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files.c
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files.c
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#include <unistd.h>
#include <fcntl.h>
#include <errno.h>
#include <linux/limits.h>
#include <linux/major.h>
#include <sys/types.h>
#include <sys/prctl.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <sys/socket.h>
#include <sys/un.h>
#include <stdlib.h>
#include "types.h"
#include "files.h"
#include "file-ids.h"
#include "files-reg.h"
#include "file-lock.h"
#include "image.h"
#include "common/list.h"
#include "rst-malloc.h"
#include "util-caps.h"
#include "common/lock.h"
#include "sockets.h"
#include "pstree.h"
#include "tty.h"
#include "pipes.h"
#include "fifo.h"
#include "eventfd.h"
#include "eventpoll.h"
#include "fsnotify.h"
#include "sk-packet.h"
#include "mount.h"
#include "signalfd.h"
#include "memfd.h"
#include "namespaces.h"
#include "tun.h"
#include "timerfd.h"
#include "imgset.h"
#include "fs-magic.h"
#include "fdinfo.h"
#include "cr_options.h"
#include "autofs.h"
#include "parasite.h"
#include "parasite-syscall.h"
#include "string.h"
#include "kerndat.h"
#include "fdstore.h"
#include "bpfmap.h"
#include "protobuf.h"
#include "util.h"
#include "images/fs.pb-c.h"
#include "images/ext-file.pb-c.h"
#include "plugin.h"
#define FDESC_HASH_SIZE 64
static struct hlist_head file_desc_hash[FDESC_HASH_SIZE];
/* file_desc's, which fle is not owned by a process, that is able to open them */
static LIST_HEAD(fake_master_head);
static u32 max_file_desc_id = 0;
static void init_fdesc_hash(void)
{
int i;
for (i = 0; i < FDESC_HASH_SIZE; i++)
INIT_HLIST_HEAD(&file_desc_hash[i]);
}
void file_desc_init(struct file_desc *d, u32 id, struct file_desc_ops *ops)
{
INIT_LIST_HEAD(&d->fd_info_head);
INIT_LIST_HEAD(&d->fake_master_list);
INIT_HLIST_NODE(&d->hash);
d->id = id;
d->ops = ops;
}
int file_desc_add(struct file_desc *d, u32 id, struct file_desc_ops *ops)
{
file_desc_init(d, id, ops);
hlist_add_head(&d->hash, &file_desc_hash[id % FDESC_HASH_SIZE]);
if (id > max_file_desc_id)
max_file_desc_id = id;
return 0; /* this is to make tail-calls in collect_one_foo look nice */
}
struct file_desc *find_file_desc_raw(int type, u32 id)
{
struct file_desc *d;
struct hlist_head *chain;
chain = &file_desc_hash[id % FDESC_HASH_SIZE];
hlist_for_each_entry(d, chain, hash)
if ((d->id == id) && (d->ops->type == type || type == FD_TYPES__UND))
/*
* Warning -- old CRIU might generate matching IDs
* for different file types! So any code that uses
* FD_TYPES__UND for fdesc search MUST make sure it's
* dealing with the merged files images where all
* descs are forced to have different IDs.
*/
return d;
return NULL;
}
static inline struct file_desc *find_file_desc(FdinfoEntry *fe)
{
return find_file_desc_raw(fe->type, fe->id);
}
u32 find_unused_file_desc_id(void)
{
return max_file_desc_id + 1;
}
struct fdinfo_list_entry *find_used_fd(struct pstree_item *task, int fd)
{
struct list_head *head;
struct fdinfo_list_entry *fle;
head = &rsti(task)->fds;
list_for_each_entry_reverse(fle, head, ps_list) {
if (fle->fe->fd == fd)
return fle;
/* List is ordered, so let's stop */
if (fle->fe->fd < fd)
break;
}
return NULL;
}
static void collect_task_fd(struct fdinfo_list_entry *new_fle, struct rst_info *ri)
{
struct fdinfo_list_entry *fle;
/*
* fles in fds list are ordered by fd. Fds are restored from img files
* in ascending order, so it is faster to insert them from the end of
* the list.
