1 files changed, 38 insertions, 17 deletions

diff --git a/drivers/char/n_tty.c b/drivers/char/n_tty.c
index 30b0426b3788..4b1e96b65ab0 100644
--- a/drivers/char/n_tty.c
+++ b/drivers/char/n_tty.c
@@ -1107,6 +1107,7 @@ static inline void n_tty_receive_parity_error(struct tty_struct *tty,
 static inline void n_tty_receive_char(struct tty_struct *tty, unsigned char c)
 {
         unsigned long flags;
+        int parmrk;
 
         if (tty->raw) {
                 put_tty_queue(c, tty);
@@ -1144,21 +1145,24 @@ static inline void n_tty_receive_char(struct tty_struct *tty, unsigned char c)
          */
         if (!test_bit(c, tty->process_char_map) || tty->lnext) {
                 tty->lnext = 0;
-                if (L_ECHO(tty)) {
-                        finish_erasing(tty);
-                        if (tty->read_cnt >= N_TTY_BUF_SIZE-1) {
-                                /* beep if no space */
+                parmrk = (c == (unsigned char) '\377' && I_PARMRK(tty)) ? 1 : 0;
+                if (tty->read_cnt >= (N_TTY_BUF_SIZE - parmrk - 1)) {
+                        /* beep if no space */
+                        if (L_ECHO(tty)) {
                                 echo_char_raw('\a', tty);
                                 process_echoes(tty);
-                                return;
                         }
+                        return;
+                }
+                if (L_ECHO(tty)) {
+                        finish_erasing(tty);
                         /* Record the column of first canon char. */
                         if (tty->canon_head == tty->read_head)
                                 echo_set_canon_col(tty);
                         echo_char(c, tty);
                         process_echoes(tty);
                 }
-                if (I_PARMRK(tty) && c == (unsigned char) '\377')
+                if (parmrk)
                         put_tty_queue(c, tty);
                 put_tty_queue(c, tty);
                 return;
@@ -1250,15 +1254,22 @@ send_signal:
                         return;
                 }
                 if (c == '\n') {
-                        if (L_ECHO(tty) || L_ECHONL(tty)) {
-                                if (tty->read_cnt >= N_TTY_BUF_SIZE-1)
+                        if (tty->read_cnt >= N_TTY_BUF_SIZE) {
+                                if (L_ECHO(tty)) {
                                         echo_char_raw('\a', tty);
+                                        process_echoes(tty);
+                                }
+                                return;
+                        }
+                        if (L_ECHO(tty) || L_ECHONL(tty)) {
                                 echo_char_raw('\n', tty);
                                 process_echoes(tty);
                         }
                         goto handle_newline;
                 }
                 if (c == EOF_CHAR(tty)) {
+                        if (tty->read_cnt >= N_TTY_BUF_SIZE)
+                                return;
                         if (tty->canon_head != tty->read_head)
                                 set_bit(TTY_PUSH, &tty->flags);
                         c = __DISABLED_CHAR;
@@ -1266,12 +1277,19 @@ send_signal:
                 }
                 if ((c == EOL_CHAR(tty)) ||
                     (c == EOL2_CHAR(tty) && L_IEXTEN(tty))) {
+                        parmrk = (c == (unsigned char) '\377' && I_PARMRK(tty))
+                                 ? 1 : 0;
+                        if (tty->read_cnt >= (N_TTY_BUF_SIZE - parmrk)) {
+                                if (L_ECHO(tty)) {
+                                        echo_char_raw('\a', tty);
+                                        process_echoes(tty);
+                                }
+                                return;
+                        }
                         /*
                          * XXX are EOL_CHAR and EOL2_CHAR echoed?!?
                          */
                         if (L_ECHO(tty)) {
-                                if (tty->read_cnt >= N_TTY_BUF_SIZE-1)
-                                        echo_char_raw('\a', tty);
                                 /* Record the column of first canon char. */
                                 if (tty->canon_head == tty->read_head)
                                         echo_set_canon_col(tty);
@@ -1282,7 +1300,7 @@ send_signal:
                          * XXX does PARMRK doubling happen for
                          * EOL_CHAR and EOL2_CHAR?
                          */
-                        if (I_PARMRK(tty) && c == (unsigned char) '\377')
+                        if (parmrk)
                                 put_tty_queue(c, tty);
 
 handle_newline:
@@ -1299,14 +1317,17 @@ handle_newline:
                 }
         }
 
-        if (L_ECHO(tty)) {
-                finish_erasing(tty);
-                if (tty->read_cnt >= N_TTY_BUF_SIZE-1) {
-                        /* beep if no space */
+        parmrk = (c == (unsigned char) '\377' && I_PARMRK(tty)) ? 1 : 0;
+        if (tty->read_cnt >= (N_TTY_BUF_SIZE - parmrk - 1)) {
+                /* beep if no space */
+                if (L_ECHO(tty)) {
                         echo_char_raw('\a', tty);
                         process_echoes(tty);
-                        return;
                 }
+                return;
+        }
+        if (L_ECHO(tty)) {
+                finish_erasing(tty);
                 if (c == '\n')
                         echo_char_raw('\n', tty);
                 else {
@@ -1318,7 +1339,7 @@ handle_newline:
                 process_echoes(tty);
         }
 
-        if (I_PARMRK(tty) && c == (unsigned char) '\377')
+        if (parmrk)
                 put_tty_queue(c, tty);
 
         put_tty_queue(c, tty);