From 4f22e0fa01f5b33c9df42863980b8cfac200af2f Mon Sep 17 00:00:00 2001 From: "Tobin C. Harding" Date: Tue, 7 Mar 2017 20:57:03 +1100 Subject: staging: dgnc: audit goto's in dgnc_tty TODO file requests fix up of error handling. Audit dgnc_mgmt.c and fix all return paths to be uniform and inline with kernel coding style. Signed-off-by: Tobin C. Harding Signed-off-by: Greg Kroah-Hartman --- drivers/staging/dgnc/dgnc_tty.c | 219 ++++++++++++++++++++-------------------- 1 file changed, 112 insertions(+), 107 deletions(-) (limited to 'drivers/staging/dgnc') diff --git a/drivers/staging/dgnc/dgnc_tty.c b/drivers/staging/dgnc/dgnc_tty.c index cde00e3702fa..ffbe5a22169f 100644 --- a/drivers/staging/dgnc/dgnc_tty.c +++ b/drivers/staging/dgnc/dgnc_tty.c @@ -143,7 +143,6 @@ int dgnc_tty_register(struct dgnc_board *brd) TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV | TTY_DRIVER_HARDWARE_BREAK); - if (IS_ERR(brd->serial_driver)) return PTR_ERR(brd->serial_driver); @@ -181,7 +180,6 @@ int dgnc_tty_register(struct dgnc_board *brd) TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV | TTY_DRIVER_HARDWARE_BREAK); - if (IS_ERR(brd->print_driver)) { rc = PTR_ERR(brd->print_driver); goto unregister_serial_driver; @@ -220,7 +218,6 @@ unregister_serial_driver: tty_unregister_driver(brd->serial_driver); free_serial_driver: put_tty_driver(brd->serial_driver); - return rc; } @@ -241,6 +238,7 @@ void dgnc_tty_unregister(struct dgnc_board *brd) int dgnc_tty_init(struct dgnc_board *brd) { int i; + int rc; void __iomem *vaddr; struct channel_t *ch; @@ -260,8 +258,10 @@ int dgnc_tty_init(struct dgnc_board *brd) */ brd->channels[i] = kzalloc(sizeof(*brd->channels[i]), GFP_KERNEL); - if (!brd->channels[i]) + if (!brd->channels[i]) { + rc = -ENOMEM; goto err_free_channels; + } } ch = brd->channels[0]; @@ -319,7 +319,7 @@ err_free_channels: kfree(brd->channels[i]); brd->channels[i] = NULL; } - return -ENOMEM; + return rc; } /* @@ -914,7 +914,6 @@ static int dgnc_tty_open(struct tty_struct *tty, struct file *file) */ rc = wait_event_interruptible(brd->state_wait, (brd->state & BOARD_READY)); - if (rc) return rc; @@ -922,14 +921,14 @@ static int dgnc_tty_open(struct tty_struct *tty, struct file *file) /* If opened device is greater than our number of ports, bail. */ if (PORT_NUM(minor) >= brd->nasync) { - spin_unlock_irqrestore(&brd->bd_lock, flags); - return -ENXIO; + rc = -ENXIO; + goto err_brd_unlock; } ch = brd->channels[PORT_NUM(minor)]; if (!ch) { - spin_unlock_irqrestore(&brd->bd_lock, flags); - return -ENXIO; + rc = -ENXIO; + goto err_brd_unlock; } /* Drop board lock */ @@ -946,8 +945,8 @@ static int dgnc_tty_open(struct tty_struct *tty, struct file *file) un = &brd->channels[PORT_NUM(minor)]->ch_pun; un->un_type = DGNC_PRINT; } else { - spin_unlock_irqrestore(&ch->ch_lock, flags); - return -ENXIO; + rc = -ENXIO; + goto err_ch_unlock; } /* @@ -959,7 +958,6 @@ static int dgnc_tty_open(struct tty_struct *tty, struct file *file) rc = wait_event_interruptible(ch->ch_flags_wait, ((ch->ch_flags & CH_OPENING) == 0)); - /* If ret is non-zero, user ctrl-c'ed us */ if (rc) return -EINTR; @@ -975,7 +973,6 @@ static int dgnc_tty_open(struct tty_struct *tty, struct file *file) ch->ch_flags_wait, (((ch->ch_tun.un_flags | ch->ch_pun.un_flags) & UN_CLOSING) == 0)); - /* If ret is non-zero, user ctrl-c'ed us */ if (rc) return -EINTR; @@ -1014,7 +1011,6 @@ static int dgnc_tty_open(struct tty_struct *tty, struct file *file) kfree(ch->ch_rqueue); kfree(ch->ch_equeue); kfree(ch->ch_wqueue); - return -ENOMEM; } @@ -1082,6 +1078,14 @@ static int