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-rw-r--r--drivers/tty/pty.c64
-rw-r--r--drivers/tty/serial/8250/8250_core.c23
-rw-r--r--drivers/tty/serial/amba-pl011.c37
-rw-r--r--drivers/tty/tty_io.c3
4 files changed, 66 insertions, 61 deletions
diff --git a/drivers/tty/pty.c b/drivers/tty/pty.c
index 284749fb0f6b..a6d5164c33a9 100644
--- a/drivers/tty/pty.c
+++ b/drivers/tty/pty.c
@@ -69,13 +69,8 @@ static void pty_close(struct tty_struct *tty, struct file *filp)
#ifdef CONFIG_UNIX98_PTYS
if (tty->driver == ptm_driver) {
mutex_lock(&devpts_mutex);
- if (tty->link->driver_data) {
- struct path *path = tty->link->driver_data;
-
- devpts_pty_kill(path->dentry);
- path_put(path);
- kfree(path);
- }
+ if (tty->link->driver_data)
+ devpts_pty_kill(tty->link->driver_data);
mutex_unlock(&devpts_mutex);
}
#endif
@@ -607,25 +602,24 @@ static inline void legacy_pty_init(void) { }
static struct cdev ptmx_cdev;
/**
- * pty_open_peer - open the peer of a pty
- * @tty: the peer of the pty being opened
+ * ptm_open_peer - open the peer of a pty
+ * @master: the open struct file of the ptmx device node
+ * @tty: the master of the pty being opened
+ * @flags: the flags for open
*
- * Open the cached dentry in tty->link, providing a safe way for userspace
- * to get the slave end of a pty (where they have the master fd and cannot
- * access or trust the mount namespace /dev/pts was mounted inside).
+ * Provide a race free way for userspace to open the slave end of a pty
+ * (where they have the master fd and cannot access or trust the mount
+ * namespace /dev/pts was mounted inside).
*/
-static struct file *pty_open_peer(struct tty_struct *tty, int flags)
-{
- if (tty->driver->subtype != PTY_TYPE_MASTER)
- return ERR_PTR(-EIO);
- return dentry_open(tty->link->driver_data, flags, current_cred());
-}
-
-static int pty_get_peer(struct tty_struct *tty, int flags)
+int ptm_open_peer(struct file *master, struct tty_struct *tty, int flags)
{
int fd = -1;
- struct file *filp = NULL;
+ struct file *filp;
int retval = -EINVAL;
+ struct path path;
+
+ if (tty->driver != ptm_driver)
+ return -EIO;
fd = get_unused_fd_flags(0);
if (fd < 0) {
@@ -633,7 +627,16 @@ static int pty_get_peer(struct tty_struct *tty, int flags)
goto err;
}
- filp = pty_open_peer(tty, flags);
+ /* Compute the slave's path */
+ path.mnt = devpts_mntget(master, tty->driver_data);
+ if (IS_ERR(path.mnt)) {
+ retval = PTR_ERR(path.mnt);
+ goto err_put;
+ }
+ path.dentry = tty->link->driver_data;
+
+ filp = dentry_open(&path, flags, current_cred());
+ mntput(path.mnt);
if (IS_ERR(filp)) {
retval = PTR_ERR(filp);
goto err_put;
@@ -662,8 +665,6 @@ static int pty_unix98_ioctl(struct tty_struct *tty,
return pty_get_pktmode(tty, (int __user *)arg);
case TIOCGPTN: /* Get PT Number */
return put_user(tty->index, (unsigned int __user *)arg);
- case TIOCGPTPEER: /* Open the other end */
- return pty_get_peer(tty, (int) arg);
case TIOCSIG: /* Send signal to other side of pty */
return pty_signal(tty, (int) arg);
}
@@ -791,7 +792,6 @@ static int ptmx_open(struct inode *inode, struct file *filp)
{
struct pts_fs_info *fsi;
struct tty_struct *tty;
- struct path *pts_path;
struct dentry *dentry;
int retval;
int index;
@@ -845,26 +845,16 @@ static int ptmx_open(struct inode *inode, struct file *filp)
retval = PTR_ERR(dentry);
goto err_release;
}
- /* We need to cache a fake path for TIOCGPTPEER. */
- pts_path = kmalloc(sizeof(struct path), GFP_KERNEL);
- if (!pts_path)
- goto err_release;
- pts_path->mnt = filp->f_path.mnt;
- pts_path->dentry = dentry;
- path_get(pts_path);
- tty->link->driver_data = pts_path;
+ tty->link->driver_data = dentry;
retval = ptm_driver->ops->open(tty, filp);
if (retval)
- goto err_path_put;
+ goto err_release;
tty_debug_hangup(tty, "opening (count=%d)\n", tty->count);
tty_unlock(tty);
return 0;
-err_path_put:
- path_put(pts_path);
- kfree(pts_path);
err_release:
tty_unlock(tty);
// This will also put-ref the fsi
