// SPDX-License-Identifier: GPL-2.0-only/* * linux/fs/binfmt_elf.c * * These are the functions used to load ELF format executables as used * on SVr4 machines. Information on the format may be found in the book * "UNIX SYSTEM V RELEASE 4 Programmers Guide: Ansi C and Programming Support * Tools". * * Copyright 1993, 1994: Eric Youngdale (ericy@cais.com). */ #include <linux/module.h>#include <linux/kernel.h>#include <linux/fs.h>#include <linux/log2.h>#include <linux/mm.h>#include <linux/mman.h>#include <linux/errno.h>#include <linux/signal.h>#include <linux/binfmts.h>#include <linux/string.h>#include <linux/file.h>#include <linux/slab.h>#include <linux/personality.h>#include <linux/elfcore.h>#include <linux/init.h>#include <linux/highuid.h>#include <linux/compiler.h>#include <linux/highmem.h>#include <linux/hugetlb.h>#include <linux/pagemap.h>#include <linux/vmalloc.h>#include <linux/security.h>#include <linux/random.h>#include <linux/elf.h>#include <linux/elf-randomize.h>#include <linux/utsname.h>#include <linux/coredump.h>#include <linux/sched.h>#include <linux/sched/coredump.h>#include <linux/sched/task_stack.h>#include <linux/sched/cputime.h>#include <linux/sizes.h>#include <linux/types.h>#include <linux/cred.h>#include <linux/dax.h>#include <linux/uaccess.h>#include <uapi/linux/rseq.h>#include <linux/rseq.h>#include <asm/param.h>#include <asm/page.h> #ifndef ELF_COMPAT#define ELF_COMPAT 0#endif #ifndef user_long_t#define user_long_t long#endif#ifndef user_siginfo_t#define user_siginfo_t siginfo_t#endif /* That's for binfmt_elf_fdpic to deal with */#ifndef elf_check_fdpic#define elf_check_fdpic(ex) false#endif static int load_elf_binary(struct linux_binprm *bprm); /* * If we don't support core dumping, then supply a NULL so we * don't even try. */#ifdef CONFIG_ELF_COREstatic int elf_core_dump(struct coredump_params *cprm);#else#define elf_core_dump NULL#endif #if ELF_EXEC_PAGESIZE > PAGE_SIZE#define ELF_MIN_ALIGN ELF_EXEC_PAGESIZE#else#define ELF_MIN_ALIGN PAGE_SIZE#endif #ifndef ELF_CORE_EFLAGS#define ELF_CORE_EFLAGS 0#endif #define ELF_PAGESTART(_v) ((_v) & ~(int)(ELF_MIN_ALIGN-1))#define ELF_PAGEOFFSET(_v) ((_v) & (ELF_MIN_ALIGN-1))#define ELF_PAGEALIGN(_v) (((_v) + ELF_MIN_ALIGN - 1) & ~(ELF_MIN_ALIGN - 1)) static struct linux_binfmt elf_format = { .module = THIS_MODULE, .load_binary = load_elf_binary,#ifdef CONFIG_COREDUMP .core_dump = elf_core_dump, .min_coredump = ELF_EXEC_PAGESIZE,#endif}; #define BAD_ADDR(x) (unlikely((unsigned long)(x) >= TASK_SIZE)) static inline void elf_coredump_set_mm_eflags(struct mm_struct *mm, u32 flags){#ifdef CONFIG_ARCH_HAS_ELF_CORE_EFLAGS mm->saved_e_flags = flags;#endif} static inline u32 elf_coredump_get_mm_eflags(struct mm_struct *mm, u32 flags){#ifdef CONFIG_ARCH_HAS_ELF_CORE_EFLAGS flags = mm->saved_e_flags;#endif return flags;} /* * We need to explicitly zero any trailing portion of the page that follows * p_filesz when it ends before the page ends (e.g. bss), otherwise this * memory will contain the junk from the file that should not be present. */static int padzero(unsigned long address){ unsigned long nbyte; nbyte = ELF_PAGEOFFSET(address); if (nbyte) { nbyte = ELF_MIN_ALIGN - nbyte; if (clear_user((void __user *)address, nbyte)) return -EFAULT; } return 0;} /* Let's use some macros to make this stack manipulation a little clearer */#ifdef CONFIG_STACK_GROWSUP#define