*/
list_for_each_entry_reverse(fle, &ri->fds, ps_list) {
if (fle->fe->fd < new_fle->fe->fd)
break;
}
list_add(&new_fle->ps_list, &fle->ps_list);
}
unsigned int find_unused_fd(struct pstree_item *task, int hint_fd)
{
struct list_head *head;
struct fdinfo_list_entry *fle;
int fd = 0, prev_fd;
if ((hint_fd >= 0) && (!find_used_fd(task, hint_fd))) {
fd = hint_fd;
goto out;
}
prev_fd = service_fd_min_fd(task) - 1;
head = &rsti(task)->fds;
list_for_each_entry_reverse(fle, head, ps_list) {
fd = fle->fe->fd;
if (prev_fd > fd) {
fd++;
goto out;
}
prev_fd = fd - 1;
}
BUG();
out:
return fd;
}
int find_unused_fd_pid(pid_t pid)
{
struct pstree_item *task;
task = pstree_item_by_virt(pid);
if (!task) {
pr_err("Invalid pid:%d\n", pid);
return -1;
}
return find_unused_fd(task, -1);
}
int set_fds_event(pid_t virt)
{
struct pstree_item *item;
bool is_set;
item = pstree_item_by_virt(virt);
BUG_ON(!item);
is_set = !!test_and_set_bit_le(FDS_EVENT_BIT, &item->task_st_le_bits);
if (!is_set)
futex_wake(&item->task_st);
return 0;
}
void clear_fds_event(void)
{
clear_bit_le(FDS_EVENT_BIT, ¤t->task_st_le_bits);
}
void wait_fds_event(void)
{
futex_t *f = ¤t->task_st;
int value;
value = htole32(FDS_EVENT);
futex_wait_if_cond(f, value, &);
clear_fds_event();
}
struct fdinfo_list_entry *try_file_master(struct file_desc *d)
{
if (list_empty(&d->fd_info_head))
return NULL;
return list_first_entry(&d->fd_info_head, struct fdinfo_list_entry, desc_list);
}
struct fdinfo_list_entry *file_master(struct file_desc *d)
{
struct fdinfo_list_entry *fle;
fle = try_file_master(d);
if (!fle) {
pr_err("Empty list on file desc id %#x(%d)\n", d->id, d->ops ? d->ops->type : -1);
BUG();
}
return fle;
}
void show_saved_files(void)
{
int i;
struct file_desc *fd;
pr_info("File descs:\n");
for (i = 0; i < FDESC_HASH_SIZE; i++)
hlist_for_each_entry(fd, &file_desc_hash[i], hash) {
struct fdinfo_list_entry *le;
pr_info(" `- type %d ID %#x\n", fd->ops->type, fd->id);
list_for_each_entry(le, &fd->fd_info_head, desc_list)
pr_info(" `- FD %d pid %d\n", le->fe->fd, le->pid);
}
}
/*
* Workaround for the OverlayFS bug present before Kernel 4.2
*
* This is here only to support the Linux Kernel between versions
* 3.18 and 4.2. After that, this workaround is not needed anymore,
* but it will work properly on both a kernel with and without the bug.
*
* When a process has a file open in an OverlayFS directory,
* the information in /proc/<pid>/fd/<fd> and /proc/<pid>/fdinfo/<fd>
* is wrong. We can't even rely on stat()-ing /proc/<pid>/fd/<fd> since
* this will show us the wrong filesystem type.
*
* So we grab that information from the mountinfo table instead. This is done
* every time fill_fdlink is called. See lookup_overlayfs for more details.
*
*/
static int fixup_overlayfs(struct fd_parms *p, struct fd_link *link)
{
struct mount_info *m;
if (!link)
return 0;
m = lookup_overlayfs(link->name, p->stat.st_dev, p->stat.st_ino, p->mnt_id);
if (IS_ERR(m))
return -1;
if (!m)
return 0;
p->mnt_id = m->mnt_id;
/*
* If the bug is present, the file path from /proc/<pid>/fd
* does not include the mountpoint, so we prepend it ourselves.
*/
if (strcmp("./", m->ns_mountpoint) != 0) {
char buf[PATH_MAX];
int n;
__strlcpy(buf, link->name, PATH_MAX);
n = snprintf(link->name, PATH_MAX, "%s/%s", m->ns_mountpoint, buf + 2);
if (n >= PATH_MAX) {
pr_err("Not enough space to replace %s\n", buf);
return -1;
}
}
return 0;
}
/*
* The gen_id thing is used to optimize the comparison of shared files.
* If two files have different gen_ids, then they are different for sure.
* If it matches, we don't know it and have to call sys_kcmp().
*
* The kcmp-ids.c engine does this trick, see comments in it for more info.
*/
uint32_t make_gen_id(uint32_t st_dev, uint32_t st_ino, uint64_t pos)
{
uint32_t pos_hi = pos >> 32;
uint32_t pos_low = pos & 0xffffffff;
return st_dev ^ st_ino ^ pos_hi ^ pos_low;
}
int do_dump_gen_file(struct fd_parms *p, int lfd, const struct fdtype_ops *ops, FdinfoEntry *e)
{
int ret = -1;
e->type = ops->type;
e->id = make_gen_id((uint32_t)p->stat.st_dev, (uint32_t)p->stat.st_ino, (uint64_t)p->pos);
e->fd = p->fd;
e->flags = p->fd_flags;
ret = fd_id_generate(p->pid, e, p);
if (ret == 1) /* new ID generated */
ret = ops->dump(lfd, e->id, p);
else
/* Remove locks generated by the fd before going to the next */
discard_dup_locks_tail(p->pid, e->fd);
return ret;
}
int fill_fdlink(int lfd, const struct fd_parms *p, struct fd_link *link)
{
int len;
link->name[0] = '.';
len = read_fd_link(lfd, &link->name[1], sizeof(link->name) - 1);
if (len < 0) {
pr_err("Can't read link for pid %d fd %d\n", p->pid, p->fd);
return -1;
}
link->len = len + 1;
if (opts.overlayfs)
if (fixup_overlayfs((struct fd_parms *)p, link) < 0)
return -1;
return 0;
}
static int fill_fd_params(struct pid *owner_pid, int fd, int lfd, struct fd_opts *opts, struct fd_parms *p)
{
int ret;
struct statfs fsbuf;
struct fdinfo_common fdinfo = { .mnt_id = -1, .owner = owner_pid->ns[0].virt };
if (fstat(lfd, &p->stat) < 0) {
pr_perror("Can't stat fd %d", lfd);
return -1;
}
if (fstatfs(lfd, &fsbuf) < 0) {
pr_perror("Can't statfs fd %d", lfd);
return -1;
}
if (parse_fdinfo_pid(owner_pid->real, fd, FD_TYPES__UND, &fdinfo))
return -1;
p->fs_type = fsbuf.f_type;
p->fd = fd;
p->pos = fdinfo.pos;
/*
* The kernel artificially adds the O_CLOEXEC flag on the file pointer
* flags by looking at the flags on the file descriptor (see kernel
* code fs/proc/fd.c). FD_CLOEXEC is a file descriptor property, which
* is saved in fd_flags.
*/
p->flags = fdinfo.flags & ~O_CLOEXEC;
p->mnt_id = fdinfo.mnt_id;
p->pid = owner_pid->real;
p->fd_flags = opts->flags;
fown_entry__init(&p->fown);
pr_info("%d fdinfo %d: pos: %#16" PRIx64 " flags: %16o/%#x\n", owner_pid->real, fd, p->pos, p->flags,
(int)p->fd_flags);
if (p->flags & O_PATH)
ret = 0;
else
ret = fcntl(lfd, F_GETSIG, 0);
if (ret < 0) {
pr_perror("Can't get owner signum on %d", lfd);
return -1;
}
p->fown.signum = ret;
if (opts->fown.pid == 0)
return 0;
p->fown.pid = opts->fown.pid;
p->fown.pid_type = opts->fown.pid_type;
p->fown.uid = opts->fown.uid;
p->fown.euid = opts->fown.euid;
return 0;
}
static const struct fdtype_ops *get_misc_dev_ops(int minor)
{
switch (minor) {
case TUN_MINOR:
return &tunfile_dump_ops;
case AUTOFS_MINOR:
return ®file_dump_ops;
};
return NULL;
}
static const struct fdtype_ops *get_mem_dev_ops(struct fd_parms *p, int minor)
{
const struct fdtype_ops *ops = NULL;
/*
* If /dev/kmsg is opened in write-only mode the file position
* should not be set up upon restore, kernel doesn't allow that.
