diff options
author | Ralf Baechle <ralf@linux-mips.org> | 1997-01-07 02:33:00 +0000 |
---|---|---|
committer | <ralf@linux-mips.org> | 1997-01-07 02:33:00 +0000 |
commit | beb116954b9b7f3bb56412b2494b562f02b864b1 (patch) | |
tree | 120e997879884e1b9d93b265221b939d2ef1ade1 /fs/binfmt_aout.c | |
parent | 908d4681a1dc3792ecafbe64265783a86c4cccb6 (diff) |
Import of Linux/MIPS 2.1.14
Diffstat (limited to 'fs/binfmt_aout.c')
-rw-r--r-- | fs/binfmt_aout.c | 507 |
1 files changed, 507 insertions, 0 deletions
diff --git a/fs/binfmt_aout.c b/fs/binfmt_aout.c new file mode 100644 index 000000000..cb535656a --- /dev/null +++ b/fs/binfmt_aout.c @@ -0,0 +1,507 @@ +/* + * linux/fs/binfmt_aout.c + * + * Copyright (C) 1991, 1992, 1996 Linus Torvalds + */ + +#include <linux/module.h> + +#include <linux/fs.h> +#include <linux/sched.h> +#include <linux/kernel.h> +#include <linux/mm.h> +#include <linux/mman.h> +#include <linux/a.out.h> +#include <linux/errno.h> +#include <linux/signal.h> +#include <linux/string.h> +#include <linux/stat.h> +#include <linux/fcntl.h> +#include <linux/ptrace.h> +#include <linux/user.h> +#include <linux/malloc.h> +#include <linux/binfmts.h> +#include <linux/personality.h> + +#include <asm/system.h> +#include <asm/uaccess.h> +#include <asm/pgtable.h> + +static int load_aout_binary(struct linux_binprm *, struct pt_regs * regs); +static int load_aout_library(int fd); +static int aout_core_dump(long signr, struct pt_regs * regs); + +extern void dump_thread(struct pt_regs *, struct user *); + +static struct linux_binfmt aout_format = { +#ifndef MODULE + NULL, NULL, load_aout_binary, load_aout_library, aout_core_dump +#else + NULL, &mod_use_count_, load_aout_binary, load_aout_library, aout_core_dump +#endif +}; + +static void set_brk(unsigned long start, unsigned long end) +{ + start = PAGE_ALIGN(start); + end = PAGE_ALIGN(end); + if (end <= start) + return; + do_mmap(NULL, start, end - start, + PROT_READ | PROT_WRITE | PROT_EXEC, + MAP_FIXED | MAP_PRIVATE, 0); +} + +/* + * These are the only things you should do on a core-file: use only these + * macros to write out all the necessary info. + */ +#define DUMP_WRITE(addr,nr) \ +while (file.f_op->write(inode,&file,(char *)(addr),(nr)) != (nr)) goto close_coredump + +#define DUMP_SEEK(offset) \ +if (file.f_op->llseek) { \ + if (file.f_op->llseek(inode,&file,(offset),0) != (offset)) \ + goto close_coredump; \ +} else file.f_pos = (offset) + +/* + * Routine writes a core dump image in the current directory. + * Currently only a stub-function. + * + * Note that setuid/setgid files won't make a core-dump if the uid/gid + * changed due to the set[u|g]id. It's enforced by the "current->dumpable" + * field, which also makes sure the core-dumps won't be recursive if the + * dumping of the process results in another error.. + */ + +static inline int +do_aout_core_dump(long signr, struct pt_regs * regs) +{ + struct inode * inode = NULL; + struct file file; + unsigned short fs; + int has_dumped = 0; + char corefile[6+sizeof(current->comm)]; + unsigned long dump_start, dump_size; + struct user dump; +#ifdef __alpha__ +# define START_DATA(u) (u.start_data) +#else +# define START_DATA(u) (u.u_tsize << PAGE_SHIFT) +#endif + + if (!current->dumpable || current->mm->count != 1) + return 0; + current->dumpable = 0; + +/* See if we have enough room to write the upage. */ + if (current->rlim[RLIMIT_CORE].rlim_cur < PAGE_SIZE) + return 0; + fs = get_fs(); + set_fs(KERNEL_DS); + memcpy(corefile,"core.",5); +#if 0 + memcpy(corefile+5,current->comm,sizeof(current->comm)); +#else + corefile[4] = '\0'; +#endif + if (open_namei(corefile,O_CREAT | 2 | O_TRUNC,0600,&inode,NULL)) { + inode = NULL; + goto end_coredump; + } + if (!S_ISREG(inode->i_mode)) + goto end_coredump; + if (!inode->i_op || !inode->i_op->default_file_ops) + goto end_coredump; + if (get_write_access(inode)) + goto end_coredump; + file.f_mode = 3; + file.f_flags = 0; + file.f_count = 1; + file.f_inode = inode; + file.f_pos = 0; + file.f_reada = 0; + file.f_op = inode->i_op->default_file_ops; + if (file.f_op->open) + if (file.f_op->open(inode,&file)) + goto done_coredump; + if (!file.f_op->write) + goto close_coredump; + has_dumped = 1; + current->flags |= PF_DUMPCORE; + strncpy(dump.u_comm, current->comm, sizeof(current->comm)); + dump.u_ar0 = (void *)(((unsigned long)(&dump.regs)) - ((unsigned long)(&dump))); + dump.signal = signr; + dump_thread(regs, &dump); + +/* If the size of the dump file exceeds the rlimit, then see what would happen + if we wrote the stack, but not the data area. */ + if ((dump.u_dsize+dump.u_ssize+1) * PAGE_SIZE > + current->rlim[RLIMIT_CORE].rlim_cur) + dump.u_dsize = 0; + +/* Make sure we have enough room to write the stack and data areas. */ + if ((dump.u_ssize+1) * PAGE_SIZE > + current->rlim[RLIMIT_CORE].rlim_cur) + dump.u_ssize = 0; + +/* make sure we actually have a data and stack area to dump */ + set_fs(USER_DS); + if (verify_area(VERIFY_READ, (void *) START_DATA(dump), dump.u_dsize << PAGE_SHIFT)) + dump.u_dsize = 0; + if (verify_area(VERIFY_READ, (void *) dump.start_stack, dump.u_ssize << PAGE_SHIFT)) + dump.u_ssize = 0; + + set_fs(KERNEL_DS); +/* struct user */ + DUMP_WRITE(&dump,sizeof(dump)); +/* Now dump all of the user data. Include malloced stuff as well */ + DUMP_SEEK(PAGE_SIZE); +/* now we start writing out the user space info */ + set_fs(USER_DS); +/* Dump the data area */ + if (dump.u_dsize != 0) { + dump_start = START_DATA(dump); + dump_size = dump.u_dsize << PAGE_SHIFT; + DUMP_WRITE(dump_start,dump_size); + } +/* Now prepare to dump the stack area */ + if (dump.u_ssize != 0) { + dump_start = dump.start_stack; + dump_size = dump.u_ssize << PAGE_SHIFT; + DUMP_WRITE(dump_start,dump_size); + } +/* Finally dump the task struct. Not be used by gdb, but could be useful */ + set_fs(KERNEL_DS); + DUMP_WRITE(current,sizeof(*current)); +close_coredump: + if (file.f_op->release) + file.f_op->release(inode,&file); +done_coredump: + put_write_access(inode); +end_coredump: + set_fs(fs); + iput(inode); + return has_dumped; +} + +static int +aout_core_dump(long signr, struct pt_regs * regs) +{ + int retval; + + MOD_INC_USE_COUNT; + retval = do_aout_core_dump(signr, regs); + MOD_DEC_USE_COUNT; + return retval; +} + +/* + * create_aout_tables() parses the env- and arg-strings in new user + * memory and creates the pointer tables from them, and puts their + * addresses on the "stack", returning the new stack pointer value. + */ +static unsigned long * create_aout_tables(char * p, struct linux_binprm * bprm) +{ + char **argv, **envp; + unsigned long * sp; + int argc = bprm->argc; + int envc = bprm->envc; + + sp = (unsigned long *) ((-(unsigned long)sizeof(char *)) & (unsigned long) p); +#ifdef __alpha__ +/* whee.. test-programs are so much fun. */ + put_user(0, --sp); + put_user(0, --sp); + if (bprm->loader) { + put_user(0, --sp); + put_user(0x3eb, --sp); + put_user(bprm->loader, --sp); + put_user(0x3ea, --sp); + } + put_user(bprm->exec, --sp); + put_user(0x3e9, --sp); +#endif + sp -= envc+1; + envp = (char **) sp; + sp -= argc+1; + argv = (char **) sp; +#if defined(__i386__) || defined(__mc68000__) + put_user((unsigned long) envp,--sp); + put_user((unsigned