Creds: creds->security can be NULL is selinux is disabled

__validate_process_creds should check if selinux is actually enabled before
running tests on the selinux portion of the credentials struct.

Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
This commit is contained in:
Eric Paris 2009-09-12 22:54:10 -04:00 committed by James Morris
parent 86d710146f
commit ed868a5698
3 changed files with 23 additions and 5 deletions

View File

@ -15,6 +15,7 @@
#include <linux/capability.h>
#include <linux/init.h>
#include <linux/key.h>
#include <linux/selinux.h>
#include <asm/atomic.h>
struct user_struct;
@ -182,11 +183,13 @@ static inline bool creds_are_invalid(const struct cred *cred)
if (atomic_read(&cred->usage) < atomic_read(&cred->subscribers))
return true;
#ifdef CONFIG_SECURITY_SELINUX
if ((unsigned long) cred->security < PAGE_SIZE)
return true;
if ((*(u32*)cred->security & 0xffffff00) ==
(POISON_FREE << 24 | POISON_FREE << 16 | POISON_FREE << 8))
return true;
if (selinux_is_enabled()) {
if ((unsigned long) cred->security < PAGE_SIZE)
return true;
if ((*(u32 *)cred->security & 0xffffff00) ==
(POISON_FREE << 24 | POISON_FREE << 16 | POISON_FREE << 8))
return true;
}
#endif
return false;
}

View File

@ -61,6 +61,11 @@ void selinux_secmark_refcount_inc(void);
* existing SECMARK targets has been removed/flushed.
*/
void selinux_secmark_refcount_dec(void);
/**
* selinux_is_enabled - is SELinux enabled?
*/
bool selinux_is_enabled(void);
#else
static inline int selinux_string_to_sid(const char *str, u32 *sid)
@ -84,6 +89,10 @@ static inline void selinux_secmark_refcount_dec(void)
return;
}
static bool selinux_is_enabled(void)
{
return false;
}
#endif /* CONFIG_SECURITY_SELINUX */
#endif /* _LINUX_SELINUX_H */

View File

@ -63,3 +63,9 @@ void selinux_secmark_refcount_dec(void)
atomic_dec(&selinux_secmark_refcount);
}
EXPORT_SYMBOL_GPL(selinux_secmark_refcount_dec);
bool selinux_is_enabled(void)
{
return selinux_enabled;
}
EXPORT_SYMBOL_GPL(selinux_is_enabled);