*/
if (minor == 11 && (p->flags & O_ACCMODE) == O_WRONLY && p->pos == 0)
p->pos = -1ULL;
ops = ®file_dump_ops;
return ops;
}
static int dump_chrdev(struct fd_parms *p, int lfd, FdinfoEntry *e)
{
struct fd_link *link_old = p->link;
int maj = major(p->stat.st_rdev);
const struct fdtype_ops *ops;
struct fd_link link;
int err;
switch (maj) {
case MEM_MAJOR:
ops = get_mem_dev_ops(p, minor(p->stat.st_rdev));
break;
case MISC_MAJOR:
ops = get_misc_dev_ops(minor(p->stat.st_rdev));
if (ops)
break;
/* fallthrough */
default: {
char more[32];
if (is_tty(p->stat.st_rdev, p->stat.st_dev)) {
if (fill_fdlink(lfd, p, &link))
return -1;
p->link = &link;
ops = &tty_dump_ops;
break;
}
sprintf(more, "%d:%d", maj, minor(p->stat.st_rdev));
err = dump_unsupp_fd(p, lfd, "chr", more, e);
p->link = link_old;
return err;
}
}
err = do_dump_gen_file(p, lfd, ops, e);
p->link = link_old;
return err;
}
static int dump_one_file(struct pid *pid, int fd, int lfd, struct fd_opts *opts, struct parasite_ctl *ctl,
FdinfoEntry *e, struct parasite_drain_fd *dfds)
{
struct fd_parms p = FD_PARMS_INIT;
const struct fdtype_ops *ops;
struct fd_link link;
if (fill_fd_params(pid, fd, lfd, opts, &p) < 0) {
pr_err("Can't get stat on %d\n", fd);
return -1;
}
if (note_file_lock(pid, fd, lfd, &p))
return -1;
/* Lease can be set only on regular file */
if (S_ISREG(p.stat.st_mode)) {
int ret = correct_file_leases_type(pid, fd, lfd);
if (ret < 0)
return ret;
}
p.fd_ctl = ctl; /* Some dump_opts require this to talk to parasite */
p.dfds = dfds; /* epoll needs to verify if target fd exist */
if (S_ISSOCK(p.stat.st_mode))
return dump_socket(&p, lfd, e);
if (S_ISCHR(p.stat.st_mode))
return dump_chrdev(&p, lfd, e);
if (p.fs_type == ANON_INODE_FS_MAGIC) {
char link[32];
if (read_fd_link(lfd, link, sizeof(link)) < 0)
return -1;
if (is_eventfd_link(link))
ops = &eventfd_dump_ops;
else if (is_eventpoll_link(link))
ops = &eventpoll_dump_ops;
else if (is_inotify_link(link))
ops = &inotify_dump_ops;
else if (is_fanotify_link(link))
ops = &fanotify_dump_ops;
else if (is_signalfd_link(link))
ops = &signalfd_dump_ops;
else if (is_timerfd_link(link))
ops = &timerfd_dump_ops;
#ifdef CONFIG_HAS_LIBBPF
else if (is_bpfmap_link(link))
ops = &bpfmap_dump_ops;
#endif
else
return dump_unsupp_fd(&p, lfd, "anon", link, e);
return do_dump_gen_file(&p, lfd, ops, e);
}
if (S_ISREG(p.stat.st_mode) || S_ISDIR(p.stat.st_mode) || S_ISLNK(p.stat.st_mode)) {
if (fill_fdlink(lfd, &p, &link))
return -1;
p.link = &link;
/* TODO: Dump for hugetlb fd when memfd hugetlb is not supported */
if (is_memfd(p.stat.st_dev) || (kdat.has_memfd_hugetlb && is_hugetlb_dev(p.stat.st_dev, NULL)))
ops = &memfd_dump_ops;
else if (link.name[1] == '/')
ops = ®file_dump_ops;
else if (check_ns_proc(&link))
ops = &nsfile_dump_ops;
else
return dump_unsupp_fd(&p, lfd, "reg", link.name + 1, e);
return do_dump_gen_file(&p, lfd, ops, e);
}
if (S_ISFIFO(p.stat.st_mode)) {
if (p.fs_type == PIPEFS_MAGIC)
ops = &pipe_dump_ops;
else
ops = &fifo_dump_ops;
return do_dump_gen_file(&p, lfd, ops, e);
}
/*
* For debug purpose -- at least show the link
* file pointing to when reporting unsupported file.
