From nobody Tue Sep 16 14:27:11 2025 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 85138C46467 for ; Tue, 3 Jan 2023 17:01:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238371AbjACRBZ (ORCPT ); Tue, 3 Jan 2023 12:01:25 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41520 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238249AbjACRAN (ORCPT ); Tue, 3 Jan 2023 12:00:13 -0500 Received: from fx303.security-mail.net (mxout.security-mail.net [85.31.212.46]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CB24013CFD for ; Tue, 3 Jan 2023 09:00:05 -0800 (PST) Received: from localhost (fx303.security-mail.net [127.0.0.1]) by fx303.security-mail.net (Postfix) with ESMTP id 7C84930F79C for ; Tue, 3 Jan 2023 17:44:33 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kalray.eu; s=sec-sig-email; t=1672764273; bh=SJrsZK0M0X81Fk2xCXQchFKLufczF4Qkt6HtsbNuJRQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=KBlPF4RfK847fWnKxIocRyIXqmqYRxizrH8je8jUZOutWrsJQ0omjF4J43rZTsQao IYCaC8YMiuCTzaJRFUEuXHzUg3otnowO0VVzwjFQtWmtSe+m9Erx5L61uqbdMW3Ocl u0Fi6LKotTa09bUVzIMM1ywhVtJVDKfr97U0SeJU= Received: from fx303 (fx303.security-mail.net [127.0.0.1]) by fx303.security-mail.net (Postfix) with ESMTP id 614DD30F6E7; Tue, 3 Jan 2023 17:44:33 +0100 (CET) Received: from zimbra2.kalray.eu (unknown [217.181.231.53]) by fx303.security-mail.net (Postfix) with ESMTPS id 056DC30F75D; Tue, 3 Jan 2023 17:44:33 +0100 (CET) Received: from zimbra2.kalray.eu (localhost [127.0.0.1]) by zimbra2.kalray.eu (Postfix) with ESMTPS id 92BF527E03FD; Tue, 3 Jan 2023 17:44:32 +0100 (CET) Received: from localhost (localhost [127.0.0.1]) by zimbra2.kalray.eu (Postfix) with ESMTP id 459B427E03F4; Tue, 3 Jan 2023 17:44:32 +0100 (CET) Received: from zimbra2.kalray.eu ([127.0.0.1]) by localhost (zimbra2.kalray.eu [127.0.0.1]) (amavisd-new, port 10026) with ESMTP id Xsg-4X01ox8l; Tue, 3 Jan 2023 17:44:32 +0100 (CET) Received: from junon.lin.mbt.kalray.eu (unknown [192.168.37.161]) by zimbra2.kalray.eu (Postfix) with ESMTPSA id 225FB27E03FD; Tue, 3 Jan 2023 17:44:32 +0100 (CET) X-Virus-Scanned: E-securemail Secumail-id: <71a9.63b45b71.2db8.0> DKIM-Filter: OpenDKIM Filter v2.10.3 zimbra2.kalray.eu 459B427E03F4 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kalray.eu; s=32AE1B44-9502-11E5-BA35-3734643DEF29; t=1672764272; bh=fbOvJkR6P9mNqBrQ80+73d3G551RS8VBLWSjX43k94M=; h=From:To:Date:Message-Id:MIME-Version; b=m87pxQAR/oe8BiN+M8QW85LosmTKkEkP3YzhZHs4Vk+9hApTSbzZUdvtTdVgl9rV/ 0ajLN/DVmwpmj7qiMuja1fKLscV1yb+f2RTDtdtS2YKQZ0PYQA0RehVk89+g1RaaD4 vN5CsR6h9lG7ytkCCeifXMIn+o+ASKOMKpaRc72A= From: Yann Sionneau Cc: Yann Sionneau , Eric Biederman , Kees Cook , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Clement Leger , Julian Vetter , Marius Gligor Subject: [RFC PATCH 14/25] kvx: Add ELF relocations and module support Date: Tue, 3 Jan 2023 17:43:48 +0100 Message-ID: <20230103164359.24347-15-ysionneau@kalray.eu> X-Mailer: git-send-email 2.37.2 In-Reply-To: <20230103164359.24347-1-ysionneau@kalray.eu> References: <20230103164359.24347-1-ysionneau@kalray.eu> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-ALTERMIMEV2_out: done To: unlisted-recipients:; (no To-header on input) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" Add