STACK_ADD(sp, items) ((elf_addr_t __user *)(sp) + (items))#define STACK_ROUND(sp, items) \ ((15 + (unsigned long) ((sp) + (items))) &~ 15UL)#define STACK_ALLOC(sp, len) ({ \ elf_addr_t __user *old_sp = (elf_addr_t __user *)sp; sp += len; \ old_sp; })#else#define STACK_ADD(sp, items) ((elf_addr_t __user *)(sp) - (items))#define STACK_ROUND(sp, items) \ (((unsigned long) (sp - items)) &~ 15UL)#define STACK_ALLOC(sp, len) (sp -= len)#endif #ifndef ELF_BASE_PLATFORM/* * AT_BASE_PLATFORM indicates the "real" hardware/microarchitecture. * If the arch defines ELF_BASE_PLATFORM (in asm/elf.h), the value * will be copied to the user stack in the same manner as AT_PLATFORM. */#define ELF_BASE_PLATFORM NULL#endif static intcreate_elf_tables(struct linux_binprm *bprm, const struct elfhdr *exec, unsigned long interp_load_addr, unsigned long e_entry, unsigned long phdr_addr){ struct mm_struct *mm = current->mm; unsigned long p = bprm->p; int argc = bprm->argc; int envc = bprm->envc; elf_addr_t __user *sp; elf_addr_t __user *u_platform; elf_addr_t __user *u_base_platform; elf_addr_t __user *u_rand_bytes; const char *k_platform = ELF_PLATFORM; const char *k_base_platform = ELF_BASE_PLATFORM; unsigned char k_rand_bytes[16]; int items; elf_addr_t *elf_info; int ei_index; const struct cred *cred = current_cred(); struct vm_area_struct *vma; /* * In some cases (e.g. Hyper-Threading), we want to avoid L1 * evictions by the processes running on the same package. One * thing we can do is to shuffle the initial stack for them. */ p = arch_align_stack(p); /* * If this architecture has a platform capability string, copy it * to userspace. In some cases (Sparc), this info is impossible * for userspace to get any other way, in others (i386) it is * merely difficult. */ u_platform = NULL; if (k_platform) { size_t len = strlen(k_platform) + 1; u_platform = (elf_addr_t __user *)STACK_ALLOC(p, len); if (copy_to_user(u_platform, k_platform, len)) return -EFAULT; } /* * If this architecture has a "base" platform capability * string, copy it to userspace. */ u_base_platform = NULL; if (k_base_platform) { size_t len = strlen(k_base_platform) + 1; u_base_platform = (elf_addr_t __user *)STACK_ALLOC(p, len); if (copy_to_user(u_base_platform, k_base_platform, len)) return -EFAULT; } /* * Generate 16 random bytes for userspace PRNG seeding. */ get_random_bytes(k_rand_bytes, sizeof(k_rand_bytes)); u_rand_bytes = (elf_addr_t __user *) STACK_ALLOC(p, sizeof(k_rand_bytes)); if (copy_to_user(u_rand_bytes, k_rand_bytes, sizeof(k_rand_bytes))) return -EFAULT; /* Create the ELF interpreter info */ elf_info = (elf_addr_t *)mm->saved_auxv; /* update AT_VECTOR_SIZE_BASE if the number of NEW_AUX_ENT() changes */#define NEW_AUX_ENT(id, val) \ do { \ *elf_info++ = id; \ *elf_info++ = val; \ } while (0) #ifdef ARCH_DLINFO /* * ARCH_DLINFO must come first so PPC can do its special alignment of * AUXV. * update AT_VECTOR_SIZE_ARCH if the number of NEW_AUX_ENT() in * ARCH_DLINFO changes */ ARCH_DLINFO;#endif NEW_AUX_ENT(AT_HWCAP, ELF_HWCAP); NEW_AUX_ENT(AT_PAGESZ, ELF_EXEC_PAGESIZE); NEW_AUX_ENT(AT_CLKTCK, CLOCKS_PER_SEC); NEW_AUX_ENT(AT_PHDR, phdr_addr); NEW_AUX_ENT(AT_PHENT, sizeof(struct