Signed-off-by: Alexey Dobriyan <adobriyan@xxxxxxxxx>
---
arch/x86/include/asm/signal.h | 2 +
include/linux/kstate-image.h | 17 +++++
include/linux/kstate.h | 29 ++++++++
kernel/kstate/cpt-sys.c | 6 ++
kernel/kstate/kstate-context.c | 5 ++
kernel/kstate/kstate-object.c | 3 +
kernel/kstate/kstate-task.c | 32 +++++++++
kernel/signal.c | 140 ++++++++++++++++++++++++++++++++++++++++
8 files changed, 234 insertions(+), 0 deletions(-)
diff --git a/arch/x86/include/asm/signal.h b/arch/x86/include/asm/signal.h
index 7761a5d..f7c9040 100644
--- a/arch/x86/include/asm/signal.h
+++ b/arch/x86/include/asm/signal.h
@@ -140,6 +140,7 @@ struct sigaction {
__sigrestore_t sa_restorer;
sigset_t sa_mask; /* mask last for extensibility */
};
+#define sa_restorer sa_restorer
struct k_sigaction {
struct sigaction sa;
@@ -170,6 +171,7 @@ struct sigaction {
__sigrestore_t sa_restorer;
sigset_t sa_mask; /* mask last for extensibility */
};
+#define sa_restorer sa_restorer
struct k_sigaction {
struct sigaction sa;
diff --git a/include/linux/kstate-image.h b/include/linux/kstate-image.h
index 700fc62..38fb1a4 100644
--- a/include/linux/kstate-image.h
+++ b/include/linux/kstate-image.h
@@ -18,6 +18,9 @@ static inline int kstate_ref_undefined(kstate_ref_t *ref)
return ref->pos == 0 && ref->id == 0;
}
+typedef __u8 kstate_sigset_t[16];
+typedef __u64 kstate_ptr_t;
+
struct kstate_image_header {
/* Immutable part except version bumps. */
#define KSTATE_IMAGE_MAGIC "LinuxC/R"
@@ -56,6 +59,7 @@ struct kstate_image_header {
#define KSTATE_OBJ_PID 16
#define KSTATE_OBJ_FILES_STRUCT 17
#define KSTATE_OBJ_FD 18
+#define KSTATE_OBJ_SIGHAND_STRUCT 19
struct kstate_object_header {
__u32 obj_type;
@@ -88,6 +92,8 @@ struct kstate_image_task_struct {
kstate_ref_t ref_pgid;
kstate_ref_t ref_sid;
+ kstate_ref_t ref_sighand;
+
__u8 comm[16];
/* Native arch of task, one of KSTATE_ARCH_*. */
@@ -334,4 +340,15 @@ struct kstate_image_fd {
#define KSTATE_FD_FLAGS_CLOEXEC (1 << 0)
__u32 fd_flags;
} __packed;
+
+struct kstate_image_sighand_struct {
+ struct kstate_object_header hdr;
+
+ struct {
+ kstate_ptr_t sa_handler;
+ __u64 sa_flags;
+ kstate_ptr_t sa_restorer;
+ kstate_sigset_t sa_mask;
+ } sa[128];
+} __packed;
#endif
diff --git a/include/linux/kstate.h b/include/linux/kstate.h
index 2473381..c958d1d 100644
--- a/include/linux/kstate.h
+++ b/include/linux/kstate.h
@@ -1,7 +1,9 @@
/* Copyright (C) 2000-2009 Parallels Holdings, Ltd. */
#ifndef __INCLUDE_LINUX_KSTATE_H
#define __INCLUDE_LINUX_KSTATE_H
+#include <linux/compiler.h>
#include <linux/list.h>
+#include <asm/signal.h>
#include <linux/kstate-image.h>
@@ -36,6 +38,7 @@ enum kstate_context_obj_type {
KSTATE_CTX_NSPROXY,
KSTATE_CTX_PID,
KSTATE_CTX_PID_NS,
+ KSTATE_CTX_SIGHAND_STRUCT,
KSTATE_CTX_TASK_STRUCT,
KSTATE_CTX_USER_NS,
KSTATE_CTX_USER_STRUCT,
@@ -70,6 +73,28 @@ void *kstate_prepare_image(__u32 type, unsigned int len);
void *kstate_read_image(struct kstate_context *ctx, kstate_ref_t *ref, __u32 type, unsigned int len);
int kstate_write_image(struct kstate_context *ctx, void *i, unsigned int len, struct kstate_object *obj);
