From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 9B6DD360BC for ; Thu, 21 Dec 2023 15:09:38 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="MyDQAklb" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1703171377; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=3Le+gA8/eXxjZEgbRfZ5PEeY/UYos/EZllx1bsLSYMw=; b=MyDQAklbQdgvuu5GlVku2nXjN7d5EE42pN8Fy0QAoEKM8CQrAc8AWK18CNo4pHJrKeayal 4uF68yPnlEHJyowRuSrFL3btkdTiU27bFPAgTpNj+ct5xi+YZZx/89WLXbxaX1LofK2jzv DQPHF61CzbS9RWY3HT+DIAb52YkFPSk= Received: from mimecast-mx02.redhat.com (mx-ext.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-394-cLcz9jdNOGCqSLHoOXu-xQ-1; Thu, 21 Dec 2023 10:09:33 -0500 X-MC-Unique: cLcz9jdNOGCqSLHoOXu-xQ-1 Received: from smtp.corp.redhat.com (int-mx09.intmail.prod.int.rdu2.redhat.com [10.11.54.9]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 4E5643813BD2; Thu, 21 Dec 2023 15:09:33 +0000 (UTC) Received: from warthog.procyon.org.uk (unknown [10.39.195.169]) by smtp.corp.redhat.com (Postfix) with ESMTP id E34D7492BC6; Thu, 21 Dec 2023 15:09:31 +0000 (UTC) Organization: Red Hat UK Ltd. Registered Address: Red Hat UK Ltd, Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SI4 1TE, United Kingdom. Registered in England and Wales under Company Registration No. 3798903 From: David Howells To: torvalds@linux-foundation.org cc: Anastasia Belova , Marc Dionne , dhowells@redhat.com, linux-afs@lists.infradead.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, lvc-project@linuxtesting.org Subject: [PATCH] afs: Fix overwriting of result of DNS query Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-ID: <1842327.1703171371.1@warthog.procyon.org.uk> Content-Transfer-Encoding: quoted-printable Date: Thu, 21 Dec 2023 15:09:31 +0000 Message-ID: <1842328.1703171371@warthog.procyon.org.uk> X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.9 Hi Linus, Could you apply this fix, please? Thanks, David --- In afs_update_cell(), ret is the result of the DNS lookup and the errors are to be handled by a switch - however, the value gets clobbered in between by setting it to -ENOMEM in case afs_alloc_vlserver_list() fails. Fix this by moving the setting of -ENOMEM into the error handling for OOM failure. Further, only do it if we don't have an alternative error to return. Found by Linux Verification Center (linuxtesting.org) with SVACE. Based o= n a patch from Anastasia Belova[1]. Fixes: d5c32c89b208 ("afs: Fix cell DNS lookup") Signed-off-by: David Howells Reviewed-by: Jeffrey Altman cc: Anastasia Belova cc: Marc Dionne cc: linux-afs@lists.infradead.org cc: lvc-project@linuxtesting.org Link: https://lore.kernel.org/r/20231221085849.1463-1-abelova@astralinux.r= u/ [1] Link: https://lore.kernel.org/r/1700862.1703168632@warthog.procyon.org.uk/= # v1 --- fs/afs/cell.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/fs/afs/cell.c b/fs/afs/cell.c index 988c2ac7cece..926cb1188eba 100644 --- a/fs/afs/cell.c +++ b/fs/afs/cell.c @@ -409,10 +409,12 @@ static int afs_update_cell(struct afs_cell *cell) if (ret =3D=3D -ENOMEM) goto out_wake; = - ret =3D -ENOMEM; vllist =3D afs_alloc_vlserver_list(0); - if (!vllist) + if (!vllist) { + if (ret >=3D 0) + ret =3D -ENOMEM; goto out_wake; + } = switch (ret) { case -ENODATA: