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author | 2005-04-16 15:20:36 -0700 | |
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committer | 2005-04-16 15:20:36 -0700 | |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /fs/binfmt_elf.c | |
download | linux-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.gz linux-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.bz2 linux-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.zip |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'fs/binfmt_elf.c')
-rw-r--r-- | fs/binfmt_elf.c | 1677 |
1 files changed, 1677 insertions, 0 deletions
diff --git a/fs/binfmt_elf.c b/fs/binfmt_elf.c new file mode 100644 index 000000000000..76ec9d8939ff --- /dev/null +++ b/fs/binfmt_elf.c @@ -0,0 +1,1677 @@ +/* + * 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/stat.h> +#include <linux/time.h> +#include <linux/mm.h> +#include <linux/mman.h> +#include <linux/a.out.h> +#include <linux/errno.h> +#include <linux/signal.h> +#include <linux/binfmts.h> +#include <linux/string.h> +#include <linux/file.h> +#include <linux/fcntl.h> +#include <linux/ptrace.h> +#include <linux/slab.h> +#include <linux/shm.h> +#include <linux/personality.h> +#include <linux/elfcore.h> +#include <linux/init.h> +#include <linux/highuid.h> +#include <linux/smp.h> +#include <linux/smp_lock.h> +#include <linux/compiler.h> +#include <linux/highmem.h> +#include <linux/pagemap.h> +#include <linux/security.h> +#include <linux/syscalls.h> +#include <linux/random.h> + +#include <asm/uaccess.h> +#include <asm/param.h> +#include <asm/page.h> + +#include <linux/elf.h> + +static int load_elf_binary(struct linux_binprm * bprm, struct pt_regs * regs); +static int load_elf_library(struct file*); +static unsigned long elf_map (struct file *, unsigned long, struct elf_phdr *, int, int); +extern int dump_fpu (struct pt_regs *, elf_fpregset_t *); + +#ifndef elf_addr_t +#define elf_addr_t unsigned long +#endif + +/* + * If we don't support core dumping, then supply a NULL so we + * don't even try. + */ +#ifdef USE_ELF_CORE_DUMP +static int elf_core_dump(long signr, struct pt_regs * regs, struct file * file); +#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; + down_write(¤t->mm->mmap_sem); + addr = do_brk(start, end - start); + up_write(¤t->mm->mmap_sem); + 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 litle 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 + +static int +create_elf_tables(struct linux_binprm *bprm, struct elfhdr * exec, + int interp_aout, 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; + const char *k_platform = ELF_PLATFORM; + int items; + elf_addr_t *elf_info; + int ei_index = 0; + struct task_struct *tsk = current; + + /* + * 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; + + /* + * 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); + + u_platform = (elf_addr_t __user *)STACK_ALLOC(p, len); + if (__copy_to_user(u_platform, k_platform, len)) + return -EFAULT; + } + + /* Create the ELF interpreter info */ + elf_info = (elf_addr_t *) current->mm->saved_auxv; +#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. + */ + 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, (elf_addr_t) tsk->uid); + NEW_AUX_ENT(AT_EUID, (elf_addr_t) tsk->euid); + NEW_AUX_ENT(AT_GID, (elf_addr_t) tsk->gid); + NEW_AUX_ENT(AT_EGID, (elf_addr_t) tsk->egid); + NEW_AUX_ENT(AT_SECURE, (elf_addr_t) security_bprm_secureexec(bprm)); + if (k_platform) { + NEW_AUX_ENT(AT_PLATFORM, (elf_addr_t)(unsigned long)u_platform); + } + if (bprm->interp_flags & BINPRM_FLAGS_EXECFD) { + NEW_AUX_ENT(AT_EXECFD, (elf_addr_t) 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); + if (interp_aout) { + items += 3; /* a.out interpreters require argv & envp too */ + } else { + items += 1; /* ELF interpreters