Commit-ID: b40a142b12b5c4312171140ff2bc92971b8a7a09 Gitweb: https://git.kernel.org/tip/b40a142b12b5c4312171140ff2bc92971b8a7a09 Author: Ard Biesheuvel <ard.biesheu...@linaro.org> AuthorDate: Tue, 18 Sep 2018 23:51:39 -0700 Committer: Thomas Gleixner <t...@linutronix.de> CommitDate: Thu, 27 Sep 2018 17:56:47 +0200
x86: Add support for 64-bit place relative relocations Add support for R_X86_64_PC64 relocations, which operate on 64-bit quantities holding a relative symbol reference. Also remove the definition of R_X86_64_NUM: given that it is currently unused, it is unclear what the new value should be. Signed-off-by: Ard Biesheuvel <ard.biesheu...@linaro.org> Signed-off-by: Thomas Gleixner <t...@linutronix.de> Acked-by: Peter Zijlstra (Intel) <pet...@infradead.org> Cc: linux-arm-ker...@lists.infradead.org Cc: linux-s...@vger.kernel.org Cc: Arnd Bergmann <a...@arndb.de> Cc: Heiko Carstens <heiko.carst...@de.ibm.com> Cc: Kees Cook <keesc...@chromium.org> Cc: Will Deacon <will.dea...@arm.com> Cc: Catalin Marinas <catalin.mari...@arm.com> Cc: Steven Rostedt <rost...@goodmis.org> Cc: Martin Schwidefsky <schwidef...@de.ibm.com> Cc: Jessica Yu <j...@kernel.org> Link: https://lkml.kernel.org/r/20180919065144.25010-5-ard.biesheu...@linaro.org --- arch/x86/include/asm/elf.h | 3 +-- arch/x86/kernel/module.c | 6 ++++++ arch/x86/tools/relocs.c | 10 ++++++++++ arch/x86/um/asm/elf.h | 3 +-- 4 files changed, 18 insertions(+), 4 deletions(-) diff --git a/arch/x86/include/asm/elf.h b/arch/x86/include/asm/elf.h index 0d157d2a1e2a..a357031d85b5 100644 --- a/arch/x86/include/asm/elf.h +++ b/arch/x86/include/asm/elf.h @@ -62,8 +62,7 @@ typedef struct user_fxsr_struct elf_fpxregset_t; #define R_X86_64_PC16 13 /* 16 bit sign extended pc relative */ #define R_X86_64_8 14 /* Direct 8 bit sign extended */ #define R_X86_64_PC8 15 /* 8 bit sign extended pc relative */ - -#define R_X86_64_NUM 16 +#define R_X86_64_PC64 24 /* Place relative 64-bit signed */ /* * These are used to set parameters in the core dumps. diff --git a/arch/x86/kernel/module.c b/arch/x86/kernel/module.c index f58336af095c..b052e883dd8c 100644 --- a/arch/x86/kernel/module.c +++ b/arch/x86/kernel/module.c @@ -201,6 +201,12 @@ int apply_relocate_add(Elf64_Shdr *sechdrs, goto overflow; #endif break; + case R_X86_64_PC64: + if (*(u64 *)loc != 0) + goto invalid_relocation; + val -= (u64)loc; + *(u64 *)loc = val; + break; default: pr_err("%s: Unknown rela relocation: %llu\n", me->name, ELF64_R_TYPE(rel[i].r_info)); diff --git a/arch/x86/tools/relocs.c b/arch/x86/tools/relocs.c index 3a6c8ebc8032..0b08067c45f3 100644 --- a/arch/x86/tools/relocs.c +++ b/arch/x86/tools/relocs.c @@ -196,6 +196,7 @@ static const char *rel_type(unsigned type) #if ELF_BITS == 64 REL_TYPE(R_X86_64_NONE), REL_TYPE(R_X86_64_64), + REL_TYPE(R_X86_64_PC64), REL_TYPE(R_X86_64_PC32), REL_TYPE(R_X86_64_GOT32), REL_TYPE(R_X86_64_PLT32), @@ -782,6 +783,15 @@ static int do_reloc64(struct section *sec, Elf_Rel *rel, ElfW(Sym) *sym, add_reloc(&relocs32neg, offset); break; + case R_X86_64_PC64: + /* + * Only used by jump labels + */ + if (is_percpu_sym(sym, symname)) + die("Invalid R_X86_64_PC64 relocation against per-CPU symbol %s\n", + symname); + break; + case R_X86_64_32: case R_X86_64_32S: case R_X86_64_64: diff --git a/arch/x86/um/asm/elf.h b/arch/x86/um/asm/elf.h index 548197212a45..413f3519d9a1 100644 --- a/arch/x86/um/asm/elf.h +++ b/arch/x86/um/asm/elf.h @@ -116,8 +116,7 @@ do { \ #define R_X86_64_PC16 13 /* 16 bit sign extended pc relative */ #define R_X86_64_8 14 /* Direct 8 bit sign extended */ #define R_X86_64_PC8 15 /* 8 bit sign extended pc relative */ - -#define R_X86_64_NUM 16 +#define R_X86_64_PC64 24 /* Place relative 64-bit signed */ /* * This is used to ensure we don't load something for the wrong architecture.