* On error simply empty string here.
*/
if (fill_fdlink(lfd, &p, &link))
memzero(&link, sizeof(link));
return dump_unsupp_fd(&p, lfd, "unknown", link.name + 1, e);
}
int dump_my_file(int lfd, u32 *id, int *type)
{
struct pid me = {};
struct fd_opts fdo = {};
FdinfoEntry e = FDINFO_ENTRY__INIT;
me.real = getpid();
me.ns[0].virt = -1; /* FIXME */
if (dump_one_file(&me, lfd, lfd, &fdo, NULL, &e, NULL))
return -1;
*id = e.id;
*type = e.type;
return 0;
}
int dump_task_files_seized(struct parasite_ctl *ctl, struct pstree_item *item, struct parasite_drain_fd *dfds)
{
int *lfds = NULL;
struct cr_img *img = NULL;
struct fd_opts *opts = NULL;
int i, ret = -1;
int off, nr_fds = min((int)PARASITE_MAX_FDS, dfds->nr_fds);
pr_info("\n");
pr_info("Dumping opened files (pid: %d)\n", item->pid->real);
pr_info("----------------------------------------\n");
lfds = xmalloc(nr_fds * sizeof(int));
if (!lfds)
goto err;
opts = xmalloc(nr_fds * sizeof(struct fd_opts));
if (!opts)
goto err;
img = open_image(CR_FD_FDINFO, O_DUMP, item->ids->files_id);
if (!img)
goto err;
ret = 0; /* Don't fail if nr_fds == 0 */
for (off = 0; ret == 0 && off < dfds->nr_fds; off += nr_fds) {
if (nr_fds + off > dfds->nr_fds)
nr_fds = dfds->nr_fds - off;
ret = parasite_drain_fds_seized(ctl, dfds, nr_fds, off, lfds, opts);
if (ret)
goto err;
for (i = 0; i < nr_fds; i++) {
FdinfoEntry e = FDINFO_ENTRY__INIT;
ret = dump_one_file(item->pid, dfds->fds[i + off], lfds[i], opts + i, ctl, &e, dfds);
if (ret)
break;
ret = pb_write_one(img, &e, PB_FDINFO);
if (ret)
break;
}
for (i = 0; i < nr_fds; i++)
close(lfds[i]);
}
pr_info("----------------------------------------\n");
err:
if (img)
close_image(img);
xfree(opts);
xfree(lfds);
return ret;
}
static int predump_one_fd(int pid, int fd)
{
const struct fdtype_ops *ops;
char link[PATH_MAX], t[32];
int ret = 0;
snprintf(t, sizeof(t), "/proc/%d/fd/%d", pid, fd);
ret = readlink(t, link, sizeof(link));
if (ret < 0) {
pr_perror("Can't read link of fd %d", fd);
return -1;
} else if ((size_t)ret == sizeof(link)) {
pr_err("Buffer for read link of fd %d is too small\n", fd);
return -1;
}
link[ret] = 0;
ret = 0;
if (is_inotify_link(link))
ops = &inotify_dump_ops;
else if (is_fanotify_link(link))
ops = &fanotify_dump_ops;
else
goto out;
pr_debug("Pre-dumping %d's %d fd\n", pid, fd);
ret = ops->pre_dump(pid, fd);
out:
return ret;
}
int predump_task_files(int pid)
{
struct dirent *de;
DIR *fd_dir;
int ret = -1;
pr_info("Pre-dump fds for %d)\n", pid);
fd_dir = opendir_proc(pid, "fd");
if (!fd_dir)
return -1;
while ((de = readdir(fd_dir))) {
if (dir_dots(de))
continue;
if (predump_one_fd(pid, atoi(de->d_name)))
goto out;
}
ret = 0;
