From patchwork Fri Nov 24 11:30:38 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dmitry Frolov X-Patchwork-Id: 13467576 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 43685C61D97 for ; Fri, 24 Nov 2023 11:33:09 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1r6UQ2-0003Jc-Ue; Fri, 24 Nov 2023 06:32:22 -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 1r6UPz-0003Fu-Tf; Fri, 24 Nov 2023 06:32:19 -0500 Received: from mx.swemel.ru ([95.143.211.150]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1r6UPx-0006s5-NO; Fri, 24 Nov 2023 06:32:19 -0500 From: Dmitry Frolov DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=swemel.ru; s=mail; t=1700825530; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=Pu9NU45BXErFOacHk+M+S/D8MM3PFGCAXvanrcLKpYk=; b=LvH55AComKV6WKCFb3sazJrpwq4HgBk6hmB7tpsghIlJKtcYxMGHOWnKbSck8swLFXatLS yzoLZPkV7Vl+5duDLivC5KpXXfKyG7Q3EQio0RPvsM3aA0AmuWDXlfOkdPaIOvWJ/l7eH1 0uc7KbFhN/xmbGF4Riu7DiMY57Nt+d0= To: kwolf@redhat.com, hreitz@redhat.com, qemu-block@nongnu.org Cc: sdl.qemu@linuxtesting.org, qemu-devel@nongnu.org, Dmitry Frolov Subject: [PATCH] block/monitor: blk_bs() return value check Date: Fri, 24 Nov 2023 14:30:38 +0300 Message-Id: <20231124113037.2477645-1-frolov@swemel.ru> MIME-Version: 1.0 Received-SPF: pass client-ip=95.143.211.150; envelope-from=frolov@swemel.ru; helo=mx.swemel.ru 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, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 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 blk_bs() may return NULL, which will be dereferenced without a check in bdrv_commit(). Found by Linux Verification Center (linuxtesting.org) with SVACE. Signed-off-by: Dmitry Frolov --- block/monitor/block-hmp-cmds.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/block/monitor/block-hmp-cmds.c b/block/monitor/block-hmp-cmds.c index c729cbf1eb..ade627bc27 100644 --- a/block/monitor/block-hmp-cmds.c +++ b/block/monitor/block-hmp-cmds.c @@ -221,7 +221,13 @@ void hmp_commit(Monitor *mon, const QDict *qdict) return; } - bs = bdrv_skip_implicit_filters(blk_bs(blk)); + bs = blk_bs(blk); + if (!bs) { + error_report("Device '%s' is invalid", device); + return; + } + + bs = bdrv_skip_implicit_filters(bs); aio_context = bdrv_get_aio_context(bs); aio_context_acquire(aio_context);