+static inline kstate_ptr_t kstate_export_ptr(const void __user *ptr)
+{
+ BUILD_BUG_ON(sizeof(kstate_ptr_t) < sizeof(ptr));
+ return (unsigned long)ptr;
+}
+
+static inline const void __user *kstate_import_ptr(kstate_ptr_t i)
+{
+ return (const void __user *)(unsigned long)i;
+}
+
+static inline void kstate_dump_sigset(kstate_sigset_t *i, sigset_t *sig)
+{
+ BUILD_BUG_ON(sizeof(sigset_t) > sizeof(kstate_sigset_t));
+ memcpy(i, sig, sizeof(sigset_t));
+}
+
+static inline void kstate_restore_sigset(sigset_t *sig, kstate_sigset_t *i)
+{
+ memcpy(sig, i, sizeof(sigset_t));
+}
+
int kstate_collect_all_task_struct(struct kstate_context *ctx);
int kstate_dump_all_task_struct(struct kstate_context *ctx);
int kstate_restore_task_struct(struct kstate_context *ctx, kstate_ref_t *ref);
@@ -155,6 +180,10 @@ int kstate_dump_all_files_struct(struct kstate_context *ctx);
int kstate_restore_files_struct(struct kstate_context *ctx, kstate_ref_t *ref);
int kstate_restore_fd(struct kstate_context *ctx, kstate_pos_t pos);
+int kstate_collect_all_sighand_struct(struct kstate_context *ctx);
+int kstate_dump_all_sighand_struct(struct kstate_context *ctx);
+int kstate_restore_sighand_struct(struct kstate_context *ctx, kstate_ref_t *ref);
+
#if defined(CONFIG_X86_32) || defined(CONFIG_X86_64)
extern const __u32 kstate_kernel_arch;
int kstate_arch_check_image_header(struct kstate_image_header *i);
diff --git a/kernel/kstate/cpt-sys.c b/kernel/kstate/cpt-sys.c
index 05fc9d8..8225804 100644
--- a/kernel/kstate/cpt-sys.c
+++ b/kernel/kstate/cpt-sys.c
@@ -104,6 +104,9 @@ static int kstate_collect(struct kstate_context *ctx)
rv = kstate_collect_all_user_ns(ctx);
if (rv < 0)
return rv;
+ rv = kstate_collect_all_sighand_struct(ctx);
+ if (rv < 0)
+ return rv;
rv = kstate_collect_all_pid(ctx);
if (rv < 0)
return rv;
@@ -163,6 +166,9 @@ static int kstate_dump(struct kstate_context *ctx)
rv = kstate_dump_all_pid(ctx);
if (rv < 0)
return rv;
+ rv = kstate_dump_all_sighand_struct(ctx);
+ if (rv < 0)
+ return rv;
rv = kstate_dump_all_user_ns(ctx);
if (rv < 0)
return rv;
diff --git a/kernel/kstate/kstate-context.c b/kernel/kstate/kstate-context.c
index 3e1589f..44111d1 100644
--- a/kernel/kstate/kstate-context.c
+++ b/kernel/kstate/kstate-context.c
@@ -97,6 +97,11 @@ void kstate_context_destroy(struct kstate_context *ctx)
list_del(&obj->o_list);
kfree(obj);
}
+ for_each_kstate_object_safe(ctx, obj, tmp, KSTATE_CTX_SIGHAND_STRUCT) {
+ __cleanup_sighand((struct sighand_struct *)obj->o_obj);
+ list_del(&obj->o_list);
+ kfree(obj);
+ }
for_each_kstate_object_safe(ctx, obj, tmp, KSTATE_CTX_TASK_STRUCT) {
put_task_struct((struct task_struct *)obj->o_obj);
list_del(&obj->o_list);
diff --git a/kernel/kstate/kstate-object.c b/kernel/kstate/kstate-object.c
index bc27985..f871463 100644
--- a/kernel/kstate/kstate-object.c
+++ b/kernel/kstate/kstate-object.c
@@ -74,6 +74,9 @@ int kstate_collect_object(struct kstate_context *ctx, void *p, enum kstate_conte
case KSTATE_CTX_PID_NS:
get_pid_ns((struct pid_namespace *)obj->o_obj);
break;
+ case KSTATE_CTX_SIGHAND_STRUCT:
