mirror of
https://github.com/torvalds/linux
synced 2024-10-04 18:33:42 +00:00
d08b9f0ca6
This change adds generic support for Clang's Shadow Call Stack, which uses a shadow stack to protect return addresses from being overwritten by an attacker. Details are available here: https://clang.llvm.org/docs/ShadowCallStack.html Note that security guarantees in the kernel differ from the ones documented for user space. The kernel must store addresses of shadow stacks in memory, which means an attacker capable reading and writing arbitrary memory may be able to locate them and hijack control flow by modifying the stacks. Signed-off-by: Sami Tolvanen <samitolvanen@google.com> Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com> [will: Numerous cosmetic changes] Signed-off-by: Will Deacon <will@kernel.org>
203 lines
5.6 KiB
C
203 lines
5.6 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
#include <linux/init_task.h>
|
|
#include <linux/export.h>
|
|
#include <linux/mqueue.h>
|
|
#include <linux/sched.h>
|
|
#include <linux/sched/sysctl.h>
|
|
#include <linux/sched/rt.h>
|
|
#include <linux/sched/task.h>
|
|
#include <linux/init.h>
|
|
#include <linux/fs.h>
|
|
#include <linux/mm.h>
|
|
#include <linux/audit.h>
|
|
#include <linux/numa.h>
|
|
#include <linux/scs.h>
|
|
|
|
#include <asm/pgtable.h>
|
|
#include <linux/uaccess.h>
|
|
|
|
static struct signal_struct init_signals = {
|
|
.nr_threads = 1,
|
|
.thread_head = LIST_HEAD_INIT(init_task.thread_node),
|
|
.wait_chldexit = __WAIT_QUEUE_HEAD_INITIALIZER(init_signals.wait_chldexit),
|
|
.shared_pending = {
|
|
.list = LIST_HEAD_INIT(init_signals.shared_pending.list),
|
|
.signal = {{0}}
|
|
},
|
|
.multiprocess = HLIST_HEAD_INIT,
|
|
.rlim = INIT_RLIMITS,
|
|
.cred_guard_mutex = __MUTEX_INITIALIZER(init_signals.cred_guard_mutex),
|
|
.exec_update_mutex = __MUTEX_INITIALIZER(init_signals.exec_update_mutex),
|
|
#ifdef CONFIG_POSIX_TIMERS
|
|
.posix_timers = LIST_HEAD_INIT(init_signals.posix_timers),
|
|
.cputimer = {
|
|
.cputime_atomic = INIT_CPUTIME_ATOMIC,
|
|
},
|
|
#endif
|
|
INIT_CPU_TIMERS(init_signals)
|
|
.pids = {
|
|
[PIDTYPE_PID] = &init_struct_pid,
|
|
[PIDTYPE_TGID] = &init_struct_pid,
|
|
[PIDTYPE_PGID] = &init_struct_pid,
|
|
[PIDTYPE_SID] = &init_struct_pid,
|
|
},
|
|
INIT_PREV_CPUTIME(init_signals)
|
|
};
|
|
|
|
static struct sighand_struct init_sighand = {
|
|
.count = REFCOUNT_INIT(1),
|
|
.action = { { { .sa_handler = SIG_DFL, } }, },
|
|
.siglock = __SPIN_LOCK_UNLOCKED(init_sighand.siglock),
|
|
.signalfd_wqh = __WAIT_QUEUE_HEAD_INITIALIZER(init_sighand.signalfd_wqh),
|
|
};
|
|
|
|
#ifdef CONFIG_SHADOW_CALL_STACK
|
|
unsigned long init_shadow_call_stack[SCS_SIZE / sizeof(long)]
|
|
__init_task_data = {
|
|
[(SCS_SIZE / sizeof(long)) - 1] = SCS_END_MAGIC
|
|
};
|
|
#endif
|
|
|
|
/*
|
|
* Set up the first task table, touch at your own risk!. Base=0,
|
|
* limit=0x1fffff (=2MB)
|
|
*/
|
|
struct task_struct init_task
|
|
#ifdef CONFIG_ARCH_TASK_STRUCT_ON_STACK
|
|
__init_task_data
|
|
#endif
|
|
= {
|
|
#ifdef CONFIG_THREAD_INFO_IN_TASK
|
|
.thread_info = INIT_THREAD_INFO(init_task),
|
|
.stack_refcount = REFCOUNT_INIT(1),
|
|
#endif
|
|
.state = 0,
|
|
.stack = init_stack,
|
|
.usage = REFCOUNT_INIT(2),
|
|
.flags = PF_KTHREAD,
|
|
.prio = MAX_PRIO - 20,
|
|
.static_prio = MAX_PRIO - 20,
|
|
.normal_prio = MAX_PRIO - 20,
|
|
.policy = SCHED_NORMAL,
|
|
.cpus_ptr = &init_task.cpus_mask,
|
|
.cpus_mask = CPU_MASK_ALL,
|
|
.nr_cpus_allowed= NR_CPUS,
|
|
.mm = NULL,
|
|
.active_mm = &init_mm,
|
|
.restart_block = {
|
|
.fn = do_no_restart_syscall,
|
|
},
|
|
.se = {
|
|
