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 05525C4332F for ; Wed, 4 Jan 2023 16:18:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239881AbjADQR6 (ORCPT ); Wed, 4 Jan 2023 11:17:58 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40898 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239928AbjADQRv (ORCPT ); Wed, 4 Jan 2023 11:17:51 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 00D733C392 for ; Wed, 4 Jan 2023 08:17:50 -0800 (PST) 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 A305AB81714 for ; Wed, 4 Jan 2023 16:17:49 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0AEBFC433D2; Wed, 4 Jan 2023 16:17:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1672849068; bh=HsmmxbNkHCgGHsI98GPa9WHHyax3G6n05cueTPaHuxU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=p88lgAVT2D2WrNo/tsF+XFW3fxwoFy94r7RHWtBQZfSDhQjj8hvWIm2N6savxi7kW YO1eurLrRgZjnRxY4xk7o34B1tk7KSn/RQJg/uprxhbKFIx/ssXnLJvAyh5VF+nBX6 jZPhP5piaXv8914sqm4/q+RMpa1Lx/HdQOfSO040= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Li Huafei , Conor Dooley , Liao Chang , Palmer Dabbelt Subject: [PATCH 6.1 128/207] RISC-V: kexec: Fix memory leak of fdt buffer Date: Wed, 4 Jan 2023 17:06:26 +0100 Message-Id: <20230104160515.980633215@linuxfoundation.org> X-Mailer: git-send-email 2.39.0 In-Reply-To: <20230104160511.905925875@linuxfoundation.org> References: <20230104160511.905925875@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Li Huafei commit 96df59b1ae23f5c11698c3c2159aeb2ecd4944a4 upstream. This is reported by kmemleak detector: unreferenced object 0xff60000082864000 (size 9588): comm "kexec", pid 146, jiffies 4294900634 (age 64.788s) hex dump (first 32 bytes): d0 0d fe ed 00 00 12 ed 00 00 00 48 00 00 11 40 ...........H...@ 00 00 00 28 00 00 00 11 00 00 00 02 00 00 00 00 ...(............ backtrace: [<00000000f95b17c4>] kmemleak_alloc+0x34/0x3e [<00000000b9ec8e3e>] kmalloc_order+0x9c/0xc4 [<00000000a95cf02e>] kmalloc_order_trace+0x34/0xb6 [<00000000f01e68b4>] __kmalloc+0x5c2/0x62a [<000000002bd497b2>] kvmalloc_node+0x66/0xd6 [<00000000906542fa>] of_kexec_alloc_and_setup_fdt+0xa6/0x6ea [<00000000e1166bde>] elf_kexec_load+0x206/0x4ec [<0000000036548e09>] kexec_image_load_default+0x40/0x4c [<0000000079fbe1b4>] sys_kexec_file_load+0x1c4/0x322 [<0000000040c62c03>] ret_from_syscall+0x0/0x2 In elf_kexec_load(), a buffer is allocated via kvmalloc() to store fdt. While it's not freed back to system when kexec kernel is reloaded or unloaded. Then memory leak is caused. Fix it by introducing riscv specific function arch_kimage_file_post_load_cleanup(), and freeing the buffer there. Fixes: 6261586e0c91 ("RISC-V: Add kexec_file support") Signed-off-by: Li Huafei Reviewed-by: Conor Dooley Reviewed-by: Liao Chang Link: https://lore.kernel.org/r/20221104095658.141222-1-lihuafei1@huawei.com Cc: stable@vger.kernel.org Signed-off-by: Palmer Dabbelt Signed-off-by: Greg Kroah-Hartman --- arch/riscv/include/asm/kexec.h | 5 +++++ arch/riscv/kernel/elf_kexec.c | 10 ++++++++++ 2 files changed, 15 insertions(+) --- a/arch/riscv/include/asm/kexec.h +++ b/arch/riscv/include/asm/kexec.h @@ -39,6 +39,7 @@ crash_setup_regs(struct pt_regs *newregs #define ARCH_HAS_KIMAGE_ARCH struct kimage_arch { + void *fdt; /* For CONFIG_KEXEC_FILE */ unsigned long fdt_addr; }; @@ -62,6 +63,10 @@ int arch_kexec_apply_relocations_add(str const Elf_Shdr *relsec, const Elf_Shdr *symtab); #define arch_kexec_apply_relocations_add arch_kexec_apply_relocations_add + +struct kimage; +int arch_kimage_file_post_load_cleanup(struct kimage *image); +#define arch_kimage_file_post_load_cleanup arch_kimage_file_post_load_cleanup #endif #endif --- a/arch/riscv/kernel/elf_kexec.c +++ b/arch/riscv/kernel/elf_kexec.c @@ -21,6 +21,14 @@ #include #include +int arch_kimage_file_post_load_cleanup(struct kimage *image) +{ + kvfree(image->arch.fdt); + image->arch.fdt = NULL; + + return kexec_image_post_load_cleanup_default(image); +} + static int riscv_kexec_elf_load(struct kimage *image, struct elfhdr *ehdr, struct kexec_elf_info *elf_info, unsigned long old_pbase, unsigned long new_pbase) @@ -298,6 +306,8 @@ static void *elf_kexec_load(struct kimag pr_err("Error add DTB kbuf ret=%d\n", ret); goto out_free_fdt; } + /* Cache the fdt buffer address for memory cleanup */ + image->arch.fdt = fdt; pr_notice("Loaded device tree at 0x%lx\n", kbuf.mem); goto out;