only put argc on the stack */ + } + 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 + + /* Now, let's put argc (and argv, envp if appropriate) on the stack */ + if (__put_user(argc, sp++)) + return -EFAULT; + if (interp_aout) { + argv = sp + 2; + envp = argv + argc + 1; + __put_user((elf_addr_t)(unsigned long)argv, sp++); + __put_user((elf_addr_t)(unsigned long)envp, sp++); + } else { + argv = sp; + envp = argv + argc + 1; + } + + /* Populate argv and envp */ + p = current->mm->arg_start; + while (argc-- > 0) { + size_t len; + __put_user((elf_addr_t)p, argv++); + len = strnlen_user((void __user *)p, PAGE_SIZE*MAX_ARG_PAGES); + if (!len || len > PAGE_SIZE*MAX_ARG_PAGES) + return 0; + p += len; + } + if (__put_user(0, argv)) + return -EFAULT; + current->mm->arg_end = current->mm->env_start = p; + while (envc-- > 0) { + size_t len; + __put_user((elf_addr_t)p, envp++); + len = strnlen_user((void __user *)p, PAGE_SIZE*MAX_ARG_PAGES); + if (!len || len > PAGE_SIZE*MAX_ARG_PAGES) + return 0; + 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 map_addr; + + down_write(¤t->mm->mmap_sem); + map_addr = do_mmap(filep, ELF_PAGESTART(addr), + eppnt->p_filesz + ELF_PAGEOFFSET(eppnt->p_vaddr), prot, type, + eppnt->p_offset - ELF_PAGEOFFSET(eppnt->p_vaddr)); + up_write(¤t->mm->mmap_sem); + return(map_addr); +} + +#endif /* !elf_map */ + +/* 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_load_addr) +{ + struct elf_phdr *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; + int retval, i, size; + + /* 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 || !interpreter->f_op->mmap) + goto out; + + /* + * If the size of this structure has changed, then punt, since + * we will be doing the wrong thing. + */ + if (interp_elf_ex->e_phentsize != sizeof(struct elf_phdr)) + goto out; + if (interp_elf_ex->e_phnum < 1 || + interp_elf_ex->e_phnum > 65536U / sizeof(struct elf_phdr)) + goto out; + + /* Now read in all of the header information */ + + size = sizeof(struct elf_phdr) * interp_elf_ex->e_phnum; + if (size > ELF_MIN_ALIGN) + goto out; + elf_phdata = (struct elf_phdr *) kmalloc(size, GFP_KERNEL); + if (!elf_phdata) + goto out; + + retval = kernel_read(interpreter,interp_elf_ex->e_phoff,(char *)elf_phdata,size); + error = -EIO; + if (retval != size) { + if (retval < 0) + error = retval; + goto out_close; + } + + eppnt = 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; + + map_addr = elf_map(interpreter, load_addr + vaddr, eppnt, elf_prot, elf_type); + error = map_addr; + if (BAD_ADDR(map_addr)) + goto out_close; + + 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 is only necessary to check p_memsz. + */ + k = load_addr + eppnt->p_vaddr; + if (k > TASK_SIZE || eppnt->p_filesz > eppnt->p_memsz || + eppnt->p_memsz > TASK_SIZE || TASK_SIZE - eppnt->p_memsz < k) { + error = -ENOMEM; + goto out_close; + } + + /* + * 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; + } + } + + /* + * 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_close; + } + + elf_bss = ELF_PAGESTART(elf_bss + ELF_MIN_ALIGN - 1); /* What we have mapped so far */ + + /* Map the last of the bss segment */ + if (last_bss > elf_bss) { + down_write(¤t->mm->mmap_sem); + error = do_brk(elf_bss, last_bss - elf_bss); + up_write(¤t->mm->mmap_sem); + if (BAD_ADDR(error)) + goto out_close; + } + + *interp_load_addr = load_addr; + error = ((unsigned long) interp_elf_ex->e_entry) + load_addr; + +out_close: + kfree(elf_phdata); +out: + return error; +} + +static unsigned long load_aout_interp(struct exec * interp_ex, + struct file * interpreter) +{ + unsigned long text_data, elf_entry = ~0UL; + char __user * addr; + loff_t offset; + + current->mm->end_code = interp_ex->a_text; + text_data = interp_ex->a_text + interp_ex->a_data; + current->mm->end_data = text_data; + current->mm->brk = interp_ex->a_bss + text_data; + + switch (N_MAGIC(*interp_ex)) { + case OMAGIC: + offset = 32; + addr = (char __user *)0; + break; + case ZMAGIC: + case QMAGIC: + offset = N_TXTOFF(*interp_ex); + addr = (char __user *) N_TXTADDR(*interp_ex); + break; + default: + goto out; + } + + down_write(¤t->mm->mmap_sem); + do_brk(0, text_data); + up_write(¤t->mm->mmap_sem); + if (!interpreter->f_op || !interpreter->f_op->read) + goto out; + if (interpreter->f_op->read(interpreter, addr, text_data, &offset) < 0) + goto out; + flush_icache_range((unsigned long)addr, + (unsigned long)addr + text_data); + + + down_write(¤t->mm->mmap_sem); + do_brk(ELF_PAGESTART(text_data + ELF_MIN_ALIGN - 1), + interp_ex->a_bss); + up_write(¤t->mm->mmap_sem); + elf_entry = interp_ex->a_entry; + +out: + return elf_entry; +} + +/* + * These are the functions used to load ELF style executables and shared + * libraries. There is no binary dependent code anywhere else. + */ + +#define INTERPRETER_NONE 0 +#define INTERPRETER_AOUT 1 +#define INTERPRETER_ELF 2 + + +static unsigned long randomize_stack_top(unsigned long stack_top) +{ + unsigned int random_variable = 0; + + if (current->flags & PF_RANDOMIZE) + random_variable = get_random_int() % (8*1024*1024); +#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 pt_regs * regs) +{ + 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 int interpreter_type = INTERPRETER_NONE; + unsigned char ibcs2_interpreter = 0; + unsigned long error; + struct elf_phdr * elf_ppnt, *elf_phdata; + unsigned long elf_bss, elf_brk; + int elf_exec_fileno; + int retval, i; + unsigned int size; + unsigned long elf_entry, interp_load_addr = 0; + unsigned long start_code, end_code, start_data, end_data; + unsigned long reloc_func_desc = 0; + char passed_fileno[6]; + struct files_struct *files; + int have_pt_gnu_stack, executable_stack = EXSTACK_DEFAULT; + unsigned long def_flags = 0; + struct { + struct elfhdr elf_ex; + struct elfhdr interp_elf_ex; + struct exec interp_ex; + } *loc; + + 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||!bprm->file->f_op->mmap) + goto out; + + /* Now read in all of the header information */ + + if (loc->elf_ex.e_phentsize != sizeof(struct elf_phdr)) + goto out; + if (loc->elf_ex.e_phnum < 1 || + loc->elf_ex.e_phnum > 65536U / sizeof(struct elf_phdr)) + goto out; + size = loc->elf_ex.e_phnum * sizeof(struct elf_phdr); + retval = -ENOMEM; + elf_phdata = (struct elf_phdr *) kmalloc(size, GFP_KERNEL); + if (!elf_phdata) + goto out; + + retval = kernel_read(bprm->file, loc->elf_ex.e_phoff, (char *) elf_phdata, size); + if (retval != size) { + if (retval >= 0) + retval = -EIO; + goto out_free_ph; + } + + files = current->files; /* Refcounted so ok */ + retval = unshare_files(); + if (retval < 0) + goto out_free_ph; + if (files == current->files) { + put_files_struct(files); + files = NULL; + } + + /* exec will make our files private anyway, but for the a.out + loader stuff we need to do it earlier */ + + retval = get_unused_fd(); + if (retval < 0) + goto out_free_fh; + get_file(bprm->file); + fd_install(elf_exec_fileno = retval, bprm->file); + + 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_file; + + retval = -ENOMEM; + elf_interpreter = (char *) kmalloc(elf_ppnt->p_filesz, + GFP_KERNEL); + if (!elf_interpreter) + goto out_free_file; + + 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; + + /* If the program interpreter is one of these two, + * then assume an iBCS2 image. Otherwise assume + * a native linux image. + */ + if (strcmp(elf_interpreter,"/usr/lib/libc.so.1") == 0 || + strcmp(elf_interpreter,"/usr/lib/ld.so.1") == 0) + ibcs2_interpreter = 1; + + /* + * The early SET_PERSONALITY here is so that the lookup + * for the interpreter happens in the namespace of the + * to-be-execed