| /* |
| * 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/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/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/dax.h> |
| #include <asm/uaccess.h> |
| #include <asm/param.h> |
| #include <asm/page.h> |
| |
| #ifndef user_long_t |
| #define user_long_t long |
| #endif |
| #ifndef user_siginfo_t |
| #define user_siginfo_t siginfo_t |
| #endif |
| |
| static int load_elf_binary(struct linux_binprm *bprm); |
| static unsigned long elf_map(struct file *, unsigned long, struct elf_phdr *, |
| int, int, unsigned long); |
| |
| #ifdef CONFIG_USELIB |
| static int load_elf_library(struct file *); |
| #else |
| #define load_elf_library NULL |
| #endif |
| |
| /* |
| * 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) & ~(unsigned long)(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, |
| .load_shlib = load_elf_library, |
| .core_dump = elf_core_dump, |
| .min_coredump = ELF_EXEC_PAGESIZE, |
| }; |
| |
| #define BAD_ADDR(x) ((unsigned long)(x) >= TASK_SIZE) |
| |
| static int set_brk(unsigned long start, unsigned long end) |
| { |
| start = ELF_PAGEALIGN(start); |
| end = ELF_PAGEALIGN(end); |
| if (end > start) { |
| unsigned long addr; |
| addr = vm_brk(start, end - start); |
| if (BAD_ADDR(addr)) |
| return addr; |
| } |
| current->mm->start_brk = current->mm->brk = end; |
| return 0; |
| } |
| |
| /* We need to explicitly zero any fractional pages |
| after the data section (i.e. bss). This would |
| contain the junk from the file that should not |
| be in memory |
| */ |
| static int padzero(unsigned long elf_bss) |
| { |
| unsigned long nbyte; |
| |
| nbyte = ELF_PAGEOFFSET(elf_bss); |
| if (nbyte) { |
| nbyte = ELF_MIN_ALIGN - nbyte; |
| if (clear_user((void __user *) elf_bss, 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 ; sp; }) |
| #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, struct elfhdr *exec, |
| unsigned long load_addr, unsigned long interp_load_addr) |
| { |
| unsigned long p = bprm->p; |
| int argc = bprm->argc; |
| int envc = bprm->envc; |
| elf_addr_t __user *argv; |
| elf_addr_t __user *envp; |
| 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 = 0; |
| 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 *)current->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[ei_index++] = id; \ |
| elf_info[ei_index++] = 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, load_addr + exec->e_phoff); |
| 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, 0); |
| NEW_AUX_ENT(AT_ENTRY, exec->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, security_bprm_secureexec(bprm)); |
| NEW_AUX_ENT(AT_RANDOM, (elf_addr_t)(unsigned long)u_rand_bytes); |
| #ifdef ELF_HWCAP2 |
| NEW_AUX_ENT(AT_HWCAP2, ELF_HWCAP2); |
| #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->interp_flags & BINPRM_FLAGS_EXECFD) { |
| NEW_AUX_ENT(AT_EXECFD, bprm->interp_data); |
| } |
| #undef NEW_AUX_ENT |
| /* AT_NULL is zero; clear the rest too */ |
| memset(&elf_info[ei_index], 0, |
| sizeof current->mm->saved_auxv - ei_index * sizeof elf_info[0]); |
| |
| /* And advance past the AT_NULL entry. */ |
| ei_index += 2; |
| |
| 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. |
| */ |
| vma = find_extend_vma(current->mm, bprm->p); |
| if (!vma) |
| return -EFAULT; |
| |
| /* Now, let's put argc (and argv, envp if appropriate) on the stack */ |
| if (__put_user(argc, sp++)) |
| return -EFAULT; |
| argv = sp; |
| envp = argv + argc + 1; |
| |
| /* Populate argv and envp */ |
| p = current->mm->arg_end = current->mm->arg_start; |
| while (argc-- > 0) { |
| size_t len; |
| if (__put_user((elf_addr_t)p, argv++)) |
| 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, argv)) |
| return -EFAULT; |
| current->mm->arg_end = current->mm->env_start = p; |
| while (envc-- > 0) { |
| size_t len; |
| if (__put_user((elf_addr_t)p, envp++)) |
| 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, envp)) |
| return -EFAULT; |
| current->mm->env_end = p; |
| |
| /* Put the elf_info on the stack in the right place. */ |
| sp = (elf_addr_t __user *)envp + 1; |
| if (copy_to_user(sp, elf_info, ei_index * sizeof(elf_addr_t))) |
| return -EFAULT; |
| return 0; |
| } |
| |
| #ifndef elf_map |
| |
| static unsigned long elf_map(struct file *filep, unsigned long addr, |
| 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); |
| |
| return(map_addr); |
| } |
| |
| #endif /* !elf_map */ |
| |
| static unsigned long total_mapping_size(struct elf_phdr *cmds, int nr) |
| { |
| int i, first_idx = -1, last_idx = -1; |
| |
| for (i = 0; i < nr; i++) { |
| if (cmds[i].p_type == PT_LOAD) { |
| last_idx = i; |
| if (first_idx == -1) |
| first_idx = i; |
| } |
| } |
| if (first_idx == -1) |
| return 0; |
| |
| return cmds[last_idx].p_vaddr + cmds[last_idx].p_memsz - |
| ELF_PAGESTART(cmds[first_idx].p_vaddr); |
| } |
| |
| /** |
| * load_elf_phdrs() - load ELF program headers |
| * @elf_ex: ELF header of the binary whose program headers should be loaded |
| * @elf_file: the opened ELF binary file |
| * |
| * Loads ELF program headers from the binary file elf_file, which has the ELF |
| * header pointed to by elf_ex, into a newly allocated array. The caller is |
| * responsible for freeing the allocated data. Returns an ERR_PTR upon failure. |
| */ |
| static struct elf_phdr *load_elf_phdrs(struct elfhdr *elf_ex, |
| struct file *elf_file) |
| { |
| struct elf_phdr *elf_phdata = NULL; |
| int retval, size, err = -1; |
| |
| /* |
| * If the size of this structure has changed, then punt, since |
| * we will be doing the wrong thing. |
| */ |
| if (elf_ex->e_phentsize != sizeof(struct elf_phdr)) |
| goto out; |
| |
| /* Sanity check the number of program headers... */ |
| if (elf_ex->e_phnum < 1 || |
| elf_ex->e_phnum > 65536U / sizeof(struct elf_phdr)) |
| goto out; |
| |
| /* ...and their total size. */ |
| size = sizeof(struct elf_phdr) * elf_ex->e_phnum; |
| if (size > ELF_MIN_ALIGN) |
| goto out; |
| |
| elf_phdata = kmalloc(size, GFP_KERNEL); |
| if (!elf_phdata) |
| goto out; |
| |
| /* Read in the program headers */ |
| retval = kernel_read(elf_file, elf_ex->e_phoff, |
| (char *)elf_phdata, size); |
| if (retval != size) { |
| err = (retval < 0) ? retval : -EIO; |
| goto out; |
| } |
| |
| /* Success! */ |
| err = 0; |
| out: |
| if (err) { |
| kfree(elf_phdata); |
| elf_phdata = NULL; |
| } |
| return elf_phdata; |
| } |
| |
| #ifndef CONFIG_ARCH_BINFMT_ELF_STATE |
| |
| /** |
| * struct arch_elf_state - arch-specific ELF loading state |
| * |
| * This structure is used to preserve architecture specific data during |
| * the loading of an ELF file, throughout the checking of architecture |
| * specific ELF headers & through to the point where the ELF load is |
| * known to be proceeding (ie. SET_PERSONALITY). |
| * |
| * This implementation is a dummy for architectures which require no |
| * specific state. |
| */ |
| struct arch_elf_state { |
| }; |
| |
| #define INIT_ARCH_ELF_STATE {} |
| |
| /** |
| * arch_elf_pt_proc() - check a PT_LOPROC..PT_HIPROC ELF program header |
| * @ehdr: The main ELF header |
| * @phdr: The program header to check |
| * @elf: The open ELF file |
| * @is_interp: True if the phdr is from the interpreter of the ELF being |
| * loaded, else false. |
| * @state: Architecture-specific state preserved throughout the process |
| * of loading the ELF. |
| * |
| * Inspects the program header phdr to validate its correctness and/or |
| * suitability for the system. Called once per ELF program header in the |
