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Diffstat (limited to 'drivers/char')
-rw-r--r--drivers/char/random.c19
-rw-r--r--drivers/char/tty_io.c7
-rw-r--r--drivers/char/tty_ioctl.c6
3 files changed, 18 insertions, 14 deletions
diff --git a/drivers/char/random.c b/drivers/char/random.c
index 1838aa3d24f..7ce1ac4baa6 100644
--- a/drivers/char/random.c
+++ b/drivers/char/random.c
@@ -407,7 +407,7 @@ struct entropy_store {
/* read-write data: */
spinlock_t lock;
unsigned add_ptr;
- int entropy_count;
+ int entropy_count; /* Must at no time exceed ->POOLBITS! */
int input_rotate;
};
@@ -520,6 +520,7 @@ static void mix_pool_bytes(struct entropy_store *r, const void *in, int bytes)
static void credit_entropy_bits(struct entropy_store *r, int nbits)
{
unsigned long flags;
+ int entropy_count;
if (!nbits)
return;
@@ -527,20 +528,20 @@ static void credit_entropy_bits(struct entropy_store *r, int nbits)
spin_lock_irqsave(&r->lock, flags);
DEBUG_ENT("added %d entropy credits to %s\n", nbits, r->name);
- r->entropy_count += nbits;
- if (r->entropy_count < 0) {
+ entropy_count = r->entropy_count;
+ entropy_count += nbits;
+ if (entropy_count < 0) {
DEBUG_ENT("negative entropy/overflow\n");
- r->entropy_count = 0;
- } else if (r->entropy_count > r->poolinfo->POOLBITS)
- r->entropy_count = r->poolinfo->POOLBITS;
+ entropy_count = 0;
+ } else if (entropy_count > r->poolinfo->POOLBITS)
+ entropy_count = r->poolinfo->POOLBITS;
+ r->entropy_count = entropy_count;
/* should we wake readers? */
- if (r == &input_pool &&
- r->entropy_count >= random_read_wakeup_thresh) {
+ if (r == &input_pool && entropy_count >= random_read_wakeup_thresh) {
wake_up_interruptible(&random_read_wait);
kill_fasync(&fasync, SIGIO, POLL_IN);
}
-
spin_unlock_irqrestore(&r->lock, flags);
}
diff --git a/drivers/char/tty_io.c b/drivers/char/tty_io.c
index a27160ba21d..daeb8f76697 100644
--- a/drivers/char/tty_io.c
+++ b/drivers/char/tty_io.c
@@ -2498,7 +2498,7 @@ static int tiocgwinsz(struct tty_struct *tty, struct winsize __user *arg)
/**
* tty_do_resize - resize event
* @tty: tty being resized
- * @real_tty: real tty (if using a pty/tty pair)
+ * @real_tty: real tty (not the same as tty if using a pty/tty pair)
* @rows: rows (character)
* @cols: cols (character)
*
@@ -2512,7 +2512,8 @@ int tty_do_resize(struct tty_struct *tty, struct tty_struct *real_tty,
struct pid *pgrp, *rpgrp;
unsigned long flags;
- mutex_lock(&tty->termios_mutex);
+ /* For a PTY we need to lock the tty side */
+ mutex_lock(&real_tty->termios_mutex);
if (!memcmp(ws, &tty->winsize, sizeof(*ws)))
goto done;
/* Get the PID values and reference them so we can
@@ -2533,7 +2534,7 @@ int tty_do_resize(struct tty_struct *tty, struct tty_struct *real_tty,
tty->winsize = *ws;
real_tty->winsize = *ws;
done:
- mutex_unlock(&tty->termios_mutex);
+ mutex_unlock(&real_tty->termios_mutex);
return 0;
}
diff --git a/drivers/char/tty_ioctl.c b/drivers/char/tty_ioctl.c
index ea9fc5d03b9..bf34e459742 100644
--- a/drivers/char/tty_ioctl.c
+++ b/drivers/char/tty_ioctl.c
@@ -937,12 +937,14 @@ int tty_mode_ioctl(struct tty_struct *tty, struct file *file,
return 0;
#endif
case TIOCGSOFTCAR:
- return put_user(C_CLOCAL(tty) ? 1 : 0,
+ /* FIXME: for correctness we may need to take the termios
+ lock here - review */
+ return put_user(C_CLOCAL(real_tty) ? 1 : 0,
(int __user *)arg);
case TIOCSSOFTCAR:
if (get_user(arg, (unsigned int __user *) arg))
return -EFAULT;
- return tty_change_softcar(tty, arg);
+ return tty_change_softcar(real_tty, arg);
default:
return -ENOIOCTLCMD;
}