image. SET_PERSONALITY can select an + * alternate root. + * + * However, SET_PERSONALITY is NOT allowed to switch + * this task into the new images's memory mapping + * policy - that is, TASK_SIZE must still evaluate to + * that which is appropriate to the execing application. + * This is because exit_mmap() needs to have TASK_SIZE + * evaluate to the size of the old image. + * + * So if (say) a 64-bit application is execing a 32-bit + * application it is the architecture's responsibility + * to defer changing the value of TASK_SIZE until the + * switch really is going to happen - do this in + * flush_thread(). - akpm + */ + SET_PERSONALITY(loc->elf_ex, ibcs2_interpreter); + + interpreter = open_exec(elf_interpreter); + retval = PTR_ERR(interpreter); + if (IS_ERR(interpreter)) + goto out_free_interp; + retval = kernel_read(interpreter, 0, bprm->buf, BINPRM_BUF_SIZE); + if (retval != BINPRM_BUF_SIZE) { + if (retval >= 0) + retval = -EIO; + goto out_free_dentry; + } + + /* Get the exec headers */ + loc->interp_ex = *((struct exec *) bprm->buf); + loc->interp_elf_ex = *((struct elfhdr *) bprm->buf); + break; + } + elf_ppnt++; + } + + elf_ppnt = elf_phdata; + for (i = 0; i < loc->elf_ex.e_phnum; i++, elf_ppnt++) + if (elf_ppnt->p_type == PT_GNU_STACK) { + if (elf_ppnt->p_flags & PF_X) + executable_stack = EXSTACK_ENABLE_X; + else + executable_stack = EXSTACK_DISABLE_X; + break; + } + have_pt_gnu_stack = (i < loc->elf_ex.e_phnum); + + /* Some simple consistency checks for the interpreter */ + if (elf_interpreter) { + interpreter_type = INTERPRETER_ELF | INTERPRETER_AOUT; + + /* Now figure out which format our binary is */ + if ((N_MAGIC(loc->interp_ex) != OMAGIC) && + (N_MAGIC(loc->interp_ex) != ZMAGIC) && + (N_MAGIC(loc->interp_ex) != QMAGIC)) + interpreter_type = INTERPRETER_ELF; + + if (memcmp(loc->interp_elf_ex.e_ident, ELFMAG, SELFMAG) != 0) + interpreter_type &= ~INTERPRETER_ELF; + + retval = -ELIBBAD; + if (!interpreter_type) + goto out_free_dentry; + + /* Make sure only one type was selected */ + if ((interpreter_type & INTERPRETER_ELF) && + interpreter_type != INTERPRETER_ELF) { + // FIXME - ratelimit this before re-enabling + // printk(KERN_WARNING "ELF: Ambiguous type, using ELF\n"); + interpreter_type = INTERPRETER_ELF; + } + /* Verify the interpreter has a valid arch */ + if ((interpreter_type == INTERPRETER_ELF) && + !elf_check_arch(&loc->interp_elf_ex)) + goto out_free_dentry; + } else { + /* Executables without an interpreter also need a personality */ + SET_PERSONALITY(loc->elf_ex, ibcs2_interpreter); + } + + /* OK, we are done with that, now set up the arg stuff, + and then start this sucker up */ + + if ((!bprm->sh_bang) && (interpreter_type == INTERPRETER_AOUT)) { + char *passed_p = passed_fileno; + sprintf(passed_fileno, "%d", elf_exec_fileno); + + if (elf_interpreter) { + retval = copy_strings_kernel(1, &passed_p, bprm); + if (retval) + goto out_free_dentry; + bprm->argc++; + } + } + + /* Flush all traces of the currently running executable */ + retval = flush_old_exec(bprm); + if (retval) + goto out_free_dentry; + + /* Discard our unneeded old files struct */ + if (files) { + steal_locks(files); + put_files_struct(files); + files = NULL; + } + + /* OK, This is the point of no return */ + current->mm->start_data = 0; + current->mm->end_data = 0; + current->mm->end_code = 0; + current->mm->mmap = NULL; + current->flags &= ~PF_FORKNOEXEC; + current->mm->def_flags = def_flags; + + /* Do this immediately, since STACK_TOP as used in setup_arg_pages + may depend on the personality. */ + SET_PERSONALITY(loc->elf_ex, ibcs2_interpreter); + 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; + arch_pick_mmap_layout(current->mm); + + /* Do this so that we can load the interpreter, if need be. We will + change some