linux-kernel - [PATCH 5.19 056/365] NFSv4/pnfs: Fix a use-after-free bug in open

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: <20220823080120.521722033@linuxfoundation.org>
Date:   Tue, 23 Aug 2022 09:59:17 +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,
        Trond Myklebust <trond.myklebust@...merspace.com>
Subject: [PATCH 5.19 056/365] NFSv4/pnfs: Fix a use-after-free bug in open

From: Trond Myklebust <trond.myklebust@...merspace.com>

commit 2135e5d56278ffdb1c2e6d325dc6b87f669b9dac upstream.

If someone cancels the open RPC call, then we must not try to free
either the open slot or the layoutget operation arguments, since they
are likely still in use by the hung RPC call.

Fixes: 6949493884fe ("NFSv4: Don't hold the layoutget locks across multiple RPC calls")
Signed-off-by: Trond Myklebust <trond.myklebust@...merspace.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
---
 fs/nfs/nfs4proc.c |   11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)

--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -3096,12 +3096,13 @@ static int _nfs4_open_and_get_state(stru
 	}
 
 out:
-	if (opendata->lgp) {
-		nfs4_lgopen_release(opendata->lgp);
-		opendata->lgp = NULL;
-	}
-	if (!opendata->cancelled)
+	if (!opendata->cancelled) {
+		if (opendata->lgp) {
+			nfs4_lgopen_release(opendata->lgp);
+			opendata->lgp = NULL;
+		}
 		nfs4_sequence_free_slot(&opendata->o_res.seq_res);
+	}
 	return ret;
 }