C/R tsk->files and opened files!
fd should have struct file::checkpoint ;-)
Signed-off-by: Alexey Dobriyan <adobriyan@xxxxxxxxx>
---
include/linux/cr.h | 16 +++
kernel/cr/cpt-sys.c | 6 +
kernel/cr/cr-file.c | 249 ++++++++++++++++++++++++++++++++++++++++++++++++++++
kernel/cr/cr-task.c | 5 +
kernel/cr/cr.h | 4
5 files changed, 280 insertions(+)
--- a/include/linux/cr.h
+++ b/include/linux/cr.h
@@ -39,6 +39,8 @@ struct cr_object_header {
#define CR_OBJ_UTS_NS 8
#define CR_OBJ_PID_NS 9
#define CR_OBJ_PID 10
+#define CR_OBJ_FILES_STRUCT 11
+#define CR_OBJ_FD 12
__u32 cr_type; /* object type */
__u32 cr_len; /* object length in bytes including header */
} __packed;
@@ -59,6 +61,7 @@ struct cr_image_task_struct {
cr_pos_t cr_pos_real_parent;
cr_pos_t cr_pos_mm;
cr_pos_t cr_pos_pids[3];
+ cr_pos_t cr_pos_files;
cr_pos_t cr_pos_nsproxy;
__u8 cr_comm[16];
@@ -228,6 +231,10 @@ struct cr_image_vma_content {
/* __u8 cr_data[cr_nr_pages * cr_page_size]; */
} __packed;
+struct cr_image_files_struct {
+ struct cr_object_header cr_hdr;
+} __packed;
+
struct cr_image_file {
struct cr_object_header cr_hdr;
@@ -245,6 +252,15 @@ struct cr_image_file {
/* __u8 cr_name[cr_name_len] */
} __packed;
+struct cr_image_fd {
+ struct cr_object_header cr_hdr;
+
+ cr_pos_t cr_pos_file;
+ __u32 cr_fd;
+#define CR_FD_FLAGS_CLOEXEC (1 << 0)
+ __u32 cr_fd_flags;
+} __packed;
+
struct cr_image_pid {
struct cr_object_header cr_hdr;
--- a/kernel/cr/cpt-sys.c
+++ b/kernel/cr/cpt-sys.c
@@ -77,6 +77,9 @@ static int cr_collect(struct cr_context *ctx)
rv = cr_collect_all_mm_struct(ctx);
if (rv < 0)
return rv;
+ rv = cr_collect_all_files_struct(ctx);
+ if (rv < 0)
+ return rv;
rv = cr_collect_all_file(ctx);
if (rv < 0)
return rv;
@@ -125,6 +128,9 @@ static int cr_dump(struct cr_context *ctx)
rv = cr_dump_all_file(ctx);
if (rv < 0)
return rv;
+ rv = cr_dump_all_files_struct(ctx);
+ if (rv < 0)
+ return rv;
rv = cr_dump_all_uts_ns(ctx);
if (rv < 0)
return rv;
--- a/kernel/cr/cr-file.c
+++ b/kernel/cr/cr-file.c
@@ -64,6 +64,20 @@ int cr_collect_all_file(struct cr_context *ctx)
struct cr_object *obj;
int rv;
+ for_each_cr_object(ctx, obj, CR_CTX_FILES_STRUCT) {
+ struct files_struct *files = obj->o_obj;
+ struct file *file;
+ int fd;
+
+ for (fd = 0; fd < files->fdt->max_fds; fd++) {
+ file = fcheck_files(files, fd);
+ if (!file)
+ continue;
+ rv = cr_collect_file(ctx, file);
+ if (rv < 0)
+ return rv;
+ }
+ }
for_each_cr_object(ctx, obj, CR_CTX_MM_STRUCT) {
struct mm_struct *mm = obj->o_obj;
struct vm_area_struct *vma;
@@ -229,3 +243,238 @@ int cr_restore_file(struct cr_context *ctx, loff_t pos)
kfree(i);
return 0;
}
+
+static int cr_restore_fd(struct cr_context *ctx, loff_t pos)
+{
+ struct cr_image_fd *i;
+ struct file *file;
+ int fd;
+ unsigned int flags;
+ struct cr_object *tmp;
+ int rv;
+
+ i = kzalloc(sizeof(*i), GFP_KERNEL);
+ if (!i)
+ return -ENOMEM;
+ rv = cr_pread(ctx, i, sizeof(*i), pos);
+ if (rv < 0) {
+ kfree(i);
+ return rv;
+ }
+ if (i->cr_hdr.cr_type != CR_OBJ_FD) {
+ kfree(i);
+ return -EINVAL;
+ }
+
+ tmp = cr_find_obj_by_pos(ctx, i->cr_pos_file, CR_CTX_FILE);
+ if (!tmp) {
+ rv = cr_restore_file(ctx, i->cr_pos_file);
+ if (rv < 0) {
+ kfree(i);
+ return rv;
+ }
+ tmp = cr_find_obj_by_pos(ctx, i->cr_pos_file, CR_CTX_FILE);
+ }
+ file = tmp->o_obj;
+
+ flags = 0;