diff --git a/drivers/tty/serial/8250/8250_core.c b/drivers/tty/serial/8250/8250_core.c
index b5def356af63..1aab3010fbfa 100644
--- a/drivers/tty/serial/8250/8250_core.c
+++ b/drivers/tty/serial/8250/8250_core.c
@@ -1043,13 +1043,24 @@ int serial8250_register_8250_port(struct uart_8250_port *up)
if (up->dl_write)
uart->dl_write = up->dl_write;
- if (serial8250_isa_config != NULL)
- serial8250_isa_config(0, &uart->port,
- &uart->capabilities);
+ if (uart->port.type != PORT_8250_CIR) {
+ if (serial8250_isa_config != NULL)
+ serial8250_isa_config(0, &uart->port,
+ &uart->capabilities);
+
+ ret = uart_add_one_port(&serial8250_reg,
+ &uart->port);
+ if (ret == 0)
+ ret = uart->port.line;
+ } else {
+ dev_info(uart->port.dev,
+ "skipping CIR port at 0x%lx / 0x%llx, IRQ %d\n",
+ uart->port.iobase,
+ (unsigned long long)uart->port.mapbase,
+ uart->port.irq);
- ret = uart_add_one_port(&serial8250_reg, &uart->port);
- if (ret == 0)
- ret = uart->port.line;
+ ret = 0;
+ }
}
mutex_unlock(&serial_mutex);
diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c
index 8a857bb34fbb..1888d168a41c 100644
--- a/drivers/tty/serial/amba-pl011.c
+++ b/drivers/tty/serial/amba-pl011.c
@@ -142,15 +142,7 @@ static struct vendor_data vendor_sbsa = {
.fixed_options = true,
};
-/*
- * Erratum 44 for QDF2432v1 and QDF2400v1 SoCs describes the BUSY bit as
- * occasionally getting stuck as 1. To avoid the potential for a hang, check
- * TXFE == 0 instead of BUSY == 1. This may not be suitable for all UART
- * implementations, so only do so if an affected platform is detected in
- * parse_spcr().
- */
-static bool qdf2400_e44_present = false;
-
+#ifdef CONFIG_ACPI_SPCR_TABLE
static struct vendor_data vendor_qdt_qdf2400_e44 = {
.reg_offset = pl011_std_offsets,
.fr_busy = UART011_FR_TXFE,
@@ -165,6 +157,7 @@ static struct vendor_data vendor_qdt_qdf2400_e44 = {
.always_enabled = true,
.fixed_options = true,
};
+#endif
static u16 pl011_st_offsets[REG_ARRAY_SIZE] = {
[REG_DR] = UART01x_DR,
@@ -2375,12 +2368,14 @@ static int __init pl011_console_match(struct console *co, char *name, int idx,
resource_size_t addr;
int i;
- if (strcmp(name, "qdf2400_e44") == 0) {
- pr_info_once("UART: Working around QDF2400 SoC erratum 44");
- qdf2400_e44_present = true;
- } else if (strcmp(name, "pl011") != 0) {
+ /*
+ * Systems affected by the Qualcomm Technologies QDF2400 E44 erratum
+ * have a distinct console name, so make sure we check for that.
+ * The actual implementation of the erratum occurs in the probe
+ * function.
+ */
+ if ((strcmp(name, "qdf2400_e44") != 0) && (strcmp(name, "pl011") != 0))
return -ENODEV;
- }
if (uart_parse_earlycon(options, &iotype, &addr, &options))
return -ENODEV;
@@ -2734,11 +2729,17 @@ static int sbsa_uart_probe(struct platform_device *pdev)
}
uap->port.irq = ret;
- uap->reg_offset = vendor_sbsa.reg_offset;
- uap->vendor = qdf2400_e44_present ?
- &vendor_qdt_qdf2400_e44 : &vendor_sbsa;
+#ifdef CONFIG_ACPI_SPCR_TABLE
+ if (qdf2400_e44_present) {
+ dev_info(&pdev->dev, "working around QDF2400 SoC erratum 44\n");
+ uap->vendor = &vendor_qdt_qdf2400_e44;
+ } else
+#endif
+ uap->vendor = &vendor_sbsa;
+
+ uap->reg_offset = uap->vendor->reg_offset;
uap->fifosize = 32;
- uap->port.iotype = vendor_sbsa.access_32b ? UPIO_MEM32 : UPIO_MEM;
+ uap->port.iotype = uap->vendor->access_32b ? UPIO_MEM32 : UPIO_MEM;
uap->port.ops = &sbsa_uart_pops;
uap->fixed_baud = baudrate;
diff --git a/drivers/tty/tty_io.c b/drivers/tty/tty_io.c
index 974b13d24401..10c4038c0e8d 100644
--- a/drivers/tty/tty_io.c
+++ b/drivers/tty/tty_io.c
@@ -2518,6 +2518,9 @@ long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
case TIOCSSERIAL:
tty_warn_deprecated_flags(p);
break;
+ case TIOCGPTPEER:
+ /* Special because the struct file is needed */
+ return ptm_open_peer(file, tty, (int)arg);
default:
retval = tty_jobctrl_ioctl(tty, real_tty, file, cmd, arg);
if (retval != -ENOIOCTLCMD)
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.