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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id ED323C433FE for ; Thu, 14 Apr 2022 20:17:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1346202AbiDNUT4 (ORCPT ); Thu, 14 Apr 2022 16:19:56 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33162 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1346204AbiDNUTz (ORCPT ); Thu, 14 Apr 2022 16:19:55 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E4D04EB0A0; Thu, 14 Apr 2022 13:17:29 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 30CE2B82BA0; Thu, 14 Apr 2022 20:17:28 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id D1455C385A8; Thu, 14 Apr 2022 20:17:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1649967446; bh=HMdxUp7k2/UnGFC7Cr1IqkkBWFss7+czuc2zo5txfGo=; h=Date:To:From:Subject:From; b=MtvRE6xxvWJXS782z2AgleZjMop/LBtM4eWz0N1v5apXw9YlajxTRQOcU7nWEuMOn hu9BOGqlFekkWK3/ckBP5Mt7Mb0yRgm7/Lirca7Cd3S8kqHU5F2yJ3BefkFZ1fKByh 7hGfMXiQer1KyEZ61zDCnhbQfqb4KkpmK6Jrl9V0= Date: Thu, 14 Apr 2022 13:17:26 -0700 To: mm-commits@vger.kernel.org, stable@vger.kernel.org, shuah@kernel.org, sidhartha.kumar@oracle.com, akpm@linux-foundation.org From: Andrew Morton Subject: + selftest-vm-verify-mmap-addr-in-mremap_test.patch added to -mm tree Message-Id: <20220414201726.D1455C385A8@smtp.kernel.org> Precedence: bulk Reply-To: linux-kernel@vger.kernel.org List-ID: X-Mailing-List: mm-commits@vger.kernel.org The patch titled Subject: selftest/vm: verify mmap addr in mremap_test has been added to the -mm tree. Its filename is selftest-vm-verify-mmap-addr-in-mremap_test.patch This patch should soon appear at https://ozlabs.org/~akpm/mmots/broken-out/selftest-vm-verify-mmap-addr-in-mremap_test.patch and later at https://ozlabs.org/~akpm/mmotm/broken-out/selftest-vm-verify-mmap-addr-in-mremap_test.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: Sidhartha Kumar Subject: selftest/vm: verify mmap addr in mremap_test Patch series "selftest/vm fix segfault in mremap_test". Avoid calling mmap with requested addresses that are less than the system's mmap_min_addr. Running the test as root returns EACCES when trying to map addresses < mmap_min_addr which is not one of the error codes for the retry condition. Add a munmap call after an alignment check as the mappings are retained after the retry and can reach vm.max_map_count. Link: https://lkml.kernel.org/r/20220414171529.62058-1-sidhartha.kumar@oracle.com Link: https://lkml.kernel.org/r/20220414171529.62058-2-sidhartha.kumar@oracle.com Signed-off-by: Sidhartha Kumar Cc: Shuah Khan Cc: Signed-off-by: Andrew Morton --- --- a/tools/testing/selftests/vm/mremap_test.c~selftest-vm-verify-mmap-addr-in-mremap_test +++ a/tools/testing/selftests/vm/mremap_test.c @@ -6,6 +6,7 @@ #include #include +#include #include #include #include @@ -63,6 +64,35 @@ enum { .expect_failure = should_fail \ } +/* Returns mmap_min_addr sysctl */ +static unsigned long long get_mmap_min_addr(void) +{ + FILE *fp; + int n_matched; + static unsigned long long addr; + + if (addr) + return addr; + + fp = fopen("/proc/sys/vm/mmap_min_addr", "r"); + if (fp == NULL) { + ksft_print_msg("Failed to open /proc/sys/vm/mmap_min_addr: %s\n", + strerror(errno)); + exit(KSFT_SKIP); + } + + n_matched = fscanf(fp, "%llu", &addr); + if (n_matched != 1) { + ksft_print_msg("Failed to read /proc/sys/vm/mmap_min_addr: %s\n", + strerror(errno)); + fclose(fp); + exit(KSFT_SKIP); + } + + fclose(fp); + return addr; +} + /* * Returns the start address of the mapping on success, else returns * NULL on failure. @@ -71,8 +101,15 @@ static void *get_source_mapping(struct c { unsigned long long addr = 0ULL; void *src_addr = NULL; + unsigned long long mmap_min_addr; + + mmap_min_addr = get_mmap_min_addr(); + retry: addr += c.src_alignment; + if (addr < mmap_min_addr) + goto retry; + src_addr = mmap((void *) addr, c.region_size, PROT_READ | PROT_WRITE, MAP_FIXED_NOREPLACE | MAP_ANONYMOUS | MAP_SHARED, -1, 0); @@ -90,8 +127,10 @@ retry: * alignment in the tests. */ if (((unsigned long long) src_addr & (c.src_alignment - 1)) || - !((unsigned long long) src_addr & c.src_alignment)) + !((unsigned long long) src_addr & c.src_alignment)) { + munmap(src_addr, c.region_size); goto retry; + } if (!src_addr) goto error; _ Patches currently in -mm which might be from sidhartha.kumar@oracle.com are selftest-vm-verify-mmap-addr-in-mremap_test.patch selftest-vm-verify-remap-destination-address-in-mremap_test.patch selftest-vm-support-xfail-in-mremap_test.patch selftest-vm-add-skip-support-to-mremap_test.patch selftest-vm-clarify-error-statement-in-gup_test.patch