elf_phdr)); NEW_AUX_ENT(AT_PHNUM, exec->e_phnum); NEW_AUX_ENT(AT_BASE, interp_load_addr); NEW_AUX_ENT(AT_FLAGS, bprm_at_flags(bprm)); NEW_AUX_ENT(AT_ENTRY, e_entry); NEW_AUX_ENT(AT_UID, from_kuid_munged(cred->user_ns, cred->uid)); NEW_AUX_ENT(AT_EUID, from_kuid_munged(cred->user_ns, cred->euid)); NEW_AUX_ENT(AT_GID, from_kgid_munged(cred->user_ns, cred->gid)); NEW_AUX_ENT(AT_EGID, from_kgid_munged(cred->user_ns, cred->egid)); NEW_AUX_ENT(AT_SECURE, bprm->secureexec); NEW_AUX_ENT(AT_RANDOM, (elf_addr_t)(unsigned long)u_rand_bytes);#ifdef ELF_HWCAP2 NEW_AUX_ENT(AT_HWCAP2, ELF_HWCAP2);#endif#ifdef ELF_HWCAP3 NEW_AUX_ENT(AT_HWCAP3, ELF_HWCAP3);#endif#ifdef ELF_HWCAP4 NEW_AUX_ENT(AT_HWCAP4, ELF_HWCAP4);#endif NEW_AUX_ENT(AT_EXECFN, bprm->exec); if (k_platform) { NEW_AUX_ENT(AT_PLATFORM, (elf_addr_t)(unsigned long)u_platform); } if (k_base_platform) { NEW_AUX_ENT(AT_BASE_PLATFORM, (elf_addr_t)(unsigned long)u_base_platform); } if (bprm->have_execfd) { NEW_AUX_ENT(AT_EXECFD, bprm->execfd); }#ifdef CONFIG_RSEQ NEW_AUX_ENT(AT_RSEQ_FEATURE_SIZE, offsetof(struct rseq, end)); NEW_AUX_ENT(AT_RSEQ_ALIGN, rseq_alloc_align());#endif#undef NEW_AUX_ENT /* AT_NULL is zero; clear the rest too */ memset(elf_info, 0, (char *)mm->saved_auxv + sizeof(mm->saved_auxv) - (char *)elf_info); /* And advance past the AT_NULL entry. */ elf_info += 2; ei_index = elf_info - (elf_addr_t *)mm->saved_auxv; sp = STACK_ADD(p, ei_index); items = (argc + 1) + (envc + 1) + 1; bprm->p = STACK_ROUND(sp, items); /* Point sp at the lowest address on the stack */#ifdef CONFIG_STACK_GROWSUP sp = (elf_addr_t __user *)bprm->p - items - ei_index; bprm->exec = (unsigned long)sp; /* XXX: PARISC HACK */#else sp = (elf_addr_t __user *)bprm->p;#endif /* * Grow the stack manually; some architectures have a limit on how * far ahead a user-space access may be in order to grow the stack. */ if (mmap_write_lock_killable(mm)) return -EINTR; vma = find_extend_vma_locked(mm, bprm->p); mmap_write_unlock(mm); if (!vma) return -EFAULT; /* Now, let's put argc (and argv, envp if appropriate) on the stack */ if (put_user(argc, sp++)) return -EFAULT; /* Populate list of argv pointers back to argv strings. */ p = mm->arg_end = mm->arg_start; while (argc-- > 0) { size_t len; if (put_user((elf_addr_t)p, sp++)) return -EFAULT; len = strnlen_user((void __user *)p, MAX_ARG_STRLEN); if (!len || len > MAX_ARG_STRLEN) return -EINVAL; p += len; } if (put_user(0, sp++)) return -EFAULT; mm->arg_end = p; /* Populate list of envp pointers back to envp strings. */ mm->env_end = mm->env_start = p; while (envc-- > 0) { size_t len; if (put_user((elf_addr_t)p, sp++)) return -EFAULT; len = strnlen_user((void __user *)p, MAX_ARG_STRLEN); if (!len || len > MAX_ARG_STRLEN) return -EINVAL; p += len; } if (put_user(0, sp++)) return -EFAULT; mm->env_end = p; /* Put the elf_info on the stack in the right place. */ if (copy_to_user(sp, mm->saved_auxv, ei_index * sizeof(elf_addr_t))) return -EFAULT; return 0;} /* * Map "eppnt->p_filesz" bytes from "filep" offset "eppnt->p_offset" * into memory at "addr". (Note that p_filesz is rounded up to the * next page, so any extra bytes from the file must be wiped.) */static unsigned long elf_map(struct file *filep, unsigned long addr, const struct elf_phdr *eppnt, int prot, int type, unsigned long total_size){ unsigned long map_addr; unsigned long size = eppnt->p_filesz + ELF_PAGEOFFSET(eppnt->p_vaddr); unsigned long off = eppnt->p_offset - ELF_PAGEOFFSET(eppnt->p_vaddr); addr = ELF_PAGESTART(addr); size = ELF_PAGEALIGN(size); /* mmap() will