TTY/Serial fixes for 5.10-rc2

Here are some small TTY and Serial driver fixes for reported issues for
 5.10-rc2.  They include:
 	- vt ioctl bugfix for reported problems
 	- fsl_lpuart serial driver fix
 	- 21285 serial driver bugfix
 
 All have been in linux-next with no reported issues.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
 -----BEGIN PGP SIGNATURE-----
 
 iG0EABECAC0WIQT0tgzFv3jCIUoxPcsxR9QN2y37KQUCX56xhw8cZ3JlZ0Brcm9h
 aC5jb20ACgkQMUfUDdst+yksqQCggSGz0Ez7CeOxRCQpARQ8ew0BaNcAnRqL2GtO
 ZTSQQn2vZzhFlTpnr03i
 =aaTK
 -----END PGP SIGNATURE-----

Merge tag 'tty-5.10-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty/serial fixes from Greg KH:
 "Here are some small TTY and Serial driver fixes for reported issues
  for 5.10-rc2. They include:

   - vt ioctl bugfix for reported problems

   - fsl_lpuart serial driver fix

   - 21285 serial driver bugfix

  All have been in linux-next with no reported issues"

* tag 'tty-5.10-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
  vt_ioctl: fix GIO_UNIMAP regression
  vt: keyboard, extend func_buf_lock to readers
  vt: keyboard, simplify vt_kdgkbsent
  tty: serial: fsl_lpuart: LS1021A has a FIFO size of 16 words, like LS1028A
  tty: serial: 21285: fix lockup on open

drivers/tty/serial/21285.c

@@ -50,25 +50,25 @@ static const char serial21285_name[] = "Footbridge UART";
 
 static bool is_enabled(struct uart_port *port, int bit)
 {
-	unsigned long private_data = (unsigned long)port->private_data;
+	unsigned long *private_data = (unsigned long *)&port->private_data;
 
-	if (test_bit(bit, &private_data))
+	if (test_bit(bit, private_data))
 		return true;
 	return false;
 }
 
 static void enable(struct uart_port *port, int bit)
 {
-	unsigned long private_data = (unsigned long)port->private_data;
+	unsigned long *private_data = (unsigned long *)&port->private_data;
 
-	set_bit(bit, &private_data);
+	set_bit(bit, private_data);
 }
 
 static void disable(struct uart_port *port, int bit)
 {
-	unsigned long private_data = (unsigned long)port->private_data;
+	unsigned long *private_data = (unsigned long *)&port->private_data;
 
-	clear_bit(bit, &private_data);
+	clear_bit(bit, private_data);
 }
 
 #define is_tx_enabled(port)	is_enabled(port, tx_enabled_bit)

drivers/tty/serial/fsl_lpuart.c

@@ -314,9 +314,10 @@ MODULE_DEVICE_TABLE(of, lpuart_dt_ids);
 /* Forward declare this for the dma callbacks*/
 static void lpuart_dma_tx_complete(void *arg);
 
-static inline bool is_ls1028a_lpuart(struct lpuart_port *sport)
+static inline bool is_layerscape_lpuart(struct lpuart_port *sport)
 {
-	return sport->devtype == LS1028A_LPUART;
+	return (sport->devtype == LS1021A_LPUART ||
+		sport->devtype == LS1028A_LPUART);
 }
 
 static inline bool is_imx8qxp_lpuart(struct lpuart_port *sport)
@@ -1701,11 +1702,11 @@ static int lpuart32_startup(struct uart_port *port)
 					    UARTFIFO_FIFOSIZE_MASK);
 