ELF-related definition and module relocation code for basic kvx support. CC: Eric Biederman CC: Kees Cook CC: linux-mm@kvack.org CC: linux-kernel@vger.kernel.org Co-developed-by: Clement Leger Signed-off-by: Clement Leger Co-developed-by: Julian Vetter Signed-off-by: Julian Vetter Co-developed-by: Marius Gligor Signed-off-by: Marius Gligor Co-developed-by: Yann Sionneau Signed-off-by: Yann Sionneau --- arch/kvx/include/asm/elf.h | 155 ++++++++++++++++++++++++++++++++ arch/kvx/include/asm/vermagic.h | 12 +++ arch/kvx/kernel/module.c | 148 ++++++++++++++++++++++++++++++ 3 files changed, 315 insertions(+) create mode 100644 arch/kvx/include/asm/elf.h create mode 100644 arch/kvx/include/asm/vermagic.h create mode 100644 arch/kvx/kernel/module.c diff --git a/arch/kvx/include/asm/elf.h b/arch/kvx/include/asm/elf.h new file mode 100644 index 000000000000..38978d48221e --- /dev/null +++ b/arch/kvx/include/asm/elf.h @@ -0,0 +1,155 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Copyright (C) 2017-2023 Kalray Inc. + * Author(s): Yann Sionneau + * Clement Leger + * Marius Gligor + * Guillaume Thouvenin + */ + +#ifndef _ASM_KVX_ELF_H +#define _ASM_KVX_ELF_H + +#include + +#include + +/* + * These are used to set parameters in the core dumps. + */ +#define ELF_CLASS ELFCLASS64 +#define ELF_DATA ELFDATA2LSB +#define ELF_ARCH EM_KVX + +typedef uint64_t elf_greg_t; +typedef uint64_t elf_fpregset_t; + +#define ELF_NGREG (sizeof(struct user_pt_regs) / sizeof(elf_greg_t)) +typedef elf_greg_t elf_gregset_t[ELF_NGREG]; + +/* Copy user_pt_regs from pt_regs into the elf_gregset_t */ +#define ELF_CORE_COPY_REGS(dest, regs) \ + *(struct user_pt_regs *)&(dest) =3D (regs)->user_regs; + +/* + * This is used to ensure we don't load something for the wrong architectu= re. + */ +#define elf_check_arch(x) ((x)->e_machine =3D=3D EM_KVX) + +#define ELF_CORE_EFLAGS 0x1308 + +#define ELF_EXEC_PAGESIZE (PAGE_SIZE) + +/* + * This is the location that an ET_DYN program is loaded if exec'ed. Typi= cal + * use of this is to invoke "./ld.so someprog" to test out a new version of + * the loader. We need to make sure that it is out of the way of the prog= ram + * that it will "exec", and that there is sufficient room for the brk. + */ +#define ELF_ET_DYN_BASE ((TASK_SIZE / 3) * 2) + +/* + * This yields a mask that user programs can use to figure out what + * instruction set this CPU supports. This could be done in user space, + * but it's not easy, and we've already done it here. + */ +#define ELF_HWCAP (elf_hwcap) +extern unsigned long elf_hwcap; + +/* + * This yields a string that ld.so will use to load implementation + * specific libraries for optimization. This is more specific in + * intent than poking at uname or /proc/cpuinfo. + */ +#define ELF_PLATFORM (NULL) + +#define ARCH_HAS_SETUP_ADDITIONAL_PAGES 1 +struct linux_binprm; +extern int arch_setup_additional_pages(struct linux_binprm *bprm, + int uses_interp); + +/* KVX relocs */ +#define R_KVX_NONE 0 +#define R_KVX_16 1 +#define R_KVX_32 2 +#define R_KVX_64 3 +#define R_KVX_S16_PCREL 4 +#define R_KVX_PCREL17 5 +#define R_KVX_PCREL27 6 +#define R_KVX_32_PCREL 7 +#define R_KVX_S37_PCREL_LO10 8 +#define R_KVX_S37_PCREL_UP27 9 +#define R_KVX_S43_PCREL_LO10 10 +#define