long) argv,--sp); +#endif + put_user(argc,--sp); + current->mm->arg_start = (unsigned long) p; + while (argc-->0) { + char c; + put_user(p,argv++); + do { + get_user(c,p++); + } while (c); + } + put_user(NULL,argv); + current->mm->arg_end = current->mm->env_start = (unsigned long) p; + while (envc-->0) { + char c; + put_user(p,envp++); + do { + get_user(c,p++); + } while (c); + } + put_user(NULL,envp); + current->mm->env_end = (unsigned long) p; + return sp; +} + +/* + * These are the functions used to load a.out style executables and shared + * libraries. There is no binary dependent code anywhere else. + */ + +static inline int +do_load_aout_binary(struct linux_binprm * bprm, struct pt_regs * regs) +{ + struct exec ex; + struct file * file; + int fd; + unsigned long error; + unsigned long p = bprm->p; + unsigned long fd_offset; + unsigned long rlim; + + ex = *((struct exec *) bprm->buf); /* exec-header */ + if ((N_MAGIC(ex) != ZMAGIC && N_MAGIC(ex) != OMAGIC && + N_MAGIC(ex) != QMAGIC) || + N_TRSIZE(ex) || N_DRSIZE(ex) || + bprm->inode->i_size < ex.a_text+ex.a_data+N_SYMSIZE(ex)+N_TXTOFF(ex)) { + return -ENOEXEC; + } + + current->personality = PER_LINUX; + fd_offset = N_TXTOFF(ex); + +#ifdef __i386__ + if (N_MAGIC(ex) == ZMAGIC && fd_offset != BLOCK_SIZE) { + printk(KERN_NOTICE "N_TXTOFF != BLOCK_SIZE. See a.out.h.\n"); + return -ENOEXEC; + } + + if (N_MAGIC(ex) == ZMAGIC && ex.a_text && + (fd_offset < bprm->inode->i_sb->s_blocksize)) { + printk(KERN_NOTICE "N_TXTOFF < BLOCK_SIZE. Please convert binary.\n"); + return -ENOEXEC; + } +#endif + + /* Check initial limits. This avoids letting people circumvent + * size limits imposed on them by creating programs with large + * arrays in the data or bss. + */ + rlim = current->rlim[RLIMIT_DATA].rlim_cur; + if (rlim >= RLIM_INFINITY) + rlim = ~0; + if (ex.a_data + ex.a_bss > rlim) + return -ENOMEM; + + /* OK, This is the point of no return */ + flush_old_exec(bprm); + + current->mm->end_code = ex.a_text + + (current->mm->start_code = N_TXTADDR(ex)); + current->mm->end_data = ex.a_data + + (current->mm->start_data = N_DATADDR(ex)); + current->mm->brk = ex.a_bss + + (current->mm->start_brk = N_BSSADDR(ex)); + + current->mm->rss = 0; + current->mm->mmap = NULL; + current->suid = current->euid = current->fsuid = bprm->e_uid; + current->sgid = current->egid = current->fsgid = bprm->e_gid; + current->flags &= ~PF_FORKNOEXEC; + if (N_MAGIC(ex) == OMAGIC) { +#ifdef __alpha__ + do_mmap(NULL, N_TXTADDR(ex) & PAGE_MASK, + ex.a_text+ex.a_data + PAGE_SIZE - 1, + PROT_READ|PROT_WRITE|PROT_EXEC, + MAP_FIXED|MAP_PRIVATE, 0); + read_exec(bprm->inode, fd_offset, (char *) N_TXTADDR(ex), + ex.a_text+ex.a_data, 0); +#else + do_mmap(NULL, 0, ex.a_text+ex.a_data, + PROT_READ|PROT_WRITE|PROT_EXEC, + MAP_FIXED|MAP_PRIVATE, 0); + read_exec(bprm->inode, 32, (char *) 0, ex.a_text+ex.a_data, 0); +#endif + } else { + if (ex.a_text & 0xfff || ex.a_data & 0xfff) + printk(KERN_NOTICE "executable not page aligned\n"); + + fd = open_inode(bprm->inode, O_RDONLY); + + if (fd < 0) + return fd; + file = current->files->fd[fd]; + if (!file->f_op || !file->f_op->mmap) { + sys_close(fd); + do_mmap(NULL, 0, ex.a_text+ex.a_data, + PROT_READ|PROT_WRITE|PROT_EXEC, + MAP_FIXED|MAP_PRIVATE, 0); + read_exec(bprm->inode, fd_offset, + (char *) N_TXTADDR(ex), ex.a_text+ex.a_data, 0); + goto beyond_if; + } + + error = do_mmap(file, N_TXTADDR(ex), ex.a_text, + PROT_READ | PROT_EXEC, + MAP_FIXED | MAP_PRIVATE | MAP_DENYWRITE | MAP_EXECUTABLE, + fd_offset); + + if (error != N_TXTADDR(ex)) { + sys_close(fd); + send_sig(SIGKILL, current, 0); + return