| * range PT_LOPROC to PT_HIPROC, for both the ELF being loaded and its |
| * interpreter. |
| * |
| * Return: Zero to proceed with the ELF load, non-zero to fail the ELF load |
| * with that return code. |
| */ |
| static inline int arch_elf_pt_proc(struct elfhdr *ehdr, |
| struct elf_phdr *phdr, |
| struct file *elf, bool is_interp, |
| struct arch_elf_state *state) |
| { |
| /* Dummy implementation, always proceed */ |
| return 0; |
| } |
| |
| /** |
| * arch_check_elf() - check an ELF executable |
| * @ehdr: The main ELF header |
| * @has_interp: True if the ELF has an interpreter, else false. |
| * @interp_ehdr: The interpreter's ELF header |
| * @state: Architecture-specific state preserved throughout the process |
| * of loading the ELF. |
| * |
| * Provides a final opportunity for architecture code to reject the loading |
| * of the ELF & cause an exec syscall to return an error. This is called after |
| * all program headers to be checked by arch_elf_pt_proc have been. |
| * |
| * Return: Zero to proceed with the ELF load, non-zero to fail the ELF load |
| * with that return code. |
| */ |
| static inline int arch_check_elf(struct elfhdr *ehdr, bool has_interp, |
| struct elfhdr *interp_ehdr, |
| struct arch_elf_state *state) |
| { |
| /* Dummy implementation, always proceed */ |
| return 0; |
| } |
| |
| #endif /* !CONFIG_ARCH_BINFMT_ELF_STATE */ |
| |
| /* This is much more generalized than the library routine read function, |
| so we keep this separate. Technically the library read function |
| is only provided so that we can read a.out libraries that have |
| an ELF header */ |
| |
| static unsigned long load_elf_interp(struct elfhdr *interp_elf_ex, |
| struct file *interpreter, unsigned long *interp_map_addr, |
| unsigned long no_base, struct elf_phdr *interp_elf_phdata) |
| { |
| struct elf_phdr *eppnt; |
| unsigned long load_addr = 0; |
| int load_addr_set = 0; |
| unsigned long last_bss = 0, elf_bss = 0; |
| unsigned long error = ~0UL; |
| unsigned long total_size; |
| int i; |
| |
| /* First of all, some simple consistency checks */ |
| if (interp_elf_ex->e_type != ET_EXEC && |
| interp_elf_ex->e_type != ET_DYN) |
| goto out; |
| if (!elf_check_arch(interp_elf_ex)) |
| goto out; |
| if (!interpreter->f_op->mmap) |
| goto out; |
| |
| total_size = total_mapping_size(interp_elf_phdata, |
| interp_elf_ex->e_phnum); |
| if (!total_size) { |
| error = -EINVAL; |
| goto out; |
| } |
| |
| eppnt = interp_elf_phdata; |
| for (i = 0; i < interp_elf_ex->e_phnum; i++, eppnt++) { |
| if (eppnt->p_type == PT_LOAD) { |
| int elf_type = MAP_PRIVATE | MAP_DENYWRITE; |
| int elf_prot = 0; |
| unsigned long vaddr = 0; |
| unsigned long k, map_addr; |
| |
| if (eppnt->p_flags & PF_R) |
| elf_prot = PROT_READ; |
| if (eppnt->p_flags & PF_W) |
| elf_prot |= PROT_WRITE; |
| if (eppnt->p_flags & PF_X) |
| elf_prot |= PROT_EXEC; |
| vaddr = eppnt->p_vaddr; |
| if (interp_elf_ex->e_type == ET_EXEC || load_addr_set) |
| elf_type |= MAP_FIXED; |
| else if (no_base && interp_elf_ex->e_type == ET_DYN) |
| load_addr = -vaddr; |
| |
| map_addr = elf_map(interpreter, load_addr + vaddr, |
| eppnt, elf_prot, elf_type, total_size); |
| total_size = 0; |
| if (!*interp_map_addr) |
| *interp_map_addr = map_addr; |
| error = map_addr; |
| if (BAD_ADDR(map_addr)) |
| goto out; |
| |
| if (!load_addr_set && |
| interp_elf_ex->e_type == ET_DYN) { |
| load_addr = map_addr - ELF_PAGESTART(vaddr); |
| load_addr_set = 1; |
| } |
| |
| /* |
| * Check to see if the section's size will overflow the |
| * allowed task size. Note that p_filesz must always be |
| * <= p_memsize so it's only necessary to check p_memsz. |
| */ |
| k = load_addr + eppnt->p_vaddr; |
| if (BAD_ADDR(k) || |
| eppnt->p_filesz > eppnt->p_memsz || |
| eppnt->p_memsz > TASK_SIZE || |
| TASK_SIZE - eppnt->p_memsz < k) { |
| error = -ENOMEM; |
| goto out; |
| } |
| |
| /* |
| * Find the end of the file mapping for this phdr, and |
| * keep track of the largest address we see for this. |
| */ |
| k = load_addr + eppnt->p_vaddr + eppnt->p_filesz; |
| if (k > elf_bss) |
| elf_bss = k; |
| |
| /* |
| * Do the same thing for the memory mapping - between |
| * elf_bss and last_bss is the bss section. |
| */ |
| k = load_addr + eppnt->p_memsz + eppnt->p_vaddr; |
| if (k > last_bss) |
| last_bss = k; |
| } |
| } |
| |
| if (last_bss > elf_bss) { |
| /* |
| * Now fill out the bss section. First pad the last page up |
| * to the page boundary, and then perform a mmap to make sure |
| * that there are zero-mapped pages up to and including the |
| * last bss page. |
| */ |
| if (padzero(elf_bss)) { |
| error = -EFAULT; |
| goto out; |
| } |
| |
| /* What we have mapped so far */ |
| elf_bss = ELF_PAGESTART(elf_bss + ELF_MIN_ALIGN - 1); |
| |
| /* Map the last of the bss segment */ |
| error = vm_brk(elf_bss, last_bss - elf_bss); |
| if (BAD_ADDR(error)) |
| goto out; |
| } |
| |
| error = load_addr; |
| out: |
| return error; |
| } |
| |
| /* |
| * These are the functions used to load ELF style executables and shared |
| * libraries. There is no binary dependent code anywhere else. |
| */ |
| |
| #ifndef STACK_RND_MASK |
| #define STACK_RND_MASK (0x7ff >> (PAGE_SHIFT - 12)) /* 8MB of VA */ |
| #endif |
| |
| static unsigned long randomize_stack_top(unsigned long stack_top) |
| { |
| unsigned long random_variable = 0; |
| |
| if ((current->flags & PF_RANDOMIZE) && |
| !(current->personality & ADDR_NO_RANDOMIZE)) { |
| random_variable = get_random_long(); |
| random_variable &= STACK_RND_MASK; |
| random_variable <<= PAGE_SHIFT; |
| } |
| #ifdef CONFIG_STACK_GROWSUP |
| return PAGE_ALIGN(stack_top) + random_variable; |
| #else |
| return PAGE_ALIGN(stack_top) - random_variable; |
| #endif |
| } |
| |
| static int load_elf_binary(struct linux_binprm *bprm) |
| { |
| struct file *interpreter = NULL; /* to shut gcc up */ |
| unsigned long load_addr = 0, load_bias = 0; |
| int load_addr_set = 0; |
| char * elf_interpreter = NULL; |
| unsigned long error; |
| struct elf_phdr *elf_ppnt, *elf_phdata, *interp_elf_phdata = NULL; |
| unsigned long elf_bss, elf_brk; |
| int retval, i; |
| unsigned long elf_entry; |
| unsigned long interp_load_addr = 0; |
| unsigned long start_code, end_code, start_data, end_data; |
| unsigned long reloc_func_desc __maybe_unused = 0; |
| int executable_stack = EXSTACK_DEFAULT; |
| struct pt_regs *regs = current_pt_regs(); |
| struct { |
| struct elfhdr elf_ex; |
| struct elfhdr interp_elf_ex; |
| } *loc; |
| struct arch_elf_state arch_state = INIT_ARCH_ELF_STATE; |
| |
| loc = kmalloc(sizeof(*loc), GFP_KERNEL); |
| if (!loc) { |
| retval = -ENOMEM; |
| goto out_ret; |
| } |
| |
| /* Get the exec-header */ |
| loc->elf_ex = *((struct elfhdr *)bprm->buf); |
| |
| retval = -ENOEXEC; |
| /* First of all, some simple consistency checks */ |
| if (memcmp(loc->elf_ex.e_ident, ELFMAG, SELFMAG) != 0) |
| goto out; |
| |
| if (loc->elf_ex.e_type != ET_EXEC && loc->elf_ex.e_type != ET_DYN) |
| goto out; |
| if (!elf_check_arch(&loc->elf_ex)) |
| goto out; |
| if (!bprm->file->f_op->mmap) |
| goto out; |
| |
| elf_phdata = load_elf_phdrs(&loc->elf_ex, bprm->file); |
| if (!elf_phdata) |
| goto out; |
| |
| elf_ppnt = elf_phdata; |
| elf_bss = 0; |
| elf_brk = 0; |
| |
| start_code = ~0UL; |
| end_code = 0; |
| start_data = 0; |
| end_data = 0; |
| |
| for (i = 0; i < loc->elf_ex.e_phnum; i++) { |
| if (elf_ppnt->p_type == PT_INTERP) { |
| /* This is the program interpreter used for |
| * shared libraries - for now assume that this |
| * is an a.out format binary |
| */ |
| retval = -ENOEXEC; |
