/slab.h>
 #include <linux/completion.h>
+#include <linux/cred.h>
 #include <linux/file.h>
 #include <linux/fdtable.h>
 #include <linux/workqueue.h>
@@ -43,6 +44,13 @@ extern int max_threads;
 
 static struct workqueue_struct *khelper_wq;
 
+#define CAP_BSET	(void *)1
+#define CAP_PI		(void *)2
+
+static kernel_cap_t usermodehelper_bset = CAP_FULL_SET;
+static kernel_cap_t usermodehelper_inheritable = CAP_FULL_SET;
+static DEFINE_SPINLOCK(umh_sysctl_lock);
+
 #ifdef CONFIG_MODULES
 
 /*
@@ -132,6 +140,7 @@ EXPORT_SYMBOL(__request_module);
 static int ____call_usermodehelper(void *data)
 {
 	struct subprocess_info *sub_info = data;
+	struct cred *new;
 	int retval;
 
 	spin_lock_irq(&current->sighand->siglock);
@@ -153,6 +162,19 @@ static int ____call_usermodehelper(void *data)
 			goto fail;
 	}
 
+	retval = -ENOMEM;
+	new = prepare_kernel_cred(current);
+	if (!new)
+		goto fail;
+
+	spin_lock(&umh_sysctl_lock);
+	new->cap_bset = cap_intersect(usermodehelper_bset, new->cap_bset);
+	new->cap_inheritable = cap_intersect(usermodehelper_inheritable,
+					     new->cap_inheritable);
+	spin_unlock(&umh_sysctl_lock);
+
+	commit_creds(new);
+
 	retval = kernel_execve(sub_info->path,
 			       (const char *const *)sub_info->argv,
 			       (const char *const *)sub_info->envp);
@@ -420,6 +442,84 @@ unlock:
 }
 EXPORT_SYMBOL(call_usermodehelper_exec);
 
+static int proc_cap_handler(struct ctl_table *table, int write,
+			 void __user *buffer, size_t *lenp, loff_t *ppos)
+{
+	struct ctl_table t;
+	unsigned long cap_array[_KERNEL_CAPABILITY_U32S];
+	kernel_cap_t new_cap;
+	int err, i;
+
+	if (write && (!capable(CAP_SETPCAP) ||
+		      !capable(CAP_SYS_MODULE)))
+		return -EPERM;
+
+	/*
+	 * convert from the global kernel_cap_t to the ulong array to print to
+	 * userspace if this is a read.
+	 */
+	spin_lock(&umh_sysctl_lock);
+	for (i = 0; i < _KERNEL_CAPABILITY_U32S; i++)  {
+		if (table->data == CAP_BSET)
+			cap_array[i] = usermodehelper_bset.cap[i];
+		else if (table->data == CAP_PI)
+			cap_array[i] = usermodehelper_inheritable.cap[i];
+		else
+			BUG();
+	}
+	spin_unlock(&umh_sysctl_lock);
+
+	t = *table;
+	t.data = &cap_array;
+
+	/*
+	 * actually read or write and array of ulongs from userspace.  Remember
+	 * these are least significant 32 bits first
+	 */
+	err = proc_doulongvec_minmax(&t, write, buffer, lenp, ppos);
+	if (err < 0)
+		return err;
+
+	/*
+	 * convert from the sysctl array of ulongs to the kernel_cap_t
+	 * internal representation
+	 */
+	for (i = 0; i < _KERNEL_CAPABILITY_U32S; i++)
+		new_cap.cap[i] = cap_array[i];
+
+	/*
+	 * Drop everything not in the new_cap (but don't add things)
+	 */
+	spin_lock(&umh_sysctl_lock);
+	if (write) {
+		if (table->data == CAP_BSET)
+			usermodehelper_bset = cap_intersect(usermodehelper_bset, new_cap);
+		if (table->data == CAP_PI)
+			usermodehelper_inheritable = cap_intersect(usermodehelper_inheritable, new_cap);
+	}
+	spin_unlock(&umh_sysctl_lock);
+
+	return 0;
+}
+
+struct ctl_table usermodehelper_table[] = {
+	{
+		.procname	= "bset",
+		.data		= CAP_BSET,
+		.maxlen		= _KERNEL_CAPABILITY_U32S * sizeof(unsigned long),
+		.mode		= 0600,
+		.proc_handler	= proc_cap_handler,
+	},
+	{
+		.procname	= "inheritable",
+		.data		= CAP_PI,
+		.maxlen		= _KERNEL_CAPABILITY_U32S * sizeof(unsigned long),
+		.mode		= 0600,
+		.proc_handler	= proc_cap_handler,
+	},
+	{ }
+};
+
 void __init usermodehelper_init(void)
 {
 	khelper_wq = create_singlethread_workqueue("khelper");

kernel/sysctl.c

@@ -56,6 +56,7 @@
 #include <linux/kprobes.h>
 #include <linux/pipe_fs_i.h>
 #include <linux/oom.h>
+#include <linux/kmod.h>
 
 #include <asm/uaccess.h>
 #include <asm/processor.h>
@@ -615,6 +616,11 @@ static struct ctl_table kern_table[] = {
 		.mode		= 0555,
 		.child		= random_table,
 	},
+	{
+		.procname	= "usermodehelper",
+		.mode		= 0555,
+		.child		= usermodehelper_table,
+	},
 	{
 		.procname	= "overflowuid",
 		.data		= &overflowuid,