From nobody Sun Dec 14 19:31:42 2025 Received: from dggsgout11.his.huawei.com (dggsgout11.his.huawei.com [45.249.212.51]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id CF8BB1885B8 for ; Thu, 22 May 2025 03:32:01 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=45.249.212.51 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1747884723; cv=none; b=W/bp4tozdDmcRHILLN3JP5mqykn5nngzTQNjben22dEcQszIJEaYcludCuCrifresoEBNeLOtJ79dO3B7M9COrmTr51c6n38mS16nzz/RO/EXGQcZC34LDFZG/8W0/tx7VICuQZUyZvTO9MqsYvKbB6GilPHwzqcFkNWsk6UYwY= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1747884723; c=relaxed/simple; bh=gbclfI4Iqifj6sDmzq8wra3KKIr/tGZrpKJaaFJjYnM=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=iT79Jeqk3ZDLWVBOwPcV7pbOr/S7vK37b5SJh98AwlMn0CzhdfNiE4EihA8nIYAaR7uCvuz0jbb/WNo9zFYAz5rD6s3QyswDIwkwPbuj6WpWqvFfCm4iIR9APxDE/cBUGazcbUm9B5keUF5jULRDUNi63fvQ/xdhDluPFSIHlSw= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=huaweicloud.com; spf=pass smtp.mailfrom=huaweicloud.com; arc=none smtp.client-ip=45.249.212.51 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=huaweicloud.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huaweicloud.com Received: from mail.maildlp.com (unknown [172.19.163.216]) by dggsgout11.his.huawei.com (SkyGuard) with ESMTP id 4b2v390DCKz4f3jq5 for ; Thu, 22 May 2025 11:31:33 +0800 (CST) Received: from mail02.huawei.com (unknown [10.116.40.112]) by mail.maildlp.com (Postfix) with ESMTP id E584F1A08FC for ; Thu, 22 May 2025 11:31:52 +0800 (CST) Received: from huaweicloud.com (unknown [10.175.101.6]) by APP1 (Coremail) with SMTP id cCh0CgC3Z3immi5okKq2Mw--.19487S5; Thu, 22 May 2025 11:31:52 +0800 (CST) From: Kemeng Shi To: akpm@linux-foundation.org Cc: kasong@tencent.com, bhe@redhat.com, hannes@cmpxchg.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: [PATCH 3/4] mm: swap: fix potensial buffer overflow in setup_clusters() Date: Thu, 22 May 2025 20:25:53 +0800 Message-Id: <20250522122554.12209-4-shikemeng@huaweicloud.com> X-Mailer: git-send-email 2.30.0 In-Reply-To: <20250522122554.12209-1-shikemeng@huaweicloud.com> References: <20250522122554.12209-1-shikemeng@huaweicloud.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-CM-TRANSID: cCh0CgC3Z3immi5okKq2Mw--.19487S5 X-Coremail-Antispam: 1UD129KBjvJXoW7uFyrtw17JF13KFy8GryDKFg_yoW8Jw4fpF 15Kas8GF4UJr9xKr47CF1kCry3Grn5uay7KFyfAw1a9F1kWrWIgF1Dtrn0yryDKwn5JFyv 9rsrG34UuFsYvwUanT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUmlb4IE77IF4wAFF20E14v26rWj6s0DM7CY07I20VC2zVCF04k2 6cxKx2IYs7xG6rWj6s0DM7CIcVAFz4kK6r1j6r18M280x2IEY4vEnII2IxkI6r1a6r45M2 8IrcIa0xkI8VA2jI8067AKxVWUWwA2048vs2IY020Ec7CjxVAFwI0_Gr0_Xr1l8cAvFVAK 0II2c7xJM28CjxkF64kEwVA0rcxSw2x7M28EF7xvwVC0I7IYx2IY67AKxVWDJVCq3wA2z4 x0Y4vE2Ix0cI8IcVCY1x0267AKxVW8Jr0_Cr1UM28EF7xvwVC2z280aVAFwI0_GcCE3s1l 84ACjcxK6I8E87Iv6xkF7I0E14v26rxl6s0DM2AIxVAIcxkEcVAq07x20xvEncxIr21l5I 8CrVACY4xI64kE6c02F40Ex7xfMcIj6xIIjxv20xvE14v26r1j6r18McIj6I8E87Iv67AK xVWUJVW8JwAm72CE4IkC6x0Yz7v_Jr0_Gr1lF7xvr2IYc2Ij64vIr41lc7CjxVAaw2AFwI 0_JF0_Jw1l42xK82IYc2Ij64vIr41l4c8EcI0Ec7CjxVAaw2AFwI0_JF0_Jw1l4I8I3I0E 4IkC6x0Yz7v_Jr0_Gr1lx2IqxVAqx4xG67AKxVWUJVWUGwC20s026x8GjcxK67AKxVWUGV WUWwC2zVAF1VAY17CE14v26r126r1DMIIYrxkI7VAKI48JMIIF0xvE2Ix0cI8IcVAFwI0_ Jr0_JF4lIxAIcVC0I7IYx2IY6xkF7I0E14v26r4j6F4UMIIF0xvE42xK8VAvwI8IcIk0rV WUJVWUCwCI42IY6I8E87Iv67AKxVWUJVW8JwCI42IY6I8E87Iv6xkF7I0E14v26r4j6r4U JbIYCTnIWIevJa73UjIFyTuYvjxUa75rDUUUU X-CM-SenderInfo: 5vklyvpphqwq5kxd4v5lfo033gof0z/ Content-Type: text/plain; charset="utf-8" In setup_swap_map(), we only ensure badpages are in range (0, last_page]. As maxpages might be < last_page, setup_clusters() will encounter a buffer overflow when a badpage is >=3D maxpages. Only call inc_cluster_info_page() for badpage which is < maxpages to fix the issue. Fixes: b843786b0bd01 ("mm: swapfile: fix SSD detection with swapfile on btr= fs") Signed-off-by: Kemeng Shi Reviewed-by: Baoquan He --- mm/swapfile.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) diff --git a/mm/swapfile.c b/mm/swapfile.c index a82f4ebefca3..63ab9f14b2c6 100644 --- a/mm/swapfile.c +++ b/mm/swapfile.c @@ -3208,9 +3208,13 @@ static struct swap_cluster_info *setup_clusters(stru= ct swap_info_struct *si, * and the EOF part of the last cluster. */ inc_cluster_info_page(si, cluster_info, 0); - for (i =3D 0; i < swap_header->info.nr_badpages; i++) - inc_cluster_info_page(si, cluster_info, - swap_header->info.badpages[i]); + for (i =3D 0; i < swap_header->info.nr_badpages; i++) { + unsigned int page_nr =3D swap_header->info.badpages[i]; + + if (page_nr >=3D maxpages) + continue; + inc_cluster_info_page(si, cluster_info, page_nr); + } for (i =3D maxpages; i < round_up(maxpages, SWAPFILE_CLUSTER); i++) inc_cluster_info_page(si, cluster_info, i); =20 --=20 2.30.0