linux-kernel - [PATCH 13/19] mxser: clean up timeout handling in mxser_wait_until

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20211118073125.12283-14-jslaby@suse.cz>
Date:   Thu, 18 Nov 2021 08:31:19 +0100
From:   Jiri Slaby <jslaby@...e.cz>
To:     gregkh@...uxfoundation.org
Cc:     linux-serial@...r.kernel.org, linux-kernel@...r.kernel.org,
        Jiri Slaby <jslaby@...e.cz>
Subject: [PATCH 13/19] mxser: clean up timeout handling in mxser_wait_until_sent()

timeout cannot be zero at the point of use. So no need to check for
zero. Also precompute the expiration time (into expire) and use it. This
makes the code more clear.

Signed-off-by: Jiri Slaby <jslaby@...e.cz>
---
 drivers/tty/mxser.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/tty/mxser.c b/drivers/tty/mxser.c
index b3ae3b105af0..c3f262dc936d 100644
--- a/drivers/tty/mxser.c
+++ b/drivers/tty/mxser.c
@@ -1420,7 +1420,7 @@ static bool mxser_tx_empty(struct mxser_port *info)
 static void mxser_wait_until_sent(struct tty_struct *tty, int timeout)
 {
 	struct mxser_port *info = tty->driver_data;
-	unsigned long orig_jiffies, char_time;
+	unsigned long expire, char_time;
 
 	if (info->type == PORT_UNKNOWN)
 		return;
@@ -1428,7 +1428,6 @@ static void mxser_wait_until_sent(struct tty_struct *tty, int timeout)
 	if (info->xmit_fifo_size == 0)
 		return;		/* Just in case.... */
 
-	orig_jiffies = jiffies;
 	/*
 	 * Set the check interval to be 1/5 of the estimated time to
 	 * send a single character, and make it at least 1.  The check
@@ -1458,11 +1457,13 @@ static void mxser_wait_until_sent(struct tty_struct *tty, int timeout)
 	if (!timeout || timeout > 2 * info->timeout)
 		timeout = 2 * info->timeout;
 
+	expire = jiffies + timeout;
+
 	while (mxser_tx_empty(info)) {
 		msleep_interruptible(char_time);
 		if (signal_pending(current))
 			break;
-		if (timeout && time_after(jiffies, orig_jiffies + timeout))
+		if (time_after(jiffies, expire))
 			break;
 	}
 }
-- 
2.33.1