Re: [PATCH] read(tty, (char *)-1, 1) exempt from EFAULT ?

Steven Rostedt
2003-03-19T02:56:03Z

I had a cut and paste error in my last patch. This should be correct:

--- linux-2.4.20/drivers/char/n_tty.c_orig Tue Mar 18 20:19:33 2003
+++ linux-2.4.20/drivers/char/n_tty.c Tue Mar 18 21:06:57 2003
@@ -1030,7 +1030,10 @@
break;
cs = tty->link->ctrl_status;
tty->link->ctrl_status = 0;
- put_user(cs, b++);
+ if (put_user(cs, b++)) {
+ retval = -EFAULT;
+ break;
+ }
nr--;
break;
}
@@ -1069,7 +1072,10 @@

/* Deal with packet mode. */
if (tty->packet && b == buf) {
- put_user(TIOCPKT_DATA, b++);
+ if (put_user(TIOCPKT_DATA, b++)) {
+ retval = -EFAULT;
+ break;
+ }
nr--;
}

@@ -1096,12 +1102,17 @@
spin_unlock_irqrestore(&tty->read_lock,
flags);

if (!eol || (c != __DISABLED_CHAR)) {
- put_user(c, b++);
+ if (put_user(c, b++)) {
+ retval = -EFAULT;
+ break;
+ }
nr--;
}
if (eol)
break;
}
+ if (retval)
+ break;
} else {
int uncopied;
uncopied = copy_from_read_buf(tty, &b, &nr);
@@ -1136,7 +1147,7 @@

current->state = TASK_RUNNING;
size = b - buf;
- if (size) {
+ if (!retval && size) {
retval = size;
if (nr)
clear_bit(TTY_PUSH, &tty->flags);