diff --git a/arch/mips/include/asm/elf.h b/arch/mips/include/asm/elf.h index 891013578490..3dba5d05830c 100644 --- a/arch/mips/include/asm/elf.h +++ b/arch/mips/include/asm/elf.h @@ -12,7 +12,6 @@ #include #include -#include #include /* ELF header e_flags defines. */ @@ -44,6 +43,7 @@ #define EF_MIPS_OPTIONS_FIRST 0x00000080 #define EF_MIPS_32BITMODE 0x00000100 #define EF_MIPS_FP64 0x00000200 +#define EF_MIPS_NAN2008 0x00000400 #define EF_MIPS_ABI 0x0000f000 #define EF_MIPS_ARCH 0xf0000000 @@ -305,7 +305,7 @@ do { \ \ current->thread.abi = &mips_abi; \ \ - current->thread.fpu.fcr31 = boot_cpu_data.fpu_csr31; \ + mips_set_personality_nan(state); \ } while (0) #endif /* CONFIG_32BIT */ @@ -367,7 +367,7 @@ do { \ else \ current->thread.abi = &mips_abi; \ \ - current->thread.fpu.fcr31 = boot_cpu_data.fpu_csr31; \ + mips_set_personality_nan(state); \ \ p = personality(current->personality); \ if (p != PER_LINUX32 && p != PER_LINUX) \ @@ -432,6 +432,7 @@ extern int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp); struct arch_elf_state { + int nan_2008; int fp_abi; int interp_fp_abi; int overall_fp_mode; @@ -440,6 +441,7 @@ struct arch_elf_state { #define MIPS_ABI_FP_UNKNOWN (-1) /* Unknown FP ABI (kernel internal) */ #define INIT_ARCH_ELF_STATE { \ + .nan_2008 = -1, \ .fp_abi = MIPS_ABI_FP_UNKNOWN, \ .interp_fp_abi = MIPS_ABI_FP_UNKNOWN, \ .overall_fp_mode = -1, \ @@ -451,6 +453,7 @@ extern int arch_elf_pt_proc(void *ehdr, void *phdr, struct file *elf, extern int arch_check_elf(void *ehdr, bool has_interpreter, void *interp_ehdr, struct arch_elf_state *state); +extern void mips_set_personality_nan(struct arch_elf_state *state); extern void mips_set_personality_fp(struct arch_elf_state *state); #endif /* _ASM_ELF_H */ diff --git a/arch/mips/kernel/elf.c b/arch/mips/kernel/elf.c index 7d1a90903e4b..f36a261b275c 100644 --- a/arch/mips/kernel/elf.c +++ b/arch/mips/kernel/elf.c @@ -11,6 +11,8 @@ #include #include +#include + /* FPU modes */ enum { FP_FRE, @@ -135,6 +137,10 @@ int arch_check_elf(void *_ehdr, bool has_interpreter, void *_interp_ehdr, struct elf32_hdr e32; struct elf64_hdr e64; } *ehdr = _ehdr; + union { + struct elf32_hdr e32; + struct elf64_hdr e64; + } *iehdr = _interp_ehdr; struct mode_req prog_req, interp_req; int fp_abi, interp_fp_abi, abi0, abi1, max_abi; bool elf32; @@ -143,6 +149,32 @@ int arch_check_elf(void *_ehdr, bool has_interpreter, void *_interp_ehdr, elf32 = ehdr->e32.e_ident[EI_CLASS] == ELFCLASS32; flags = elf32 ? ehdr->e32.e_flags : ehdr->e64.e_flags; + /* + * Determine the NaN personality, reject the binary if no hardware + * support. Also ensure that any interpreter matches the executable. + */ + if (flags & EF_MIPS_NAN2008) { + if (cpu_has_nan_2008) + state->nan_2008 = 1; + else + return -ENOEXEC; + } else { + if (cpu_has_nan_legacy) + state->nan_2008 = 0; + else + return -ENOEXEC; + } + if (has_interpreter) { + bool ielf32; + u32 iflags; + + ielf32 = iehdr->e32.e_ident[EI_CLASS] == ELFCLASS32; + iflags = ielf32 ? iehdr->e32.e_flags : iehdr->e64.e_flags; + + if ((flags ^ iflags) & EF_MIPS_NAN2008) + return -ELIBBAD; + } + if (!config_enabled(CONFIG_MIPS_O32_FP64_SUPPORT)) return 0; @@ -266,3 +298,27 @@ void mips_set_personality_fp(struct arch_elf_state *state) BUG(); } } + +/* + * Select the IEEE 754 NaN encoding and ABS.fmt/NEG.fmt execution mode + * in FCSR according to the ELF NaN personality. + */ +void mips_set_personality_nan(struct arch_elf_state *state) +{ + struct cpuinfo_mips *c = &boot_cpu_data; + struct task_struct *t = current; + + t->thread.fpu.fcr31 = c->fpu_csr31; + switch (state->nan_2008) { + case 0: + break; + case 1: + if (!(c->fpu_msk31 & FPU_CSR_NAN2008)) + t->thread.fpu.fcr31 |= FPU_CSR_NAN2008; + if (!(c->fpu_msk31 & FPU_CSR_ABS2008)) + t->thread.fpu.fcr31 |= FPU_CSR_ABS2008; + break; + default: + BUG(); + } +}