error; + } + + error = do_mmap(file, N_DATADDR(ex), ex.a_data, + PROT_READ | PROT_WRITE | PROT_EXEC, + MAP_FIXED | MAP_PRIVATE | MAP_DENYWRITE | MAP_EXECUTABLE, + fd_offset + ex.a_text); + sys_close(fd); + if (error != N_DATADDR(ex)) { + send_sig(SIGKILL, current, 0); + return error; + } + } +beyond_if: + if (current->exec_domain && current->exec_domain->use_count) + (*current->exec_domain->use_count)--; + if (current->binfmt && current->binfmt->use_count) + (*current->binfmt->use_count)--; + current->exec_domain = lookup_exec_domain(current->personality); + current->binfmt = &aout_format; + if (current->exec_domain && current->exec_domain->use_count) + (*current->exec_domain->use_count)++; + if (current->binfmt && current->binfmt->use_count) + (*current->binfmt->use_count)++; + + set_brk(current->mm->start_brk, current->mm->brk); + + p = setup_arg_pages(p, bprm); + + p = (unsigned long) create_aout_tables((char *)p, bprm); + current->mm->start_stack = p; +#ifdef __alpha__ + regs->gp = ex.a_gpvalue; +#endif + start_thread(regs, ex.a_entry, p); + if (current->flags & PF_PTRACED) + send_sig(SIGTRAP, current, 0); + return 0; +} + +static int +load_aout_binary(struct linux_binprm * bprm, struct pt_regs * regs) +{ + int retval; + + MOD_INC_USE_COUNT; + retval = do_load_aout_binary(bprm, regs); + MOD_DEC_USE_COUNT; + return retval; +} + +static inline int +do_load_aout_library(int fd) +{ + struct file * file; + struct exec ex; + struct inode * inode; + unsigned int len; + unsigned int bss; + unsigned int start_addr; + unsigned long error; + + file = current->files->fd[fd]; + inode = file->f_inode; + + if (!file || !file->f_op) + return -EACCES; + + /* Seek into the file */ + if (file->f_op->llseek) { + if ((error = file->f_op->llseek(inode, file, 0, 0)) != 0) + return -ENOEXEC; + } else + file->f_pos = 0; + + set_fs(KERNEL_DS); + error = file->f_op->read(inode, file, (char *) &ex, sizeof(ex)); + set_fs(USER_DS); + if (error != sizeof(ex)) + return -ENOEXEC; + + /* We come in here for the regular a.out style of shared libraries */ + if ((N_MAGIC(ex) != ZMAGIC && N_MAGIC(ex) != QMAGIC) || N_TRSIZE(ex) || + N_DRSIZE(ex) || ((ex.a_entry & 0xfff) && N_MAGIC(ex) == ZMAGIC) || + inode->i_size < ex.a_text+ex.a_data+N_SYMSIZE(ex)+N_TXTOFF(ex)) { + return -ENOEXEC; + } + if (N_MAGIC(ex) == ZMAGIC && N_TXTOFF(ex) && + (N_TXTOFF(ex) < inode->i_sb->s_blocksize)) { + printk("N_TXTOFF < BLOCK_SIZE. Please convert library\n"); + return -ENOEXEC; + } + + if (N_FLAGS(ex)) return -ENOEXEC; + + /* For QMAGIC, the starting address is 0x20 into the page. We mask + this off to get the starting address for the page */ + + start_addr = ex.a_entry & 0xfffff000; + + /* Now use mmap to map the library into memory. */ + error = do_mmap(file, start_addr, ex.a_text + ex.a_data, + PROT_READ | PROT_WRITE | PROT_EXEC, + MAP_FIXED | MAP_PRIVATE | MAP_DENYWRITE, + N_TXTOFF(ex)); + if (error != start_addr) + return error; + len = PAGE_ALIGN(ex.a_text + ex.a_data); + bss = ex.a_text + ex.a_data + ex.a_bss; + if (bss > len) { + error = do_mmap(NULL, start_addr + len, bss-len, + PROT_READ|PROT_WRITE|PROT_EXEC, + MAP_PRIVATE|MAP_FIXED, 0); + if (error != start_addr + len) + return error; + } + return 0; +} + +static int +load_aout_library(int fd) +{ + int retval; + + MOD_INC_USE_COUNT; + retval = do_load_aout_library(fd); + MOD_DEC_USE_COUNT; + return retval; +} + + +int init_aout_binfmt(void) { + return register_binfmt(&aout_format); +} + +#ifdef MODULE +int init_module(void) { + return init_aout_binfmt(); +} + +void cleanup_module( void) { + unregister_binfmt(&aout_format); +} +#endif + |