From 57f0f512b273f60d52568b8c6b77e17f5636edc0 Mon Sep 17 00:00:00 2001 From: André Fabian Silva Delgado Date: Wed, 5 Aug 2015 17:04:01 -0300 Subject: Initial import --- arch/x86/ia32/ia32_aout.c | 479 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 479 insertions(+) create mode 100644 arch/x86/ia32/ia32_aout.c (limited to 'arch/x86/ia32/ia32_aout.c') diff --git a/arch/x86/ia32/ia32_aout.c b/arch/x86/ia32/ia32_aout.c new file mode 100644 index 000000000..ae6aad1d2 --- /dev/null +++ b/arch/x86/ia32/ia32_aout.c @@ -0,0 +1,479 @@ +/* + * a.out loader for x86-64 + * + * Copyright (C) 1991, 1992, 1996 Linus Torvalds + * Hacked together by Andi Kleen + */ + +#include + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include +#include +#include +#include + +#undef WARN_OLD + +static int load_aout_binary(struct linux_binprm *); +static int load_aout_library(struct file *); + +#ifdef CONFIG_COREDUMP +static int aout_core_dump(struct coredump_params *); + +static unsigned long get_dr(int n) +{ + struct perf_event *bp = current->thread.ptrace_bps[n]; + return bp ? bp->hw.info.address : 0; +} + +/* + * fill in the user structure for a core dump.. + */ +static void dump_thread32(struct pt_regs *regs, struct user32 *dump) +{ + u32 fs, gs; + memset(dump, 0, sizeof(*dump)); + +/* changed the size calculations - should hopefully work better. lbt */ + dump->magic = CMAGIC; + dump->start_code = 0; + dump->start_stack = regs->sp & ~(PAGE_SIZE - 1); + dump->u_tsize = ((unsigned long) current->mm->end_code) >> PAGE_SHIFT; + dump->u_dsize = ((unsigned long) + (current->mm->brk + (PAGE_SIZE-1))) >> PAGE_SHIFT; + dump->u_dsize -= dump->u_tsize; + dump->u_debugreg[0] = get_dr(0); + dump->u_debugreg[1] = get_dr(1); + dump->u_debugreg[2] = get_dr(2); + dump->u_debugreg[3] = get_dr(3); + dump->u_debugreg[6] = current->thread.debugreg6; + dump->u_debugreg[7] = current->thread.ptrace_dr7; + + if (dump->start_stack < 0xc0000000) { + unsigned long tmp; + + tmp = (unsigned long) (0xc0000000 - dump->start_stack); + dump->u_ssize = tmp >> PAGE_SHIFT; + } + + dump->regs.ebx = regs->bx; + dump->regs.ecx = regs->cx; + dump->regs.edx = regs->dx; + dump->regs.esi = regs->si; + dump->regs.edi = regs->di; + dump->regs.ebp = regs->bp; + dump->regs.eax = regs->ax; + dump->regs.ds = current->thread.ds; + dump->regs.es = current->thread.es; + savesegment(fs, fs); + dump->regs.fs = fs; + savesegment(gs, gs); + dump->regs.gs = gs; + dump->regs.orig_eax = regs->orig_ax; + dump->regs.eip = regs->ip; + dump->regs.cs = regs->cs; + dump->regs.eflags = regs->flags; + dump->regs.esp = regs->sp; + dump->regs.ss = regs->ss; + +#if 1 /* FIXME */ + dump->u_fpvalid = 0; +#else + dump->u_fpvalid = dump_fpu(regs, &dump->i387); +#endif +} + +#endif + +static struct linux_binfmt aout_format = { + .module = THIS_MODULE, + .load_binary = load_aout_binary, + .load_shlib = load_aout_library, +#ifdef CONFIG_COREDUMP + .core_dump = aout_core_dump, +#endif + .min_coredump = PAGE_SIZE +}; + +static void set_brk(unsigned long start, unsigned long end) +{ + start = PAGE_ALIGN(start); + end = PAGE_ALIGN(end); + if (end <= start) + return; + vm_brk(start, end - start); +} + +#ifdef CONFIG_COREDUMP +/* + * These are the only things you should do on a core-file: use only these + * macros to write out all the necessary info. + */ + +#include + +#define START_DATA(u) (u.u_tsize << PAGE_SHIFT) +#define START_STACK(u) (u.start_stack) + +/* + * 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->mm->dumpable" + * field, which also makes sure the core-dumps won't be recursive if the + * dumping of the process results in another error.. + */ + +static int aout_core_dump(struct coredump_params *cprm) +{ + mm_segment_t fs; + int has_dumped = 0; + unsigned long dump_start, dump_size; + struct user32 dump; + + fs = get_fs(); + set_fs(KERNEL_DS); + has_dumped = 1; + strncpy(dump.u_comm, current->comm, sizeof(current->comm)); + dump.u_ar0 = offsetof(struct user32, regs); + dump.signal = cprm->siginfo->si_signo; + dump_thread32(cprm->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 > cprm->limit) + dump.u_dsize = 0; + + /* Make sure we have enough room to write the stack and data areas. */ + if ((dump.u_ssize + 1) * PAGE_SIZE > cprm->limit) + dump.u_ssize = 0; + + /* make sure we actually have a data and stack area to dump */ + set_fs(USER_DS); + if (!access_ok(VERIFY_READ, (void *) (unsigned long)START_DATA(dump), + dump.u_dsize << PAGE_SHIFT)) + dump.u_dsize = 0; + if (!access_ok(VERIFY_READ, (void *) (unsigned long)START_STACK(dump), + dump.u_ssize << PAGE_SHIFT)) + dump.u_ssize = 0; + + set_fs(KERNEL_DS); + /* struct user */ + if (!dump_emit(cprm, &dump, sizeof(dump))) + goto end_coredump; + /* Now dump all of the user data. Include malloced stuff as well */ + if (!dump_skip(cprm, PAGE_SIZE - sizeof(dump))) + goto end_coredump; + /* 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; + if (!dump_emit(cprm, (void *)dump_start, dump_size)) + goto end_coredump; + } + /* Now prepare to dump the stack area */ + if (dump.u_ssize != 0) { + dump_start = START_STACK(dump); + dump_size = dump.u_ssize << PAGE_SHIFT; + if (!dump_emit(cprm, (void *)dump_start, dump_size)) + goto end_coredump; + } +end_coredump: + set_fs(fs); + return has_dumped; +} +#endif + +/* + * 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 u32 __user *create_aout_tables(char __user *p, struct linux_binprm *bprm) +{ + u32 __user *argv, *envp, *sp; + int argc = bprm->argc, envc = bprm->envc; + + sp = (u32 __user *) ((-(unsigned long)sizeof(u32)) & (unsigned long) p); + sp -= envc+1; + envp = sp; + sp -= argc+1; + argv = sp; + put_user((unsigned long) envp, --sp); + put_user((unsigned long) argv, --sp); + put_user(argc, --sp); + current->mm->arg_start = (unsigned long) p; + while (argc-- > 0) { + char c; + + put_user((u32)(unsigned long)p, argv++); + do { + get_user(c, p++); + } while (c); + } + put_user(0, argv); + current->mm->arg_end = current->mm->env_start = (unsigned long) p; + while (envc-- > 0) { + char c; + + put_user((u32)(unsigned long)p, envp++); + do { + get_user(c, p++); + } while (c); + } + put_user(0, 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 int load_aout_binary(struct linux_binprm *bprm) +{ + unsigned long error, fd_offset, rlim; + struct pt_regs *regs = current_pt_regs(); + struct exec ex; + int retval; + + ex = *((struct exec *) bprm->buf); /* exec-header */ + if ((N_MAGIC(ex) != ZMAGIC && N_MAGIC(ex) != OMAGIC && + N_MAGIC(ex) != QMAGIC && N_MAGIC(ex) != NMAGIC) || + N_TRSIZE(ex) || N_DRSIZE(ex) || + i_size_read(file_inode(bprm->file)) < + ex.a_text+ex.a_data+N_SYMSIZE(ex)+N_TXTOFF(ex)) { + return -ENOEXEC; + } + + fd_offset = N_TXTOFF(ex); + + /* 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 = rlimit(RLIMIT_DATA); + if (rlim >= RLIM_INFINITY) + rlim = ~0; + if (ex.a_data + ex.a_bss > rlim) + return -ENOMEM; + + /* Flush all traces of the currently running executable */ + retval = flush_old_exec(bprm); + if (retval) + return retval; + + /* OK, This is the point of no return */ + set_personality(PER_LINUX); + set_personality_ia32(false); + + setup_new_exec(bprm); + + regs->cs = __USER32_CS; + regs->r8 = regs->r9 = regs->r10 = regs->r11 = regs->r12 = + regs->r13 = regs->r14 = regs->r15 = 0; + + 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)); + + retval = setup_arg_pages(bprm, IA32_STACK_TOP, EXSTACK_DEFAULT); + if (retval < 0) + return retval; + + install_exec_creds(bprm); + + if (N_MAGIC(ex) == OMAGIC) { + unsigned long text_addr, map_size; + + text_addr = N_TXTADDR(ex); + map_size = ex.a_text+ex.a_data; + + error = vm_brk(text_addr & PAGE_MASK, map_size); + + if (error != (text_addr & PAGE_MASK)) + return error; + + error = read_code(bprm->file, text_addr, 32, + ex.a_text + ex.a_data); + if ((signed long)error < 0) + return error; + } else { +#ifdef WARN_OLD + static unsigned long error_time, error_time2; + if ((ex.a_text & 0xfff || ex.a_data & 0xfff) && + (N_MAGIC(ex) != NMAGIC) && + time_after(jiffies, error_time2 + 5*HZ)) { + printk(KERN_NOTICE "executable not page aligned\n"); + error_time2 = jiffies; + } + + if ((fd_offset & ~PAGE_MASK) != 0 && + time_after(jiffies, error_time + 5*HZ)) { + printk(KERN_WARNING + "fd_offset is not page aligned. Please convert " + "program: %pD\n", + bprm->file); + error_time = jiffies; + } +#endif + + if (!bprm->file->f_op->mmap || (fd_offset & ~PAGE_MASK) != 0) { + vm_brk(N_TXTADDR(ex), ex.a_text+ex.a_data); + read_code(bprm->file, N_TXTADDR(ex), fd_offset, + ex.a_text+ex.a_data); + goto beyond_if; + } + + error = vm_mmap(bprm->file, N_TXTADDR(ex), ex.a_text, + PROT_READ | PROT_EXEC, + MAP_FIXED | MAP_PRIVATE | MAP_DENYWRITE | + MAP_EXECUTABLE | MAP_32BIT, + fd_offset); + + if (error != N_TXTADDR(ex)) + return error; + + error = vm_mmap(bprm->file, N_DATADDR(ex), ex.a_data, + PROT_READ | PROT_WRITE | PROT_EXEC, + MAP_FIXED | MAP_PRIVATE | MAP_DENYWRITE | + MAP_EXECUTABLE | MAP_32BIT, + fd_offset + ex.a_text); + if (error != N_DATADDR(ex)) + return error; + } +beyond_if: + set_binfmt(&aout_format); + + set_brk(current->mm->start_brk, current->mm->brk); + + current->mm->start_stack = + (unsigned long)create_aout_tables((char __user *)bprm->p, bprm); + /* start thread */ + loadsegment(fs, 0); + loadsegment(ds, __USER32_DS); + loadsegment(es, __USER32_DS); + load_gs_index(0); + (regs)->ip = ex.a_entry; + (regs)->sp = current->mm->start_stack; + (regs)->flags = 0x200; + (regs)->cs = __USER32_CS; + (regs)->ss = __USER32_DS; + regs->r8 = regs->r9 = regs->r10 = regs->r11 = + regs->r12 = regs->r13 = regs->r14 = regs->r15 = 0; + set_fs(USER_DS); + return 0; +} + +static int load_aout_library(struct file *file) +{ + unsigned long bss, start_addr, len, error; + int retval; + struct exec ex; + + + retval = -ENOEXEC; + error = kernel_read(file, 0, (char *) &ex, sizeof(ex)); + if (error != sizeof(ex)) + goto out; + + /* 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) || + i_size_read(file_inode(file)) < + ex.a_text+ex.a_data+N_SYMSIZE(ex)+N_TXTOFF(ex)) { + goto out; + } + + if (N_FLAGS(ex)) + goto out; + + /* 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; + + if ((N_TXTOFF(ex) & ~PAGE_MASK) != 0) { +#ifdef WARN_OLD + static unsigned long error_time; + if (time_after(jiffies, error_time + 5*HZ)) { + printk(KERN_WARNING + "N_TXTOFF is not page aligned. Please convert " + "library: %pD\n", + file); + error_time = jiffies; + } +#endif + vm_brk(start_addr, ex.a_text + ex.a_data + ex.a_bss); + + read_code(file, start_addr, N_TXTOFF(ex), + ex.a_text + ex.a_data); + retval = 0; + goto out; + } + /* Now use mmap to map the library into memory. */ + error = vm_mmap(file, start_addr, ex.a_text + ex.a_data, + PROT_READ | PROT_WRITE | PROT_EXEC, + MAP_FIXED | MAP_PRIVATE | MAP_DENYWRITE | MAP_32BIT, + N_TXTOFF(ex)); + retval = error; + if (error != start_addr) + goto out; + + len = PAGE_ALIGN(ex.a_text + ex.a_data); + bss = ex.a_text + ex.a_data + ex.a_bss; + if (bss > len) { + error = vm_brk(start_addr + len, bss - len); + retval = error; + if (error != start_addr + len) + goto out; + } + retval = 0; +out: + return retval; +} + +static int __init init_aout_binfmt(void) +{ + register_binfmt(&aout_format); + return 0; +} + +static void __exit exit_aout_binfmt(void) +{ + unregister_binfmt(&aout_format); +} + +module_init(init_aout_binfmt); +module_exit(exit_aout_binfmt); +MODULE_LICENSE("GPL"); -- cgit v1.2.3-54-g00ecf