signalfd: lift sigmask copyin and size checks to callers of do_signalfd4()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Al Viro 2018-05-27 08:35:50 -04:00
parent 87a3002af9
commit 5ed0127fc3
1 changed files with 25 additions and 25 deletions

View File

@ -256,10 +256,8 @@ static const struct file_operations signalfd_fops = {
.llseek = noop_llseek,
};
static int do_signalfd4(int ufd, sigset_t __user *user_mask, size_t sizemask,
int flags)
static int do_signalfd4(int ufd, sigset_t *mask, int flags)
{
sigset_t sigmask;
struct signalfd_ctx *ctx;
/* Check the SFD_* constants for consistency. */
@ -269,18 +267,15 @@ static int do_signalfd4(int ufd, sigset_t __user *user_mask, size_t sizemask,
if (flags & ~(SFD_CLOEXEC | SFD_NONBLOCK))
return -EINVAL;
if (sizemask != sizeof(sigset_t) ||
copy_from_user(&sigmask, user_mask, sizeof(sigmask)))
return -EINVAL;
sigdelsetmask(&sigmask, sigmask(SIGKILL) | sigmask(SIGSTOP));
signotset(&sigmask);
sigdelsetmask(mask, sigmask(SIGKILL) | sigmask(SIGSTOP));
signotset(mask);
if (ufd == -1) {
ctx = kmalloc(sizeof(*ctx), GFP_KERNEL);
if (!ctx)
return -ENOMEM;
ctx->sigmask = sigmask;
ctx->sigmask = *mask;
/*
* When we call this, the initialization must be complete, since
@ -300,7 +295,7 @@ static int do_signalfd4(int ufd, sigset_t __user *user_mask, size_t sizemask,
return -EINVAL;
}
spin_lock_irq(&current->sighand->siglock);
ctx->sigmask = sigmask;
ctx->sigmask = *mask;
spin_unlock_irq(&current->sighand->siglock);
wake_up(&current->sighand->signalfd_wqh);
@ -313,46 +308,51 @@ static int do_signalfd4(int ufd, sigset_t __user *user_mask, size_t sizemask,
SYSCALL_DEFINE4(signalfd4, int, ufd, sigset_t __user *, user_mask,
size_t, sizemask, int, flags)
{
return do_signalfd4(ufd, user_mask, sizemask, flags);
sigset_t mask;
if (sizemask != sizeof(sigset_t) ||
copy_from_user(&mask, user_mask, sizeof(mask)))
return -EINVAL;
return do_signalfd4(ufd, &mask, flags);
}
SYSCALL_DEFINE3(signalfd, int, ufd, sigset_t __user *, user_mask,
size_t, sizemask)
{
return do_signalfd4(ufd, user_mask, sizemask, 0);
sigset_t mask;
if (sizemask != sizeof(sigset_t) ||
copy_from_user(&mask, user_mask, sizeof(mask)))
return -EINVAL;
return do_signalfd4(ufd, &mask, 0);
}
#ifdef CONFIG_COMPAT
static long do_compat_signalfd4(int ufd,
const compat_sigset_t __user *sigmask,
const compat_sigset_t __user *user_mask,
compat_size_t sigsetsize, int flags)
{
sigset_t tmp;
sigset_t __user *ksigmask;
sigset_t mask;
if (sigsetsize != sizeof(compat_sigset_t))
return -EINVAL;
if (get_compat_sigset(&tmp, sigmask))
if (get_compat_sigset(&mask, user_mask))
return -EFAULT;
ksigmask = compat_alloc_user_space(sizeof(sigset_t));
if (copy_to_user(ksigmask, &tmp, sizeof(sigset_t)))
return -EFAULT;
return do_signalfd4(ufd, ksigmask, sizeof(sigset_t), flags);
return do_signalfd4(ufd, &mask, flags);
}
COMPAT_SYSCALL_DEFINE4(signalfd4, int, ufd,
const compat_sigset_t __user *, sigmask,
const compat_sigset_t __user *, user_mask,
compat_size_t, sigsetsize,
int, flags)
{
return do_compat_signalfd4(ufd, sigmask, sigsetsize, flags);
return do_compat_signalfd4(ufd, user_mask, sigsetsize, flags);
}
COMPAT_SYSCALL_DEFINE3(signalfd, int, ufd,
const compat_sigset_t __user *,sigmask,
const compat_sigset_t __user *, user_mask,
compat_size_t, sigsetsize)
{
return do_compat_signalfd4(ufd, sigmask, sigsetsize, 0);
return do_compat_signalfd4(ufd, user_mask, sigsetsize, 0);
}
#endif