From nobody Sun Dec 14 12:14:49 2025 Delivered-To: importer@patchew.org Authentication-Results: mx.zohomail.com; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1764754678927562.4291941490903; Wed, 3 Dec 2025 01:37:58 -0800 (PST) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1vQjJ1-0004LU-W7; Wed, 03 Dec 2025 04:37:52 -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 1vQjJ1-0004GA-09; Wed, 03 Dec 2025 04:37:51 -0500 Received: from isrv.corpit.ru ([212.248.84.144]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1vQjIz-0007BH-Cx; Wed, 03 Dec 2025 04:37:50 -0500 Received: from tsrv.corpit.ru (tsrv.tls.msk.ru [192.168.177.2]) by isrv.corpit.ru (Postfix) with ESMTP id AA4741708BF; Wed, 03 Dec 2025 12:35:55 +0300 (MSK) Received: from think4mjt.tls.msk.ru (mjtthink.wg.tls.msk.ru [192.168.177.146]) by tsrv.corpit.ru (Postfix) with ESMTP id 9619F32B5B6; Wed, 03 Dec 2025 12:36:13 +0300 (MSK) From: Michael Tokarev To: qemu-devel@nongnu.org Cc: qemu-stable@nongnu.org, Markus Armbruster , =?UTF-8?q?Philippe=20Mathieu-Daud=C3=A9?= , Michael Tokarev Subject: [Stable-10.1.3 96/96] kvm: Fix kvm_vm_ioctl() and kvm_device_ioctl() return value Date: Wed, 3 Dec 2025 12:35:29 +0300 Message-ID: <20251203093612.2370716-20-mjt@tls.msk.ru> X-Mailer: git-send-email 2.47.3 In-Reply-To: References: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Received-SPF: pass client-ip=212.248.84.144; envelope-from=mjt@tls.msk.ru; helo=isrv.corpit.ru X-Spam_score_int: -18 X-Spam_score: -1.9 X-Spam_bar: - X-Spam_report: (-1.9 / 5.0 requ) BAYES_00=-1.9, RCVD_IN_VALIDITY_CERTIFIED_BLOCKED=0.001, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, SPF_HELO_NONE=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+importer=patchew.org@nongnu.org Sender: qemu-devel-bounces+importer=patchew.org@nongnu.org X-ZM-MESSAGEID: 1764754680062019200 From: Markus Armbruster 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-Daud=C3=A9 Message-ID: <20251128152050.3417834-1-armbru@redhat.com> (cherry picked from commit 88be119fb19b8ee04d681ad9048cde9f6a37c631) Signed-off-by: Michael Tokarev diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c index 890d5ea9f8..8c360d8399 100644 --- a/accel/kvm/kvm-all.c +++ b/accel/kvm/kvm-all.c @@ -3381,10 +3381,10 @@ int kvm_vm_ioctl(KVMState *s, unsigned long type, .= ..) trace_kvm_vm_ioctl(type, arg); accel_ioctl_begin(); ret =3D ioctl(s->vmfd, type, arg); - accel_ioctl_end(); if (ret =3D=3D -1) { ret =3D -errno; } + accel_ioctl_end(); return ret; } =20 @@ -3421,10 +3421,10 @@ int kvm_device_ioctl(int fd, unsigned long type, ..= .) trace_kvm_device_ioctl(fd, type, arg); accel_ioctl_begin(); ret =3D ioctl(fd, type, arg); - accel_ioctl_end(); if (ret =3D=3D -1) { ret =3D -errno; } + accel_ioctl_end(); return ret; } =20 --=20 2.47.3