Merge branch 'work.sys_wait' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull wait syscall updates from Al Viro:
 "Consolidating sys_wait* and compat counterparts.

  Gets rid of set_fs()/double-copy mess, simplifies the whole thing
  (lifting the copyouts to the syscalls means less headache in the part
  that does actual work - fewer failure exits, to start with), gets rid
  of the overhead of field-by-field __put_user()"

* 'work.sys_wait' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  osf_wait4: switch to kernel_wait4()
  waitid(): switch copyout of siginfo to unsafe_put_user()
  wait_task_zombie: consolidate info logics
  kill wait_noreap_copyout()
  lift getrusage() from wait_noreap_copyout()
  waitid(2): leave copyout of siginfo to syscall itself
  kernel_wait4()/kernel_waitid(): delay copying status to userland
  wait4(2)/waitid(2): separate copying rusage to userland
  move compat wait4 and waitid next to native variants
This commit is contained in:
Linus Torvalds 2017-07-05 14:10:19 -07:00
commit 4be95131bf
6 changed files with 189 additions and 261 deletions

View file

@ -396,72 +396,6 @@ int put_compat_rusage(const struct rusage *r, struct compat_rusage __user *ru)
return 0;
}
COMPAT_SYSCALL_DEFINE4(wait4,
compat_pid_t, pid,
compat_uint_t __user *, stat_addr,
int, options,
struct compat_rusage __user *, ru)
{
if (!ru) {
return sys_wait4(pid, stat_addr, options, NULL);
} else {
struct rusage r;
int ret;
unsigned int status;
mm_segment_t old_fs = get_fs();
set_fs (KERNEL_DS);
ret = sys_wait4(pid,
(stat_addr ?
(unsigned int __user *) &status : NULL),
options, (struct rusage __user *) &r);
set_fs (old_fs);
if (ret > 0) {
if (put_compat_rusage(&r, ru))
return -EFAULT;
if (stat_addr && put_user(status, stat_addr))
return -EFAULT;
}
return ret;
}
}
COMPAT_SYSCALL_DEFINE5(waitid,
int, which, compat_pid_t, pid,
struct compat_siginfo __user *, uinfo, int, options,
struct compat_rusage __user *, uru)
{
siginfo_t info;
struct rusage ru;
long ret;
mm_segment_t old_fs = get_fs();
memset(&info, 0, sizeof(info));
set_fs(KERNEL_DS);
ret = sys_waitid(which, pid, (siginfo_t __user *)&info, options,
uru ? (struct rusage __user *)&ru : NULL);
set_fs(old_fs);
if ((ret < 0) || (info.si_signo == 0))
return ret;
if (uru) {
/* sys_waitid() overwrites everything in ru */
if (COMPAT_USE_64BIT_TIME)
ret = copy_to_user(uru, &ru, sizeof(ru));
else
ret = put_compat_rusage(&ru, uru);
if (ret)
return -EFAULT;
}
BUG_ON(info.si_code & __SI_MASK);
info.si_code |= __SI_CHLD;
return copy_siginfo_to_user32(uinfo, &info);
}
static int compat_get_user_cpu_mask(compat_ulong_t __user *user_mask_ptr,
unsigned len, struct cpumask *new_mask)
{