+ atomic_inc(&((struct sighand_struct *)obj->o_obj)->count);
+ break;
case KSTATE_CTX_TASK_STRUCT:
get_task_struct((struct task_struct *)obj->o_obj);
break;
diff --git a/kernel/kstate/kstate-task.c b/kernel/kstate/kstate-task.c
index 101fcb8..2cfcb8f 100644
--- a/kernel/kstate/kstate-task.c
+++ b/kernel/kstate/kstate-task.c
@@ -139,6 +139,9 @@ static int dump_task_struct(struct kstate_context *ctx, struct kstate_object *ob
tmp = find_kstate_obj_by_ptr(ctx, tsk->files, KSTATE_CTX_FILES_STRUCT);
i->ref_files = tmp->o_ref;
+ tmp = find_kstate_obj_by_ptr(ctx, tsk->sighand, KSTATE_CTX_SIGHAND_STRUCT);
+ i->ref_sighand = tmp->o_ref;
+
BUILD_BUG_ON(sizeof(i->comm) != sizeof(tsk->comm));
strlcpy((char *)i->comm, (const char *)tsk->comm, sizeof(i->comm));
@@ -402,6 +405,32 @@ static int restore_files(struct kstate_context *ctx, kstate_ref_t *ref)
return 0;
}
+static int restore_sighand(struct kstate_context *ctx, kstate_ref_t *ref)
+{
+ struct sighand_struct *sighand;
+ struct kstate_object *tmp;
+ struct sighand_struct *old_sighand;
+ unsigned long flags;
+ int rv;
+
+ tmp = find_kstate_obj_by_ref(ctx, ref, KSTATE_CTX_SIGHAND_STRUCT);
+ if (!tmp) {
+ rv = kstate_restore_sighand_struct(ctx, ref);
+ if (rv < 0)
+ return rv;
+ tmp = find_kstate_obj_by_ref(ctx, ref, KSTATE_CTX_SIGHAND_STRUCT);
+ }
+ sighand = tmp->o_obj;
+
+ atomic_inc(&sighand->count);
+ old_sighand = current->sighand;
+ spin_lock_irqsave(&old_sighand->siglock, flags);
+ current->sighand = sighand;
+ spin_unlock_irqrestore(&old_sighand->siglock, flags);
+ __cleanup_sighand(old_sighand);
+ return 0;
+}
+
struct task_struct_restore_context {
struct kstate_context *ctx;
struct kstate_image_task_struct *i;
@@ -468,6 +497,9 @@ static int task_struct_restorer(void *_tsk_ctx)
rv = restore_files(ctx, &i->ref_files);
if (rv < 0)
goto out;
+ rv = restore_sighand(ctx, &i->ref_sighand);
+ if (rv < 0)
+ goto out;
out:
tsk_ctx->rv = rv;
diff --git a/kernel/signal.c b/kernel/signal.c
index d803473..5d5dc13 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -2,6 +2,7 @@
* linux/kernel/signal.c
*
* Copyright (C) 1991, 1992 Linus Torvalds
+ * Copyright (C) 2000-2009 Parallels Holdings, Ltd.
*
* 1997-11-02 Modified for POSIX.1b signals by Richard Henderson
*
@@ -2656,3 +2657,142 @@ void __init signals_init(void)
{
sigqueue_cachep = KMEM_CACHE(sigqueue, SLAB_PANIC);
}
+
+#ifdef CONFIG_CHECKPOINT
+#include <linux/kstate.h>
+#include <linux/kstate-image.h>
+
+static int check_sighand_struct(struct sighand_struct *sighand)
+{
+#ifdef CONFIG_SIGNALFD
+ if (waitqueue_active(&sighand->signalfd_wqh)) {
+ WARN_ON(1);
+ return -EINVAL;
+ }
+#endif
+ return 0;
+}
+
+static int collect_sighand_struct(struct kstate_context *ctx, struct sighand_struct *sighand)
+{
+ int rv;
+
+ rv = check_sighand_struct(sighand);
+ if (rv < 0)
+ return rv;
+ rv = kstate_collect_object(ctx, sighand, KSTATE_CTX_SIGHAND_STRUCT);
+ pr_debug("collect sighand_struct %p: rv %d\n", sighand, rv);
+ return rv;
+}
+
+int kstate_collect_all_sighand_struct(struct kstate_context *ctx)
+{
+ struct kstate_object *obj;
+ int rv;
+