return -EINVAL if given a zero size, but a * segment with zero filesize is perfectly valid */ if (!size) return addr; /* * total_size is the size of the ELF (interpreter) image. * The _first_ mmap needs to know the full size, otherwise * randomization might put this image into an overlapping * position with the ELF binary image. (since size < total_size) * So we first map the 'big' image - and unmap the remainder at * the end. (which unmap is needed for ELF images with holes.) */ if (total_size) { total_size = ELF_PAGEALIGN(total_size); map_addr = vm_mmap(filep, addr, total_size, prot, type, off); if (!BAD_ADDR(map_addr)) vm_munmap(map_addr+size, total_size-size); } else map_addr = vm_mmap(filep, addr, size, prot, type, off); if ((type & MAP_FIXED_NOREPLACE) && PTR_ERR((void *)map_addr) == -EEXIST) pr_info("%d (%s): Uhuuh, elf segment at %px requested but the memory is mapped already\n", task_pid_nr(current), current->comm, (void *)addr); return(map_addr);} /* * Map "eppnt->p_filesz" bytes from "filep" offset "eppnt->p_offset" * into memory at "addr". Memory from "p_filesz" through "p_memsz" * rounded up to the next page is zeroed. */static unsigned long elf_load(struct file *filep, unsigned long addr, const struct elf_phdr *eppnt, int prot, int type, unsigned long total_size){ unsigned long zero_start, zero_end; unsigned long map_addr; if (eppnt->p_filesz) { map_addr = elf_map(filep, addr, eppnt, prot, type, total_size); if (BAD_ADDR(map_addr)) return map_addr; if (eppnt->p_memsz > eppnt->p_filesz) { zero_start = map_addr + ELF_PAGEOFFSET(eppnt->p_vaddr) + eppnt->p_filesz; zero_end = map_addr + ELF_PAGEOFFSET(eppnt->p_vaddr) + eppnt->p_memsz; /* * Zero the end of the last mapped page but ignore * any errors if the segment isn't writable. */ if (padzero(zero_start) && (prot & PROT_WRITE)) return -EFAULT; } } else { map_addr = zero_start = ELF_PAGESTART(addr); zero_end = zero_start + ELF_PAGEOFFSET(eppnt->p_vaddr) + eppnt->p_memsz; } if (eppnt->p_memsz > eppnt->p_filesz) { /* * Map the last of the segment. * If the header is requesting these pages to be * executable, honour that (ppc32 needs this). */ int error; zero_start = ELF_PAGEALIGN(zero_start); zero_end = ELF_PAGEALIGN(zero_end); error = vm_brk_flags(zero_start, zero_end - zero_start, prot & PROT_EXEC); if (error) map_addr = error; } return map_addr;} static unsigned long total_mapping_size(const struct elf_phdr *phdr, int nr){ elf_addr_t min_addr = -1; elf_addr_t max_addr = 0; bool pt_load = false; int i; for (i = 0; i < nr; i++) { if (phdr[i].p_type == PT_LOAD) { min_addr = min(min_addr, ELF_PAGESTART(phdr[i].p_vaddr)); max_addr = max(max_addr, phdr[i].p_vaddr + phdr[i].p_memsz); pt_load = true; } } return pt_load ? (max_addr - min_addr) : 0;} static int elf_read(struct file *file, void *buf, size_t len, loff_t pos){ ssize_t rv; rv = kernel_read(file, buf, len, &pos); if (unlikely(rv != len)) { return (rv < 0) ? rv : -EIO; } return 0;} static unsigned long maximum_alignment(struct elf_phdr *cmds, int nr){ unsigned long alignment = 0; int i; for (i = 0; i < nr; i++) { if (cmds[i].p_type == PT_LOAD) { unsigned long p_align = cmds[i].p_align; /* skip non-power of two alignments as invalid */ if (!is_power_of_2(p_align)) continue; alignment = max(alignment, p_align);Lines 1–500 of 2144. Load more