.group_node = LIST_HEAD_INIT(init_task.se.group_node),
|
|
},
|
|
.rt = {
|
|
.run_list = LIST_HEAD_INIT(init_task.rt.run_list),
|
|
.time_slice = RR_TIMESLICE,
|
|
},
|
|
.tasks = LIST_HEAD_INIT(init_task.tasks),
|
|
#ifdef CONFIG_SMP
|
|
.pushable_tasks = PLIST_NODE_INIT(init_task.pushable_tasks, MAX_PRIO),
|
|
#endif
|
|
#ifdef CONFIG_CGROUP_SCHED
|
|
.sched_task_group = &root_task_group,
|
|
#endif
|
|
.ptraced = LIST_HEAD_INIT(init_task.ptraced),
|
|
.ptrace_entry = LIST_HEAD_INIT(init_task.ptrace_entry),
|
|
.real_parent = &init_task,
|
|
.parent = &init_task,
|
|
.children = LIST_HEAD_INIT(init_task.children),
|
|
.sibling = LIST_HEAD_INIT(init_task.sibling),
|
|
.group_leader = &init_task,
|
|
RCU_POINTER_INITIALIZER(real_cred, &init_cred),
|
|
RCU_POINTER_INITIALIZER(cred, &init_cred),
|
|
.comm = INIT_TASK_COMM,
|
|
.thread = INIT_THREAD,
|
|
.fs = &init_fs,
|
|
.files = &init_files,
|
|
.signal = &init_signals,
|
|
.sighand = &init_sighand,
|
|
.nsproxy = &init_nsproxy,
|
|
.pending = {
|
|
.list = LIST_HEAD_INIT(init_task.pending.list),
|
|
.signal = {{0}}
|
|
},
|
|
.blocked = {{0}},
|
|
.alloc_lock = __SPIN_LOCK_UNLOCKED(init_task.alloc_lock),
|
|
.journal_info = NULL,
|
|
INIT_CPU_TIMERS(init_task)
|
|
.pi_lock = __RAW_SPIN_LOCK_UNLOCKED(init_task.pi_lock),
|
|
.timer_slack_ns = 50000, /* 50 usec default slack */
|
|
.thread_pid = &init_struct_pid,
|
|
.thread_group = LIST_HEAD_INIT(init_task.thread_group),
|
|
.thread_node = LIST_HEAD_INIT(init_signals.thread_head),
|
|
#ifdef CONFIG_AUDIT
|
|
.loginuid = INVALID_UID,
|
|
.sessionid = AUDIT_SID_UNSET,
|
|
#endif
|
|
#ifdef CONFIG_PERF_EVENTS
|
|
.perf_event_mutex = __MUTEX_INITIALIZER(init_task.perf_event_mutex),
|
|
.perf_event_list = LIST_HEAD_INIT(init_task.perf_event_list),
|
|
#endif
|
|
#ifdef CONFIG_PREEMPT_RCU
|
|
.rcu_read_lock_nesting = 0,
|
|
.rcu_read_unlock_special.s = 0,
|
|
.rcu_node_entry = LIST_HEAD_INIT(init_task.rcu_node_entry),
|
|
.rcu_blocked_node = NULL,
|
|
#endif
|
|
#ifdef CONFIG_TASKS_RCU
|
|
.rcu_tasks_holdout = false,
|
|
.rcu_tasks_holdout_list = LIST_HEAD_INIT(init_task.rcu_tasks_holdout_list),
|
|
.rcu_tasks_idle_cpu = -1,
|
|
#endif
|
|
#ifdef CONFIG_CPUSETS
|
|
.mems_allowed_seq = SEQCNT_ZERO(init_task.mems_allowed_seq),
|
|
#endif
|
|
#ifdef CONFIG_RT_MUTEXES
|
|
.pi_waiters = RB_ROOT_CACHED,
|
|
.pi_top_task = NULL,
|
|
#endif
|
|
INIT_PREV_CPUTIME(init_task)
|
|
#ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
|
|
.vtime.seqcount = SEQCNT_ZERO(init_task.vtime_seqcount),
|
|
.vtime.starttime = 0,
|
|
.vtime.state = VTIME_SYS,
|
|
#endif
|
|
#ifdef CONFIG_NUMA_BALANCING
|
|
.numa_preferred_nid = NUMA_NO_NODE,
|
|
.numa_group = NULL,
|
|
.numa_faults = NULL,
|
|
#endif
|
|
#ifdef CONFIG_KASAN
|
|
.kasan_depth = 1,
|
|
#endif
|
|
#ifdef CONFIG_TRACE_IRQFLAGS
|
|
.softirqs_enabled = 1,
|
|
#endif
|
|
#ifdef CONFIG_LOCKDEP
|
|
.lockdep_depth = 0, /* no locks held yet */
|
|
.curr_chain_key = INITIAL_CHAIN_KEY,
|
|
.lockdep_recursion = 0,
|
|
#endif
|
|
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
|
|
.ret_stack = NULL,
|
|
#endif
|
|
#if defined(CONFIG_TRACING) && defined(CONFIG_PREEMPTION)
|
|
.trace_recursion = 0,
|
|
#endif
|
|
#ifdef CONFIG_LIVEPATCH
|
|
.patch_state = KLP_UNDEFINED,
|
|
#endif
|
|
#ifdef CONFIG_SECURITY
|
|
.security = NULL,
|
|
#endif
|
|
};
|
|
EXPORT_SYMBOL(init_task);
|
|
|
|
/*
|
|
* Initial thread structure. Alignment of this is handled by a special
|
|
* linker map entry.
|
|
*/
|
|
#ifndef CONFIG_THREAD_INFO_IN_TASK
|
|
struct thread_info init_thread_info __init_thread_info = INIT_THREAD_INFO(init_task);
|
|
#endif
|