From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) (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 B5183278161 for ; Sun, 21 Dec 2025 08:58:30 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.129.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1766307512; cv=none; b=OEvyixNUBdT6w9226Xka010fNFCMkVYnx8yBLFOxEp156Z1VqG9tSBdB2Grgm3HcuKmrrinI3oEiz8kprNNx+DWfULgQE2fvau3PlU5FzOM2cN8F8/YLB67jhKXOyazv0A6cHOgWvuTnTeHNakuO2W64qzD3IDRLoqJplLm+1tg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1766307512; c=relaxed/simple; bh=o+tUNFsOPBKIzPT9dgU1YaSzNI6zIu1kIaWgdAmDLh4=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=sXrD8kqJFSa9hb4wIH4n5Vku2eJdKJIa4ql4uMz8FXt+Tw/FeFpfC1WWVe2/CezJ4XxTC5ULsFjK9evyHvlRc3yXLLELj7WkB3T4D3V7LhBBb/3ex3zz2DyK7f7234eSr0ww7EaZSnGzqx9tWsNr2Lv3DtDeXZT1Z8WWB258wP4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=XuOu1s94; arc=none smtp.client-ip=170.10.129.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="XuOu1s94" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1766307509; 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: in-reply-to:in-reply-to:references:references; bh=tSork19nHW6YKdr7H91m897S5X3FouxxKb6TE2rVX6g=; b=XuOu1s9458XM8UP5mD0QgAX3AYP38Nqjt8VqZgSu5SVXoz5WrTSh20HFlLUzPOmeAVyknu dPld/Hn12KNMl9hApZLV44ptJ4XhdZpp6L1yShJZPxz3aY1cGd2zoQLjP8wjzLxYlp0zqo 0RjBELVVreDUQPsdunHTJMDVTBzhSwo= Received: from mx-prod-mc-05.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-253-85XfBGhFNiSN_qbv9wHraw-1; Sun, 21 Dec 2025 03:58:24 -0500 X-MC-Unique: 85XfBGhFNiSN_qbv9wHraw-1 X-Mimecast-MFC-AGG-ID: 85XfBGhFNiSN_qbv9wHraw_1766307502 Received: from mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.4]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-05.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 7C2B6195608A; Sun, 21 Dec 2025 08:58:22 +0000 (UTC) Received: from dell-per7425-02.rhts.eng.pek2.redhat.com (dell-per7425-02.rhts.eng.pek2.redhat.com [10.73.116.18]) by mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id A1DA430001A2; Sun, 21 Dec 2025 08:58:18 +0000 (UTC) From: Li Wang To: akpm@linux-foundation.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org Cc: David Hildenbrand , Mark Brown , Shuah Khan , Waiman Long Subject: [PATCH v2 1/3] selftests/mm/write_to_hugetlbfs: parse -s as size_t Date: Sun, 21 Dec 2025 16:58:08 +0800 Message-ID: <20251221085810.3163919-2-liwang@redhat.com> In-Reply-To: <20251221085810.3163919-1-liwang@redhat.com> References: <20251221085810.3163919-1-liwang@redhat.com> Precedence: bulk X-Mailing-List: linux-kselftest@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.4 write_to_hugetlbfs currently parses the -s size argument with atoi() into an int. This silently accepts malformed input, cannot report overflow, and can truncate large sizes. --- Error log --- # uname -r 6.12.0-xxx.el10.aarch64+64k # ls /sys/kernel/mm/hugepages/hugepages-* hugepages-16777216kB/ hugepages-2048kB/ hugepages-524288kB/ #./charge_reserved_hugetlb.sh -cgroup-v2 # ----------------------------------------- ... # nr hugepages = 10 # writing cgroup limit: 5368709120 # writing reseravation limit: 5368709120 ... # Writing to this path: /mnt/huge/test # Writing this size: -1610612736 <-------- Switch the size variable to size_t and parse -s with sscanf("%zu", ...). Also print the size using %zu. This avoids incorrect behavior with large -s values and makes the utility more robust. Signed-off-by: Li Wang Cc: David Hildenbrand Cc: Mark Brown Cc: Shuah Khan Cc: Waiman Long --- tools/testing/selftests/mm/write_to_hugetlbfs.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/tools/testing/selftests/mm/write_to_hugetlbfs.c b/tools/testing/selftests/mm/write_to_hugetlbfs.c index 34c91f7e6128..ecb5f7619960 100644 --- a/tools/testing/selftests/mm/write_to_hugetlbfs.c +++ b/tools/testing/selftests/mm/write_to_hugetlbfs.c @@ -68,7 +68,7 @@ int main(int argc, char **argv) int key = 0; int *ptr = NULL; int c = 0; - int size = 0; + size_t size = 0; char path[256] = ""; enum method method = MAX_METHOD; int want_sleep = 0, private = 0; @@ -86,7 +86,10 @@ int main(int argc, char **argv) while ((c = getopt(argc, argv, "s:p:m:owlrn")) != -1) { switch (c) { case 's': - size = atoi(optarg); + if (sscanf(optarg, "%zu", &size) != 1) { + perror("Invalid -s."); + exit_usage(); + } break; case 'p': strncpy(path, optarg, sizeof(path) - 1); @@ -131,7 +134,7 @@ int main(int argc, char **argv) } if (size != 0) { - printf("Writing this size: %d\n", size); + printf("Writing this size: %zu\n", size); } else { errno = EINVAL; perror("size not found"); -- 2.49.0