| if (elf_ppnt->p_filesz > PATH_MAX || |
| elf_ppnt->p_filesz < 2) |
| goto out_free_ph; |
| |
| retval = -ENOMEM; |
| elf_interpreter = kmalloc(elf_ppnt->p_filesz, |
| GFP_KERNEL); |
| if (!elf_interpreter) |
| goto out_free_ph; |
| |
| retval = kernel_read(bprm->file, elf_ppnt->p_offset, |
| elf_interpreter, |
| elf_ppnt->p_filesz); |
| if (retval != elf_ppnt->p_filesz) { |
| if (retval >= 0) |
| retval = -EIO; |
| goto out_free_interp; |
| } |
| /* make sure path is NULL terminated */ |
| retval = -ENOEXEC; |
| if (elf_interpreter[elf_ppnt->p_filesz - 1] != '\0') |
| goto out_free_interp; |
| |
| interpreter = open_exec(elf_interpreter); |
| retval = PTR_ERR(interpreter); |
| if (IS_ERR(interpreter)) |
| goto out_free_interp; |
| |
| /* |
| * If the binary is not readable then enforce |
| * mm->dumpable = 0 regardless of the interpreter's |
| * permissions. |
| */ |
| would_dump(bprm, interpreter); |
| |
| /* Get the exec headers */ |
| retval = kernel_read(interpreter, 0, |
| (void *)&loc->interp_elf_ex, |
| sizeof(loc->interp_elf_ex)); |
| if (retval != sizeof(loc->interp_elf_ex)) { |
| if (retval >= 0) |
| retval = -EIO; |
| goto out_free_dentry; |
| } |
| |
| break; |
| } |
| elf_ppnt++; |
| } |
| |
| elf_ppnt = elf_phdata; |
| for (i = 0; i < loc->elf_ex.e_phnum; i++, elf_ppnt++) |
| switch (elf_ppnt->p_type) { |
| case PT_GNU_STACK: |
| if (elf_ppnt->p_flags & PF_X) |
| executable_stack = EXSTACK_ENABLE_X; |
| else |
| executable_stack = EXSTACK_DISABLE_X; |
| break; |
| |
| case PT_LOPROC ... PT_HIPROC: |
| retval = arch_elf_pt_proc(&loc->elf_ex, elf_ppnt, |
| bprm->file, false, |
| &arch_state); |
| if (retval) |
| goto out_free_dentry; |
| break; |
| } |
| |
| /* Some simple consistency checks for the interpreter */ |
| if (elf_interpreter) { |
| retval = -ELIBBAD; |
| /* Not an ELF interpreter */ |
| if (memcmp(loc->interp_elf_ex.e_ident, ELFMAG, SELFMAG) != 0) |
| goto out_free_dentry; |
| /* Verify the interpreter has a valid arch */ |
| if (!elf_check_arch(&loc->interp_elf_ex)) |
| goto out_free_dentry; |
| |
| /* Load the interpreter program headers */ |
| interp_elf_phdata = load_elf_phdrs(&loc->interp_elf_ex, |
| interpreter); |
| if (!interp_elf_phdata) |
| goto out_free_dentry; |
| |
| /* Pass PT_LOPROC..PT_HIPROC headers to arch code */ |
| elf_ppnt = interp_elf_phdata; |
| for (i = 0; i < loc->interp_elf_ex.e_phnum; i++, elf_ppnt++) |
| switch (elf_ppnt->p_type) { |
| case PT_LOPROC ... PT_HIPROC: |
| retval = arch_elf_pt_proc(&loc->interp_elf_ex, |
| elf_ppnt, interpreter, |
| true, &arch_state); |
| if (retval) |
| goto out_free_dentry; |
| break; |
| } |
| } |
| |
| /* |
| * Allow arch code to reject the ELF at this point, whilst it's |
| * still possible to return an error to the code that invoked |
| * the exec syscall. |
| */ |
| retval = arch_check_elf(&loc->elf_ex, |
| !!interpreter, &loc->interp_elf_ex, |
| &arch_state); |
| if (retval) |
| goto out_free_dentry; |
| |
| /* Flush all traces of the currently running executable */ |
| retval = flush_old_exec(bprm); |
| if (retval) |
| goto out_free_dentry; |
| |
| /* Do this immediately, since STACK_TOP as used in setup_arg_pages |
| may depend on the personality. */ |
| SET_PERSONALITY2(loc->elf_ex, &arch_state); |
| if (elf_read_implies_exec(loc->elf_ex, executable_stack)) |
| current->personality |= READ_IMPLIES_EXEC; |
| |
| if (!(current->personality & ADDR_NO_RANDOMIZE) && randomize_va_space) |
| current->flags |= PF_RANDOMIZE; |
| |
| setup_new_exec(bprm); |
| |
| /* Do this so that we can load the interpreter, if need be. We will |
| change some of these later */ |
| retval = setup_arg_pages(bprm, randomize_stack_top(STACK_TOP), |
| executable_stack); |
| if (retval < 0) |
| goto out_free_dentry; |
| |
| current->mm->start_stack = bprm->p; |
| |
| /* Now we do a little grungy work by mmapping the ELF image into |
| the correct location in memory. */ |
| for(i = 0, elf_ppnt = elf_phdata; |
| i < loc->elf_ex.e_phnum; i++, elf_ppnt++) { |
| int elf_prot = 0, elf_flags; |
| unsigned long k, vaddr; |
| unsigned long total_size = 0; |
| |
| if (elf_ppnt->p_type != PT_LOAD) |
| continue; |
| |
| if (unlikely (elf_brk > elf_bss)) { |
| unsigned long nbyte; |
| |
| /* There was a PT_LOAD segment with p_memsz > p_filesz |
| before this one. Map anonymous pages, if needed, |
| and clear the area. */ |
| retval = set_brk(elf_bss + load_bias, |
| elf_brk + load_bias); |
| if (retval) |
| goto out_free_dentry; |
| nbyte = ELF_PAGEOFFSET(elf_bss); |
| if (nbyte) { |
| nbyte = ELF_MIN_ALIGN - nbyte; |
| if (nbyte > elf_brk - elf_bss) |
| nbyte = elf_brk - elf_bss; |
| if (clear_user((void __user *)elf_bss + |
| load_bias, nbyte)) { |
| /* |
| * This bss-zeroing can fail if the ELF |
| * file specifies odd protections. So |
| * we don't check the return value |
| */ |
| } |
| } |
| } |
| |
| if (elf_ppnt->p_flags & PF_R) |
| elf_prot |= PROT_READ; |
| if (elf_ppnt->p_flags & PF_W) |
| elf_prot |= PROT_WRITE; |
| if (elf_ppnt->p_flags & PF_X) |
| elf_prot |= PROT_EXEC; |
| |
| elf_flags = MAP_PRIVATE | MAP_DENYWRITE | MAP_EXECUTABLE; |
| |
| vaddr = elf_ppnt->p_vaddr; |
| if (loc->elf_ex.e_type == ET_EXEC || load_addr_set) { |
| elf_flags |= MAP_FIXED; |
| } else if (loc->elf_ex.e_type == ET_DYN) { |
| /* Try and get dynamic programs out of the way of the |
| * default mmap base, as well as whatever program they |
| * might try to exec. This is because the brk will |
| * follow the loader, and is not movable. */ |
| load_bias = ELF_ET_DYN_BASE - vaddr; |
| if (current->flags & PF_RANDOMIZE) |
| load_bias += arch_mmap_rnd(); |
| load_bias = ELF_PAGESTART(load_bias); |
| total_size = total_mapping_size(elf_phdata, |
| loc->elf_ex.e_phnum); |
| if (!total_size) { |
| retval = -EINVAL; |
| goto out_free_dentry; |
| } |
| } |
| |
| error = elf_map(bprm->file, load_bias + vaddr, elf_ppnt, |
| elf_prot, elf_flags, total_size); |
| if (BAD_ADDR(error)) { |
| retval = IS_ERR((void *)error) ? |
| PTR_ERR((void*)error) : -EINVAL; |
| goto out_free_dentry; |
| } |
| |
| if (!load_addr_set) { |
| load_addr_set = 1; |
| load_addr = (elf_ppnt->p_vaddr - elf_ppnt->p_offset); |
| if (loc->elf_ex.e_type == ET_DYN) { |
| load_bias += error - |
| ELF_PAGESTART(load_bias + vaddr); |
| load_addr += load_bias; |
| reloc_func_desc = load_bias; |
| } |
| } |
| k = elf_ppnt->p_vaddr; |
| if (k < start_code) |
| start_code = k; |
| if (start_data < k) |
| start_data = k; |
| |
| /* |
| * Check to see if the section's size will overflow the |
| * allowed task size. Note that p_filesz must always be |
| * <= p_memsz so it is only necessary to check p_memsz. |
| */ |
| if (BAD_ADDR(k) || elf_ppnt->p_filesz > elf_ppnt->p_memsz || |
| elf_ppnt->p_memsz > TASK_SIZE || |
| TASK_SIZE - elf_ppnt->p_memsz < k) { |
| /* set_brk can never work. Avoid overflows. */ |
| retval = -EINVAL; |
| goto out_free_dentry; |
| } |
| |
| k = elf_ppnt->p_vaddr + elf_ppnt->p_filesz; |
| |
| if (k > elf_bss) |
| elf_bss = k; |
| if ((elf_ppnt->p_flags & PF_X) && end_code < k) |
| end_code = k; |
| if (end_data < k) |
| end_data = k; |
| k = elf_ppnt->p_vaddr + elf_ppnt->p_memsz; |
| if (k > elf_brk) |
| elf_brk = k; |
| } |
| |
| loc->elf_ex.e_entry += load_bias; |
| elf_bss += load_bias; |
| elf_brk += load_bias; |
| start_code += load_bias; |
| end_code += load_bias; |
| start_data += load_bias; |
| end_data += load_bias; |
| |
| /* Calling set_brk effectively mmaps the pages that we need |
| * for the bss and break sections. We must do this before |
| * mapping in the interpreter, to make sure it doesn't wind |
