From nobody Fri Apr 17 08:49:42 2026 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 400C8C43334 for ; Sat, 23 Jul 2022 08:00:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236019AbiGWIAN (ORCPT ); Sat, 23 Jul 2022 04:00:13 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35630 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232785AbiGWIAJ (ORCPT ); Sat, 23 Jul 2022 04:00:09 -0400 Received: from mail-pg1-x541.google.com (mail-pg1-x541.google.com [IPv6:2607:f8b0:4864:20::541]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8B6B41DF for ; Sat, 23 Jul 2022 01:00:06 -0700 (PDT) Received: by mail-pg1-x541.google.com with SMTP id bh13so6155922pgb.4 for ; Sat, 23 Jul 2022 01:00:06 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=+lfnDOjXhW7oeG1YfdtLm2gXojFDgdLapEjPNrm2eGM=; b=P+d5RjY4Kh2suZ/56c+y0VXrKklcrHEDMb74mAOWHVESlUV9kC1/+NnMJDrPi0kDrr iE4UITe/OxQnb8eRCcuSEl0YOPU5qxu93RdJD2PQW+l3gu/wTpLDE9UDh+2IA4RM4jAo lTKrtTxgOkfLS44KLNaNMGS2t9dVZhBdigo8TCgODn3/96rKJLG4wcwPL6HtGhlEZpqJ xyMbhQOG3V9mscZalmDhjely9aVDLWVoO7R0r06NS/NrrRqGYzvrSTpPR0nstKdkFMPg 3ArlREqd9fLo6bEvySQBWNDYD20Hts96q5OtrjQTM0qNyotZZdlGKrmIRdE3NwN4Ddpc Ae5Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=+lfnDOjXhW7oeG1YfdtLm2gXojFDgdLapEjPNrm2eGM=; b=TV59NIa9A/2j6oq4jQcZ3QJPwf6zBDMBiQOOpXPTbLO4RH9lhfGLm5zBPxDaSd/vy1 Mgju4Yu+cG7tDhjokqKMSa1czi4zJ0wbU1KBHeACbyJ1yY44MDLQ6h/VDYQ5b4H7ut8Z ljIep1BZDVXNcKAW1Z0fPAjCAOFx8uu/uZT01Mu7tgorh+XCROjSJGbfRQiTDOIMAUAs cB75F0V/F85u2Uva7+cea2XkSyGXgF1VRCJXI1bD7ptAg9YQ1yKYMj2OH/Hwe5ryOuKM Qgasdnu5AdPft74VuX1oPKIvg4s2stc0+3smju61aUWuB+8cuQBY2HzQ3uo+QTa8irMb 8p2g== X-Gm-Message-State: AJIora/HhtcbjkuifKtqwinWgWtGo5mo2YRVD4mS/e91IvwdLd0qwmUi 5R3NAMDZoJqvQ/8RvF9+dXk= X-Google-Smtp-Source: AGRyM1s1LPV6UAsJk1cWI9v18U6ylR2x3JT4IywPniYlyfHVl9UFa45nZNpShuvzDO3wWgVixEMRew== X-Received: by 2002:a65:6c05:0:b0:41a:d13f:f0fb with SMTP id y5-20020a656c05000000b0041ad13ff0fbmr1070388pgu.393.1658563205817; Sat, 23 Jul 2022 01:00:05 -0700 (PDT) Received: from localhost.localdomain ([223.79.193.31]) by smtp.gmail.com with ESMTPSA id a15-20020aa7970f000000b00525302fe9c4sm5245646pfg.190.2022.07.23.01.00.00 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 23 Jul 2022 01:00:05 -0700 (PDT) From: John Sanpe To: philipp.reisner@linbit.com, lars.ellenberg@linbit.com, christoph.boehmwalder@linbit.com Cc: drbd-dev@lists.linbit.com, linux-kernel@vger.kernel.org, John Sanpe Subject: [PATCH] lib/lru_cache: Fixed array overflow caused by incorrect boundary handling. Date: Sat, 23 Jul 2022 15:59:31 +0800 Message-Id: <20220723075931.163245-1-sanpeqf@gmail.com> X-Mailer: git-send-email 2.36.1 MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" This problem occurs when malloc element failed on the first time. At this time, the counter i is 0. When it's released, we subtract 1 in advance without checking, which will cause i to become UINT_MAX, resulting in array overflow. Signed-off-by: John Sanpe Reviewed-by: Christoph B=C3=B6hmwalder --- lib/lru_cache.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/lib/lru_cache.c b/lib/lru_cache.c index 52313acbfa62..04d95de92602 100644 --- a/lib/lru_cache.c +++ b/lib/lru_cache.c @@ -147,7 +147,7 @@ struct lru_cache *lc_create(const char *name, struct km= em_cache *cache, return lc; =20 /* else: could not allocate all elements, give up */ - for (i--; i; i--) { + while (i--) { void *p =3D element[i]; kmem_cache_free(cache, p - e_off); } --=20 2.36.1