+ if (i->cr_fd_flags & CR_FD_FLAGS_CLOEXEC)
+ flags |= O_CLOEXEC;
+ fd = alloc_fd(i->cr_fd, flags);
+ if (fd != i->cr_fd)
+ rv = (fd < 0) ? fd : -EINVAL;
+ else
+ rv = 0;
+ kfree(i);
+ if (rv < 0)
+ return rv;
+
+ get_file(file);
+ fd_install(fd, file);
+ return 0;
+}
+
+static int cr_restore_all_fd(struct cr_context *ctx, loff_t pos)
+{
+ struct cr_object_header cr_hdr;
+ int rv;
+
+ while (1) {
+ rv = cr_pread(ctx, &cr_hdr, sizeof(cr_hdr), pos);
+ if (rv < 0)
+ return rv;
+ if (cr_hdr.cr_type == CR_OBJ_FD) {
+ rv = cr_restore_fd(ctx, pos);
+ if (rv < 0)
+ return rv;
+ } else
+ return 0;
+ pos += cr_hdr.cr_len;
+ }
+}
+
+static int cr_collect_files_struct(struct cr_context *ctx, struct files_struct *files)
+{
+ int rv;
+
+ rv = cr_collect_object(ctx, files, CR_CTX_FILES_STRUCT);
+ printk("collect files_struct %p: rv %d\n", files, rv);
+ return rv;
+}
+
+int cr_collect_all_files_struct(struct cr_context *ctx)
+{
+ struct cr_object *obj;
+ int rv;
+
+ for_each_cr_object(ctx, obj, CR_CTX_TASK_STRUCT) {
+ struct task_struct *tsk = obj->o_obj;
+
+ rv = cr_collect_files_struct(ctx, tsk->files);
+ if (rv < 0)
+ return rv;
+ }
+ for_each_cr_object(ctx, obj, CR_CTX_FILES_STRUCT) {
+ struct files_struct *files = obj->o_obj;
+ unsigned int cnt = atomic_read(&files->count);
+
+ if (obj->o_count != cnt) {
+ printk("%s: files_struct %p has external references %lu:%u\n", __func__, files, obj->o_count, cnt);
+ return -EINVAL;
+ }
+ }
+ return 0;
+}
+
+static int cr_dump_fd(struct cr_context *ctx, struct files_struct *files, int fd, struct file *file)
+{
+ struct cr_image_fd *i;
+ struct cr_object *tmp;
+ int rv;
+
+ printk("dump fd %d, files_struct = %p, file = %p\n", fd, files, file);
+
+ i = cr_prepare_image(CR_OBJ_FD, sizeof(*i));
+ if (!i)
+ return -ENOMEM;
+
+ tmp = cr_find_obj_by_ptr(ctx, file, CR_CTX_FILE);
+ i->cr_pos_file = tmp->o_pos;
+ i->cr_fd = fd;
+ i->cr_fd_flags = 0;
+ if (FD_ISSET(fd, files->fdt->close_on_exec))
+ i->cr_fd_flags |= CR_FD_FLAGS_CLOEXEC;
+
+ rv = cr_write(ctx, i, sizeof(*i));
+ kfree(i);
+ return rv;
+}
+
+static int cr_dump_files_struct(struct cr_context *ctx, struct cr_object *obj)
+{
+ struct files_struct *files = obj->o_obj;
+ struct cr_image_files_struct *i;
+ int fd;
+ int rv;
+
+ printk("dump files_struct %p\n", files);
+
+ i = cr_prepare_image(CR_OBJ_FILES_STRUCT, sizeof(*i));
+ if (!i)
+ return -ENOMEM;
+
+ obj->o_pos = ctx->cr_dump_file->f_pos;
+ rv = cr_write(ctx, i, sizeof(*i));
+ kfree(i);
+ if (rv < 0)
+ return rv;
+
+ for (fd = 0; fd < files->fdt->max_fds; fd++) {
+ struct file *file;
+
+ file = fcheck_files(files, fd);
+ if (file) {
+ rv = cr_dump_fd(ctx, files, fd, file);
+ if (rv < 0)
+ return rv;
+ }
+ }
+ return 0;
+}
+
+int cr_dump_all_files_struct(struct cr_context *ctx)
+{
+ struct cr_object *obj;
+ int rv;
+
+ for_each_cr_object(ctx, obj, CR_CTX_FILES_STRUCT) {
+ rv = cr_dump_files_struct(ctx, obj);
+ if (rv < 0)
+ return rv;
+ }
+ return 0;
+}
+
+static int __cr_restore_files_struct(struct cr_context *ctx, loff_t pos)
+{
+ struct cr_image_files_struct *i;
+ struct files_struct *files;
+ struct cr_object *obj;
+ int rv;
+
+ i = kzalloc(sizeof(*i), GFP_KERNEL);
+ if (!i)
+ return -ENOMEM;
+ rv = cr_pread(ctx, i, sizeof(*i), pos);
+ if (rv < 0) {
+ kfree(i);
+ return rv;
+ }
+ if (i->cr_hdr.cr_type != CR_OBJ_FILES_STRUCT) {
+ kfree(i);
