vt: selection, push console lock down

We need to nest the console lock in sel_lock, so we have to push it down
a bit. Fortunately, the callers of set_selection_* just lock the console
lock around the function call. So moving it down is easy.

In the next patch, we switch the order.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Fixes: 07e6124a1a ("vt: selection, close sel_buffer race")
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20200228115406.5735-1-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Jiri Slaby 2020-02-28 12:54:05 +01:00 committed by Greg Kroah-Hartman
parent f8788d86ab
commit 4b70dd57a1
3 changed files with 12 additions and 5 deletions

View File

@ -51,9 +51,7 @@ static void __speakup_set_selection(struct work_struct *work)
goto unref;
}
console_lock();
set_selection_kernel(&sel, tty);
console_unlock();
unref:
tty_kref_put(tty);

View File

@ -181,7 +181,7 @@ int set_selection_user(const struct tiocl_selection __user *sel,
return set_selection_kernel(&v, tty);
}
int set_selection_kernel(struct tiocl_selection *v, struct tty_struct *tty)
static int __set_selection_kernel(struct tiocl_selection *v, struct tty_struct *tty)
{
struct vc_data *vc = vc_cons[fg_console].d;
int new_sel_start, new_sel_end, spc;
@ -343,6 +343,17 @@ unlock:
mutex_unlock(&sel_lock);
return ret;
}
int set_selection_kernel(struct tiocl_selection *v, struct tty_struct *tty)
{
int ret;
console_lock();
ret = __set_selection_kernel(v, tty);
console_unlock();
return ret;
}
EXPORT_SYMBOL_GPL(set_selection_kernel);
/* Insert the contents of the selection buffer into the

View File

@ -3046,10 +3046,8 @@ int tioclinux(struct tty_struct *tty, unsigned long arg)
switch (type)
{
case TIOCL_SETSEL:
console_lock();
ret = set_selection_user((struct tiocl_selection
__user *)(p+1), tty);
console_unlock();
break;
case TIOCL_PASTESEL:
ret = paste_selection(tty);