| * up getting placed where the bss needs to go. |
| */ |
| retval = set_brk(elf_bss, elf_brk); |
| if (retval) |
| goto out_free_dentry; |
| if (likely(elf_bss != elf_brk) && unlikely(padzero(elf_bss))) { |
| retval = -EFAULT; /* Nobody gets to see this, but.. */ |
| goto out_free_dentry; |
| } |
| |
| if (elf_interpreter) { |
| unsigned long interp_map_addr = 0; |
| |
| elf_entry = load_elf_interp(&loc->interp_elf_ex, |
| interpreter, |
| &interp_map_addr, |
| load_bias, interp_elf_phdata); |
| if (!IS_ERR((void *)elf_entry)) { |
| /* |
| * load_elf_interp() returns relocation |
| * adjustment |
| */ |
| interp_load_addr = elf_entry; |
| elf_entry += loc->interp_elf_ex.e_entry; |
| } |
| if (BAD_ADDR(elf_entry)) { |
| retval = IS_ERR((void *)elf_entry) ? |
| (int)elf_entry : -EINVAL; |
| goto out_free_dentry; |
| } |
| reloc_func_desc = interp_load_addr; |
| |
| allow_write_access(interpreter); |
| fput(interpreter); |
| kfree(elf_interpreter); |
| } else { |
| elf_entry = loc->elf_ex.e_entry; |
| if (BAD_ADDR(elf_entry)) { |
| retval = -EINVAL; |
| goto out_free_dentry; |
| } |
| } |
| |
| kfree(interp_elf_phdata); |
| kfree(elf_phdata); |
| |
| set_binfmt(&elf_format); |
| |
| #ifdef ARCH_HAS_SETUP_ADDITIONAL_PAGES |
| retval = arch_setup_additional_pages(bprm, !!elf_interpreter); |
| if (retval < 0) |
| goto out; |
| #endif /* ARCH_HAS_SETUP_ADDITIONAL_PAGES */ |
| |
| install_exec_creds(bprm); |
| retval = create_elf_tables(bprm, &loc->elf_ex, |
| load_addr, interp_load_addr); |
| if (retval < 0) |
| goto out; |
| /* N.B. passed_fileno might not be initialized? */ |
| current->mm->end_code = end_code; |
| current->mm->start_code = start_code; |
| current->mm->start_data = start_data; |
| current->mm->end_data = end_data; |
| current->mm->start_stack = bprm->p; |
| |
| if ((current->flags & PF_RANDOMIZE) && (randomize_va_space > 1)) { |
| current->mm->brk = current->mm->start_brk = |
| arch_randomize_brk(current->mm); |
| #ifdef compat_brk_randomized |
| current->brk_randomized = 1; |
| #endif |
| } |
| |
| if (current->personality & MMAP_PAGE_ZERO) { |
| /* Why this, you ask??? Well SVr4 maps page 0 as read-only, |
| and some applications "depend" upon this behavior. |
| Since we do not have the power to recompile these, we |
| emulate the SVr4 behavior. Sigh. */ |
| error = vm_mmap(NULL, 0, PAGE_SIZE, PROT_READ | PROT_EXEC, |
| MAP_FIXED | MAP_PRIVATE, 0); |
| } |
| |
| #ifdef ELF_PLAT_INIT |
| /* |
| * The ABI may specify that certain registers be set up in special |
| * ways (on i386 %edx is the address of a DT_FINI function, for |
| * example. In addition, it may also specify (eg, PowerPC64 ELF) |
| * that the e_entry field is the address of the function descriptor |
| * for the startup routine, rather than the address of the startup |
| * routine itself. This macro performs whatever initialization to |
| * the regs structure is required as well as any relocations to the |
| * function descriptor entries when executing dynamically links apps. |
| */ |
| ELF_PLAT_INIT(regs, reloc_func_desc); |
| #endif |
| |
| start_thread(regs, elf_entry, bprm->p); |
| retval = 0; |
| out: |
| kfree(loc); |
| out_ret: |
| return retval; |
| |
| /* error cleanup */ |
| out_free_dentry: |
| kfree(interp_elf_phdata); |
| allow_write_access(interpreter); |
| if (interpreter) |
| fput(interpreter); |
| out_free_interp: |
| kfree(elf_interpreter); |
| out_free_ph: |
| kfree(elf_phdata); |
| goto out; |
| } |
| |
| #ifdef CONFIG_USELIB |
| /* This is really simpleminded and specialized - we are loading an |
| a.out library that is given an ELF header. */ |
| static int load_elf_library(struct file *file) |
| { |
| struct elf_phdr *elf_phdata; |
| struct elf_phdr *eppnt; |
| unsigned long elf_bss, bss, len; |
| int retval, error, i, j; |
| struct elfhdr elf_ex; |
| |
| error = -ENOEXEC; |
| retval = kernel_read(file, 0, (char *)&elf_ex, sizeof(elf_ex)); |
| if (retval != sizeof(elf_ex)) |
| goto out; |
| |
| if (memcmp(elf_ex.e_ident, ELFMAG, SELFMAG) != 0) |
| goto out; |
| |
| /* First of all, some simple consistency checks */ |
| if (elf_ex.e_type != ET_EXEC || elf_ex.e_phnum > 2 || |
| !elf_check_arch(&elf_ex) || !file->f_op->mmap) |
| goto out; |
| |
| /* Now read in all of the header information */ |
| |
| j = sizeof(struct elf_phdr) * elf_ex.e_phnum; |
| /* j < ELF_MIN_ALIGN because elf_ex.e_phnum <= 2 */ |
| |
| error = -ENOMEM; |
| elf_phdata = kmalloc(j, GFP_KERNEL); |
| if (!elf_phdata) |
| goto out; |
| |
| eppnt = elf_phdata; |
| error = -ENOEXEC; |
| retval = kernel_read(file, elf_ex.e_phoff, (char *)eppnt, j); |
| if (retval != j) |
| goto out_free_ph; |
| |
| for (j = 0, i = 0; i<elf_ex.e_phnum; i++) |
| if ((eppnt + i)->p_type == PT_LOAD) |
| j++; |
| if (j != 1) |
| goto out_free_ph; |
| |
| while (eppnt->p_type != PT_LOAD) |
| eppnt++; |
| |
| /* Now use mmap to map the library into memory. */ |
| error = vm_mmap(file, |
| ELF_PAGESTART(eppnt->p_vaddr), |
| (eppnt->p_filesz + |
| ELF_PAGEOFFSET(eppnt->p_vaddr)), |
| PROT_READ | PROT_WRITE | PROT_EXEC, |
| MAP_FIXED | MAP_PRIVATE | MAP_DENYWRITE, |
| (eppnt->p_offset - |
| ELF_PAGEOFFSET(eppnt->p_vaddr))); |
| if (error != ELF_PAGESTART(eppnt->p_vaddr)) |
| goto out_free_ph; |
| |
| elf_bss = eppnt->p_vaddr + eppnt->p_filesz; |
| if (padzero(elf_bss)) { |
| error = -EFAULT; |
| goto out_free_ph; |
| } |
| |
| len = ELF_PAGESTART(eppnt->p_filesz + eppnt->p_vaddr + |
| ELF_MIN_ALIGN - 1); |
| bss = eppnt->p_memsz + eppnt->p_vaddr; |
| if (bss > len) |
| vm_brk(len, bss - len); |
| error = 0; |
| |
| out_free_ph: |
| kfree(elf_phdata); |
| out: |
| return error; |
| } |
| #endif /* #ifdef CONFIG_USELIB */ |
| |
| #ifdef CONFIG_ELF_CORE |
| /* |
| * ELF core dumper |
| * |
| * Modelled on fs/exec.c:aout_core_dump() |
| * Jeremy Fitzhardinge <jeremy@sw.oz.au> |
| */ |
| |
| /* |
| * The purpose of always_dump_vma() is to make sure that special kernel mappings |
| * that are useful for post-mortem analysis are included in every core dump. |
| * In that way we ensure that the core dump is fully interpretable later |
| * without matching up the same kernel and hardware config to see what PC values |
| * meant. These special mappings include - vDSO, vsyscall, and other |
| * architecture specific mappings |
| */ |
| static bool always_dump_vma(struct vm_area_struct *vma) |
| { |
| /* Any vsyscall mappings? */ |
| if (vma == get_gate_vma(vma->vm_mm)) |
| return true; |
| |
| /* |
| * Assume that all vmas with a .name op should always be dumped. |
| * If this changes, a new vm_ops field can easily be added. |
| */ |
| if (vma->vm_ops && vma->vm_ops->name && vma->vm_ops->name(vma)) |
| return true; |
| |
| /* |
| * arch_vma_name() returns non-NULL for special architecture mappings, |
| * such as vDSO sections. |
| */ |
| if (arch_vma_name(vma)) |
| return true; |
| |
| return false; |
| } |
| |
| /* |
| * Decide what to dump of a segment, part, all or none. |
| */ |
| static unsigned long vma_dump_size(struct vm_area_struct *vma, |
| unsigned long mm_flags) |
| { |
| #define FILTER(type) (mm_flags & (1UL << MMF_DUMP_##type)) |
| |
| /* always dump the vdso and vsyscall sections */ |
| if (always_dump_vma(vma)) |
| goto whole; |
| |
| if (vma->vm_flags & VM_DONTDUMP) |
| return 0; |
| |
| /* support for DAX */ |
| if (vma_is_dax(vma)) { |
| if ((vma->vm_flags & VM_SHARED) && FILTER(DAX_SHARED)) |
| goto whole; |
| if (!(vma->vm_flags & VM_SHARED) && FILTER(DAX_PRIVATE)) |
| goto whole; |
| return 0; |
| } |
| |
| /* Hugetlb memory check */ |
| if (vma->vm_flags & VM_HUGETLB) { |