R_KVX_S43_PCREL_UP27 11 +#define R_KVX_S43_PCREL_EX6 12 +#define R_KVX_S64_PCREL_LO10 13 +#define R_KVX_S64_PCREL_UP27 14 +#define R_KVX_S64_PCREL_EX27 15 +#define R_KVX_64_PCREL 16 +#define R_KVX_S16 17 +#define R_KVX_S32_LO5 18 +#define R_KVX_S32_UP27 19 +#define R_KVX_S37_LO10 20 +#define R_KVX_S37_UP27 21 +#define R_KVX_S37_GOTOFF_LO10 22 +#define R_KVX_S37_GOTOFF_UP27 23 +#define R_KVX_S43_GOTOFF_LO10 24 +#define R_KVX_S43_GOTOFF_UP27 25 +#define R_KVX_S43_GOTOFF_EX6 26 +#define R_KVX_32_GOTOFF 27 +#define R_KVX_64_GOTOFF 28 +#define R_KVX_32_GOT 29 +#define R_KVX_S37_GOT_LO10 30 +#define R_KVX_S37_GOT_UP27 31 +#define R_KVX_S43_GOT_LO10 32 +#define R_KVX_S43_GOT_UP27 33 +#define R_KVX_S43_GOT_EX6 34 +#define R_KVX_64_GOT 35 +#define R_KVX_GLOB_DAT 36 +#define R_KVX_COPY 37 +#define R_KVX_JMP_SLOT 38 +#define R_KVX_RELATIVE 39 +#define R_KVX_S43_LO10 40 +#define R_KVX_S43_UP27 41 +#define R_KVX_S43_EX6 42 +#define R_KVX_S64_LO10 43 +#define R_KVX_S64_UP27 44 +#define R_KVX_S64_EX27 45 +#define R_KVX_S37_GOTADDR_LO10 46 +#define R_KVX_S37_GOTADDR_UP27 47 +#define R_KVX_S43_GOTADDR_LO10 48 +#define R_KVX_S43_GOTADDR_UP27 49 +#define R_KVX_S43_GOTADDR_EX6 50 +#define R_KVX_S64_GOTADDR_LO10 51 +#define R_KVX_S64_GOTADDR_UP27 52 +#define R_KVX_S64_GOTADDR_EX27 53 +#define R_KVX_64_DTPMOD 54 +#define R_KVX_64_DTPOFF 55 +#define R_KVX_S37_TLS_DTPOFF_LO10 56 +#define R_KVX_S37_TLS_DTPOFF_UP27 57 +#define R_KVX_S43_TLS_DTPOFF_LO10 58 +#define R_KVX_S43_TLS_DTPOFF_UP27 59 +#define R_KVX_S43_TLS_DTPOFF_EX6 60 +#define R_KVX_S37_TLS_GD_LO10 61 +#define R_KVX_S37_TLS_GD_UP27 62 +#define R_KVX_S43_TLS_GD_LO10 63 +#define R_KVX_S43_TLS_GD_UP27 64 +#define R_KVX_S43_TLS_GD_EX6 65 +#define R_KVX_S37_TLS_LD_LO10 66 +#define R_KVX_S37_TLS_LD_UP27 67 +#define R_KVX_S43_TLS_LD_LO10 68 +#define R_KVX_S43_TLS_LD_UP27 69 +#define R_KVX_S43_TLS_LD_EX6 70 +#define R_KVX_64_TPOFF 71 +#define R_KVX_S37_TLS_IE_LO10 72 +#define R_KVX_S37_TLS_IE_UP27 73 +#define R_KVX_S43_TLS_IE_LO10 74 +#define R_KVX_S43_TLS_IE_UP27 75 +#define R_KVX_S43_TLS_IE_EX6 76 +#define R_KVX_S37_TLS_LE_LO10 77 +#define R_KVX_S37_TLS_LE_UP27 78 +#define R_KVX_S43_TLS_LE_LO10 79 +#define R_KVX_S43_TLS_LE_UP27 80 +#define R_KVX_S43_TLS_LE_EX6 81 + +#endif /* _ASM_KVX_ELF_H */ diff --git a/arch/kvx/include/asm/vermagic.h b/arch/kvx/include/asm/vermagi= c.h new file mode 100644 index 000000000000..fef9a33065df --- /dev/null +++ b/arch/kvx/include/asm/vermagic.h @@ -0,0 +1,12 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Copyright (C) 2017-2023 Kalray Inc. + * Author(s): Clement Leger + */ + +#ifndef _ASM_KVX_VERMAGIC_H +#define _ASM_KVX_VERMAGIC_H + +#define MODULE_ARCH_VERMAGIC "kvx" + +#endif /* _ASM_KVX_VERMAGIC_H */ diff --git a/arch/kvx/kernel/module.c b/arch/kvx/kernel/module.c new file mode 100644 index 000000000000..b9383792ae45 --- /dev/null +++ b/arch/kvx/kernel/module.c @@ -0,0 +1,148 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2017-2023 Kalray Inc. + * Author(s): Yann Sionneau + * Clement Leger + */ + +#include +#include +#include + + +static int apply_rela_bits(Elf64_Addr loc, Elf64_Addr val, + int sign, int immsize, int bits, int rshift, + int lshift, unsigned int relocnum, + struct module *me) +{ + unsigned long long umax; + long