of these later */ + set_mm_counter(current->mm, rss, 0); + current->mm->free_area_cache = current->mm->mmap_base; + retval = setup_arg_pages(bprm, randomize_stack_top(STACK_TOP), + executable_stack); + if (retval < 0) { + send_sig(SIGKILL, current, 0); + goto out_free_dentry; + } + +#ifdef ARCH_HAS_SETUP_ADDITIONAL_PAGES + retval = arch_setup_additional_pages(bprm, executable_stack); + if (retval < 0) { + send_sig(SIGKILL, current, 0); + goto out_free_dentry; + } +#endif /* ARCH_HAS_SETUP_ADDITIONAL_PAGES */ + + current->mm->start_stack = bprm->p; + + /* Now we do a little grungy work by mmaping the ELF image into + the correct location in memory. At this point, we assume that + the image should be loaded at fixed address, not at a variable + address. */ + + 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; + + 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) { + send_sig(SIGKILL, current, 0); + 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_PAGESTART(ELF_ET_DYN_BASE - vaddr); + } + + error = elf_map(bprm->file, load_bias + vaddr, elf_ppnt, elf_prot, elf_flags); + if (BAD_ADDR(error)) { + send_sig(SIGKILL, current, 0); + 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 (k > TASK_SIZE || 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. */ + send_sig(SIGKILL, current, 0); + 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) { + send_sig(SIGKILL, current, 0); + goto out_free_dentry; + } + if (padzero(elf_bss)) { + send_sig(SIGSEGV, current, 0); + retval = -EFAULT; /* Nobody gets to see this, but.. */ + goto out_free_dentry; + } + + if (elf_interpreter) { + if (interpreter_type == INTERPRETER_AOUT) + elf_entry = load_aout_interp(&loc->interp_ex, + interpreter); + else + elf_entry = load_elf_interp(&loc->interp_elf_ex, + interpreter, + &interp_load_addr); + if (BAD_ADDR(elf_entry)) { + printk(KERN_ERR "Unable to load interpreter %.128s\n", + elf_interpreter); + force_sig(SIGSEGV, current); + retval = -ENOEXEC; /* Nobody gets to see this, but.. */ + 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; + } + + kfree(elf_phdata); + + if (interpreter_type != INTERPRETER_AOUT) + sys_close(elf_exec_fileno); + + set_binfmt(&elf_format); + + compute_creds(bprm); + current->flags &= ~PF_FORKNOEXEC; + create_elf_tables(bprm, &loc->elf_ex, (interpreter_type == INTERPRETER_AOUT), + load_addr, interp_load_addr); + /* N.B. passed_fileno might not be initialized? */ + if (interpreter_type == INTERPRETER_AOUT) + current->mm->arg_start += strlen(passed_fileno) + 1; + 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->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. */ + down_write(¤t->mm->mmap_sem); + error = do_mmap(NULL, 0, PAGE_SIZE, PROT_READ | PROT_EXEC, + MAP_FIXED | MAP_PRIVATE, 0); + up_write(¤t->mm->mmap_sem); + } + +#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); + if (unlikely(current->ptrace & PT_PTRACED)) { + if (current->ptrace & PT_TRACE_EXEC) + ptrace_notify ((PTRACE_EVENT_EXEC << 8) | SIGTRAP); + else + send_sig(SIGTRAP, current, 0); + } + retval = 0; +out: + kfree(loc); +out_ret: + return retval; + + /* error cleanup */ +out_free_dentry: + allow_write_access(interpreter); + if (interpreter) + fput(interpreter); +out_free_interp: + if (elf_interpreter) + kfree(elf_interpreter); +out_free_file: + sys_close(elf_exec_fileno); +out_free_fh: + if (files) { + put_files_struct(current->files); + current->files = files; + } +out_free_ph: + kfree(elf_phdata); + goto out; +} + +/* 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 || !