From: Shyam Prasad N <sprasad@microsoft.com>
Date: Thu, 22 Dec 2022 12:54:44 +0000 (+0000)
Subject: cifs: fix interface count calculation during refresh
X-Git-Tag: v6.0.19~146
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=a3d8cdde0d7c57ec5df1b8b3445d7d6e26511d4e;p=thirdparty%2Fkernel%2Fstable.git

cifs: fix interface count calculation during refresh

commit cc7d79d4fad6a4eab3f88c4bb237de72be4478f1 upstream.

The last fix to iface_count did fix the overcounting issue.
However, during each refresh, we could end up undercounting
the iface_count, if a match was found.

Fixing this by doing increments and decrements instead of
setting it to 0 before each parsing of server interfaces.

Fixes: 096bbeec7bd6 ("smb3: interface count displayed incorrectly")
Cc: stable@vger.kernel.org # 6.1
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c
index 74052b51655ec..05c9c75360fab 100644
--- a/fs/cifs/smb2ops.c
+++ b/fs/cifs/smb2ops.c
@@ -530,7 +530,6 @@ parse_server_interfaces(struct network_interface_info_ioctl_rsp *buf,
 	p = buf;
 
 	spin_lock(&ses->iface_lock);
-	ses->iface_count = 0;
 	/*
 	 * Go through iface_list and do kref_put to remove
 	 * any unused ifaces. ifaces in use will be removed
@@ -540,6 +539,7 @@ parse_server_interfaces(struct network_interface_info_ioctl_rsp *buf,
 				 iface_head) {
 		iface->is_active = 0;
 		kref_put(&iface->refcount, release_iface);
+		ses->iface_count--;
 	}
 	spin_unlock(&ses->iface_lock);
 
@@ -617,6 +617,7 @@ parse_server_interfaces(struct network_interface_info_ioctl_rsp *buf,
 				/* just get a ref so that it doesn't get picked/freed */
 				iface->is_active = 1;
 				kref_get(&iface->refcount);
+				ses->iface_count++;
 				spin_unlock(&ses->iface_lock);
 				goto next_iface;
 			} else if (ret < 0) {