dgnc_tty_open(struct tty_struct *tty, struct file *file) spin_unlock_irqrestore(&ch->ch_lock, flags); return rc; + +err_brd_unlock: + spin_unlock_irqrestore(&brd->bd_lock, flags); + return rc; +err_ch_unlock: + spin_unlock_irqrestore(&ch->ch_lock, flags); + return rc; + } /* @@ -1093,7 +1097,7 @@ static int dgnc_block_til_ready(struct tty_struct *tty, struct file *file, struct channel_t *ch) { - int retval = 0; + int rc = 0; struct un_t *un = tty->driver_data; unsigned long flags; uint old_flags = 0; @@ -1115,13 +1119,13 @@ static int dgnc_block_til_ready(struct tty_struct *tty, * bail with error. */ if (ch->ch_bd->state == BOARD_FAILED) { - retval = -ENXIO; + rc = -ENXIO; break; } /* If tty was hung up, break out of loop and set error. */ if (tty_hung_up_p(file)) { - retval = -EAGAIN; + rc = -EAGAIN; break; } @@ -1146,7 +1150,7 @@ static int dgnc_block_til_ready(struct tty_struct *tty, break; if (tty_io_error(tty)) { - retval = -EIO; + rc = -EIO; break; } @@ -1165,7 +1169,7 @@ static int dgnc_block_til_ready(struct tty_struct *tty, * Leave loop with error set. */ if (signal_pending(current)) { - retval = -ERESTARTSYS; + rc = -ERESTARTSYS; break; } @@ -1189,12 +1193,12 @@ static int dgnc_block_til_ready(struct tty_struct *tty, * from the current value. */ if (sleep_on_un_flags) - retval = wait_event_interruptible + rc = wait_event_interruptible (un->un_flags_wait, (old_flags != (ch->ch_tun.un_flags | ch->ch_pun.un_flags))); else - retval = wait_event_interruptible( + rc = wait_event_interruptible( ch->ch_flags_wait, (old_flags != ch->ch_flags)); @@ -1208,8 +1212,7 @@ static int dgnc_block_til_ready(struct tty_struct *tty, ch->ch_wopen--; spin_unlock_irqrestore(&ch->ch_lock, flags); - - return retval; + return rc; } /* @@ -1375,7 +1378,7 @@ static int dgnc_tty_chars_in_buffer(struct tty_struct *tty) ushort thead; ushort ttail; uint tmask; - uint chars = 0; + uint chars; unsigned long flags; if (!tty) @@ -1397,16 +1400,14 @@ static int dgnc_tty_chars_in_buffer(struct tty_struct *tty) spin_unlock_irqrestore(&ch->ch_lock, flags); - if (ttail == thead) { + if (ttail == thead) chars = 0; - } else { - if (thead >= ttail) - chars = thead - ttail; - else - chars = thead - ttail + WQUEUESIZE; - } + else if (thead > ttail) + chars = thead - ttail; + else + chars = thead - ttail + WQUEUESIZE; - return chars; + return (int)chars; } /* @@ -1419,6 +1420,8 @@ static int dgnc_tty_chars_in_buffer(struct tty_struct *tty) */ static int dgnc_maxcps_room(struct channel_t *ch, int bytes_available) { + int rc = bytes_available; + if (ch->ch_digi.digi_maxcps > 0 && ch->ch_digi.digi_bufsize > 0) { int cps_limit = 0; unsigned long current_time = jiffies; @@ -1439,16 +1442,16 @@ static int dgnc_maxcps_room(struct channel_t *ch, int bytes_available) cps_limit = 0; } - bytes_available = min(cps_limit, bytes_available); + rc = min(cps_limit, bytes_available); } - return bytes_available; + return rc; } /* * dgnc_tty_write_room() * - * Return space available in Tx buffer + * Return room available in Tx buffer */ static int dgnc_tty_write_room(struct tty_struct *tty) { @@ -1457,7 +1460,7 @@ static int dgnc_tty_write_room(struct tty_struct *tty) ushort head; ushort tail; ushort tmask; - int ret = 0; + int room = 0; unsigned long flags; if (!tty) @@ -1477,33 +1480,32 @@ static int dgnc_tty_write_room(struct tty_struct *tty) head = (ch->ch_w_head) & tmask; tail = (ch->ch_w_tail) & tmask; - ret = tail - head - 1; - if (ret < 0) - ret += WQUEUESIZE; + room = tail - head - 1; + if (room < 0) + room += WQUEUESIZE; /* Limit printer to maxcps */ if (un->un_type != DGNC_PRINT) - ret = dgnc_maxcps_room(ch, ret); + room = dgnc_maxcps_room(ch, room); /* - * If we are printer device, leave space for + * If we are printer device, leave room for * possibly both the on and off strings. */ if (un->un_type == DGNC_PRINT) { if (!