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 X-Spam-Level: X-Spam-Status: No, score=-19.7 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3175DC07E9C for ; Mon, 12 Jul 2021 11:57:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 129B6610FA for ; Mon, 12 Jul 2021 11:57:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230207AbhGLMAI (ORCPT ); Mon, 12 Jul 2021 08:00:08 -0400 Received: from mail.kernel.org ([198.145.29.99]:32990 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234637AbhGLL7q (ORCPT ); Mon, 12 Jul 2021 07:59:46 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 93CC561106; Mon, 12 Jul 2021 11:56:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1626091018; bh=UuQT7MuELYKmhnUM/9E0W1LTcaYRAh38M3lJ7n5Epv8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Vf2MA1DQKEXhlDGR4yCSFSB/bP0FI92+7GLqQnJO+rhIk8pXi8NH6fd7SEF4IF/2Z kNE1rCiUoICSf8B8YeLfU8h3ydoU92JQM+4/yQ0qapP+ocjJtZGY9DIvyeb4DBS6wm 8fhxBIa1BDb7XxzmyXyCHUV94GFlV5EmxsNkHAHbyErmxTG06WAXrFdCFxlDm7+iL8 vuk5OWt63fwg8ANb7SW4KeVmSjaXhz3LnEpzNcWAMOSCpUGpx9CrEUXzf1ulOSwEA5 ZMMAYeIT18madM8eWeJLrXK9OhM41LjmAFmT9qXQ7r7k33qzb6fr3fQmM/y/2lF7h2 61IZ9s3gQi47A== From: Mark Brown To: Catalin Marinas , Will Deacon Cc: Szabolcs Nagy , Jeremy Linton , Dave Martin , "H . J . Lu" , Yu-cheng Yu , linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, libc-alpha@sourceware.org, Mark Brown Subject: [PATCH v4 1/4] elf: Allow architectures to parse properties on the main executable Date: Mon, 12 Jul 2021 12:52:56 +0100 Message-Id: <20210712115259.29547-2-broonie@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20210712115259.29547-1-broonie@kernel.org> References: <20210712115259.29547-1-broonie@kernel.org> MIME-Version: 1.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=6014; h=from:subject; bh=UuQT7MuELYKmhnUM/9E0W1LTcaYRAh38M3lJ7n5Epv8=; b=owEBbQGS/pANAwAKASTWi3JdVIfQAcsmYgBg7C0XKSWKoWKSPHkFHbhY+rhHSEcUKON/1AdxApOU nvYqkrSJATMEAAEKAB0WIQSt5miqZ1cYtZ/in+ok1otyXVSH0AUCYOwtFwAKCRAk1otyXVSH0GJxB/ 9mSG7Xe92bWYUDIopC1+wKTpxWK4nG+sycce8CuhIXxW8QLi8ooPOVa1Qs4izOFt9X9AeegUHpVGYE u0E+xku3/B+eANTaX6S3gZ2OAWfsDG6bRcwYzbB6vyEaD+TDrb7IZBEfv+1VQMlM7FEvEZDOMJ7ozA yqXvs/f5+YKwAVy1VXVEOGeP/LRVq9cfp+F6Bm/3MuVlDyEKUPGw2wDdZ4ml8ejvkVkwu9/KPxpYKi 5KyuZ31x6nqLxE5l39GIXf3UXV59BmrVHW2NVKywqWk6gTkg0GpBcUmn9VvDex+mTYo073rtEJAvGE rg5Pp70euJ182MNT1Nc5xl9f6rFq1R X-Developer-Key: i=broonie@kernel.org; a=openpgp; fpr=3F2568AAC26998F9E813A1C5C3F436CA30F5D8EB Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-arch@vger.kernel.org Currently the ELF code only attempts to parse properties on the image that will start execution, either the interpreter or for statically linked executables the main executable. The expectation is that any property handling for the main executable will be done by the interpreter. This is a bit inconsistent since we do map the executable and is causing problems for the arm64 BTI support when used in conjunction with systemd's use of seccomp to implement MemoryDenyWriteExecute which stops the dynamic linker adjusting the permissions of executable segments. Allow architectures to handle properties for both the dynamic linker and main executable, adjusting arch_parse_elf_properties() to have an is_interp flag as with arch_elf_adjust_prot() and calling it for both the main executable and any intepreter. Signed-off-by: Mark Brown Tested-by: Jeremy Linton --- arch/arm64/include/asm/elf.h | 3 ++- fs/binfmt_elf.c | 31 +++++++++++++++++++++++-------- include/linux/elf.h | 4 +++- 3 files changed, 28 insertions(+), 10 deletions(-) diff --git a/arch/arm64/include/asm/elf.h b/arch/arm64/include/asm/elf.h index 8d1c8dcb87fd..a488a1329b16 100644 --- a/arch/arm64/include/asm/elf.h +++ b/arch/arm64/include/asm/elf.h @@ -261,6 +261,7 @@ struct arch_elf_state { static inline int arch_parse_elf_property(u32 type, const void *data, size_t datasz, bool compat, + bool has_interp, bool is_interp, struct arch_elf_state *arch) { /* No