| if ((vma->vm_flags & VM_SHARED) && FILTER(HUGETLB_SHARED)) |
| goto whole; |
| if (!(vma->vm_flags & VM_SHARED) && FILTER(HUGETLB_PRIVATE)) |
| goto whole; |
| return 0; |
| } |
| |
| /* Do not dump I/O mapped devices or special mappings */ |
| if (vma->vm_flags & VM_IO) |
| return 0; |
| |
| /* By default, dump shared memory if mapped from an anonymous file. */ |
| if (vma->vm_flags & VM_SHARED) { |
| if (file_inode(vma->vm_file)->i_nlink == 0 ? |
| FILTER(ANON_SHARED) : FILTER(MAPPED_SHARED)) |
| goto whole; |
| return 0; |
| } |
| |
| /* Dump segments that have been written to. */ |
| if (vma->anon_vma && FILTER(ANON_PRIVATE)) |
| goto whole; |
| if (vma->vm_file == NULL) |
| return 0; |
| |
| if (FILTER(MAPPED_PRIVATE)) |
| goto whole; |
| |
| /* |
| * If this looks like the beginning of a DSO or executable mapping, |
| * check for an ELF header. If we find one, dump the first page to |
| * aid in determining what was mapped here. |
| */ |
| if (FILTER(ELF_HEADERS) && |
| vma->vm_pgoff == 0 && (vma->vm_flags & VM_READ)) { |
| u32 __user *header = (u32 __user *) vma->vm_start; |
| u32 word; |
| mm_segment_t fs = get_fs(); |
| /* |
| * Doing it this way gets the constant folded by GCC. |
| */ |
| union { |
| u32 cmp; |
| char elfmag[SELFMAG]; |
| } magic; |
| BUILD_BUG_ON(SELFMAG != sizeof word); |
| magic.elfmag[EI_MAG0] = ELFMAG0; |
| magic.elfmag[EI_MAG1] = ELFMAG1; |
| magic.elfmag[EI_MAG2] = ELFMAG2; |
| magic.elfmag[EI_MAG3] = ELFMAG3; |
| /* |
| * Switch to the user "segment" for get_user(), |
| * then put back what elf_core_dump() had in place. |
| */ |
| set_fs(USER_DS); |
| if (unlikely(get_user(word, header))) |
| word = 0; |
| set_fs(fs); |
| if (word == magic.cmp) |
| return PAGE_SIZE; |
| } |
| |
| #undef FILTER |
| |
| return 0; |
| |
| whole: |
| return vma->vm_end - vma->vm_start; |
| } |
| |
| /* An ELF note in memory */ |
| struct memelfnote |
| { |
| const char *name; |
| int type; |
| unsigned int datasz; |
| void *data; |
| }; |
| |
| static int notesize(struct memelfnote *en) |
| { |
| int sz; |
| |
| sz = sizeof(struct elf_note); |
| sz += roundup(strlen(en->name) + 1, 4); |
| sz += roundup(en->datasz, 4); |
| |
| return sz; |
| } |
| |
| static int writenote(struct memelfnote *men, struct coredump_params *cprm) |
| { |
| struct elf_note en; |
| en.n_namesz = strlen(men->name) + 1; |
| en.n_descsz = men->datasz; |
| en.n_type = men->type; |
| |
| return dump_emit(cprm, &en, sizeof(en)) && |
| dump_emit(cprm, men->name, en.n_namesz) && dump_align(cprm, 4) && |
| dump_emit(cprm, men->data, men->datasz) && dump_align(cprm, 4); |
| } |
| |
| static void fill_elf_header(struct elfhdr *elf, int segs, |
| u16 machine, u32 flags) |
| { |
| memset(elf, 0, sizeof(*elf)); |
| |
| memcpy(elf->e_ident, ELFMAG, SELFMAG); |
| elf->e_ident[EI_CLASS] = ELF_CLASS; |
| elf->e_ident[EI_DATA] = ELF_DATA; |
| elf->e_ident[EI_VERSION] = EV_CURRENT; |
| elf->e_ident[EI_OSABI] = ELF_OSABI; |
| |
| elf->e_type = ET_CORE; |
| elf->e_machine = machine; |
| elf->e_version = EV_CURRENT; |
| elf->e_phoff = sizeof(struct elfhdr); |
| elf->e_flags = flags; |
| elf->e_ehsize = sizeof(struct elfhdr); |
| elf->e_phentsize = sizeof(struct elf_phdr); |
| elf->e_phnum = segs; |
| |
| return; |
| } |
| |
| static void fill_elf_note_phdr(struct elf_phdr *phdr, int sz, loff_t offset) |
| { |
| phdr->p_type = PT_NOTE; |
| phdr->p_offset = offset; |
| phdr->p_vaddr = 0; |
| phdr->p_paddr = 0; |
| phdr->p_filesz = sz; |
| phdr->p_memsz = 0; |
| phdr->p_flags = 0; |
| phdr->p_align = 0; |
| return; |
| } |
| |
| static void fill_note(struct memelfnote *note, const char *name, int type, |
| unsigned int sz, void *data) |
| { |
| note->name = name; |
| note->type = type; |
| note->datasz = sz; |
| note->data = data; |
| return; |
| } |
| |
| /* |
| * fill up all the fields in prstatus from the given task struct, except |
| * registers which need to be filled up separately. |
| */ |
| static void fill_prstatus(struct elf_prstatus *prstatus, |
| struct task_struct *p, long signr) |
| { |
| prstatus->pr_info.si_signo = prstatus->pr_cursig = signr; |
| prstatus->pr_sigpend = p->pending.signal.sig[0]; |
| prstatus->pr_sighold = p->blocked.sig[0]; |
| rcu_read_lock(); |
| prstatus->pr_ppid = task_pid_vnr(rcu_dereference(p->real_parent)); |
| rcu_read_unlock(); |
| prstatus->pr_pid = task_pid_vnr(p); |
| prstatus->pr_pgrp = task_pgrp_vnr(p); |
| prstatus->pr_sid = task_session_vnr(p); |
| if (thread_group_leader(p)) { |
| struct task_cputime cputime; |
| |
| /* |
| * This is the record for the group leader. It shows the |
| * group-wide total, not its individual thread total. |
| */ |
| thread_group_cputime(p, &cputime); |
| cputime_to_timeval(cputime.utime, &prstatus->pr_utime); |
| cputime_to_timeval(cputime.stime, &prstatus->pr_stime); |
| } else { |
| cputime_t utime, stime; |
| |
| task_cputime(p, &utime, &stime); |
| cputime_to_timeval(utime, &prstatus->pr_utime); |
| cputime_to_timeval(stime, &prstatus->pr_stime); |
| } |
| cputime_to_timeval(p->signal->cutime, &prstatus->pr_cutime); |
| cputime_to_timeval(p->signal->cstime, &prstatus->pr_cstime); |
| } |
| |
| static int fill_psinfo(struct elf_prpsinfo *psinfo, struct task_struct *p, |
| struct mm_struct *mm) |
| { |
| const struct cred *cred; |
| unsigned int i, len; |
| |
| /* first copy the parameters from user space */ |
| memset(psinfo, 0, sizeof(struct elf_prpsinfo)); |
| |
| len = mm->arg_end - mm->arg_start; |
| if (len >= ELF_PRARGSZ) |
| len = ELF_PRARGSZ-1; |
| if (copy_from_user(&psinfo->pr_psargs, |
| (const char __user *)mm->arg_start, len)) |
| return -EFAULT; |
| for(i = 0; i < len; i++) |
| if (psinfo->pr_psargs[i] == 0) |
| psinfo->pr_psargs[i] = ' '; |
| psinfo->pr_psargs[len] = 0; |
| |
| rcu_read_lock(); |
| psinfo->pr_ppid = task_pid_vnr(rcu_dereference(p->real_parent)); |
| rcu_read_unlock(); |
| psinfo->pr_pid = task_pid_vnr(p); |
| psinfo->pr_pgrp = task_pgrp_vnr(p); |
| psinfo->pr_sid = task_session_vnr(p); |
| |
| i = p->state ? ffz(~p->state) + 1 : 0; |
| psinfo->pr_state = i; |
| psinfo->pr_sname = (i > 5) ? '.' : "RSDTZW"[i]; |
| psinfo->pr_zomb = psinfo->pr_sname == 'Z'; |
| psinfo->pr_nice = task_nice(p); |
| psinfo->pr_flag = p->flags; |
| rcu_read_lock(); |
| cred = __task_cred(p); |
| SET_UID(psinfo->pr_uid, from_kuid_munged(cred->user_ns, cred->uid)); |
| SET_GID(psinfo->pr_gid, from_kgid_munged(cred->user_ns, cred->gid)); |
| rcu_read_unlock(); |
| strncpy(psinfo->pr_fname, p->comm, sizeof(psinfo->pr_fname)); |
| |
| return 0; |
| } |
| |
| static void fill_auxv_note(struct memelfnote *note, struct mm_struct *mm) |
| { |
| elf_addr_t *auxv = (elf_addr_t *) mm->saved_auxv; |
| int i = 0; |
| do |
| i += 2; |
| while (auxv[i - 2] != AT_NULL); |
| fill_note(note, "CORE", NT_AUXV, i * sizeof(elf_addr_t), auxv); |
| } |
| |
| static void fill_siginfo_note(struct memelfnote *note, user_siginfo_t *csigdata, |
| const siginfo_t *siginfo) |
| { |
| mm_segment_t old_fs = get_fs(); |
| set_fs(KERNEL_DS); |
| copy_siginfo_to_user((user_siginfo_t __user *) csigdata, siginfo); |
| set_fs(old_fs); |
| fill_note(note, "CORE", NT_SIGINFO, sizeof(*csigdata), csigdata); |
| } |
| |
| #define MAX_FILE_NOTE_SIZE (4*1024*1024) |
| /* |
| * Format of NT_FILE note: |
| * |
| * long count -- how many files are mapped |
| * long page_size -- units for file_ofs |
| * array of [COUNT] elements of |
| * long start |
| * long end |
| * long file_ofs |
| * followed by COUNT filenames in ASCII: "FILE1" NUL "FILE2" NUL... |
| */ |
| static int fill_files_note(struct memelfnote *note) |