// SPDX-License-Identifier: GPL-2.0-only /* * linux/fs/binfmt_elf.c * * These are the functions used to load ELF format executables as used * on SVr4 machines. Information on the format may be found in the book * "UNIX SYSTEM V RELEASE 4 Programmers Guide: Ansi C and Programming Support * Tools". * * Copyright 1993, 1994: Eric Youngdale (ericy@cais.com). */ #include <linux/module.h> #include <linux/kernel.h> #include <linux/fs.h> #include <linux/log2.h> #include <linux/mm.h> #include <linux/mman.h> #include <linux/errno.h> #include <linux/signal.h> #include <linux/binfmts.h> #include <linux/string.h> #include <linux/file.h> #include <linux/slab.h> #include <linux/personality.h> #include <linux/elfcore.h> #include <linux/init.h> #include <linux/highuid.h> #include <linux/compiler.h> #include <linux/highmem.h> #include <linux/hugetlb.h> #include <linux/pagemap.h> #include <linux/vmalloc.h> #include <linux/security.h> #include <linux/random.h> #include <linux/elf.h> #include <linux/elf-randomize.h> #include <linux/utsname.h> #include <linux/coredump.h> #include <linux/sched.h> #include <linux/sched/coredump.h> #include <linux/sched/task_stack.h> #include <linux/sched/cputime.h> #include <linux/sizes.h> #include <linux/types.h> #include <linux/cred.h> #include <linux/dax.h> #include <linux/uaccess.h> #include <uapi/linux/rseq.h> #include <linux/rseq.h> #include <asm/param.h> #include <asm/page.h> #ifndef ELF_COMPAT #define ELF_COMPAT 0 #endif #ifndef user_long_t #define user_long_t long #endif #ifndef user_siginfo_t #define user_siginfo_t siginfo_t #endif /* That's for binfmt_elf_fdpic to deal with */ #ifndef elf_check_fdpic #define elf_check_fdpic(ex) false #endif static int load_elf_binary(struct linux_binprm *bprm); /* * If we don't support core dumping, then supply a NULL so we * don't even try. */ #ifdef CONFIG_ELF_CORE static int elf_core_dump(struct coredump_params *cprm); #else #define elf_core_dump NULL #endif #if ELF_EXEC_PAGESIZE > PAGE_SIZE #define ELF_MIN_ALIGN ELF_EXEC_PAGESIZE #else #define ELF_MIN_ALIGN PAGE_SIZE #endif #ifndef ELF_CORE_EFLAGS #define ELF_CORE_EFLAGS 0 #endif #define ELF_PAGESTART(_v) ((_v) & ~(int)(ELF_MIN_ALIGN-1)) #define ELF_PAGEOFFSET(_v) ((_v) & (ELF_MIN_ALIGN-1)) #define ELF_PAGEALIGN(_v) (((_v) + ELF_MIN_ALIGN - 1) & ~(ELF_MIN_ALIGN - 1)) static struct linux_binfmt elf_format = { .module = THIS_MODULE, .load_binary = load_elf_binary, #ifdef CONFIG_COREDUMP .core_dump = elf_core_dump, .min_coredump = ELF_EXEC_PAGESIZE, #endif }; #define BAD_ADDR(x) (unlikely((unsigned long)(x) >= TASK_SIZE)) static inline void elf_coredump_set_mm_eflags(struct mm_struct *mm, u32 flags) { #ifdef CONFIG_ARCH_HAS_ELF_CORE_EFLAGS mm->saved_e_flags = flags; #endif } static inline u32 elf_coredump_get_mm_eflags(struct mm_struct *mm, u32 flags) { #ifdef CONFIG_ARCH_HAS_ELF_CORE_EFLAGS flags = mm->saved_e_flags; #endif return flags; } /* * We need to explicitly zero any trailing portion of the page that follows * p_filesz when it ends before the page ends (e.g. bss), otherwise this * memory will contain the junk from the file that should not be present. */ static int padzero(unsigned long address) { unsigned long nbyte; nbyte = ELF_PAGEOFFSET(address); if (nbyte) { nbyte = ELF_MIN_ALIGN - nbyte; if (clear_user((void __user *)address, nbyte)) return -EFAULT; } return 0; } /* Let's use some macros to make this stack manipulation a little