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. */ + down_write(¤t->mm->mmap_sem); + error = do_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))); + up_write(¤t->mm->mmap_sem); + 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) { + down_write(¤t->mm->mmap_sem); + do_brk(len, bss - len); + up_write(¤t->mm->mmap_sem); + } + error = 0; + +out_free_ph: + kfree(elf_phdata); +out: + return error; +} + +/* + * Note that some platforms still use traditional core dumps and not + * the ELF core dump. Each platform can select it as appropriate. + */ +#ifdef USE_ELF_CORE_DUMP + +/* + * ELF core dumper + * + * Modelled on fs/exec.c:aout_core_dump() + * Jeremy Fitzhardinge <jeremy@sw.oz.au> + */ +/* + * These are the only things you should do on a core-file: use only these + * functions to write out all the necessary info. + */ +static int dump_write(struct file *file, const void *addr, int nr) +{ + return file->f_op->write(file, addr, nr, &file->f_pos) == nr; +} + +static int dump_seek(struct file *file, off_t off) +{ + if (file->f_op->llseek) { + if (file->f_op->llseek(file, off, 0) != off) + return 0; + } else + file->f_pos = off; + return 1; +} + +/* + * Decide whether a segment is worth dumping; default is yes to be + * sure (missing info is worse than too much; etc). + * Personally I'd include everything, and use the coredump limit... + * + * I think we should skip something. But I am not sure how. H.J. + */ +static int maydump(struct vm_area_struct *vma) +{ + /* Do not dump I/O mapped devices or special mappings */ + if (vma->vm_flags & (VM_IO | VM_RESERVED)) + return 0; + + /* Dump shared memory only if mapped from an anonymous file. */ + if (vma->vm_flags & VM_SHARED) + return vma->vm_file->f_dentry->d_inode->i_nlink == 0; + + /* If it hasn't been written to, don't write it out */ + if (!vma->anon_vma) + return 0; + + return 1; +} + +#define roundup(x, y) ((((x)+((y)-1))/(y))*(y)) + +/* 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; +} + +#define DUMP_WRITE(addr, nr) \ + do { if (!dump_write(file, (addr), (nr))) return 0; } while(0) +#define DUMP_SEEK(off) \ + do { if (!dump_seek(file, (off))) return 0; } while(0) + +static int writenote(struct memelfnote *men, struct file *file) +{ + struct elf_note en; + + en.n_namesz = strlen(men->name) + 1; + en.n_descsz = men->datasz; + en.n_type = men->type; + + DUMP_WRITE(&en, sizeof(en)); + DUMP_WRITE(men->name, en.n_namesz); + /* XXX - cast from long long to long to avoid need for libgcc.a */ + DUMP_SEEK(roundup((unsigned long)file->f_pos, 4)); /* XXX */ + DUMP_WRITE(men->data, men->datasz); + DUMP_SEEK(roundup((unsigned long)file->f_pos, 4)); /* XXX */ + + return 1; +} +#undef DUMP_WRITE +#undef DUMP_SEEK + +#define DUMP_WRITE(addr, nr) \ + if ((size += (nr)) > limit || !dump_write(file, (addr), (nr))) \ + goto end_coredump; +#define DUMP_SEEK(off) \ + if (!dump_seek(file, (off))) \ + goto end_coredump; + +static inline void fill_elf_header(struct elfhdr *elf, int segs) +{ + 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; + memset(elf->e_ident+EI_PAD, 0, EI_NIDENT-EI_PAD); + + elf->e_type = ET_CORE; + elf->e_machine = ELF_ARCH; + elf->e_version = EV_CURRENT; + elf->e_entry = 0; + elf->e_phoff = sizeof(struct elfhdr); + elf->e_shoff = 0; + elf->e_flags = ELF_CORE_EFLAGS; + elf->e_ehsize = sizeof(struct elfhdr); + elf->e_phentsize = sizeof(struct elf_phdr); + elf->e_phnum = segs; + elf->e_shentsize = 0; + elf->e_shnum = 0; + elf->e_shstrndx = 0; + return; +} + +static inline void fill_elf_note_phdr(struct elf_phdr *phdr, int sz, off_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]; + prstatus->pr_pid = p->pid; + prstatus->pr_ppid = p->parent->pid; + prstatus->pr_pgrp = process_group(p); + prstatus->pr_sid = p->signal->session; + if (thread_group_leader(p)) { + /* + * This is the record for the group leader. Add in the + * cumulative times of previous dead threads. This total + * won't include the time of each live thread whose state + * is included in the core dump. The final total reported + * to our parent process