+ for_each_kstate_object(ctx, obj, KSTATE_CTX_TASK_STRUCT) {
+ struct task_struct *tsk = obj->o_obj;
+
+ rv = collect_sighand_struct(ctx, tsk->sighand);
+ if (rv < 0)
+ return rv;
+ }
+ for_each_kstate_object(ctx, obj, KSTATE_CTX_SIGHAND_STRUCT) {
+ struct sighand_struct *sighand = obj->o_obj;
+ unsigned int cnt = atomic_read(&sighand->count);
+
+ if (obj->o_count + 1 != cnt) {
+ pr_err("sighand_struct %p has external references %lu:%u\n", sighand, obj->o_count, cnt);
+ return -EINVAL;
+ }
+ }
+ return 0;
+}
+
+static int dump_sighand_struct(struct kstate_context *ctx, struct kstate_object *obj)
+{
+ struct sighand_struct *sighand = obj->o_obj;
+ struct kstate_image_sighand_struct *i;
+ unsigned long flags;
+ int sig;
+ int rv;
+
+ i = kstate_prepare_image(KSTATE_OBJ_SIGHAND_STRUCT, sizeof(*i));
+ if (!i)
+ return -ENOMEM;
+
+ BUILD_BUG_ON(_NSIG > ARRAY_SIZE(i->sa));
+ spin_lock_irqsave(&sighand->siglock, flags);
+ for (sig = 0; sig < _NSIG; sig++) {
+ struct sigaction *sa = &sighand->action[sig].sa;
+
+ i->sa[sig].sa_handler = kstate_export_ptr(sa->sa_handler);
+ i->sa[sig].sa_flags = sa->sa_flags;
+#ifdef sa_restorer
+ i->sa[sig].sa_restorer = kstate_export_ptr(sa->sa_restorer);
+#endif
+ kstate_dump_sigset(&i->sa[sig].sa_mask, &sa->sa_mask);
+ }
+ spin_unlock_irqrestore(&sighand->siglock, flags);
+
+ rv = kstate_write_image(ctx, i, sizeof(*i), obj);
+ kfree(i);
+ pr_debug("dump sighand_struct %p: ref {%llu, %u}, rv %d\n", sighand, (unsigned long long)obj->o_ref.pos, obj->o_ref.id, rv);
+ return rv;
+}
+
+int kstate_dump_all_sighand_struct(struct kstate_context *ctx)
+{
+ struct kstate_object *obj;
+ int rv;
+
+ for_each_kstate_object(ctx, obj, KSTATE_CTX_SIGHAND_STRUCT) {
+ rv = dump_sighand_struct(ctx, obj);
+ if (rv < 0)
+ return rv;
+ }
+ return 0;
+}
+
+int kstate_restore_sighand_struct(struct kstate_context *ctx, kstate_ref_t *ref)
+{
+ struct kstate_image_sighand_struct *i;
+ struct sighand_struct *sighand;
+ int sig;
+ int rv;
+
+ i = kstate_read_image(ctx, ref, KSTATE_OBJ_SIGHAND_STRUCT, sizeof(*i));
+ if (IS_ERR(i))
+ return PTR_ERR(i);
+
+ sighand = kmem_cache_alloc(sighand_cachep, GFP_KERNEL);
+ if (!sighand) {
+ rv = -ENOMEM;
+ goto out_free_image;
+ }
+ atomic_set(&sighand->count, 1);
+
+ for (sig = 0; sig < _NSIG; sig++) {
+ struct sigaction *sa = &sighand->action[sig].sa;
+
+ sa->sa_handler = kstate_import_ptr(i->sa[sig].sa_handler);
+ sa->sa_flags = i->sa[sig].sa_flags;
+#ifdef sa_restorer
+ sa->sa_restorer = kstate_import_ptr(i->sa[sig].sa_restorer);
+#endif
+ kstate_restore_sigset(&sa->sa_mask, &i->sa[sig].sa_mask);
+ }
+ kfree(i);
+
+ rv = kstate_restore_object(ctx, sighand, KSTATE_CTX_SIGHAND_STRUCT, ref);
+ if (rv < 0)
+ kmem_cache_free(sighand_cachep, sighand);
+ pr_debug("restore sighand_struct %p: ref {%llu, %u}, rv %d\n", sighand, (unsigned long long)ref->pos, ref->id, rv);
+ return rv;
+
+out_free_image:
+ kfree(i);
+ pr_debug("%s: return %d, ref {%llu, %u}\n", __func__, rv, (unsigned long long)ref->pos, ref->id);
+ return rv;
+}
+#endif
--
1.5.6.5
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