From: Jiri Slaby <jslaby@suse.cz>
To: gregkh@linuxfoundation.org
Cc: alan@linux.intel.com, linux-kernel@vger.kernel.org, jirislaby@gmail.com
Subject: [PATCH 09/21] TTY: n_tty, simplify read_buf+echo_buf allocation
Date: Thu, 18 Oct 2012 22:26:35 +0200 [thread overview]
Message-ID: <1350592007-9216-10-git-send-email-jslaby@suse.cz> (raw)
In-Reply-To: <1350592007-9216-1-git-send-email-jslaby@suse.cz>
ldisc->open and close are called only once and cannot cross. So the
tests in open and close are superfluous. Remove them. (But leave sets
to NULL to ensure there is not a bug somewhere.)
And when the tests are gone, handle properly failures in open. We
leaked read_buf if allocation of echo_buf failed before. Now this is
not the case anymore.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
---
drivers/tty/n_tty.c | 31 +++++++++++++------------------
1 file changed, 13 insertions(+), 18 deletions(-)
diff --git a/drivers/tty/n_tty.c b/drivers/tty/n_tty.c
index 8c0b7b4..f27289d 100644
--- a/drivers/tty/n_tty.c
+++ b/drivers/tty/n_tty.c
@@ -1561,14 +1561,10 @@ static void n_tty_set_termios(struct tty_struct *tty, struct ktermios *old)
static void n_tty_close(struct tty_struct *tty)
{
n_tty_flush_buffer(tty);
- if (tty->read_buf) {
- kfree(tty->read_buf);
- tty->read_buf = NULL;
- }
- if (tty->echo_buf) {
- kfree(tty->echo_buf);
- tty->echo_buf = NULL;
- }
+ kfree(tty->read_buf);
+ kfree(tty->echo_buf);
+ tty->read_buf = NULL;
+ tty->echo_buf = NULL;
}
/**
@@ -1587,17 +1583,11 @@ static int n_tty_open(struct tty_struct *tty)
return -EINVAL;
/* These are ugly. Currently a malloc failure here can panic */
- if (!tty->read_buf) {
- tty->read_buf = kzalloc(N_TTY_BUF_SIZE, GFP_KERNEL);
- if (!tty->read_buf)
- return -ENOMEM;
- }
- if (!tty->echo_buf) {
- tty->echo_buf = kzalloc(N_TTY_BUF_SIZE, GFP_KERNEL);
+ tty->read_buf = kzalloc(N_TTY_BUF_SIZE, GFP_KERNEL);
+ tty->echo_buf = kzalloc(N_TTY_BUF_SIZE, GFP_KERNEL);
+ if (!tty->read_buf || !tty->echo_buf)
+ goto err_free_bufs;
- if (!tty->echo_buf)
- return -ENOMEM;
- }
reset_buffer_flags(tty);
tty_unthrottle(tty);
tty->column = 0;
@@ -1605,6 +1595,11 @@ static int n_tty_open(struct tty_struct *tty)
tty->minimum_to_wake = 1;
tty->closing = 0;
return 0;
+err_free_bufs:
+ kfree(tty->read_buf);
+ kfree(tty->echo_buf);
+
+ return -ENOMEM;
}
static inline int input_available_p(struct tty_struct *tty, int amt)
--
1.7.12.3
next prev parent reply other threads:[~2012-10-18 20:27 UTC|newest]
Thread overview: 47+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-10-18 20:26 [PATCH 00/21] TTY buffer in tty_port and other stuff Jiri Slaby
2012-10-18 20:26 ` [PATCH 01/21] TTY: devpts, don't care about TTY in devpts_get_tty Jiri Slaby
2012-10-18 20:26 ` [PATCH 02/21] TTY: devpts, return created inode from devpts_pty_new Jiri Slaby
2012-10-18 20:26 ` [PATCH 03/21] TTY: devpts, do not set driver_data Jiri Slaby
2012-10-18 20:26 ` [PATCH 04/21] TTY: devpts, document devpts inode operations Jiri Slaby
2012-10-18 20:26 ` [PATCH 05/21] TTY: move devpts kill to pty Jiri Slaby
2012-10-18 20:26 ` [PATCH 06/21] TTY: vt, fix paste_selection ldisc handling Jiri Slaby
2012-10-18 20:26 ` [PATCH 07/21] TTY: ldisc, wait for idle ldisc in release Jiri Slaby
2012-10-18 20:26 ` [PATCH 08/21] TTY: hci_ldisc, remove invalid check in open Jiri Slaby
2012-10-18 20:47 ` Marcel Holtmann
2012-10-18 20:26 ` Jiri Slaby [this message]
2012-10-18 20:26 ` [PATCH 10/21] TTY: n_tty, remove bogus checks Jiri Slaby
2012-10-18 20:26 ` [PATCH 11/21] TTY: audit, stop accessing tty->icount Jiri Slaby
2012-10-18 20:26 ` [PATCH 12/21] TTY: n_tty, add ldisc data to n_tty Jiri Slaby
2012-10-18 20:26 ` [PATCH 13/21] TTY: move ldisc data from tty_struct: simple members Jiri Slaby
2012-10-18 20:26 ` [PATCH 14/21] TTY: move ldisc data from tty_struct: bitmaps Jiri Slaby
2012-10-18 20:26 ` [PATCH 15/21] TTY: move ldisc data from tty_struct: read_* and echo_* and canon_* stuff Jiri Slaby
2012-10-18 20:26 ` [PATCH 16/21] TTY: move ldisc data from tty_struct: locks Jiri Slaby
2012-10-18 20:26 ` [PATCH 17/21] TTY: n_tty, propagate n_tty_data Jiri Slaby
2012-10-18 20:26 ` [PATCH 18/21] TTY: move TTY_FLUSH* flags to tty_port Jiri Slaby
2012-10-18 20:26 ` [PATCH 19/21] TTY: tty_buffer, cache pointer to tty->buf Jiri Slaby
2012-10-18 20:26 ` [PATCH 20/21] TTY: add port -> tty link Jiri Slaby
2012-10-18 20:26 ` [PATCH 21/21] TTY: move tty buffers to tty_port Jiri Slaby
2012-10-25 18:02 ` Sasha Levin
2012-10-25 18:08 ` Greg KH
2012-10-31 12:53 ` Jiri Slaby
2012-10-31 15:30 ` Sasha Levin
2012-10-31 15:32 ` Jiri Slaby
2012-10-31 15:59 ` Sasha Levin
2012-11-02 15:51 ` Jiri Slaby
2012-11-02 16:07 ` Sasha Levin
2012-11-02 16:18 ` Jiri Slaby
2012-11-02 16:23 ` Sasha Levin
2012-11-03 2:03 ` Sasha Levin
2012-11-03 15:55 ` Jiri Slaby
2012-11-03 23:06 ` Sasha Levin
2012-11-04 0:53 ` Sasha Levin
2012-11-27 19:57 ` Peter Hurley
2012-11-30 23:52 ` Sasha Levin
2012-12-01 14:59 ` flush_to_ldisc accesses tty after free (was: [PATCH 21/21] TTY: move tty buffers to tty_port) Peter Hurley
2012-12-01 20:06 ` Peter Hurley
2012-12-02 19:57 ` Peter Hurley
2012-12-04 19:21 ` Ilya Zykov
2012-10-31 20:10 ` [PATCH 21/21] TTY: move tty buffers to tty_port Sasha Levin
2012-10-18 21:12 ` [PATCH 00/21] TTY buffer in tty_port and other stuff Greg KH
2012-10-22 14:57 ` Alan Cox
2012-10-22 23:59 ` Greg KH
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