out:
closedir(fd_dir);
return ret;
}
int restore_fown(int fd, FownEntry *fown)
{
struct f_owner_ex owner;
uid_t uids[3];
if (fown->signum) {
if (fcntl(fd, F_SETSIG, fown->signum)) {
pr_perror("Can't set signal");
return -1;
}
}
/* May be untouched */
if (!fown->pid)
return 0;
if (getresuid(&uids[0], &uids[1], &uids[2])) {
pr_perror("Can't get current UIDs");
return -1;
}
if (setresuid(fown->uid, fown->euid, uids[2])) {
pr_perror("Can't set UIDs");
return -1;
}
owner.type = fown->pid_type;
owner.pid = fown->pid;
if (fcntl(fd, F_SETOWN_EX, &owner)) {
pr_perror("Can't setup %d file owner pid", fd);
return -1;
}
if (setresuid(uids[0], uids[1], uids[2])) {
pr_perror("Can't revert UIDs back");
return -1;
}
if (prctl(PR_SET_DUMPABLE, 1, 0))
pr_perror("Unable to set PR_SET_DUMPABLE");
return 0;
}
int rst_file_params(int fd, FownEntry *fown, int flags)
{
if (set_fd_flags(fd, flags) < 0)
return -1;
if (restore_fown(fd, fown) < 0)
return -1;
return 0;
}
static struct fdinfo_list_entry *alloc_fle(int pid, FdinfoEntry *fe)
{
struct fdinfo_list_entry *fle;
fle = shmalloc(sizeof(*fle));
if (!fle)
return NULL;
fle->pid = pid;
fle->fe = fe;
fle->received = 0;
fle->fake = 0;
fle->stage = FLE_INITIALIZED;
fle->task = pstree_item_by_virt(pid);
if (!fle->task) {
pr_err("Can't find task with pid %d\n", pid);
shfree_last(fle);
return NULL;
}
return fle;
}
static void __collect_desc_fle(struct fdinfo_list_entry *new_le, struct file_desc *fdesc)
{
struct fdinfo_list_entry *le;
list_for_each_entry_reverse(le, &fdesc->fd_info_head, desc_list)
if (pid_rst_prio_eq(le->pid, new_le->pid))
break;
list_add(&new_le->desc_list, &le->desc_list);
}
static void collect_desc_fle(struct fdinfo_list_entry *new_le, struct file_desc *fdesc, bool force_master)
{
new_le->desc = fdesc;
if (!force_master)
__collect_desc_fle(new_le, fdesc);
else {
/* Link as first entry */
list_add(&new_le->desc_list, &fdesc->fd_info_head);
}
}
struct fdinfo_list_entry *collect_fd_to(int pid, FdinfoEntry *e, struct rst_info *rst_info, struct file_desc *fdesc,
bool fake, bool force_master)
{
struct fdinfo_list_entry *new_le;
new_le = alloc_fle(pid, e);
if (new_le) {
new_le->fake = (!!fake);
collect_desc_fle(new_le, fdesc, force_master);
collect_task_fd(new_le, rst_info);
}
return new_le;
}
int collect_fd(int pid, FdinfoEntry *e, struct rst_info *rst_info, bool fake)
{
struct file_desc *fdesc;
pr_info("Collect fdinfo pid=%d fd=%d id=%#x\n", pid, e->fd, e->id);
fdesc = find_file_desc(e);
if (fdesc == NULL) {
pr_err("No file for fd %d id %#x\n", e->fd, e->id);
return -1;
}
if (!collect_fd_to(pid, e, rst_info, fdesc, fake, false))
return -1;
return 0;
}