when it calls wait4 will include + * those sums as well as the little bit more time it takes + * this and each other thread to finish dying after the + * core dump synchronization phase. + */ + cputime_to_timeval(cputime_add(p->utime, p->signal->utime), + &prstatus->pr_utime); + cputime_to_timeval(cputime_add(p->stime, p->signal->stime), + &prstatus->pr_stime); + } else { + cputime_to_timeval(p->utime, &prstatus->pr_utime); + cputime_to_timeval(p->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) +{ + 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; + + psinfo->pr_pid = p->pid; + psinfo->pr_ppid = p->parent->pid; + psinfo->pr_pgrp = process_group(p); + psinfo->pr_sid = p->signal->session; + + i = p->state ? ffz(~p->state) + 1 : 0; + psinfo->pr_state = i; + psinfo->pr_sname = (i < 0 || i > 5) ? '.' : "RSDTZW"[i]; + psinfo->pr_zomb = psinfo->pr_sname == 'Z'; + psinfo->pr_nice = task_nice(p); + psinfo->pr_flag = p->flags; + SET_UID(psinfo->pr_uid, p->uid); + SET_GID(psinfo->pr_gid, p->gid); + strncpy(psinfo->pr_fname, p->comm, sizeof(psinfo->pr_fname)); + + return 0; +} + +/* 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; /* NT_PRXFPREG */ +#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", NT_PRXFPREG, sizeof(t->xfpu), &t->xfpu); + t->num_notes++; + sz += notesize(&t->notes[2]); + } +#endif + return sz; +} + +/* + * 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(long signr, struct pt_regs * regs, struct file * file) +{ +#define NUM_NOTES 6 + int has_dumped = 0; + mm_segment_t fs; + int segs; + size_t size = 0; + int i; + struct vm_area_struct *vma; + struct elfhdr *elf = NULL; + off_t offset = 0, dataoff; + unsigned long limit = current->signal->rlim[RLIMIT_CORE].rlim_cur; + int numnote; + struct memelfnote *notes = NULL; + struct elf_prstatus *prstatus = NULL; /* NT_PRSTATUS */ + struct elf_prpsinfo *psinfo = NULL; /* NT_PRPSINFO */ + struct task_struct *g, *p; + LIST_HEAD(thread_list); + struct list_head *t; + elf_fpregset_t *fpu = NULL; +#ifdef ELF_CORE_COPY_XFPREGS + elf_fpxregset_t *xfpu = NULL; +#endif + int thread_status_size = 0; + elf_addr_t *auxv; + + /* + * 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 cleanup; + prstatus = kmalloc(sizeof(*prstatus), GFP_KERNEL); + if (!prstatus) + goto cleanup; + psinfo = kmalloc(sizeof(*psinfo), GFP_KERNEL); + if (!psinfo) + goto cleanup; + notes = kmalloc(NUM_NOTES * sizeof(struct memelfnote), GFP_KERNEL); + if (!notes) + goto cleanup; + fpu = kmalloc(sizeof(*fpu), GFP_KERNEL); + if (!fpu) + goto cleanup; +#ifdef ELF_CORE_COPY_XFPREGS + xfpu = kmalloc(sizeof(*xfpu), GFP_KERNEL); + if (!xfpu) + goto cleanup; +#endif + + if (signr) { + struct elf_thread_status *tmp; + read_lock(&tasklist_lock); + do_each_thread(g,p) + if (current->mm == p->mm && current != p) { + tmp = kmalloc(sizeof(*tmp), GFP_ATOMIC); + if (!tmp) { + read_unlock(&tasklist_lock); + goto cleanup; + } + memset(tmp, 0, sizeof(*tmp)); + INIT_LIST_HEAD(&tmp->list); + tmp->thread = p; + list_add(&tmp->list, &thread_list); + } + while_each_thread(g,p); + read_unlock(&tasklist_lock); + list_for_each(t, &thread_list) { + struct elf_thread_status *tmp; + int sz; + + tmp = list_entry(t, struct elf_thread_status, list); + sz = elf_dump_thread_status(signr, tmp); + thread_status_size += sz; + } + } + /* now collect the dump for the current */ + memset(prstatus, 0, sizeof(*prstatus)); + fill_prstatus(prstatus, current, signr); + elf_core_copy_regs(&prstatus->pr_reg, regs); + + segs = current->mm->map_count; +#ifdef ELF_CORE_EXTRA_PHDRS + segs += ELF_CORE_EXTRA_PHDRS; +#endif + + /* Set up header */ + fill_elf_header(elf, segs+1); /* including notes section */ + + has_dumped = 1; + current->flags |= PF_DUMPCORE; + + /* + * Set up the notes in similar form to SVR4 core dumps made + * with info