long min, max; + unsigned long long mask =3D GENMASK_ULL(bits + lshift - 1, lshift); + + if (sign) { + min =3D -(1ULL << (immsize - 1)); + max =3D (1ULL << (immsize - 1)) - 1; + if ((long long) val < min || (long long) val > max) + goto too_big; + val =3D (Elf64_Addr)(((long) val) >> rshift); + } else { + if (immsize < 64) + umax =3D (1ULL << immsize) - 1; + else + umax =3D -1ULL; + if ((unsigned long long) val > umax) + goto too_big; + val >>=3D rshift; + } + + val <<=3D lshift; + val &=3D mask; + if (bits <=3D 32) + *(u32 *) loc =3D (*(u32 *)loc & ~mask) | val; + else + *(u64 *) loc =3D (*(u64 *)loc & ~mask) | val; + + return 0; +too_big: + pr_err("%s: value %llx does not fit in %d bits for reloc %u", + me->name, val, bits, relocnum); + return -ENOEXEC; +} + +int apply_relocate_add(Elf64_Shdr *sechdrs, + const char *strtab, + unsigned int symindex, + unsigned int relsec, + struct module *me) +{ + unsigned int i; + Elf64_Addr loc; + u64 val; + s64 sval; + Elf64_Sym *sym; + Elf64_Rela *rel =3D (void *)sechdrs[relsec].sh_addr; + int ret =3D 0; + + pr_debug("Applying relocate section %u to %u\n", + relsec, sechdrs[relsec].sh_info); + + for (i =3D 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) { + /* This is where to make the change */ + loc =3D (Elf64_Addr)sechdrs[sechdrs[relsec].sh_info].sh_addr + + rel[i].r_offset; + /* This is the symbol it is referring to. Note that all + * undefined symbols have been resolved. + */ + sym =3D (Elf64_Sym *)sechdrs[symindex].sh_addr + + ELF64_R_SYM(rel[i].r_info); + + pr_debug("type %d st_value %llx r_addend %llx loc %llx offset %llx\n", + (int)ELF64_R_TYPE(rel[i].r_info), + sym->st_value, rel[i].r_addend, (uint64_t)loc, + rel[i].r_offset); + + val =3D sym->st_value + rel[i].r_addend; + switch (ELF64_R_TYPE(rel[i].r_info)) { + case R_KVX_NONE: + break; + case R_KVX_32: + ret =3D apply_rela_bits(loc, val, 0, 32, 32, 0, 0, + ELF64_R_TYPE(rel[i].r_info), + me); + break; + case R_KVX_64: + ret =3D apply_rela_bits(loc, val, 0, 64, 64, 0, 0, + ELF64_R_TYPE(rel[i].r_info), + me); + break; + case R_KVX_S43_LO10: + ret =3D apply_rela_bits(loc, val, 1, 43, 10, 0, 6, + ELF64_R_TYPE(rel[i].r_info), + me); + break; + case R_KVX_S64_LO10: + ret =3D apply_rela_bits(loc, val, 1, 64, 10, 0, 6, + ELF64_R_TYPE(rel[i].r_info), + me); + break; + case R_KVX_S43_UP27: + ret =3D apply_rela_bits(loc, val, 1, 43, 27, 10, 0, + ELF64_R_TYPE(rel[i].r_info), + me); + break; + case R_KVX_S64_UP27: + ret =3D apply_rela_bits(loc, val, 1, 64, 27, 10, 0, + ELF64_R_TYPE(rel[i].r_info), + me); + break; + case R_KVX_S43_EX6: + ret =3D apply_rela_bits(loc, val, 1, 43, 6, 37, 0, + ELF64_R_TYPE(rel[i].r_info), + me); + break; + case R_KVX_S64_EX27: + ret =3D apply_rela_bits(loc, val, 1, 64, 27, 37, 0, + ELF64_R_TYPE(rel[i].r_info), + me); + break; + case R_KVX_PCREL27: + if (__builtin_sub_overflow(val, loc, &sval)) { + pr_err("%s: Signed integer overflow, this should not happen\n", + me->name); + return -ENOEXEC; + } + sval >>=3D 2; + ret =3D apply_rela_bits(loc, (Elf64_Addr)sval, 1, 27, 27, + 0, 0, + ELF64_R_TYPE(rel[i].r_info), + me); + break; + default: + pr_err("%s: Unknown relocation: %llu\n", + me->name, ELF64_R_TYPE(rel[i].r_info)); + ret =3D -ENOEXEC; + } + } + return ret; +} + --=20 2.37.2