(ch->ch_flags & CH_PRON)) - ret -= ch->ch_digi.digi_onlen; - ret -= ch->ch_digi.digi_offlen; + room -= ch->ch_digi.digi_onlen; + room -= ch->ch_digi.digi_offlen; } else { if (ch->ch_flags & CH_PRON) - ret -= ch->ch_digi.digi_offlen; + room -= ch->ch_digi.digi_offlen; } - if (ret < 0) - ret = 0; + if (room < 0) + room = 0; spin_unlock_irqrestore(&ch->ch_lock, flags); - - return ret; + return room; } /* @@ -1657,7 +1659,6 @@ static int dgnc_tty_write(struct tty_struct *tty, return count; exit_retry: - spin_unlock_irqrestore(&ch->ch_lock, flags); return 0; } @@ -1668,20 +1669,20 @@ static int dgnc_tty_tiocmget(struct tty_struct *tty) { struct channel_t *ch; struct un_t *un; - int result = -EIO; + int rc = -EIO; unsigned char mstat = 0; unsigned long flags; if (!tty || tty->magic != TTY_MAGIC) - return result; + return rc; un = tty->driver_data; if (!un || un->magic != DGNC_UNIT_MAGIC) - return result; + return rc; ch = un->un_ch; if (!ch || ch->magic != DGNC_CHANNEL_MAGIC) - return result; + return rc; spin_lock_irqsave(&ch->ch_lock, flags); @@ -1689,22 +1690,22 @@ static int dgnc_tty_tiocmget(struct tty_struct *tty) spin_unlock_irqrestore(&ch->ch_lock, flags); - result = 0; + rc = 0; if (mstat & UART_MCR_DTR) - result |= TIOCM_DTR; + rc |= TIOCM_DTR; if (mstat & UART_MCR_RTS) - result |= TIOCM_RTS; + rc |= TIOCM_RTS; if (mstat & UART_MSR_CTS) - result |= TIOCM_CTS; + rc |= TIOCM_CTS; if (mstat & UART_MSR_DSR) - result |= TIOCM_DSR; + rc |= TIOCM_DSR; if (mstat & UART_MSR_RI) - result |= TIOCM_RI; + rc |= TIOCM_RI; if (mstat & UART_MSR_DCD) - result |= TIOCM_CD; + rc |= TIOCM_CD; - return result; + return rc; } /* @@ -1719,23 +1720,23 @@ static int dgnc_tty_tiocmset(struct tty_struct *tty, struct dgnc_board *bd; struct channel_t *ch; struct un_t *un; - int ret = -EIO; + int rc = -EIO; unsigned long flags; if (!tty || tty->magic != TTY_MAGIC) - return ret; + return rc; un = tty->driver_data; if (!un || un->magic != DGNC_UNIT_MAGIC) - return ret; + return rc; ch = un->un_ch; if (!ch || ch->magic != DGNC_CHANNEL_MAGIC) - return ret; + return rc; bd = ch->ch_bd; if (!bd || bd->magic != DGNC_BOARD_MAGIC) - return ret; + return rc; spin_lock_irqsave(&ch->ch_lock, flags); @@ -1768,23 +1769,23 @@ static int dgnc_tty_send_break(struct tty_struct *tty, int msec) struct dgnc_board *bd; struct channel_t *ch; struct un_t *un; - int ret = -EIO; + int rc = -EIO; unsigned long flags; if (!tty || tty->magic != TTY_MAGIC) - return ret; + return rc; un = tty->driver_data; if (!un || un->magic != DGNC_UNIT_MAGIC) - return ret; + return rc; ch = un->un_ch; if (!ch || ch->magic != DGNC_CHANNEL_MAGIC) - return ret; + return rc; bd = ch->ch_bd; if (!bd || bd->magic != DGNC_BOARD_MAGIC) - return ret; + return rc; switch (msec) { case -1: @@ -1876,11 +1877,11 @@ static void dgnc_tty_send_xchar(struct tty_struct *tty, char c) static inline int dgnc_get_mstat(struct channel_t *ch) { unsigned char mstat; - int result = 0; + int rc = -ENXIO; unsigned long flags; if (!ch || ch->magic != DGNC_CHANNEL_MAGIC) - return -ENXIO; + return rc; spin_lock_irqsave(&ch->ch_lock, flags); @@ -1888,20 +1889,22 @@ static inline int dgnc_get_mstat(struct channel_t *ch) spin_unlock_irqrestore(&ch->ch_lock, flags); + rc = 0; + if (mstat & UART_MCR_DTR) - result |= TIOCM_DTR; + rc |= TIOCM_DTR; if (mstat & UART_MCR_RTS) - result |= TIOCM_RTS; + rc |= TIOCM_RTS; if (mstat & UART_MSR_CTS) - result |= TIOCM_CTS; + rc |= TIOCM_CTS; if (mstat & UART_MSR_DSR) - result |= TIOCM_DSR; + rc |= TIOCM_DSR; if (mstat & UART_MSR_RI) - result |= TIOCM_RI; + rc |= TIOCM_RI; if (mstat & UART_MSR_DCD) - result |= TIOCM_CD; + rc |= TIOCM_CD; - return result; + return rc; } /* Return modem signals to ld. */ @@ -1921,13 +1924,13 @@ static int dgnc_set_modem_info(struct channel_t *ch, unsigned int command, unsigned int __user *value) { - int ret = -ENXIO; + int rc; unsigned int arg = 0; unsigned long flags; - ret = get_user(arg, value); - if (ret) - return ret; + rc = get_user(arg, value); + if (rc) + return rc; switch (command) { case TIOCMBIS: @@ -1987,20 +1990,21 @@ static int dgnc_tty_digigeta(struct tty_struct *tty, struct un_t *un; struct digi_t tmp; unsigned long flags; + int rc = -EFAULT; if (!retinfo) - return -EFAULT; + return rc; if (!tty || tty->magic != TTY_MAGIC) - return -EFAULT; + return rc; un = tty->driver_data; if (!un || un->magic != DGNC_UNIT_MAGIC) - return -EFAULT; + return rc; ch = un->un_ch; if (!ch || ch->magic != DGNC_CHANNEL_MAGIC) - return -EFAULT; + return rc; memset(&tmp, 0, sizeof(tmp)); @@ -2009,7 +2013,7 @@ static int dgnc_tty_digigeta(struct tty_struct *tty, spin_unlock_irqrestore(&ch->ch_lock, flags); if (copy_to_user(retinfo, &tmp, sizeof(*retinfo))) - return -EFAULT; + return rc; return 0; } @@ -2027,24 +2031,25 @@ static int dgnc_tty_digiseta(struct tty_struct *tty, struct un_t *un; struct digi_t new_digi; unsigned long flags; + int rc = -EFAULT; if (!tty || tty->magic != TTY_MAGIC) - return -EFAULT; + return rc; un = tty->driver_data; if (!un || un->magic != DGNC_UNIT_MAGIC) - return -EFAULT; + return rc; ch = un->un_ch; if (!ch || ch->magic != DGNC_CHANNEL_MAGIC) - return -EFAULT; + return rc; bd = ch->ch_bd; if (!bd || bd->magic != DGNC_BOARD_MAGIC) - return -EFAULT; + return rc; if (copy_from_user(&new_digi, new_info, sizeof(new_digi))) - return -EFAULT; + return rc; spin_lock_irqsave(&ch->ch_lock, flags); @@ -2353,32 +2358,32 @@ static int dgnc_tty_ioctl(struct tty_struct *tty, unsigned int cmd, struct board_ops *ch_bd_ops; struct channel_t *ch; struct un_t *un; - int rc; + int rc = -ENODEV; unsigned long flags; void __user *uarg = (void __user *)arg; if (!tty || tty->magic != TTY_MAGIC) - return -ENODEV; + return rc; un = tty->driver_data; if (!un || un->magic != DGNC_UNIT_MAGIC) - return -ENODEV; + return rc; ch = un->un_ch; if (!ch || ch->magic != DGNC_CHANNEL_MAGIC) - return -ENODEV; + return rc; bd = ch->ch_bd; if (!bd || bd->magic != DGNC_BOARD_MAGIC) - return -ENODEV; + return rc; ch_bd_ops = bd->bd_ops; spin_lock_irqsave(&ch->ch_lock, flags); if (un->un_open_count <= 0) { - spin_unlock_irqrestore(&ch->ch_lock, flags); - return -EIO; + rc = -EIO; + goto err_unlock; } switch (cmd) { @@ -2504,10 +2509,8 @@ static int dgnc_tty_ioctl(struct tty_struct *tty, unsigned int cmd, * also. */ rc = tty_check_change(tty); - if (rc) { - spin_unlock_irqrestore(&ch->ch_lock, flags); - return rc; - } + if (rc) + goto err_unlock; if ((arg == TCIFLUSH) || (arg == TCIOFLUSH)) { ch->ch_r_head = ch->ch_r_tail; @@ -2588,7 +2591,6 @@ static int dgnc_tty_ioctl(struct tty_struct *tty, unsigned int cmd, if (cmd == (DIGI_SETAW)) { spin_unlock_irqrestore(&ch->ch_lock, flags); rc = ch_bd_ops->drain(tty, 0); - if (rc) return -EINTR; @@ -2787,4 +2789,7 @@ static int dgnc_tty_ioctl(struct tty_struct *tty, unsigned int cmd, return -ENOIOCTLCMD; } +err_unlock: + spin_unlock_irqrestore(&ch->ch_lock, flags); + return rc; } -- cgit v1.2.3-59-g8ed1b