From patchwork Fri Apr 15 02:14:04 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrew Morton X-Patchwork-Id: 562187 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 93FFCC433FE for ; Fri, 15 Apr 2022 02:14:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1348607AbiDOCQi (ORCPT ); Thu, 14 Apr 2022 22:16:38 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51592 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1348622AbiDOCQh (ORCPT ); Thu, 14 Apr 2022 22:16:37 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6B662B18AE; Thu, 14 Apr 2022 19:14:06 -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 dfw.source.kernel.org (Postfix) with ESMTPS id 037AD621EB; Fri, 15 Apr 2022 02:14:06 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5EBADC385A7; Fri, 15 Apr 2022 02:14:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1649988845; bh=eBBWAnXrVUdhi6HB2GZp6T9EAQR1Og4UhicA+Umrp6E=; h=Date:To:From:In-Reply-To:Subject:From; b=k3qjibzzNtJShJVheS/MtFb3s5dnZMgNnC7Uvf9vgugDT+ZLPGgTOjdAntB9evZp0 HbtoPg/Wc/8mIXETw8DTz+kzj6w7RS9AwdVAYFXoBWLRB4A6NxSOJEC7XutmbN3UCt f1Lo4iLlZOEJm0rUWWUnOItXBggfRnsuzk9DFDQ0= Date: Thu, 14 Apr 2022 19:14:04 -0700 To: stable@vger.kernel.org, catalin.marinas@arm.com, patrick.wang.shcn@gmail.com, akpm@linux-foundation.org, patches@lists.linux.dev, linux-mm@kvack.org, mm-commits@vger.kernel.org, torvalds@linux-foundation.org, akpm@linux-foundation.org From: Andrew Morton In-Reply-To: <20220414191240.9f86d15a3e3afd848a9839a6@linux-foundation.org> Subject: [patch 14/14] mm: kmemleak: take a full lowmem check in kmemleak_*_phys() Message-Id: <20220415021405.5EBADC385A7@smtp.kernel.org> Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Patrick Wang Subject: mm: kmemleak: take a full lowmem check in kmemleak_*_phys() The kmemleak_*_phys() apis do not check the address for lowmem's min boundary, while the caller may pass an address below lowmem, which will trigger an oops: # echo scan > /sys/kernel/debug/kmemleak [ 54.888353] Unable to handle kernel paging request at virtual address ff5fffffffe00000 [ 54.888932] Oops [#1] [ 54.889102] Modules linked in: [ 54.889326] CPU: 2 PID: 134 Comm: bash Not tainted 5.18.0-rc1-next-20220407 #33 [ 54.889620] Hardware name: riscv-virtio,qemu (DT) [ 54.889901] epc : scan_block+0x74/0x15c [ 54.890215] ra : scan_block+0x72/0x15c [ 54.890390] epc : ffffffff801e5806 ra : ffffffff801e5804 sp : ff200000104abc30 [ 54.890607] gp : ffffffff815cd4e8 tp : ff60000004cfa340 t0 : 0000000000000200 [ 54.890835] t1 : 00aaaaaac23954cc t2 : 00000000000003ff s0 : ff200000104abc90 [ 54.891024] s1 : ffffffff81b0ff28 a0 : 0000000000000000 a1 : ff5fffffffe01000 [ 54.891201] a2 : ffffffff81b0ff28 a3 : 0000000000000002 a4 : 0000000000000001 [ 54.891377] a5 : 0000000000000000 a6 : ff200000104abd7c a7 : 0000000000000005 [ 54.891552] s2 : ff5fffffffe00ff9 s3 : ffffffff815cd998 s4 : ffffffff815d0e90 [ 54.891727] s5 : ffffffff81b0ff28 s6 : 0000000000000020 s7 : ffffffff815d0eb0 [ 54.891903] s8 : ffffffffffffffff s9 : ff5fffffffe00000 s10: ff5fffffffe01000 [ 54.892078] s11: 0000000000000022 t3 : 00ffffffaa17db4c t4 : 000000000000000f [ 54.892271] t5 : 0000000000000001 t6 : 0000000000000000 [ 54.892408] status: 0000000000000100 badaddr: ff5fffffffe00000 cause: 000000000000000d [ 54.892643] [] scan_gray_list+0x12e/0x1a6 [ 54.892824] [] kmemleak_scan+0x2aa/0x57e [ 54.892961] [] kmemleak_write+0x32a/0x40c [ 54.893096] [] full_proxy_write+0x56/0x82 [ 54.893235] [] vfs_write+0xa6/0x2a6 [ 54.893362] [] ksys_write+0x6c/0xe2 [ 54.893487] [] sys_write+0x22/0x2a [ 54.893609] [] ret_from_syscall+0x0/0x2 [ 54.894183] ---[ end trace 0000000000000000 ]--- The callers may not quite know the actual address they pass(e.g. from devicetree). So the kmemleak_*_phys() apis should guarantee the address they finally use is in lowmem range, so check the address for lowmem's min boundary. Link: https://lkml.kernel.org/r/20220413122925.33856-1-patrick.wang.shcn@gmail.com Signed-off-by: Patrick Wang Acked-by: Catalin Marinas Cc: Signed-off-by: Andrew Morton --- mm/kmemleak.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) --- a/mm/kmemleak.c~mm-kmemleak-take-a-full-lowmem-check-in-kmemleak__phys +++ a/mm/kmemleak.c @@ -1132,7 +1132,7 @@ EXPORT_SYMBOL(kmemleak_no_scan); void __ref kmemleak_alloc_phys(phys_addr_t phys, size_t size, int min_count, gfp_t gfp) { - if (!IS_ENABLED(CONFIG_HIGHMEM) || PHYS_PFN(phys) < max_low_pfn) + if (PHYS_PFN(phys) >= min_low_pfn && PHYS_PFN(phys) < max_low_pfn) kmemleak_alloc(__va(phys), size, min_count, gfp); } EXPORT_SYMBOL(kmemleak_alloc_phys); @@ -1146,7 +1146,7 @@ EXPORT_SYMBOL(kmemleak_alloc_phys); */ void __ref kmemleak_free_part_phys(phys_addr_t phys, size_t size) { - if (!IS_ENABLED(CONFIG_HIGHMEM) || PHYS_PFN(phys) < max_low_pfn) + if (PHYS_PFN(phys) >= min_low_pfn && PHYS_PFN(phys) < max_low_pfn) kmemleak_free_part(__va(phys), size); } EXPORT_SYMBOL(kmemleak_free_part_phys); @@ -1158,7 +1158,7 @@ EXPORT_SYMBOL(kmemleak_free_part_phys); */ void __ref kmemleak_not_leak_phys(phys_addr_t phys) { - if (!IS_ENABLED(CONFIG_HIGHMEM) || PHYS_PFN(phys) < max_low_pfn) + if (PHYS_PFN(phys) >= min_low_pfn && PHYS_PFN(phys) < max_low_pfn) kmemleak_not_leak(__va(phys)); } EXPORT_SYMBOL(kmemleak_not_leak_phys); @@ -1170,7 +1170,7 @@ EXPORT_SYMBOL(kmemleak_not_leak_phys); */ void __ref kmemleak_ignore_phys(phys_addr_t phys) { - if (!IS_ENABLED(CONFIG_HIGHMEM) || PHYS_PFN(phys) < max_low_pfn) + if (PHYS_PFN(phys) >= min_low_pfn && PHYS_PFN(phys) < max_low_pfn) kmemleak_ignore(__va(phys)); } EXPORT_SYMBOL(kmemleak_ignore_phys);