linux-kernel - [PATCH 4.9 12/63] cxl: Fix wrong comparison in cxl_adapter_context

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: <20180907211013.672350762@linuxfoundation.org>
Date:   Fri,  7 Sep 2018 23:09:43 +0200
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org, Dan Carpenter <dan.carpenter@...cle.com>,
        Vaibhav Jain <vaibhav@...ux.ibm.com>,
        Andrew Donnellan <andrew.donnellan@....ibm.com>,
        Frederic Barrat <fbarrat@...ux.vnet.ibm.com>,
        Michael Ellerman <mpe@...erman.id.au>
Subject: [PATCH 4.9 12/63] cxl: Fix wrong comparison in cxl_adapter_context_get()

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

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

From: Vaibhav Jain <vaibhav@...ux.ibm.com>

commit ef6cb5f1a048fdf91ccee6d63d2bfa293338502d upstream.

Function atomic_inc_unless_negative() returns a bool to indicate
success/failure. However cxl_adapter_context_get() wrongly compares
the return value against '>=0' which will always be true. The patch
fixes this comparison to '==0' there by also fixing this compile time
warning:

	drivers/misc/cxl/main.c:290 cxl_adapter_context_get()
	warn: 'atomic_inc_unless_negative(&adapter->contexts_num)' is unsigned

Fixes: 70b565bbdb91 ("cxl: Prevent adapter reset if an active context exists")
Cc: stable@...r.kernel.org # v4.9+
Reported-by: Dan Carpenter <dan.carpenter@...cle.com>
Signed-off-by: Vaibhav Jain <vaibhav@...ux.ibm.com>
Acked-by: Andrew Donnellan <andrew.donnellan@....ibm.com>
Acked-by: Frederic Barrat <fbarrat@...ux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@...erman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>

---
 drivers/misc/cxl/main.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/misc/cxl/main.c
+++ b/drivers/misc/cxl/main.c
@@ -293,7 +293,7 @@ int cxl_adapter_context_get(struct cxl *
 	int rc;
 
 	rc = atomic_inc_unless_negative(&adapter->contexts_num);
-	return rc >= 0 ? 0 : -EBUSY;
+	return rc ? 0 : -EBUSY;
 }
 
 void cxl_adapter_context_put(struct cxl *adapter)