redonkable
/
remarkable-linux
1
0
Fork 0
Code Releases Activity

signal: cleanup sys_rt_sigprocmask() 

sys_rt_sigprocmask() looks unnecessarily complicated, simplify it.
We can just read current->blocked lockless unconditionally before
anything else and then copy-to-user it if needed.  At worst we
copy 4 words on mips.

We could copy-to-user the old mask first and simplify the code even
more, but the patch tries to keep the current behaviour: we change
current->block even if copy_to_user(oset) fails.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Matt Fleming <matt.fleming@linux.intel.com>
Acked-by: Tejun Heo <tj@kernel.org>
wifi-calibration
Oleg Nesterov 2011-04-27 21:18:10 +02:00
parent e9bd3f0faa
commit bb7efee2ca
1 changed files with 17 additions and 23 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

40
kernel/signal.c
View File

@ -2364,40 +2364,34 @@ int sigprocmask(int how, sigset_t *set, sigset_t *oldset)
* @oset: previous value of signal mask if non-null
* @sigsetsize: size of sigset_t type
*/
SYSCALL_DEFINE4(rt_sigprocmask, int, how, sigset_t __user *, set,
SYSCALL_DEFINE4(rt_sigprocmask, int, how, sigset_t __user *, nset,
sigset_t __user *, oset, size_t, sigsetsize)
{
int error = -EINVAL;
sigset_t old_set, new_set;
int error;
/* XXX: Don't preclude handling different sized sigset_t's. */
if (sigsetsize != sizeof(sigset_t))
goto out;
return -EINVAL;
if (set) {
error = -EFAULT;
if (copy_from_user(&new_set, set, sizeof(*set)))
goto out;
old_set = current->blocked;
if (nset) {
if (copy_from_user(&new_set, nset, sizeof(sigset_t)))
return -EFAULT;
sigdelsetmask(&new_set, sigmask(SIGKILL)|sigmask(SIGSTOP));
error = sigprocmask(how, &new_set, &old_set);
error = sigprocmask(how, &new_set, NULL);
if (error)
goto out;
if (oset)
goto set_old;
} else if (oset) {
spin_lock_irq(&current->sighand->siglock);
old_set = current->blocked;
spin_unlock_irq(&current->sighand->siglock);
set_old:
error = -EFAULT;
if (copy_to_user(oset, &old_set, sizeof(*oset)))
goto out;
return error;
}
error = 0;
out:
return error;
if (oset) {
if (copy_to_user(oset, &old_set, sizeof(sigset_t)))
return -EFAULT;
}
return 0;
}
long do_sigpending(void __user *set, unsigned long sigsetsize)