| { |
| struct vm_area_struct *vma; |
| unsigned count, size, names_ofs, remaining, n; |
| user_long_t *data; |
| user_long_t *start_end_ofs; |
| char *name_base, *name_curpos; |
| |
| /* *Estimated* file count and total data size needed */ |
| count = current->mm->map_count; |
| size = count * 64; |
| |
| names_ofs = (2 + 3 * count) * sizeof(data[0]); |
| alloc: |
| if (size >= MAX_FILE_NOTE_SIZE) /* paranoia check */ |
| return -EINVAL; |
| size = round_up(size, PAGE_SIZE); |
| data = vmalloc(size); |
| if (!data) |
| return -ENOMEM; |
| |
| start_end_ofs = data + 2; |
| name_base = name_curpos = ((char *)data) + names_ofs; |
| remaining = size - names_ofs; |
| count = 0; |
| for (vma = current->mm->mmap; vma != NULL; vma = vma->vm_next) { |
| struct file *file; |
| const char *filename; |
| |
| file = vma->vm_file; |
| if (!file) |
| continue; |
| filename = file_path(file, name_curpos, remaining); |
| if (IS_ERR(filename)) { |
| if (PTR_ERR(filename) == -ENAMETOOLONG) { |
| vfree(data); |
| size = size * 5 / 4; |
| goto alloc; |
| } |
| continue; |
| } |
| |
| /* file_path() fills at the end, move name down */ |
| /* n = strlen(filename) + 1: */ |
| n = (name_curpos + remaining) - filename; |
| remaining = filename - name_curpos; |
| memmove(name_curpos, filename, n); |
| name_curpos += n; |
| |
| *start_end_ofs++ = vma->vm_start; |
| *start_end_ofs++ = vma->vm_end; |
| *start_end_ofs++ = vma->vm_pgoff; |
| count++; |
| } |
| |
| /* Now we know exact count of files, can store it */ |
| data[0] = count; |
| data[1] = PAGE_SIZE; |
| /* |
| * Count usually is less than current->mm->map_count, |
| * we need to move filenames down. |
| */ |
| n = current->mm->map_count - count; |
| if (n != 0) { |
| unsigned shift_bytes = n * 3 * sizeof(data[0]); |
| memmove(name_base - shift_bytes, name_base, |
| name_curpos - name_base); |
| name_curpos -= shift_bytes; |
| } |
| |
| size = name_curpos - (char *)data; |
| fill_note(note, "CORE", NT_FILE, size, data); |
| return 0; |
| } |
| |
| #ifdef CORE_DUMP_USE_REGSET |
| #include <linux/regset.h> |
| |
| struct elf_thread_core_info { |
| struct elf_thread_core_info *next; |
| struct task_struct *task; |
| struct elf_prstatus prstatus; |
| struct memelfnote notes[0]; |
| }; |
| |
| struct elf_note_info { |
| struct elf_thread_core_info *thread; |
| struct memelfnote psinfo; |
| struct memelfnote signote; |
| struct memelfnote auxv; |
| struct memelfnote files; |
| user_siginfo_t csigdata; |
| size_t size; |
| int thread_notes; |
| }; |
| |
| /* |
| * When a regset has a writeback hook, we call it on each thread before |
| * dumping user memory. On register window machines, this makes sure the |
| * user memory backing the register data is up to date before we read it. |
| */ |
| static void do_thread_regset_writeback(struct task_struct *task, |
| const struct user_regset *regset) |
| { |
| if (regset->writeback) |
| regset->writeback(task, regset, 1); |
| } |
| |
| #ifndef PR_REG_SIZE |
| #define PR_REG_SIZE(S) sizeof(S) |
| #endif |
| |
| #ifndef PRSTATUS_SIZE |
| #define PRSTATUS_SIZE(S) sizeof(S) |
| #endif |
| |
| #ifndef PR_REG_PTR |
| #define PR_REG_PTR(S) (&((S)->pr_reg)) |
| #endif |
| |
| #ifndef SET_PR_FPVALID |
| #define SET_PR_FPVALID(S, V) ((S)->pr_fpvalid = (V)) |
| #endif |
| |
| static int fill_thread_core_info(struct elf_thread_core_info *t, |
| const struct user_regset_view *view, |
| long signr, size_t *total) |
| { |
| unsigned int i; |
| |
| /* |
| * NT_PRSTATUS is the one special case, because the regset data |
| * goes into the pr_reg field inside the note contents, rather |
| * than being the whole note contents. We fill the reset in here. |
| * We assume that regset 0 is NT_PRSTATUS. |
| */ |
| fill_prstatus(&t->prstatus, t->task, signr); |
| (void) view->regsets[0].get(t->task, &view->regsets[0], |
| 0, PR_REG_SIZE(t->prstatus.pr_reg), |
| PR_REG_PTR(&t->prstatus), NULL); |
| |
| fill_note(&t->notes[0], "CORE", NT_PRSTATUS, |
| PRSTATUS_SIZE(t->prstatus), &t->prstatus); |
| *total += notesize(&t->notes[0]); |
| |
| do_thread_regset_writeback(t->task, &view->regsets[0]); |
| |
| /* |
| * Each other regset might generate a note too. For each regset |
| * that has no core_note_type or is inactive, we leave t->notes[i] |
| * all zero and we'll know to skip writing it later. |
| */ |
| for (i = 1; i < view->n; ++i) { |
| const struct user_regset *regset = &view->regsets[i]; |
| do_thread_regset_writeback(t->task, regset); |
| if (regset->core_note_type && regset->get && |
| (!regset->active || regset->active(t->task, regset))) { |
| int ret; |
| size_t size = regset->n * regset->size; |
| void *data = kmalloc(size, GFP_KERNEL); |
| if (unlikely(!data)) |
| return 0; |
| ret = regset->get(t->task, regset, |
| 0, size, data, NULL); |
| if (unlikely(ret)) |
| kfree(data); |
| else { |
| if (regset->core_note_type != NT_PRFPREG) |
| fill_note(&t->notes[i], "LINUX", |
| regset->core_note_type, |
| size, data); |
| else { |
| SET_PR_FPVALID(&t->prstatus, 1); |
| fill_note(&t->notes[i], "CORE", |
| NT_PRFPREG, size, data); |
| } |
| *total += notesize(&t->notes[i]); |
| } |
| } |
| } |
| |
| return 1; |
| } |
| |
| static int fill_note_info(struct elfhdr *elf, int phdrs, |
| struct elf_note_info *info, |
| const siginfo_t *siginfo, struct pt_regs *regs) |
| { |
| struct task_struct *dump_task = current; |
| const struct user_regset_view *view = task_user_regset_view(dump_task); |
| struct elf_thread_core_info *t; |
| struct elf_prpsinfo *psinfo; |
| struct core_thread *ct; |
| unsigned int i; |
| |
| info->size = 0; |
| info->thread = NULL; |
| |
| psinfo = kmalloc(sizeof(*psinfo), GFP_KERNEL); |
| if (psinfo == NULL) { |
| info->psinfo.data = NULL; /* So we don't free this wrongly */ |
| return 0; |
| } |
| |
| fill_note(&info->psinfo, "CORE", NT_PRPSINFO, sizeof(*psinfo), psinfo); |
| |
| /* |
| * Figure out how many notes we're going to need for each thread. |
| */ |
| info->thread_notes = 0; |
| for (i = 0; i < view->n; ++i) |
| if (view->regsets[i].core_note_type != 0) |
| ++info->thread_notes; |
| |
| /* |
| * Sanity check. We rely on regset 0 being in NT_PRSTATUS, |
| * since it is our one special case. |
| */ |
| if (unlikely(info->thread_notes == 0) || |
| unlikely(view->regsets[0].core_note_type != NT_PRSTATUS)) { |
| WARN_ON(1); |
| return 0; |
| } |
| |
| /* |
| * Initialize the ELF file header. |
| */ |
| fill_elf_header(elf, phdrs, |
| view->e_machine, view->e_flags); |
| |
| /* |
| * Allocate a structure for each thread. |
| */ |
| for (ct = &dump_task->mm->core_state->dumper; ct; ct = ct->next) { |
| t = kzalloc(offsetof(struct elf_thread_core_info, |
| notes[info->thread_notes]), |
| GFP_KERNEL); |
| if (unlikely(!t)) |
| return 0; |
| |
| t->task = ct->task; |
| if (ct->task == dump_task || !info->thread) { |
| t->next = info->thread; |
| info->thread = t; |
| } else { |
| /* |
| * Make sure to keep the original task at |
| * the head of the list. |
| */ |
| t->next = info->thread->next; |
| info->thread->next = t; |
| } |
| } |
| |
| /* |
| * Now fill in each thread's information. |
| */ |
| for (t = info->thread; t != NULL; t = t->next) |
| if (!fill_thread_core_info(t, view, siginfo->si_signo, &info->size)) |
| return 0; |
| |
| /* |
| * Fill in the two process-wide notes. |
| */ |
| fill_psinfo(psinfo, dump_task->group_leader, dump_task->mm); |
| info->size += notesize(&info->psinfo); |
| |
| fill_siginfo_note(&info->signote, &info->csigdata, siginfo); |
| info->size += notesize(&info->signote); |
| |
| fill_auxv_note(&info->auxv, current->mm); |