+ return -EINVAL;
+ }
+
+ files = kmem_cache_zalloc(files_cachep, GFP_KERNEL);
+ if (!files) {
+ kfree(i);
+ return -ENOMEM;
+ }
+ atomic_set(&files->count, 1);
+ files->fdt = &files->fdtab;
+ files->fdt->max_fds = NR_OPEN_DEFAULT;
+ files->fdt->fd = files->fd_array;
+ files->fdt->close_on_exec = (fd_set *)&files->close_on_exec_init;
+ files->fdt->open_fds = (fd_set *)&files->open_fds_init;
+ spin_lock_init(&files->file_lock);
+ kfree(i);
+
+ obj = cr_object_create(files);
+ if (!obj) {
+ kmem_cache_free(files_cachep, files);
+ return -ENOMEM;
+ }
+ obj->o_pos = pos;
+ list_add(&obj->o_list, &ctx->cr_obj[CR_CTX_FILES_STRUCT]);
+ printk("restore files_struct %p, pos %lld\n", files, (long long)pos);
+ return 0;
+}
+
+int cr_restore_files_struct(struct cr_context *ctx, loff_t pos)
+{
+ struct files_struct *files;
+ struct cr_object *tmp;
+ int rv;
+
+ tmp = cr_find_obj_by_pos(ctx, pos, CR_CTX_FILES_STRUCT);
+ if (!tmp) {
+ rv = __cr_restore_files_struct(ctx, pos);
+ if (rv < 0)
+ return rv;
+ tmp = cr_find_obj_by_pos(ctx, pos, CR_CTX_FILES_STRUCT);
+ }
+ files = tmp->o_obj;
+ atomic_inc(&files->count);
+ reset_files_struct(files);
+ return cr_restore_all_fd(ctx, pos + sizeof(struct cr_image_files_struct));
+}
--- a/kernel/cr/cr-task.c
+++ b/kernel/cr/cr-task.c
@@ -127,6 +127,8 @@ static int cr_dump_task_struct(struct cr_context *ctx, struct cr_object *obj)
i->cr_pos_pids[2] = tmp->o_pos;
else
i->cr_pos_pids[2] = CR_POS_UNDEF;
+ tmp = cr_find_obj_by_ptr(ctx, tsk->files, CR_CTX_FILES_STRUCT);
+ i->cr_pos_files = tmp->o_pos;
BUILD_BUG_ON(TASK_COMM_LEN != 16);
strlcpy((char *)i->cr_comm, (const char *)tsk->comm, sizeof(i->cr_comm));
@@ -186,6 +188,9 @@ static int task_struct_restorer(void *_tsk_ctx)
rv = cr_restore_nsproxy(ctx, i->cr_pos_nsproxy);
if (rv < 0)
goto out;
+ rv = cr_restore_files_struct(ctx, i->cr_pos_files);
+ if (rv < 0)
+ return rv;
rv = cr_restore_pid(ctx, i);
if (rv < 0)
goto out;
--- a/kernel/cr/cr.h
+++ b/kernel/cr/cr.h
@@ -23,6 +23,7 @@ struct cr_object {
/* Not visible to userspace! */
enum cr_context_obj_type {
CR_CTX_FILE,
+ CR_CTX_FILES_STRUCT,
CR_CTX_MM_STRUCT,
CR_CTX_NSPROXY,
CR_CTX_PID,
@@ -70,6 +71,7 @@ static inline void __user *cr_restore_ptr(__u64 ptr)
return (void __user *)(unsigned long)ptr;
}
+int cr_collect_all_files_struct(struct cr_context *ctx);
int cr_collect_all_file(struct cr_context *ctx);
int cr_collect_all_mm_struct(struct cr_context *ctx);
int cr_collect_all_nsproxy(struct cr_context *ctx);
@@ -78,6 +80,7 @@ int cr_collect_all_pid(struct cr_context *ctx);
int cr_collect_all_task_struct(struct cr_context *ctx);
int cr_collect_all_uts_ns(struct cr_context *ctx);
+int cr_dump_all_files_struct(struct cr_context *ctx);
int cr_dump_all_file(struct cr_context *ctx);
int cr_dump_all_mm_struct(struct cr_context *ctx);
int cr_dump_all_nsproxy(struct cr_context *ctx);
@@ -86,6 +89,7 @@ int cr_dump_all_pid(struct cr_context *ctx);
int cr_dump_all_task_struct(struct cr_context *ctx);
int cr_dump_all_uts_ns(struct cr_context *ctx);
+int cr_restore_files_struct(struct cr_context *ctx, loff_t pos);
int cr_restore_file(struct cr_context *ctx, loff_t pos);
int cr_restore_mm_struct(struct cr_context *ctx, loff_t pos);
int cr_restore_nsproxy(struct cr_context *ctx, loff_t pos);
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