From patchwork Thu Sep 16 15:28:18 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mark Brown X-Patchwork-Id: 45090 Return-Path: X-Original-To: patchwork@sourceware.org Delivered-To: patchwork@sourceware.org Received: from server2.sourceware.org (localhost [IPv6:::1]) by sourceware.org (Postfix) with ESMTP id EFD55385843C for ; Thu, 16 Sep 2021 15:31:40 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org EFD55385843C DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1631806301; bh=4ULEXXlCfdBwVjij4MrK9fgaU7duHAyc8FKur+F6k3E=; h=To:Subject:Date:In-Reply-To:References:List-Id:List-Unsubscribe: List-Archive:List-Post:List-Help:List-Subscribe:From:Reply-To:Cc: From; b=QYmWsf9+Fp5tk9NfQNSXyN1bHGFS16WIbrq5l0e8bV0nw2GdZxcaDO+tB151OVDfS qTh92Oukw090PNYcmputXn5V7bmeSp+UhyMYFFq9JBfHgL4+w/F+LGZuB44tUvWZjN SfAa1W7s2+Dq9pCow8s3mZBNYA7NLl8nhcyrYWCg= X-Original-To: libc-alpha@sourceware.org Delivered-To: libc-alpha@sourceware.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by sourceware.org (Postfix) with ESMTPS id 60E65385800C for ; Thu, 16 Sep 2021 15:30:37 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org 60E65385800C Received: by mail.kernel.org (Postfix) with ESMTPSA id 1A18960D07; Thu, 16 Sep 2021 15:30:35 +0000 (UTC) To: Catalin Marinas , Will Deacon Subject: [PATCH v6 1/4] elf: Allow architectures to parse properties on the main executable Date: Thu, 16 Sep 2021 16:28:18 +0100 Message-Id: <20210916152821.1153-2-broonie@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20210916152821.1153-1-broonie@kernel.org> References: <20210916152821.1153-1-broonie@kernel.org> MIME-Version: 1.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=5824; h=from:subject; bh=e9yCCLO92N7HRfaC4YRIYtoCOTLa2gCo7SJPmKuBp6g=; b=owEBbQGS/pANAwAKASTWi3JdVIfQAcsmYgBhQ2KRd8LGZVDGxxxRRbghUIJa85La2sO6Z8zwZc85 5dnO+iqJATMEAAEKAB0WIQSt5miqZ1cYtZ/in+ok1otyXVSH0AUCYUNikQAKCRAk1otyXVSH0HDRB/ 0fGE94ShnNwWbZuP8+kXIrfzrFkmEVrLLVVd2/SnZtS1Ft0xrJ4QPyveG7eGr3lWJ/NwQFFrzdbuUw 21VjjUIH3ewa+8WqbJrj9Sl1AmCq/2ygiqxQ/OjXgeIaeosiOs0lBbPnCQIDaSGXGSnIAxiS6wZl9D TkOpKujnBasuiN3s3KERTAPFWLS/lX1ucBcQbdVl2Q4ox/FzircUE5vb02kefFogzU3TZKVSS4mC/P QU9P0z/uQFH7mbKE3myZEjZyyyuu71DQxy1eOj8f16k2vbVKBj0Bilt3JHOlu+5EKRGC4dVOjuyft8 NYI1ZHPBD4yZuuLECRDXMLl6+x8YWb X-Developer-Key: i=broonie@kernel.org; a=openpgp; fpr=3F2568AAC26998F9E813A1C5C3F436CA30F5D8EB X-Spam-Status: No, score=-11.6 required=5.0 tests=BAYES_00, DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, GIT_PATCH_0, SPF_HELO_NONE, SPF_PASS, TXREP autolearn=ham autolearn_force=no version=3.4.4 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on server2.sourceware.org X-BeenThere: libc-alpha@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Libc-alpha mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-Patchwork-Original-From: Mark Brown via Libc-alpha From: Mark Brown Reply-To: Mark Brown Cc: linux-arch@vger.kernel.org, Yu-cheng Yu , libc-alpha@sourceware.org, Szabolcs Nagy , Jeremy Linton , Mark Brown , Dave Martin , linux-arm-kernel@lists.infradead.org Errors-To: libc-alpha-bounces+patchwork=sourceware.org@sourceware.org Sender: "Libc-alpha" 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 a new flag is_interp flag as with arch_elf_adjust_prot() and calling it for both the main executable and any intepreter. The user of this code, arm64, is adapted to ensure that there is no functional change. Signed-off-by: Mark Brown Tested-by: Jeremy Linton Reviewed-by: Dave Martin --- arch/arm64/include/asm/elf.h | 3 ++- fs/binfmt_elf.c | 27 +++++++++++++++++++-------- include/linux/elf.h | 4 +++- 3 files changed, 24 insertions(+), 10 deletions(-) diff --git a/arch/arm64/include/asm/elf.h b/arch/arm64/include/asm/elf.h index 97932fbf973d..5cc002376abe 100644 --- a/arch/arm64/include/asm/elf.h +++ b/arch/arm64/include/asm/elf.h @@ -259,6 +259,7 @@ 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 */ @@ -271,7 +272,7 @@ 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 69d900a8473d..1b2d0fc87ad4 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; @@ -963,12 +968,11 @@ 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 +983,17 @@ 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, 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