synclink fix ldisc buffer argument
Fix call to line discipline receive_buf by synclink drivers.
Dummy flag buffer argument is ignored by N_HDLC line discipline but might
be of insufficient size if accessed by a different line discipline
selected by mistake. flag buffer allocation now matches max size of data
buffer. Unused char_buf buffers are removed.
Signed-off-by: Paul Fulghum <paulkf@microgate.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/tty/synclink_gt.c b/drivers/tty/synclink_gt.c
index aba1e59..62a0db7 100644
--- a/drivers/tty/synclink_gt.c
+++ b/drivers/tty/synclink_gt.c
@@ -317,8 +317,7 @@
unsigned char *tx_buf;
int tx_count;
- char flag_buf[MAX_ASYNC_BUFFER_SIZE];
- char char_buf[MAX_ASYNC_BUFFER_SIZE];
+ char *flag_buf;
bool drop_rts_on_tx_done;
struct _input_signal_events input_signal_events;
@@ -3355,11 +3354,24 @@
return retval;
}
+/*
+ * allocate buffers used for calling line discipline receive_buf
+ * directly in synchronous mode
+ * note: add 5 bytes to max frame size to allow appending
+ * 32-bit CRC and status byte when configured to do so
+ */
static int alloc_tmp_rbuf(struct slgt_info *info)
{
info->tmp_rbuf = kmalloc(info->max_frame_size + 5, GFP_KERNEL);
if (info->tmp_rbuf == NULL)
return -ENOMEM;
+ /* unused flag buffer to satisfy receive_buf calling interface */
+ info->flag_buf = kzalloc(info->max_frame_size + 5, GFP_KERNEL);
+ if (!info->flag_buf) {
+ kfree(info->tmp_rbuf);
+ info->tmp_rbuf = NULL;
+ return -ENOMEM;
+ }
return 0;
}
@@ -3367,6 +3379,8 @@
{
kfree(info->tmp_rbuf);
info->tmp_rbuf = NULL;
+ kfree(info->flag_buf);
+ info->flag_buf = NULL;
}
/*