seccomp: extract check/assign mode helpers

To support splitting mode 1 from mode 2, extract the mode checking and
assignment logic into common functions.

Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Andy Lutomirski <luto@amacapital.net>
This commit is contained in:
Kees Cook 2014-06-25 15:38:02 -07:00
parent d78ab02c2c
commit 1f41b45041

View File

@ -194,7 +194,23 @@ static u32 seccomp_run_filters(int syscall)
}
return ret;
}
#endif /* CONFIG_SECCOMP_FILTER */
static inline bool seccomp_may_assign_mode(unsigned long seccomp_mode)
{
if (current->seccomp.mode && current->seccomp.mode != seccomp_mode)
return false;
return true;
}
static inline void seccomp_assign_mode(unsigned long seccomp_mode)
{
current->seccomp.mode = seccomp_mode;
set_tsk_thread_flag(current, TIF_SECCOMP);
}
#ifdef CONFIG_SECCOMP_FILTER
/**
* seccomp_attach_filter: Attaches a seccomp filter to current.
* @fprog: BPF program to install
@ -490,8 +506,7 @@ static long seccomp_set_mode(unsigned long seccomp_mode, char __user *filter)
{
long ret = -EINVAL;
if (current->seccomp.mode &&
current->seccomp.mode != seccomp_mode)
if (!seccomp_may_assign_mode(seccomp_mode))
goto out;
switch (seccomp_mode) {
@ -512,8 +527,7 @@ static long seccomp_set_mode(unsigned long seccomp_mode, char __user *filter)
goto out;
}
current->seccomp.mode = seccomp_mode;
set_thread_flag(TIF_SECCOMP);
seccomp_assign_mode(seccomp_mode);
out:
return ret;
}