From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 648CDCFD2F6 for ; Tue, 2 Dec 2025 08:32:59 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1vQLo3-0000rb-Sx; Tue, 02 Dec 2025 03:32:20 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1vQLo1-0000qd-BD for qemu-devel@nongnu.org; Tue, 02 Dec 2025 03:32:17 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1vQLny-0007In-GT for qemu-devel@nongnu.org; Tue, 02 Dec 2025 03:32:17 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1764664331; 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: in-reply-to:in-reply-to:references:references; bh=PlqrRvm9IwaVz0zr9mAiY+yA/lgInqpEN8yalyL4j4c=; b=ciw6uoEdptL4Pmmspep5ZLPxRETqAJZUyyBeV0H3nOJzjlQw2JIA0ixkgJ18ntNzyKWz3I CTyVug7bOiVWl7s2HKSmxTTtfF2meek1xpOpJz3rMAXfbBP/rfRfxL2tgnHC+h/8agVUr0 kQMtFKwwCfPkC2MgvmEFVZVI1MQEneg= Received: from mx-prod-mc-03.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-544-c5x7YLivPKGl1z6bV9bhcQ-1; Tue, 02 Dec 2025 03:32:10 -0500 X-MC-Unique: c5x7YLivPKGl1z6bV9bhcQ-1 X-Mimecast-MFC-AGG-ID: c5x7YLivPKGl1z6bV9bhcQ_1764664329 Received: from mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.93]) (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 mx-prod-mc-03.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id AB9CF1955E74; Tue, 2 Dec 2025 08:32:09 +0000 (UTC) Received: from blackfin.pond.sub.org (unknown [10.45.242.7]) by mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 4B3DD18002AC; Tue, 2 Dec 2025 08:32:09 +0000 (UTC) Received: by blackfin.pond.sub.org (Postfix, from userid 1000) id C4CB221E6741; Tue, 02 Dec 2025 09:32:06 +0100 (CET) From: Markus Armbruster To: qemu-devel@nongnu.org Cc: richard.henderson@linaro.org Subject: [PULL 2/2] kvm: Fix kvm_vm_ioctl() and kvm_device_ioctl() return value Date: Tue, 2 Dec 2025 09:32:06 +0100 Message-ID: <20251202083206.4180561-3-armbru@redhat.com> In-Reply-To: <20251202083206.4180561-1-armbru@redhat.com> References: <20251202083206.4180561-1-armbru@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.93 Received-SPF: pass client-ip=170.10.133.124; envelope-from=armbru@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H3=0.001, RCVD_IN_MSPIKE_WL=0.001, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, RCVD_IN_VALIDITY_SAFE_BLOCKED=0.001, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org These functions wrap ioctl(). When ioctl() fails, it sets @errno. The wrappers then return that @errno negated. Except they call accel_ioctl_end() between calling ioctl() and reading @errno. accel_ioctl_end() can clobber @errno, e.g. when a futex() system call fails. Seems unlikely, but it's a bug all the same. Fix by retrieving @errno before calling accel_ioctl_end(). Fixes: a27dd2de68f3 (KVM: keep track of running ioctls) Signed-off-by: Markus Armbruster Reviewed-by: Philippe Mathieu-Daudé Message-ID: <20251128152050.3417834-1-armbru@redhat.com> --- accel/kvm/kvm-all.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c index f9254ae654..28006d73c5 100644 --- a/accel/kvm/kvm-all.c +++ b/accel/kvm/kvm-all.c @@ -3373,10 +3373,10 @@ int kvm_vm_ioctl(KVMState *s, unsigned long type, ...) trace_kvm_vm_ioctl(type, arg); accel_ioctl_begin(); ret = ioctl(s->vmfd, type, arg); - accel_ioctl_end(); if (ret == -1) { ret = -errno; } + accel_ioctl_end(); return ret; } @@ -3413,10 +3413,10 @@ int kvm_device_ioctl(int fd, unsigned long type, ...) trace_kvm_device_ioctl(fd, type, arg); accel_ioctl_begin(); ret = ioctl(fd, type, arg); - accel_ioctl_end(); if (ret == -1) { ret = -errno; } + accel_ioctl_end(); return ret; } -- 2.49.0