| info->size += notesize(&info->auxv); |
| |
| if (fill_files_note(&info->files) == 0) |
| info->size += notesize(&info->files); |
| |
| return 1; |
| } |
| |
| static size_t get_note_info_size(struct elf_note_info *info) |
| { |
| return info->size; |
| } |
| |
| /* |
| * Write all the notes for each thread. When writing the first thread, the |
| * process-wide notes are interleaved after the first thread-specific note. |
| */ |
| static int write_note_info(struct elf_note_info *info, |
| struct coredump_params *cprm) |
| { |
| bool first = true; |
| struct elf_thread_core_info *t = info->thread; |
| |
| do { |
| int i; |
| |
| if (!writenote(&t->notes[0], cprm)) |
| return 0; |
| |
| if (first && !writenote(&info->psinfo, cprm)) |
| return 0; |
| if (first && !writenote(&info->signote, cprm)) |
| return 0; |
| if (first && !writenote(&info->auxv, cprm)) |
| return 0; |
| if (first && info->files.data && |
| !writenote(&info->files, cprm)) |
| return 0; |
| |
| for (i = 1; i < info->thread_notes; ++i) |
| if (t->notes[i].data && |
| !writenote(&t->notes[i], cprm)) |
| return 0; |
| |
| first = false; |
| t = t->next; |
| } while (t); |
| |
| return 1; |
| } |
| |
| static void free_note_info(struct elf_note_info *info) |
| { |
| struct elf_thread_core_info *threads = info->thread; |
| while (threads) { |
| unsigned int i; |
| struct elf_thread_core_info *t = threads; |
| threads = t->next; |
| WARN_ON(t->notes[0].data && t->notes[0].data != &t->prstatus); |
| for (i = 1; i < info->thread_notes; ++i) |
| kfree(t->notes[i].data); |
| kfree(t); |
| } |
| kfree(info->psinfo.data); |
| vfree(info->files.data); |
| } |
| |
| #else |
| |
| /* Here is the structure in which status of each thread is captured. */ |
| struct elf_thread_status |
| { |
| struct list_head list; |
| struct elf_prstatus prstatus; /* NT_PRSTATUS */ |
| elf_fpregset_t fpu; /* NT_PRFPREG */ |
| struct task_struct *thread; |
| #ifdef ELF_CORE_COPY_XFPREGS |
| elf_fpxregset_t xfpu; /* ELF_CORE_XFPREG_TYPE */ |
| #endif |
| struct memelfnote notes[3]; |
| int num_notes; |
| }; |
| |
| /* |
| * In order to add the specific thread information for the elf file format, |
| * we need to keep a linked list of every threads pr_status and then create |
| * a single section for them in the final core file. |
| */ |
| static int elf_dump_thread_status(long signr, struct elf_thread_status *t) |
| { |
| int sz = 0; |
| struct task_struct *p = t->thread; |
| t->num_notes = 0; |
| |
| fill_prstatus(&t->prstatus, p, signr); |
| elf_core_copy_task_regs(p, &t->prstatus.pr_reg); |
| |
| fill_note(&t->notes[0], "CORE", NT_PRSTATUS, sizeof(t->prstatus), |
| &(t->prstatus)); |
| t->num_notes++; |
| sz += notesize(&t->notes[0]); |
| |
| if ((t->prstatus.pr_fpvalid = elf_core_copy_task_fpregs(p, NULL, |
| &t->fpu))) { |
| fill_note(&t->notes[1], "CORE", NT_PRFPREG, sizeof(t->fpu), |
| &(t->fpu)); |
| t->num_notes++; |
| sz += notesize(&t->notes[1]); |
| } |
| |
| #ifdef ELF_CORE_COPY_XFPREGS |
| if (elf_core_copy_task_xfpregs(p, &t->xfpu)) { |
| fill_note(&t->notes[2], "LINUX", ELF_CORE_XFPREG_TYPE, |
| sizeof(t->xfpu), &t->xfpu); |
| t->num_notes++; |
| sz += notesize(&t->notes[2]); |
| } |
| #endif |
| return sz; |
| } |
| |
| struct elf_note_info { |
| struct memelfnote *notes; |
| struct memelfnote *notes_files; |
| struct elf_prstatus *prstatus; /* NT_PRSTATUS */ |
| struct elf_prpsinfo *psinfo; /* NT_PRPSINFO */ |
| struct list_head thread_list; |
| elf_fpregset_t *fpu; |
| #ifdef ELF_CORE_COPY_XFPREGS |
| elf_fpxregset_t *xfpu; |
| #endif |
| user_siginfo_t csigdata; |
| int thread_status_size; |
| int numnote; |
| }; |
| |
| static int elf_note_info_init(struct elf_note_info *info) |
| { |
| memset(info, 0, sizeof(*info)); |
| INIT_LIST_HEAD(&info->thread_list); |
| |
| /* Allocate space for ELF notes */ |
| info->notes = kmalloc(8 * sizeof(struct memelfnote), GFP_KERNEL); |
| if (!info->notes) |
| return 0; |
| info->psinfo = kmalloc(sizeof(*info->psinfo), GFP_KERNEL); |
| if (!info->psinfo) |
| return 0; |
| info->prstatus = kmalloc(sizeof(*info->prstatus), GFP_KERNEL); |
| if (!info->prstatus) |
| return 0; |
| info->fpu = kmalloc(sizeof(*info->fpu), GFP_KERNEL); |
| if (!info->fpu) |
| return 0; |
| #ifdef ELF_CORE_COPY_XFPREGS |
| info->xfpu = kmalloc(sizeof(*info->xfpu), GFP_KERNEL); |
| if (!info->xfpu) |
| return 0; |
| #endif |
| return 1; |
| } |
| |
| static int fill_note_info(struct elfhdr *elf, int phdrs, |
| struct elf_note_info *info, |
| const siginfo_t *siginfo, struct pt_regs *regs) |
| { |
| struct list_head *t; |
| struct core_thread *ct; |
| struct elf_thread_status *ets; |
| |
| if (!elf_note_info_init(info)) |
| return 0; |
| |
| for (ct = current->mm->core_state->dumper.next; |
| ct; ct = ct->next) { |
| ets = kzalloc(sizeof(*ets), GFP_KERNEL); |
| if (!ets) |
| return 0; |
| |
| ets->thread = ct->task; |
| list_add(&ets->list, &info->thread_list); |
| } |
| |
| list_for_each(t, &info->thread_list) { |
| int sz; |
| |
| ets = list_entry(t, struct elf_thread_status, list); |
| sz = elf_dump_thread_status(siginfo->si_signo, ets); |
| info->thread_status_size += sz; |
| } |
| /* now collect the dump for the current */ |
| memset(info->prstatus, 0, sizeof(*info->prstatus)); |
| fill_prstatus(info->prstatus, current, siginfo->si_signo); |
| elf_core_copy_regs(&info->prstatus->pr_reg, regs); |
| |
| /* Set up header */ |
| fill_elf_header(elf, phdrs, ELF_ARCH, ELF_CORE_EFLAGS); |
| |
| /* |
| * Set up the notes in similar form to SVR4 core dumps made |
| * with info from their /proc. |
| */ |
| |
| fill_note(info->notes + 0, "CORE", NT_PRSTATUS, |
| sizeof(*info->prstatus), info->prstatus); |
| fill_psinfo(info->psinfo, current->group_leader, current->mm); |
| fill_note(info->notes + 1, "CORE", NT_PRPSINFO, |
| sizeof(*info->psinfo), info->psinfo); |
| |
| fill_siginfo_note(info->notes + 2, &info->csigdata, siginfo); |
| fill_auxv_note(info->notes + 3, current->mm); |
| info->numnote = 4; |
| |
| if (fill_files_note(info->notes + info->numnote) == 0) { |
| info->notes_files = info->notes + info->numnote; |
| info->numnote++; |
| } |
| |
| /* Try to dump the FPU. */ |
| info->prstatus->pr_fpvalid = elf_core_copy_task_fpregs(current, regs, |
| info->fpu); |
| if (info->prstatus->pr_fpvalid) |
| fill_note(info->notes + info->numnote++, |
| "CORE", NT_PRFPREG, sizeof(*info->fpu), info->fpu); |
| #ifdef ELF_CORE_COPY_XFPREGS |
| if (elf_core_copy_task_xfpregs(current, info->xfpu)) |
| fill_note(info->notes + info->numnote++, |
| "LINUX", ELF_CORE_XFPREG_TYPE, |
| sizeof(*info->xfpu), info->xfpu); |
| #endif |
| |
| return 1; |
| } |
| |
| static size_t get_note_info_size(struct elf_note_info *info) |
| { |
| int sz = 0; |
| int i; |
| |
| for (i = 0; i < info->numnote; i++) |
| sz += notesize(info->notes + i); |
| |
| sz += info->thread_status_size; |
| |
| return sz; |
| } |
| |
| static int write_note_info(struct elf_note_info *info, |
| struct coredump_params *cprm) |
| { |
| int i; |
| struct list_head *t; |
| |
| for (i = 0; i < info->numnote; i++) |
| if (!writenote(info->notes + i, cprm)) |
| return 0; |
| |
| /* write out the thread status notes section */ |
| list_for_each(t, &info->thread_list) { |
| struct elf_thread_status *tmp = |
| list_entry(t, struct elf_thread_status, list); |
| |
| for (i = 0; i < tmp->num_notes; i++) |
| if (!writenote(&tmp->notes[i], cprm)) |
| return 0; |
| } |
| |
| return 1; |
| } |
| |
| static void free_note_info(struct elf_note_info *info) |
| { |
| while (!list_empty(&info->thread_list)) { |