from their /proc. + */ + + fill_note(notes +0, "CORE", NT_PRSTATUS, sizeof(*prstatus), prstatus); + + fill_psinfo(psinfo, current->group_leader, current->mm); + fill_note(notes +1, "CORE", NT_PRPSINFO, sizeof(*psinfo), psinfo); + + fill_note(notes +2, "CORE", NT_TASKSTRUCT, sizeof(*current), current); + + numnote = 3; + + auxv = (elf_addr_t *) current->mm->saved_auxv; + + i = 0; + do + i += 2; + while (auxv[i - 2] != AT_NULL); + fill_note(¬es[numnote++], "CORE", NT_AUXV, + i * sizeof (elf_addr_t), auxv); + + /* Try to dump the FPU. */ + if ((prstatus->pr_fpvalid = elf_core_copy_task_fpregs(current, regs, fpu))) + fill_note(notes + numnote++, + "CORE", NT_PRFPREG, sizeof(*fpu), fpu); +#ifdef ELF_CORE_COPY_XFPREGS + if (elf_core_copy_task_xfpregs(current, xfpu)) + fill_note(notes + numnote++, + "LINUX", NT_PRXFPREG, sizeof(*xfpu), xfpu); +#endif + + fs = get_fs(); + set_fs(KERNEL_DS); + + DUMP_WRITE(elf, sizeof(*elf)); + offset += sizeof(*elf); /* Elf header */ + offset += (segs+1) * sizeof(struct elf_phdr); /* Program headers */ + + /* Write notes phdr entry */ + { + struct elf_phdr phdr; + int sz = 0; + + for (i = 0; i < numnote; i++) + sz += notesize(notes + i); + + sz += thread_status_size; + + fill_elf_note_phdr(&phdr, sz, offset); + offset += sz; + DUMP_WRITE(&phdr, sizeof(phdr)); + } + + /* Page-align dumped data */ + dataoff = offset = roundup(offset, ELF_EXEC_PAGESIZE); + + /* Write program headers for segments dump */ + for (vma = current->mm->mmap; vma != NULL; vma = vma->vm_next) { + struct elf_phdr phdr; + size_t sz; + + sz = vma->vm_end - vma->vm_start; + + phdr.p_type = PT_LOAD; + phdr.p_offset = offset; + phdr.p_vaddr = vma->vm_start; + phdr.p_paddr = 0; + phdr.p_filesz = maydump(vma) ? sz : 0; + phdr.p_memsz = sz; + 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; + + DUMP_WRITE(&phdr, sizeof(phdr)); + } + +#ifdef ELF_CORE_WRITE_EXTRA_PHDRS + ELF_CORE_WRITE_EXTRA_PHDRS; +#endif + + /* write out the notes section */ + for (i = 0; i < numnote; i++) + if (!writenote(notes + i, file)) + goto end_coredump; + + /* write out the thread status notes section */ + list_for_each(t, &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], file)) + goto end_coredump; + } + + DUMP_SEEK(dataoff); + + for (vma = current->mm->mmap; vma != NULL; vma = vma->vm_next) { + unsigned long addr; + + if (!maydump(vma)) + continue; + + for (addr = vma->vm_start; + addr < vma->vm_end; + addr += PAGE_SIZE) { + struct page* page; + struct vm_area_struct *vma; + + if (get_user_pages(current, current->mm, addr, 1, 0, 1, + &page, &vma) <= 0) { + DUMP_SEEK (file->f_pos + PAGE_SIZE); + } else { + if (page == ZERO_PAGE(addr)) { + DUMP_SEEK (file->f_pos + PAGE_SIZE); + } else { + void *kaddr; + flush_cache_page(vma, addr, page_to_pfn(page)); + kaddr = kmap(page); + if ((size += PAGE_SIZE) > limit || + !dump_write(file, kaddr, + PAGE_SIZE)) { + kunmap(page); + page_cache_release(page); + goto end_coredump; + } + kunmap(page); + } + page_cache_release(page); + } + } + } + +#ifdef ELF_CORE_WRITE_EXTRA_DATA + ELF_CORE_WRITE_EXTRA_DATA; +#endif + + if ((off_t) file->f_pos != offset) { + /* Sanity check */ + printk("elf_core_dump: file->f_pos (%ld) != offset (%ld)\n", + (off_t) file->f_pos, offset); + } + +end_coredump: + set_fs(fs); + +cleanup: + while(!list_empty(&thread_list)) { + struct list_head *tmp = thread_list.next; + list_del(tmp); + kfree(list_entry(tmp, struct elf_thread_status, list)); + } + + kfree(elf); + kfree(prstatus); + kfree(psinfo); + kfree(notes); + kfree(fpu); +#ifdef ELF_CORE_COPY_XFPREGS + kfree(xfpu); +#endif + return has_dumped; +#undef NUM_NOTES +} + +#endif /* USE_ELF_CORE_DUMP */ + +static int __init init_elf_binfmt(void) +{ + return register_binfmt(&elf_format); +} + +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"); |