clearer */ #ifdef CONFIG_STACK_GROWSUP #define STACK_ADD(sp, items) ((elf_addr_t __user *)(sp) + (items)) #define STACK_ROUND(sp, items) \ ((15 + (unsigned long) ((sp) + (items))) &~ 15UL) #define STACK_ALLOC(sp, len) ({ \ elf_addr_t __user *old_sp = (elf_addr_t __user *)sp; sp += len; \ old_sp; }) #else #define STACK_ADD(sp, items) ((elf_addr_t __user *)(sp) - (items)) #define STACK_ROUND(sp, items) \ (((unsigned long) (sp - items)) &~ 15UL) #define STACK_ALLOC(sp, len) (sp -= len) #endif #ifndef ELF_BASE_PLATFORM /* * AT_BASE_PLATFORM indicates the "real" hardware/microarchitecture. * If the arch defines ELF_BASE_PLATFORM (in asm/elf.h), the value * will be copied to the user stack in the same manner as AT_PLATFORM. */ #define ELF_BASE_PLATFORM NULL #endif static int create_elf_tables(struct linux_binprm *bprm, const struct elfhdr *exec, unsigned long interp_load_addr, unsigned long e_entry, unsigned long phdr_addr) { struct mm_struct *mm = current->mm; unsigned long p = bprm->p; int argc = bprm->argc; int envc = bprm->envc; elf_addr_t __user *sp; elf_addr_t __user *u_platform; elf_addr_t __user *u_base_platform; elf_addr_t __user *u_rand_bytes; const char *k_platform = ELF_PLATFORM; const char *k_base_platform = ELF_BASE_PLATFORM; unsigned char k_rand_bytes[16]; int items; elf_addr_t *elf_info; int ei_index; const struct cred *cred = current_cred(); struct vm_area_struct *vma; /* * In some cases (e.g. Hyper-Threading), we want to avoid L1 * evictions by the processes running on the same package. One * thing we can do is to shuffle the initial stack for them. */ p = arch_align_stack(p); /* * If this architecture has a platform capability string, copy it * to userspace. In some cases (Sparc), this info is impossible * for userspace to get any other way, in others (i386) it is * merely difficult. */ u_platform = NULL; if (k_platform) { size_t len = strlen(k_platform) + 1; u_platform = (elf_addr_t __user *)STACK_ALLOC(p, len); if (copy_to_user(u_platform, k_platform, len)) return -EFAULT; } /* * If this architecture has a "base" platform capability * string, copy it to userspace. */ u_base_platform = NULL; if (k_base_platform) { size_t len = strlen(k_base_platform) + 1; u_base_platform = (elf_addr_t __user *)STACK_ALLOC(p, len); if (copy_to_user(u_base_platform, k_base_platform, len)) return -EFAULT; } /* * Generate 16 random bytes for userspace PRNG seeding. */ get_random_bytes(k_rand_bytes, sizeof(k_rand_bytes)); u_rand_bytes = (elf_addr_t __user *) STACK_ALLOC(p, sizeof(k_rand_bytes)); if (copy_to_user(u_rand_bytes, k_rand_bytes, sizeof(k_rand_bytes))) return -EFAULT; /* Create the ELF interpreter info */ elf_info = (elf_addr_t *)mm->saved_auxv; /* update AT_VECTOR_SIZE_BASE if the number of NEW_AUX_ENT() changes */ #define NEW_AUX_ENT(id, val) \ do { \ *elf_info++ = id; \ *elf_info++ = val; \ } while (0) #ifdef ARCH_DLINFO /* * ARCH_DLINFO must come first so PPC can do its special alignment of * AUXV. * update AT_VECTOR_SIZE_ARCH if the number of NEW_AUX_ENT() in * ARCH_DLINFO changes */ ARCH_DLINFO; #endif NEW_AUX_ENT(AT_HWCAP, ELF_HWCAP); NEW_AUX_ENT(AT_PAGESZ, ELF_EXEC_PAGESIZE); NEW_AUX_ENT(AT_CLKTCK, CLOCKS_PER_SEC); NEW_AUX_ENT(AT_PHDR, phdr_addr); NEW_AUX_ENT(AT_PHENT, sizeof(struct