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 EC29AC83F25 for ; Tue, 22 Jul 2025 10:16:47 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1ueA2U-00019c-Na; Tue, 22 Jul 2025 06:16:02 -0400 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 1ueA2S-00017P-52 for qemu-devel@nongnu.org; Tue, 22 Jul 2025 06:16:00 -0400 Received: from air.basealt.ru ([193.43.8.18]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1ueA2M-00087G-Or for qemu-devel@nongnu.org; Tue, 22 Jul 2025 06:15:59 -0400 Received: from boringlust.malta.altlinux.ru (obninsk.basealt.ru [217.15.195.17]) (Authenticated sender: rastyoginds) by air.basealt.ru (Postfix) with ESMTPSA id C68C52339B; Tue, 22 Jul 2025 13:15:47 +0300 (MSK) From: gerben@altlinux.org To: qemu-devel@nongnu.org, laurent@vivier.eu Cc: sdl.qemu@linuxtesting.org Subject: [PATCH] linux-user: check for NULL before using interval_tree_iter_first result Date: Tue, 22 Jul 2025 13:15:05 +0300 Message-ID: <20250722101544.16366-1-gerben@altlinux.org> X-Mailer: git-send-email 2.42.2 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Received-SPF: pass client-ip=193.43.8.18; envelope-from=gerben@altlinux.org; helo=air.basealt.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_RPBL_BLOCKED=0.001, RCVD_IN_VALIDITY_SAFE_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+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org From: Denis Rastyogin interval_tree_iter_first() may return NULL if the interval tree is empty or invalid. Add a check for NULL before dereferencing the pointer to avoid potential crashes due to null pointer dereference in open_self_maps_2(). Found by Linux Verification Center (linuxtesting.org) with SVACE. Signed-off-by: Denis Rastyogin --- linux-user/syscall.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/linux-user/syscall.c b/linux-user/syscall.c index 91360a072c..d5d5912c96 100644 --- a/linux-user/syscall.c +++ b/linux-user/syscall.c @@ -8172,6 +8172,9 @@ static int open_self_maps_2(void *opaque, vaddr guest_start, while (1) { IntervalTreeNode *n = interval_tree_iter_first(d->host_maps, host_start, host_start); + if (n == NULL) { + return -1; + } MapInfo *mi = container_of(n, MapInfo, itree); uintptr_t this_hlast = MIN(host_last, n->last); target_ulong this_gend = h2g(this_hlast) + 1; -- 2.42.2