diff options
author | Frans Klaver <frans.klaver@xsens.com> | 2014-09-25 11:19:51 +0200 |
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committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2014-09-28 21:23:45 -0400 |
commit | dc3187564e61260f49eceb21a4e7eb5e4428e90a (patch) | |
tree | 95b52a8c22178e7c53bae7d5eab23120e6812fb5 /drivers/tty/serial | |
parent | fb498df0787db0fb10a4a2cf91d0d3da13cc18f7 (diff) | |
download | linux-dc3187564e61260f49eceb21a4e7eb5e4428e90a.tar.gz |
tty: omap-serial: fix division by zero
If the chosen baud rate is large enough (e.g. 3.5 megabaud), the calculated n values in serial_omap_is_baud_mode16() may become 0. This causes a division by zero when calculating the difference between calculated and desired baud rates. To prevent this, cap the n13 and n16 values on 1. Division by zero in kernel. [<c00132e0>] (unwind_backtrace) from [<c00112ec>] (show_stack+0x10/0x14) [<c00112ec>] (show_stack) from [<c01ed7bc>] (Ldiv0+0x8/0x10) [<c01ed7bc>] (Ldiv0) from [<c023805c>] (serial_omap_baud_is_mode16+0x4c/0x68) [<c023805c>] (serial_omap_baud_is_mode16) from [<c02396b4>] (serial_omap_set_termios+0x90/0x8d8) [<c02396b4>] (serial_omap_set_termios) from [<c0230a0c>] (uart_change_speed+0xa4/0xa8) [<c0230a0c>] (uart_change_speed) from [<c0231798>] (uart_set_termios+0xa0/0x1fc) [<c0231798>] (uart_set_termios) from [<c022bb44>] (tty_set_termios+0x248/0x2c0) [<c022bb44>] (tty_set_termios) from [<c022c17c>] (set_termios+0x248/0x29c) [<c022c17c>] (set_termios) from [<c022c3e4>] (tty_mode_ioctl+0x1c8/0x4e8) [<c022c3e4>] (tty_mode_ioctl) from [<c0227e70>] (tty_ioctl+0xa94/0xb18) [<c0227e70>] (tty_ioctl) from [<c00cf45c>] (do_vfs_ioctl+0x4a0/0x560) [<c00cf45c>] (do_vfs_ioctl) from [<c00cf568>] (SyS_ioctl+0x4c/0x74) [<c00cf568>] (SyS_ioctl) from [<c000e480>] (ret_fast_syscall+0x0/0x30) Signed-off-by: Frans Klaver <frans.klaver@xsens.com> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/tty/serial')
-rw-r--r-- | drivers/tty/serial/omap-serial.c | 12 |
1 files changed, 10 insertions, 2 deletions
diff --git a/drivers/tty/serial/omap-serial.c b/drivers/tty/serial/omap-serial.c index d017cec8a34a..e454b7c2ecd9 100644 --- a/drivers/tty/serial/omap-serial.c +++ b/drivers/tty/serial/omap-serial.c @@ -254,8 +254,16 @@ serial_omap_baud_is_mode16(struct uart_port *port, unsigned int baud) { unsigned int n13 = port->uartclk / (13 * baud); unsigned int n16 = port->uartclk / (16 * baud); - int baudAbsDiff13 = baud - (port->uartclk / (13 * n13)); - int baudAbsDiff16 = baud - (port->uartclk / (16 * n16)); + int baudAbsDiff13; + int baudAbsDiff16; + + if (n13 == 0) + n13 = 1; + if (n16 == 0) + n16 = 1; + + baudAbsDiff13 = baud - (port->uartclk / (13 * n13)); + baudAbsDiff16 = baud - (port->uartclk / (16 * n16)); if (baudAbsDiff13 < 0) baudAbsDiff13 = -baudAbsDiff13; if (baudAbsDiff16 < 0) |