FdinfoEntry *dup_fdinfo(FdinfoEntry *old, int fd, unsigned flags)
{
FdinfoEntry *e;
e = shmalloc(sizeof(*e));
if (!e)
return NULL;
fdinfo_entry__init(e);
e->id = old->id;
e->type = old->type;
e->fd = fd;
e->flags = flags;
return e;
}
int dup_fle(struct pstree_item *task, struct fdinfo_list_entry *ple, int fd, unsigned flags)
{
FdinfoEntry *e;
e = dup_fdinfo(ple->fe, fd, flags);
if (!e)
return -1;
return collect_fd(vpid(task), e, rsti(task), false);
}
int prepare_fd_pid(struct pstree_item *item)
{
int ret = 0;
struct cr_img *img;
pid_t pid = vpid(item);
struct rst_info *rst_info = rsti(item);
INIT_LIST_HEAD(&rst_info->fds);
if (item->ids == NULL) /* zombie */
return 0;
if (rsti(item)->fdt && rsti(item)->fdt->pid != vpid(item))
return 0;
img = open_image(CR_FD_FDINFO, O_RSTR, item->ids->files_id);
if (!img)
return -1;
while (1) {
FdinfoEntry *e;
ret = pb_read_one_eof(img, &e, PB_FDINFO);
if (ret <= 0)
break;
if (e->fd >= kdat.sysctl_nr_open) {
ret = -1;
pr_err("Too big FD number to restore %d\n", e->fd);
break;
}
ret = collect_fd(pid, e, rst_info, false);
if (ret < 0) {
fdinfo_entry__free_unpacked(e, NULL);
break;
}
}
close_image(img);
return ret;
}
#define SETFL_MASK (O_APPEND | O_ASYNC | O_NONBLOCK | O_NDELAY | O_DIRECT | O_NOATIME)
int set_fd_flags(int fd, int flags)
{
int ret;
ret = fcntl(fd, F_GETFL, 0);
if (ret < 0)
goto err;
flags = (SETFL_MASK & flags) | (ret & ~SETFL_MASK);
ret = fcntl(fd, F_SETFL, flags);
if (ret < 0)
goto err;
/* Let's check, that now actual flags contains those we need */
ret = fcntl(fd, F_GETFL, 0);
if (ret < 0)
goto err;
if (ret != flags) {
pr_err("fcntl call on fd %d (flags %#o) succeeded, "
"but some flags were dropped: %#o\n",
fd, flags, ret);
return -1;
}
return 0;
err:
pr_perror("fcntl call on fd %d (flags %x) failed", fd, flags);
return -1;
}
struct fd_open_state {
char *name;
int (*cb)(int, struct fdinfo_list_entry *);
};
static int receive_fd(struct fdinfo_list_entry *fle);
static void transport_name_gen(struct sockaddr_un *addr, int *len, int pid)
{
addr->sun_family = AF_UNIX;
snprintf(addr->sun_path, UNIX_PATH_MAX, "x/crtools-fd-%d-%" PRIx64, pid, criu_run_id);
*len = SUN_LEN(addr);
*addr->sun_path = '\0';
}
static bool task_fle(struct pstree_item *task, struct fdinfo_list_entry *fle)
{
struct fdinfo_list_entry *tmp;
list_for_each_entry(tmp, &rsti(task)->fds, ps_list)
if (fle == tmp)
return true;
return false;
}
static int plant_fd(struct fdinfo_list_entry *fle, int fd)
{
BUG_ON(fle->received);
fle->received = 1;
return reopen_fd_as(fle->fe->fd, fd);
}
static int recv_fd_from_peer(struct fdinfo_list_entry *fle)
{
struct fdinfo_list_entry *tmp;
int fd, ret, tsock;
if (fle->received)