tty/serial driver fixes for 6.11-rc3

Here are some small tty and serial driver fixes for reported problems
 for 6.11-rc3.  Included in here are:
  - sc16is7xx serial driver fixes
  - uartclk bugfix for a divide by zero issue
  - conmakehash userspace build issue fix
 
 All of these have been in linux-next for a while with no reported
 issues.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
 -----BEGIN PGP SIGNATURE-----
 
 iG0EABECAC0WIQT0tgzFv3jCIUoxPcsxR9QN2y37KQUCZri5gA8cZ3JlZ0Brcm9h
 aC5jb20ACgkQMUfUDdst+ylCCgCfS612Ty+xRL/CbTznTobArGq5hbMAoLT3hqkN
 1Mi7sbRC//FiN2HOFc8I
 =x19f
 -----END PGP SIGNATURE-----

Merge tag 'tty-6.11-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty / serial driver fixes from Greg KH:
 "Here are some small tty and serial driver fixes for reported problems
  for 6.11-rc3. Included in here are:

   - sc16is7xx serial driver fixes

   - uartclk bugfix for a divide by zero issue

   - conmakehash userspace build issue fix

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'tty-6.11-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
  tty: vt: conmakehash: cope with abs_srctree no longer in env
  serial: sc16is7xx: fix invalid FIFO access with special register set
  serial: sc16is7xx: fix TX fifo corruption
  serial: core: check uartclk for zero to avoid divide by zero

drivers/tty/serial/sc16is7xx.c

@@ -327,6 +327,7 @@ struct sc16is7xx_one {
 	struct kthread_work		reg_work;
 	struct kthread_delayed_work	ms_work;
 	struct sc16is7xx_one_config	config;
+	unsigned char			buf[SC16IS7XX_FIFO_SIZE]; /* Rx buffer. */
 	unsigned int			old_mctrl;
 	u8				old_lcr; /* Value before EFR access. */
 	bool				irda_mode;
@@ -340,7 +341,6 @@ struct sc16is7xx_port {
 	unsigned long			gpio_valid_mask;
 #endif
 	u8				mctrl_mask;
-	unsigned char			buf[SC16IS7XX_FIFO_SIZE];
 	struct kthread_worker		kworker;
 	struct task_struct		*kworker_task;
 	struct sc16is7xx_one		p[];
@@ -592,6 +592,8 @@ static int sc16is7xx_set_baud(struct uart_port *port, int baud)
 			      SC16IS7XX_MCR_CLKSEL_BIT,
 			      prescaler == 1 ? 0 : SC16IS7XX_MCR_CLKSEL_BIT);
 
+	mutex_lock(&one->efr_lock);
+
 	/* Backup LCR and access special register set (DLL/DLH) */
 	lcr = sc16is7xx_port_read(port, SC16IS7XX_LCR_REG);
 	sc16is7xx_port_write(port, SC16IS7XX_LCR_REG,
@@ -606,24 +608,26 @@ static int sc16is7xx_set_baud(struct uart_port *port, int baud)
 	/* Restore LCR and access to general register set */
 	sc16is7xx_port_write(port, SC16IS7XX_LCR_REG, lcr);
 
+	mutex_unlock(&one->efr_lock);
+
 	return DIV_ROUND_CLOSEST((clk / prescaler) / 16, div);
 }
 
 static void sc16is7xx_handle_rx(struct uart_port *port, unsigned int rxlen,
 				unsigned int iir)
 {
-	struct sc16is7xx_port *s = dev_get_drvdata(port->dev);
+	struct sc16is7xx_one *one = to_sc16is7xx_one(port, port);
 	unsigned int lsr = 0, bytes_read, i;
 	bool read_lsr = (iir == SC16IS7XX_IIR_RLSE_SRC) ? true : false;
 	u8 ch, flag;
 
-	if (unlikely(rxlen >= sizeof(s->buf))) {
+	if (unlikely(rxlen >= sizeof(one->buf))) {
 		dev_warn_ratelimited(port->dev,
 				     "ttySC%i: Possible RX FIFO overrun: %d\n",
 				     port->line, rxlen);
 		port->icount.buf_overrun++;
 		/* Ensure sanity of RX level */
-		rxlen = sizeof(s->buf);
+		rxlen = sizeof(one->buf);
 	}
 
 	while (rxlen) {
@@ -636,10 +640,10 @@ static void sc16is7xx_handle_rx(struct uart_port *port, unsigned int rxlen,
 			lsr = 0;
 
 		if (read_lsr) {
-			s->buf[0] = sc16is7xx_port_read(port, SC16IS7XX_RHR_REG);
+			one->buf[0] = sc16is7xx_port_read(port, SC16IS7XX_RHR_REG);
 			bytes_read = 1;
 		} else {
-			sc16is7xx_fifo_read(port, s->buf, rxlen);
+			sc16is7xx_fifo_read(port, one->buf, rxlen);
 			bytes_read = rxlen;
 		}
 
