linux-kernel - [PATCH 4.19 30/42] net: dsa: mv88e6xxx: Fix clearing of stats counters

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 for Android: free password hash cracker in your pocket

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

Message-Id: <20181121183149.288064693@linuxfoundation.org>
Date:   Wed, 21 Nov 2018 20:06:06 +0100
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org, Chris Healy <Chris.Healy@....aero>,
        Andrew Lunn <andrew@...n.ch>,
        "David S. Miller" <davem@...emloft.net>
Subject: [PATCH 4.19 30/42] net: dsa: mv88e6xxx: Fix clearing of stats counters

4.19-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Andrew Lunn <andrew@...n.ch>

[ Upstream commit a9049ff9214da68df1179a7d5e36b43479abc9b8 ]

The mv88e6161 would sometime fail to probe with a timeout waiting for
the switch to complete an operation. This operation is supposed to
clear the statistics counters. However, due to a read/modify/write,
without the needed mask, the operation actually carried out was more
random, with invalid parameters, resulting in the switch not
responding. We need to preserve the histogram mode bits, so apply a
mask to keep them.

Reported-by: Chris Healy <Chris.Healy@....aero>
Fixes: 40cff8fca9e3 ("net: dsa: mv88e6xxx: Fix stats histogram mode")
Signed-off-by: Andrew Lunn <andrew@...n.ch>
Signed-off-by: David S. Miller <davem@...emloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
---
 drivers/net/dsa/mv88e6xxx/global1.c |    2 ++
 1 file changed, 2 insertions(+)

--- a/drivers/net/dsa/mv88e6xxx/global1.c
+++ b/drivers/net/dsa/mv88e6xxx/global1.c
@@ -567,6 +567,8 @@ int mv88e6xxx_g1_stats_clear(struct mv88
 	if (err)
 		return err;
 
+	/* Keep the histogram mode bits */
+	val &= MV88E6XXX_G1_STATS_OP_HIST_RX_TX;
 	val |= MV88E6XXX_G1_STATS_OP_BUSY | MV88E6XXX_G1_STATS_OP_FLUSH_ALL;
 
 	err = mv88e6xxx_g1_write(chip, MV88E6XXX_G1_STATS_OP, val);