 	/*
-	 * The LS1028A has a fixed length of 16 words. Although it supports the
-	 * RX/TXSIZE fields their encoding is different. Eg the reference manual
-	 * states 0b101 is 16 words.
+	 * The LS1021A and LS1028A have a fixed FIFO depth of 16 words.
+	 * Although they support the RX/TXSIZE fields, their encoding is
+	 * different. Eg the reference manual states 0b101 is 16 words.
 	 */
-	if (is_ls1028a_lpuart(sport)) {
+	if (is_layerscape_lpuart(sport)) {
 		sport->rxfifo_size = 16;
 		sport->txfifo_size = 16;
 		sport->port.fifosize = sport->txfifo_size;

drivers/tty/vt/keyboard.c

@@ -743,8 +743,13 @@ static void k_fn(struct vc_data *vc, unsigned char value, char up_flag)
 		return;
 
 	if ((unsigned)value < ARRAY_SIZE(func_table)) {
+		unsigned long flags;
+
+		spin_lock_irqsave(&func_buf_lock, flags);
 		if (func_table[value])
 			puts_queue(vc, func_table[value]);
+		spin_unlock_irqrestore(&func_buf_lock, flags);
+
 	} else
 		pr_err("k_fn called with value=%d\n", value);
 }
@@ -1991,13 +1996,11 @@ out:
 #undef s
 #undef v
 
-/* FIXME: This one needs untangling and locking */
+/* FIXME: This one needs untangling */
 int vt_do_kdgkb_ioctl(int cmd, struct kbsentry __user *user_kdgkb, int perm)
 {
 	struct kbsentry *kbs;
-	char *p;
 	u_char *q;
-	u_char __user *up;
 	int sz, fnw_sz;
 	int delta;
 	char *first_free, *fj, *fnw;
@@ -2023,23 +2026,19 @@ int vt_do_kdgkb_ioctl(int cmd, struct kbsentry __user *user_kdgkb, int perm)
 	i = array_index_nospec(kbs->kb_func, MAX_NR_FUNC);
 
 	switch (cmd) {
-	case KDGKBSENT:
-		sz = sizeof(kbs->kb_string) - 1; /* sz should have been
-						  a struct member */
-		up = user_kdgkb->kb_string;
-		p = func_table[i];
-		if(p)
-			for ( ; *p && sz; p++, sz--)
-				if (put_user(*p, up++)) {
-					ret = -EFAULT;
-					goto reterr;
-				}
-		if (put_user('\0', up)) {
-			ret = -EFAULT;
-			goto reterr;
-		}
-		kfree(kbs);
-		return ((p && *p) ? -EOVERFLOW : 0);
+	case KDGKBSENT: {
+		/* size should have been a struct member */
+		ssize_t len = sizeof(user_kdgkb->kb_string);
+
+		spin_lock_irqsave(&func_buf_lock, flags);
+		len = strlcpy(kbs->kb_string, func_table[i] ? : "", len);
+		spin_unlock_irqrestore(&func_buf_lock, flags);
+
+		ret = copy_to_user(user_kdgkb->kb_string, kbs->kb_string,
+				len + 1) ? -EFAULT : 0;
+
+		goto reterr;
+	}
 	case KDSKBSENT:
 		if (!perm) {
 			ret = -EPERM;

drivers/tty/vt/vt_ioctl.c

@@ -549,7 +549,7 @@ static int vt_io_fontreset(struct console_font_op *op)
 }
 
 static inline int do_unimap_ioctl(int cmd, struct unimapdesc __user *user_ud,
-		struct vc_data *vc)
+		bool perm, struct vc_data *vc)
 {
 	struct unimapdesc tmp;
 
@@ -557,9 +557,11 @@ static inline int do_unimap_ioctl(int cmd, struct unimapdesc __user *user_ud,
 		return -EFAULT;
 	switch (cmd) {
 	case PIO_UNIMAP:
+		if (!perm)
+			return -EPERM;
 		return con_set_unimap(vc, tmp.entry_ct, tmp.entries);
 	case GIO_UNIMAP:
-		if (fg_console != vc->vc_num)
+		if (!perm && fg_console != vc->vc_num)
 			return -EPERM;
 		return con_get_unimap(vc, tmp.entry_ct, &(user_ud->entry_ct),
 				tmp.entries);
@@ -639,10 +641,7 @@ static int vt_io_ioctl(struct vc_data *vc, unsigned int cmd, void __user *up,
 
 	case PIO_UNIMAP:
 	case GIO_UNIMAP:
-		if (!perm)
-			return -EPERM;
-
-		return do_unimap_ioctl(cmd, up, vc);
+		return do_unimap_ioctl(cmd, up, perm, vc);
 
 	default:
 		return -ENOIOCTLCMD;