@@ -672,7 +676,7 @@ static void sc16is7xx_handle_rx(struct uart_port *port, unsigned int rxlen,
 		}
 
 		for (i = 0; i < bytes_read; ++i) {
-			ch = s->buf[i];
+			ch = one->buf[i];
 			if (uart_handle_sysrq_char(port, ch))
 				continue;
 
@@ -690,10 +694,10 @@ static void sc16is7xx_handle_rx(struct uart_port *port, unsigned int rxlen,
 
 static void sc16is7xx_handle_tx(struct uart_port *port)
 {
-	struct sc16is7xx_port *s = dev_get_drvdata(port->dev);
 	struct tty_port *tport = &port->state->port;
 	unsigned long flags;
 	unsigned int txlen;
+	unsigned char *tail;
 
 	if (unlikely(port->x_char)) {
 		sc16is7xx_port_write(port, SC16IS7XX_THR_REG, port->x_char);
@@ -718,8 +722,9 @@ static void sc16is7xx_handle_tx(struct uart_port *port)
 		txlen = 0;
 	}
 
-	txlen = uart_fifo_out(port, s->buf, txlen);
-	sc16is7xx_fifo_write(port, s->buf, txlen);
+	txlen = kfifo_out_linear_ptr(&tport->xmit_fifo, &tail, txlen);
+	sc16is7xx_fifo_write(port, tail, txlen);
+	uart_xmit_advance(port, txlen);
 
 	uart_port_lock_irqsave(port, &flags);
 	if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS)

drivers/tty/serial/serial_core.c

@@ -881,6 +881,14 @@ static int uart_set_info(struct tty_struct *tty, struct tty_port *port,
 	new_flags = (__force upf_t)new_info->flags;
 	old_custom_divisor = uport->custom_divisor;
 
+	if (!(uport->flags & UPF_FIXED_PORT)) {
+		unsigned int uartclk = new_info->baud_base * 16;
+		/* check needs to be done here before other settings made */
+		if (uartclk == 0) {
+			retval = -EINVAL;
+			goto exit;
+		}
+	}
 	if (!capable(CAP_SYS_ADMIN)) {
 		retval = -EPERM;
 		if (change_irq || change_port ||

drivers/tty/vt/conmakehash.c

@@ -11,6 +11,8 @@
  * Copyright (C) 1995-1997 H. Peter Anvin
  */
 
+#include <libgen.h>
+#include <linux/limits.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <sysexits.h>
@@ -76,8 +78,8 @@ static void addpair(int fp, int un)
 int main(int argc, char *argv[])
 {
   FILE *ctbl;
-  const char *tblname, *rel_tblname;
-  const char *abs_srctree;
+  const char *tblname;
+  char base_tblname[PATH_MAX];
   char buffer[65536];
   int fontlen;
   int i, nuni, nent;
@@ -102,16 +104,6 @@ int main(int argc, char *argv[])
 	}
     }
 
-  abs_srctree = getenv("abs_srctree");
-  if (abs_srctree && !strncmp(abs_srctree, tblname, strlen(abs_srctree)))
-    {
-      rel_tblname = tblname + strlen(abs_srctree);
-      while (*rel_tblname == '/')
-	++rel_tblname;
-    }
-  else
-    rel_tblname = tblname;
-
   /* For now we assume the default font is always 256 characters. */
   fontlen = 256;
 
@@ -253,6 +245,8 @@ int main(int argc, char *argv[])
   for ( i = 0 ; i < fontlen ; i++ )
     nuni += unicount[i];
 
+  strncpy(base_tblname, tblname, PATH_MAX);
+  base_tblname[PATH_MAX - 1] = 0;
   printf("\
 /*\n\
  * Do not edit this file; it was automatically generated by\n\
@@ -264,7 +258,7 @@ int main(int argc, char *argv[])
 #include <linux/types.h>\n\
 \n\
 u8 dfont_unicount[%d] = \n\
-{\n\t", rel_tblname, fontlen);
+{\n\t", basename(base_tblname), fontlen);
 
   for ( i = 0 ; i < fontlen ; i++ )
     {