From nobody Sun Dec 14 12:14:51 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 1764754691690777.1113134642612; Wed, 3 Dec 2025 01:38:11 -0800 (PST) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1vQjHh-0000HG-0t; Wed, 03 Dec 2025 04:36:29 -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 1vQjHf-0000FO-MH; Wed, 03 Dec 2025 04:36:27 -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 1vQjHd-00074X-Vh; Wed, 03 Dec 2025 04:36:27 -0500 Received: from tsrv.corpit.ru (tsrv.tls.msk.ru [192.168.177.2]) by isrv.corpit.ru (Postfix) with ESMTP id 82BC91708B1; Wed, 03 Dec 2025 12:35:54 +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 6F0BD32B5A8; Wed, 03 Dec 2025 12:36:12 +0300 (MSK) From: Michael Tokarev To: qemu-devel@nongnu.org Cc: qemu-stable@nongnu.org, Peter Maydell , =?UTF-8?q?Philippe=20Mathieu-Daud=C3=A9?= , Michael Tokarev Subject: [Stable-10.1.3 82/96] hw/display/exynos4210_fimd: Account for zero length in fimd_update_memory_section() Date: Wed, 3 Dec 2025 12:35:15 +0300 Message-ID: <20251203093612.2370716-6-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: 1764754692208019200 From: Peter Maydell In fimd_update_memory_section() we attempt ot find and map part of the RAM MR which backs the framebuffer, based on guest-configurable size and start address. If the guest configures framebuffer settings which result in a zero-sized framebuffer, we hit an assertion(), because memory_region_find() will return a NULL mem_section.mr. Explicitly check for the zero-size case and treat this as a guest error. Because we now have a code path which can reach error_return without calling memory_region_find to set w->mem_section, we must NULL out w->mem_section.mr after the unref of the old MR, so that error_return does not incorrectly double-unref the old MR. Cc: qemu-stable@nongnu.org Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1407 Signed-off-by: Peter Maydell Reviewed-by: Philippe Mathieu-Daud=C3=A9 Message-id: 20251107143913.1341358-1-peter.maydell@linaro.org (cherry picked from commit 579be921f509fb9d2deccc4233496e36b221abb3) Signed-off-by: Michael Tokarev diff --git a/hw/display/exynos4210_fimd.c b/hw/display/exynos4210_fimd.c index c61e0280a7..eec874d0b1 100644 --- a/hw/display/exynos4210_fimd.c +++ b/hw/display/exynos4210_fimd.c @@ -1147,6 +1147,13 @@ static void fimd_update_memory_section(Exynos4210fim= dState *s, unsigned win) if (w->mem_section.mr) { memory_region_set_log(w->mem_section.mr, false, DIRTY_MEMORY_VGA); memory_region_unref(w->mem_section.mr); + w->mem_section.mr =3D NULL; + } + + if (w->fb_len =3D=3D 0) { + qemu_log_mask(LOG_GUEST_ERROR, + "FIMD: Guest config means framebuffer is zero length= \n"); + goto error_return; } =20 w->mem_section =3D memory_region_find(s->fbmem, fb_start_addr, w->fb_l= en); --=20 2.47.3