diff options
Diffstat (limited to 'arch/mips/kernel/elf.c')
| -rw-r--r-- | arch/mips/kernel/elf.c | 102 |
1 files changed, 87 insertions, 15 deletions
diff --git a/arch/mips/kernel/elf.c b/arch/mips/kernel/elf.c index 4a4d9e067c89..c3c234dc0c07 100644 --- a/arch/mips/kernel/elf.c +++ b/arch/mips/kernel/elf.c @@ -11,6 +11,12 @@ #include <linux/elf.h> #include <linux/sched.h> +#include <asm/cpu-info.h> + +/* Whether to accept legacy-NaN and 2008-NaN user binaries. */ +bool mips_use_nan_legacy; +bool mips_use_nan_2008; + /* FPU modes */ enum { FP_FRE, @@ -68,15 +74,23 @@ static struct mode_req none_req = { true, true, false, true, true }; int arch_elf_pt_proc(void *_ehdr, void *_phdr, struct file *elf, bool is_interp, struct arch_elf_state *state) { - struct elf32_hdr *ehdr32 = _ehdr; + union { + struct elf32_hdr e32; + struct elf64_hdr e64; + } *ehdr = _ehdr; struct elf32_phdr *phdr32 = _phdr; struct elf64_phdr *phdr64 = _phdr; struct mips_elf_abiflags_v0 abiflags; + bool elf32; + u32 flags; int ret; + elf32 = ehdr->e32.e_ident[EI_CLASS] == ELFCLASS32; + flags = elf32 ? ehdr->e32.e_flags : ehdr->e64.e_flags; + /* Lets see if this is an O32 ELF */ - if (ehdr32->e_ident[EI_CLASS] == ELFCLASS32) { - if (ehdr32->e_flags & EF_MIPS_FP64) { + if (elf32) { + if (flags & EF_MIPS_FP64) { /* * Set MIPS_ABI_FP_OLD_64 for EF_MIPS_FP64. We will override it * later if needed @@ -120,13 +134,50 @@ int arch_elf_pt_proc(void *_ehdr, void *_phdr, struct file *elf, return 0; } -int arch_check_elf(void *_ehdr, bool has_interpreter, +int arch_check_elf(void *_ehdr, bool has_interpreter, void *_interp_ehdr, struct arch_elf_state *state) { - struct elf32_hdr *ehdr = _ehdr; + union { + 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 is_mips64; + bool elf32; + u32 flags; + + 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 not allowed. + * Also ensure that any interpreter matches the executable. + */ + if (flags & EF_MIPS_NAN2008) { + if (mips_use_nan_2008) + state->nan_2008 = 1; + else + return -ENOEXEC; + } else { + if (mips_use_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; @@ -142,21 +193,18 @@ int arch_check_elf(void *_ehdr, bool has_interpreter, abi0 = abi1 = fp_abi; } - is_mips64 = (ehdr->e_ident[EI_CLASS] == ELFCLASS64) || - (ehdr->e_flags & EF_MIPS_ABI2); + if (elf32 && !(flags & EF_MIPS_ABI2)) { + /* Default to a mode capable of running code expecting FR=0 */ + state->overall_fp_mode = cpu_has_mips_r6 ? FP_FRE : FP_FR0; - if (is_mips64) { + /* Allow all ABIs we know about */ + max_abi = MIPS_ABI_FP_64A; + } else { /* MIPS64 code always uses FR=1, thus the default is easy */ state->overall_fp_mode = FP_FR1; /* Disallow access to the various FPXX & FP64 ABIs */ max_abi = MIPS_ABI_FP_SOFT; - } else { - /* Default to a mode capable of running code expecting FR=0 */ - state->overall_fp_mode = cpu_has_mips_r6 ? FP_FRE : FP_FR0; - - /* Allow all ABIs we know about */ - max_abi = MIPS_ABI_FP_64A; } if ((abi0 > max_abi && abi0 != MIPS_ABI_FP_UNKNOWN) || @@ -254,3 +302,27 @@ 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(); + } +} |