elf_phdr)); NEW_AUX_ENT(AT_PHNUM, exec->e_phnum); NEW_AUX_ENT(AT_BASE, interp_load_addr); NEW_AUX_ENT(AT_FLAGS, bprm_at_flags(bprm)); NEW_AUX_ENT(AT_ENTRY, e_entry); NEW_AUX_ENT(AT_UID, from_kuid_munged(cred->user_ns, cred->uid)); NEW_AUX_ENT(AT_EUID, from_kuid_munged(cred->user_ns, cred->euid)); NEW_AUX_ENT(AT_GID, from_kgid_munged(cred->user_ns, cred->gid)); NEW_AUX_ENT(AT_EGID, from_kgid_munged(cred->user_ns, cred->egid)); NEW_AUX_ENT(AT_SECURE, bprm->secureexec); NEW_AUX_ENT(AT_RANDOM, (elf_addr_t)(unsigned long)u_rand_bytes); #ifdef ELF_HWCAP2 NEW_AUX_ENT(AT_HWCAP2, ELF_HWCAP2); #endif #ifdef ELF_HWCAP3 NEW_AUX_ENT(AT_HWCAP3, ELF_HWCAP3); #endif #ifdef ELF_HWCAP4 NEW_AUX_ENT(AT_HWCAP4, ELF_HWCAP4); #endif NEW_AUX_ENT(AT_EXECFN, bprm->exec); if (k_platform) { NEW_AUX_ENT(AT_PLATFORM, (elf_addr_t)(unsigned long)u_platform); } if (k_base_platform) { NEW_AUX_ENT(AT_BASE_PLATFORM, (elf_addr_t)(unsigned long)u_base_platform); } if (bprm->have_execfd) { NEW_AUX_ENT(AT_EXECFD, bprm->execfd); } #ifdef CONFIG_RSEQ NEW_AUX_ENT(AT_RSEQ_FEATURE_SIZE, offsetof(struct rseq, end)); NEW_AUX_ENT(AT_RSEQ_ALIGN, rseq_alloc_align()); #endif #undef NEW_AUX_ENT /* AT_NULL is zero; clear the rest too */ memset(elf_info, 0, (char *)mm->saved_auxv + sizeof(mm->saved_auxv) - (char *)elf_info); /* And advance past the AT_NULL entry. */ elf_info += 2; ei_index = elf_info - (elf_addr_t *)mm->saved_auxv; sp = STACK_ADD(p, ei_index); items = (argc + 1) + (envc + 1) + 1; bprm->p = STACK_ROUND(sp, items); /* Point sp at the lowest address on the stack */ #ifdef CONFIG_STACK_GROWSUP sp = (elf_addr_t __user *)bprm->p - items - ei_index; bprm->exec = (unsigned long)sp; /* XXX: PARISC HACK */ #else sp = (elf_addr_t __user *)bprm->p; #endif /* * Grow the stack manually; some architectures have a limit on how * far ahead a user-space access may be in order to grow the stack. */ if (mmap_write_lock_killable(mm)) return -EINTR; vma = find_extend_vma_locked(mm, bprm->p); mmap_write_unlock(mm); if (!vma) return -EFAULT; /* Now, let's put argc (and argv, envp if appropriate) on the stack */ if (put_user(argc, sp++)) return -EFAULT; /* Populate list of argv pointers back to argv strings. */ p = mm->arg_end = mm->arg_start; while (argc-- > 0) { size_t len; if (put_user((elf_addr_t)p, sp++)) return -EFAULT; len = strnlen_user((void __user *)p, MAX_ARG_STRLEN); if (!len || len > MAX_ARG_STRLEN) return -EINVAL; p += len; } if (put_user(0, sp++)) return -EFAULT; mm->arg_end = p; /* Populate list of envp pointers back to envp strings. */ mm->env_end = mm->env_start = p; while (envc-- > 0) { size_t len; if (put_user((elf_addr_t)p, sp++)) return -EFAULT; len = strnlen_user((void __user *)p, MAX_ARG_STRLEN); if (!len || len > MAX_ARG_STRLEN) return -EINVAL; p += len; } if (put_user(0, sp++)) return -EFAULT; mm->env_end = p; /* Put the elf_info on the stack in the right place. */ if (copy_to_user(sp, mm->saved_auxv, ei_index * sizeof(elf_addr_t))) return -EFAULT; return 0; } /* * Map "eppnt->p_filesz" bytes from "filep" offset "eppnt->p_offset" * into memory at "addr". (Note that p_filesz is rounded up to the * next page, so any extra bytes from the file must be wiped.) */ static unsigned long elf_map(struct file *filep, unsigned long addr, const struct elf_phdr *eppnt, int prot, int type, unsigned long total_size) { unsigned long map_addr; unsigned long size = eppnt->p_filesz + ELF_PAGEOFFSET(eppnt->p_vaddr); unsigned long off = eppnt->p_offset - ELF_PAGEOFFSET(eppnt->p_vaddr); addr = ELF_PAGESTART(addr); size = ELF_PAGEALIGN(size); /* mmap() will return -EINVAL if given a zero size, but a * segment with zero filesize is perfectly valid */ if (!size) return addr; /* * total_size is the size of the ELF (interpreter) image. * The _first_ mmap needs to know the full size, otherwise * randomization might put this image into an overlapping * position with the ELF binary image. (since size < total_size) * So we first map the 'big' image - and unmap the remainder at * the end. (which unmap is needed for ELF images with holes.) */ if (total_size) { total_size = ELF_PAGEALIGN(total_size); map_addr = vm_mmap(filep, addr, total_size, prot, type, off); if (!BAD_ADDR(map_addr)) vm_munmap(map_addr+size, total_size-size); } else map_addr = vm_mmap(filep, addr, size, prot, type, off); if ((type & MAP_FIXED_NOREPLACE) && PTR_ERR((void *)map_addr) == -EEXIST) pr_info("%d (%s): Uhuuh, elf segment at %px requested but the memory is mapped already\n", task_pid_nr(current), current->comm, (void *)addr); return(map_addr); } /* * Map "eppnt->p_filesz" bytes from "filep" offset "eppnt->p_offset" * into memory at "addr". Memory from "p_filesz" through "p_memsz" * rounded up to the next page is zeroed. */ static unsigned long elf_load(struct file *filep, unsigned long addr, const struct elf_phdr *eppnt, int prot, int type, unsigned long total_size) { unsigned long zero_start, zero_end; unsigned long map_addr; if (eppnt->p_filesz) { map_addr = elf_map(filep, addr, eppnt, prot, type, total_size); if (BAD_ADDR(map_addr)) return map_addr; if (eppnt->p_memsz > eppnt->p_filesz) { zero_start = map_addr + ELF_PAGEOFFSET(eppnt->p_vaddr) + eppnt->p_filesz; zero_end = map_addr + ELF_PAGEOFFSET(eppnt->p_vaddr) + eppnt->p_memsz; /* * Zero the end of the last mapped page but ignore * any errors if the segment isn't writable. */ if (padzero(zero_start) && (prot & PROT_WRITE)) return -EFAULT; } } else { map_addr = zero_start = ELF_PAGESTART(addr); zero_end = zero_start + ELF_PAGEOFFSET(eppnt->p_vaddr) + eppnt->p_memsz; } if (eppnt->p_memsz > eppnt->p_filesz) { /* * Map the last of the segment. * If the header is requesting these pages to be * executable, honour that (ppc32 needs this). */ int error; zero_start = ELF_PAGEALIGN(zero_start); zero_end = ELF_PAGEALIGN(zero_end); error = vm_brk_flags(zero_start, zero_end - zero_start, prot & PROT_EXEC); if (error) map_addr = error; } return map_addr; } static unsigned long total_mapping_size(const struct elf_phdr *phdr, int nr) { elf_addr_t min_addr = -1; elf_addr_t max_addr = 0; bool pt_load = false; int i; for (i = 0; i < nr; i++) { if (phdr[i].p_type == PT_LOAD) { min_addr = min(min_addr, ELF_PAGESTART(phdr[i].p_vaddr)); max_addr = max(max_addr, phdr[i].p_vaddr + phdr[i].p_memsz); pt_load = true; } } return pt_load ? (max_addr - min_addr) : 0; } static int elf_read(struct file *file, void *buf, size_t len, loff_t pos) { ssize_t rv; rv = kernel_read(file, buf, len, &pos); if (unlikely(rv != len)) { return (rv < 0) ? rv : -EIO; } return 0; } static unsigned long maximum_alignment(struct elf_phdr *cmds, int nr) { unsigned long alignment = 0; int i; for (i = 0; i < nr; i++) { if (cmds[i].p_type == PT_LOAD) { unsigned long p_align = cmds[i].p_align; /* skip non-power of two alignments as invalid */ if (!is_power_of_2(p_align)) continue; alignment = max(alignment, p_align);