| struct list_head *tmp = info->thread_list.next; |
| list_del(tmp); |
| kfree(list_entry(tmp, struct elf_thread_status, list)); |
| } |
| |
| /* Free data possibly allocated by fill_files_note(): */ |
| if (info->notes_files) |
| vfree(info->notes_files->data); |
| |
| kfree(info->prstatus); |
| kfree(info->psinfo); |
| kfree(info->notes); |
| kfree(info->fpu); |
| #ifdef ELF_CORE_COPY_XFPREGS |
| kfree(info->xfpu); |
| #endif |
| } |
| |
| #endif |
| |
| static struct vm_area_struct *first_vma(struct task_struct *tsk, |
| struct vm_area_struct *gate_vma) |
| { |
| struct vm_area_struct *ret = tsk->mm->mmap; |
| |
| if (ret) |
| return ret; |
| return gate_vma; |
| } |
| /* |
| * Helper function for iterating across a vma list. It ensures that the caller |
| * will visit `gate_vma' prior to terminating the search. |
| */ |
| static struct vm_area_struct *next_vma(struct vm_area_struct *this_vma, |
| struct vm_area_struct *gate_vma) |
| { |
| struct vm_area_struct *ret; |
| |
| ret = this_vma->vm_next; |
| if (ret) |
| return ret; |
| if (this_vma == gate_vma) |
| return NULL; |
| return gate_vma; |
| } |
| |
| static void fill_extnum_info(struct elfhdr *elf, struct elf_shdr *shdr4extnum, |
| elf_addr_t e_shoff, int segs) |
| { |
| elf->e_shoff = e_shoff; |
| elf->e_shentsize = sizeof(*shdr4extnum); |
| elf->e_shnum = 1; |
| elf->e_shstrndx = SHN_UNDEF; |
| |
| memset(shdr4extnum, 0, sizeof(*shdr4extnum)); |
| |
| shdr4extnum->sh_type = SHT_NULL; |
| shdr4extnum->sh_size = elf->e_shnum; |
| shdr4extnum->sh_link = elf->e_shstrndx; |
| shdr4extnum->sh_info = segs; |
| } |
| |
| /* |
| * Actual dumper |
| * |
| * This is a two-pass process; first we find the offsets of the bits, |
| * and then they are actually written out. If we run out of core limit |
| * we just truncate. |
| */ |
| static int elf_core_dump(struct coredump_params *cprm) |
| { |
| int has_dumped = 0; |
| mm_segment_t fs; |
| int segs, i; |
| size_t vma_data_size = 0; |
| struct vm_area_struct *vma, *gate_vma; |
| struct elfhdr *elf = NULL; |
| loff_t offset = 0, dataoff; |
| struct elf_note_info info = { }; |
| struct elf_phdr *phdr4note = NULL; |
| struct elf_shdr *shdr4extnum = NULL; |
| Elf_Half e_phnum; |
| elf_addr_t e_shoff; |
| elf_addr_t *vma_filesz = NULL; |
| |
| /* |
| * We no longer stop all VM operations. |
| * |
| * This is because those proceses that could possibly change map_count |
| * or the mmap / vma pages are now blocked in do_exit on current |
| * finishing this core dump. |
| * |
| * Only ptrace can touch these memory addresses, but it doesn't change |
| * the map_count or the pages allocated. So no possibility of crashing |
| * exists while dumping the mm->vm_next areas to the core file. |
| */ |
| |
| /* alloc memory for large data structures: too large to be on stack */ |
| elf = kmalloc(sizeof(*elf), GFP_KERNEL); |
| if (!elf) |
| goto out; |
| /* |
| * The number of segs are recored into ELF header as 16bit value. |
| * Please check DEFAULT_MAX_MAP_COUNT definition when you modify here. |
| */ |
| segs = current->mm->map_count; |
| segs += elf_core_extra_phdrs(); |
| |
| gate_vma = get_gate_vma(current->mm); |
| if (gate_vma != NULL) |
| segs++; |
| |
| /* for notes section */ |
| segs++; |
| |
| /* If segs > PN_XNUM(0xffff), then e_phnum overflows. To avoid |
| * this, kernel supports extended numbering. Have a look at |
| * include/linux/elf.h for further information. */ |
| e_phnum = segs > PN_XNUM ? PN_XNUM : segs; |
| |
| /* |
| * Collect all the non-memory information about the process for the |
| * notes. This also sets up the file header. |
| */ |
| if (!fill_note_info(elf, e_phnum, &info, cprm->siginfo, cprm->regs)) |
| goto cleanup; |
| |
| has_dumped = 1; |
| |
| fs = get_fs(); |
| set_fs(KERNEL_DS); |
| |
| offset += sizeof(*elf); /* Elf header */ |
| offset += segs * sizeof(struct elf_phdr); /* Program headers */ |
| |
| /* Write notes phdr entry */ |
| { |
| size_t sz = get_note_info_size(&info); |
| |
| sz += elf_coredump_extra_notes_size(); |
| |
| phdr4note = kmalloc(sizeof(*phdr4note), GFP_KERNEL); |
| if (!phdr4note) |
| goto end_coredump; |
| |
| fill_elf_note_phdr(phdr4note, sz, offset); |
| offset += sz; |
| } |
| |
| dataoff = offset = roundup(offset, ELF_EXEC_PAGESIZE); |
| |
| vma_filesz = kmalloc_array(segs - 1, sizeof(*vma_filesz), GFP_KERNEL); |
| if (!vma_filesz) |
| goto end_coredump; |
| |
| for (i = 0, vma = first_vma(current, gate_vma); vma != NULL; |
| vma = next_vma(vma, gate_vma)) { |
| unsigned long dump_size; |
| |
| dump_size = vma_dump_size(vma, cprm->mm_flags); |
| vma_filesz[i++] = dump_size; |
| vma_data_size += dump_size; |
| } |
| |
| offset += vma_data_size; |
| offset += elf_core_extra_data_size(); |
| e_shoff = offset; |
| |
| if (e_phnum == PN_XNUM) { |
| shdr4extnum = kmalloc(sizeof(*shdr4extnum), GFP_KERNEL); |
| if (!shdr4extnum) |
| goto end_coredump; |
| fill_extnum_info(elf, shdr4extnum, e_shoff, segs); |
| } |
| |
| offset = dataoff; |
| |
| if (!dump_emit(cprm, elf, sizeof(*elf))) |
| goto end_coredump; |
| |
| if (!dump_emit(cprm, phdr4note, sizeof(*phdr4note))) |
| goto end_coredump; |
| |
| /* Write program headers for segments dump */ |
| for (i = 0, vma = first_vma(current, gate_vma); vma != NULL; |
| vma = next_vma(vma, gate_vma)) { |
| struct elf_phdr phdr; |
| |
| phdr.p_type = PT_LOAD; |
| phdr.p_offset = offset; |
| phdr.p_vaddr = vma->vm_start; |
| phdr.p_paddr = 0; |
| phdr.p_filesz = vma_filesz[i++]; |
| phdr.p_memsz = vma->vm_end - vma->vm_start; |
| offset += phdr.p_filesz; |
| phdr.p_flags = vma->vm_flags & VM_READ ? PF_R : 0; |
| if (vma->vm_flags & VM_WRITE) |
| phdr.p_flags |= PF_W; |
| if (vma->vm_flags & VM_EXEC) |
| phdr.p_flags |= PF_X; |
| phdr.p_align = ELF_EXEC_PAGESIZE; |
| |
| if (!dump_emit(cprm, &phdr, sizeof(phdr))) |
| goto end_coredump; |
| } |
| |
| if (!elf_core_write_extra_phdrs(cprm, offset)) |
| goto end_coredump; |
| |
| /* write out the notes section */ |
| if (!write_note_info(&info, cprm)) |
| goto end_coredump; |
| |
| if (elf_coredump_extra_notes_write(cprm)) |
| goto end_coredump; |
| |
| /* Align to page */ |
| if (!dump_skip(cprm, dataoff - cprm->file->f_pos)) |
| goto end_coredump; |
| |
| for (i = 0, vma = first_vma(current, gate_vma); vma != NULL; |
| vma = next_vma(vma, gate_vma)) { |
| unsigned long addr; |
| unsigned long end; |
| |
| end = vma->vm_start + vma_filesz[i++]; |
| |
| for (addr = vma->vm_start; addr < end; addr += PAGE_SIZE) { |
| struct page *page; |
| int stop; |
| |
| page = get_dump_page(addr); |
| if (page) { |
| void *kaddr = kmap(page); |
| stop = !dump_emit(cprm, kaddr, PAGE_SIZE); |
| kunmap(page); |
| page_cache_release(page); |
| } else |
| stop = !dump_skip(cprm, PAGE_SIZE); |
| if (stop) |
| goto end_coredump; |
| } |
| } |
| |
| if (!elf_core_write_extra_data(cprm)) |
| goto end_coredump; |
| |
| if (e_phnum == PN_XNUM) { |
| if (!dump_emit(cprm, shdr4extnum, sizeof(*shdr4extnum))) |
| goto end_coredump; |
| } |
| |
| end_coredump: |
| set_fs(fs); |
| |
| cleanup: |
| free_note_info(&info); |
| kfree(shdr4extnum); |
| kfree(vma_filesz); |
| kfree(phdr4note); |
| kfree(elf); |
| out: |
| return has_dumped; |
| } |
| |
| #endif /* CONFIG_ELF_CORE */ |
| |
| static int __init init_elf_binfmt(void) |
| { |
| register_binfmt(&elf_format); |
| return 0; |
| } |
| |
| static void __exit exit_elf_binfmt(void) |
| { |
| /* Remove the COFF and ELF loaders. */ |
| unregister_binfmt(&elf_format); |
| } |
| |
| core_initcall(init_elf_binfmt); |
| module_exit(exit_elf_binfmt); |
| MODULE_LICENSE("GPL"); |