known properties for AArch32 yet */ @@ -273,7 +274,7 @@ static inline int arch_parse_elf_property(u32 type, const void *data, if (datasz != sizeof(*p)) return -ENOEXEC; - if (system_supports_bti() && + if (system_supports_bti() && has_interp == is_interp && (*p & GNU_PROPERTY_AARCH64_FEATURE_1_BTI)) arch->flags |= ARM64_ELF_BTI; } diff --git a/fs/binfmt_elf.c b/fs/binfmt_elf.c index 439ed81e755a..81e151a57df2 100644 --- a/fs/binfmt_elf.c +++ b/fs/binfmt_elf.c @@ -716,8 +716,9 @@ static unsigned long load_elf_interp(struct elfhdr *interp_elf_ex, */ static int parse_elf_property(const char *data, size_t *off, size_t datasz, - struct arch_elf_state *arch, - bool have_prev_type, u32 *prev_type) + struct arch_elf_state *arch, bool has_interp, + bool is_interp, bool have_prev_type, + u32 *prev_type) { size_t o, step; const struct gnu_property *pr; @@ -751,7 +752,8 @@ static int parse_elf_property(const char *data, size_t *off, size_t datasz, *prev_type = pr->pr_type; ret = arch_parse_elf_property(pr->pr_type, data + o, - pr->pr_datasz, ELF_COMPAT, arch); + pr->pr_datasz, ELF_COMPAT, + has_interp, is_interp, arch); if (ret) return ret; @@ -764,6 +766,7 @@ static int parse_elf_property(const char *data, size_t *off, size_t datasz, #define NOTE_NAME_SZ (sizeof(GNU_PROPERTY_TYPE_0_NAME)) static int parse_elf_properties(struct file *f, const struct elf_phdr *phdr, + bool has_interp, bool is_interp, struct arch_elf_state *arch) { union { @@ -813,7 +816,8 @@ static int parse_elf_properties(struct file *f, const struct elf_phdr *phdr, have_prev_type = false; do { ret = parse_elf_property(note.data, &off, datasz, arch, - have_prev_type, &prev_type); + has_interp, is_interp, have_prev_type, + &prev_type); have_prev_type = true; } while (!ret); @@ -828,6 +832,7 @@ static int load_elf_binary(struct linux_binprm *bprm) unsigned long error; struct elf_phdr *elf_ppnt, *elf_phdata, *interp_elf_phdata = NULL; struct elf_phdr *elf_property_phdata = NULL; + struct elf_phdr *interp_elf_property_phdata = NULL; unsigned long elf_bss, elf_brk; int bss_prot = 0; int retval, i; @@ -936,6 +941,10 @@ static int load_elf_binary(struct linux_binprm *bprm) executable_stack = EXSTACK_DISABLE_X; break; + case PT_GNU_PROPERTY: + elf_property_phdata = elf_ppnt; + break; + case PT_LOPROC ... PT_HIPROC: retval = arch_elf_pt_proc(elf_ex, elf_ppnt, bprm->file, false, @@ -963,12 +972,11 @@ static int load_elf_binary(struct linux_binprm *bprm) goto out_free_dentry; /* Pass PT_LOPROC..PT_HIPROC headers to arch code */ - elf_property_phdata = NULL; elf_ppnt = interp_elf_phdata; for (i = 0; i < interp_elf_ex->e_phnum; i++, elf_ppnt++) switch (elf_ppnt->p_type) { case PT_GNU_PROPERTY: - elf_property_phdata = elf_ppnt; + interp_elf_property_phdata = elf_ppnt; break; case PT_LOPROC ... PT_HIPROC: @@ -979,10 +987,17 @@ static int load_elf_binary(struct linux_binprm *bprm) goto out_free_dentry; break; } + + retval = parse_elf_properties(interpreter, + interp_elf_property_phdata, + true, true, &arch_state); + if (retval) + goto out_free_dentry; + } - retval = parse_elf_properties(interpreter ?: bprm->file, - elf_property_phdata, &arch_state); + retval = parse_elf_properties(bprm->file, elf_property_phdata, + interpreter != NULL, false, &arch_state); if (retval) goto out_free_dentry; diff --git a/include/linux/elf.h b/include/linux/elf.h index c9a46c4e183b..1c45ecf29147 100644 --- a/include/linux/elf.h +++ b/include/linux/elf.h @@ -88,13 +88,15 @@ struct arch_elf_state; #ifndef CONFIG_ARCH_USE_GNU_PROPERTY static inline int arch_parse_elf_property(u32 type, const void *data, size_t datasz, bool compat, + bool has_interp, bool is_interp, struct arch_elf_state *arch) { return 0; } #else extern int arch_parse_elf_property(u32 type, const void *data, size_t datasz, - bool compat, struct arch_elf_state *arch); + bool compat, bool has_interp, bool is_interp, + struct arch_elf_state *arch); #endif #ifdef CONFIG_ARCH_HAVE_ELF_PROT -- 2.20.1