From: Shyam Prasad N <sprasad@microsoft.com>
Date: Mon, 19 Jul 2021 14:04:11 +0000 (+0000)
Subject: cifs: add WARN_ON for when chan_count goes below minimum
X-Git-Tag: v6.6.17~8378^2~8
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=2e0fa298d149e07005504350358066f380f72b52;p=platform%2Fkernel%2Flinux-rpi.git

cifs: add WARN_ON for when chan_count goes below minimum

chan_count keeps track of the total number of channels.
Since at least the primary channel will always be connected,
this value can never go below 1. Warn if that happens.

Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
---

diff --git a/fs/cifs/sess.c b/fs/cifs/sess.c
index b121a25..61fc8cb 100644
--- a/fs/cifs/sess.c
+++ b/fs/cifs/sess.c
@@ -347,6 +347,11 @@ out:
 		/* we rely on all bits beyond chan_count to be clear */
 		cifs_chan_clear_need_reconnect(ses, chan->server);
 		ses->chan_count--;
+		/*
+		 * chan_count should never reach 0 as at least the primary
+		 * channel is always allocated
+		 */
+		WARN_ON(ses->chan_count < 1);
 		spin_unlock(&ses->chan_lock);
 	}