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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
commit76cb841cb886eef6b3bee341a2266c76578724ad (patch)
treef5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /fs/binfmt_elf_fdpic.c
parentInitial commit. (diff)
downloadlinux-c109f8d9e922037b3fa45f46d78384d49db8ad76.tar.xz
linux-c109f8d9e922037b3fa45f46d78384d49db8ad76.zip
Adding upstream version 4.19.249.upstream/4.19.249upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'fs/binfmt_elf_fdpic.c')
-rw-r--r--fs/binfmt_elf_fdpic.c1817
1 files changed, 1817 insertions, 0 deletions
diff --git a/fs/binfmt_elf_fdpic.c b/fs/binfmt_elf_fdpic.c
new file mode 100644
index 000000000..b53bb3729
--- /dev/null
+++ b/fs/binfmt_elf_fdpic.c
@@ -0,0 +1,1817 @@
+/* binfmt_elf_fdpic.c: FDPIC ELF binary format
+ *
+ * Copyright (C) 2003, 2004, 2006 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ * Derived from binfmt_elf.c
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/module.h>
+
+#include <linux/fs.h>
+#include <linux/stat.h>
+#include <linux/sched.h>
+#include <linux/sched/coredump.h>
+#include <linux/sched/task_stack.h>
+#include <linux/sched/cputime.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/fcntl.h>
+#include <linux/slab.h>
+#include <linux/pagemap.h>
+#include <linux/security.h>
+#include <linux/highmem.h>
+#include <linux/highuid.h>
+#include <linux/personality.h>
+#include <linux/ptrace.h>
+#include <linux/init.h>
+#include <linux/elf.h>
+#include <linux/elf-fdpic.h>
+#include <linux/elfcore.h>
+#include <linux/coredump.h>
+#include <linux/dax.h>
+
+#include <linux/uaccess.h>
+#include <asm/param.h>
+#include <asm/pgalloc.h>
+
+typedef char *elf_caddr_t;
+
+#if 0
+#define kdebug(fmt, ...) printk("FDPIC "fmt"\n" ,##__VA_ARGS__ )
+#else
+#define kdebug(fmt, ...) do {} while(0)
+#endif
+
+#if 0
+#define kdcore(fmt, ...) printk("FDPIC "fmt"\n" ,##__VA_ARGS__ )
+#else
+#define kdcore(fmt, ...) do {} while(0)
+#endif
+
+MODULE_LICENSE("GPL");
+
+static int load_elf_fdpic_binary(struct linux_binprm *);
+static int elf_fdpic_fetch_phdrs(struct elf_fdpic_params *, struct file *);
+static int elf_fdpic_map_file(struct elf_fdpic_params *, struct file *,
+ struct mm_struct *, const char *);
+
+static int create_elf_fdpic_tables(struct linux_binprm *, struct mm_struct *,
+ struct elf_fdpic_params *,
+ struct elf_fdpic_params *);
+
+#ifndef CONFIG_MMU
+static int elf_fdpic_map_file_constdisp_on_uclinux(struct elf_fdpic_params *,
+ struct file *,
+ struct mm_struct *);
+#endif
+
+static int elf_fdpic_map_file_by_direct_mmap(struct elf_fdpic_params *,
+ struct file *, struct mm_struct *);
+
+#ifdef CONFIG_ELF_CORE
+static int elf_fdpic_core_dump(struct coredump_params *cprm);
+#endif
+
+static struct linux_binfmt elf_fdpic_format = {
+ .module = THIS_MODULE,
+ .load_binary = load_elf_fdpic_binary,
+#ifdef CONFIG_ELF_CORE
+ .core_dump = elf_fdpic_core_dump,
+#endif
+ .min_coredump = ELF_EXEC_PAGESIZE,
+};
+
+static int __init init_elf_fdpic_binfmt(void)
+{
+ register_binfmt(&elf_fdpic_format);
+ return 0;
+}
+
+static void __exit exit_elf_fdpic_binfmt(void)
+{
+ unregister_binfmt(&elf_fdpic_format);
+}
+
+core_initcall(init_elf_fdpic_binfmt);
+module_exit(exit_elf_fdpic_binfmt);
+
+static int is_elf(struct elfhdr *hdr, struct file *file)
+{
+ if (memcmp(hdr->e_ident, ELFMAG, SELFMAG) != 0)
+ return 0;
+ if (hdr->e_type != ET_EXEC && hdr->e_type != ET_DYN)
+ return 0;
+ if (!elf_check_arch(hdr))
+ return 0;
+ if (!file->f_op->mmap)
+ return 0;
+ return 1;
+}
+
+#ifndef elf_check_fdpic
+#define elf_check_fdpic(x) 0
+#endif
+
+#ifndef elf_check_const_displacement
+#define elf_check_const_displacement(x) 0
+#endif
+
+static int is_constdisp(struct elfhdr *hdr)
+{
+ if (!elf_check_fdpic(hdr))
+ return 1;
+ if (elf_check_const_displacement(hdr))
+ return 1;
+ return 0;
+}
+
+/*****************************************************************************/
+/*
+ * read the program headers table into memory
+ */
+static int elf_fdpic_fetch_phdrs(struct elf_fdpic_params *params,
+ struct file *file)
+{
+ struct elf32_phdr *phdr;
+ unsigned long size;
+ int retval, loop;
+ loff_t pos = params->hdr.e_phoff;
+
+ if (params->hdr.e_phentsize != sizeof(struct elf_phdr))
+ return -ENOMEM;
+ if (params->hdr.e_phnum > 65536U / sizeof(struct elf_phdr))
+ return -ENOMEM;
+
+ size = params->hdr.e_phnum * sizeof(struct elf_phdr);
+ params->phdrs = kmalloc(size, GFP_KERNEL);
+ if (!params->phdrs)
+ return -ENOMEM;
+
+ retval = kernel_read(file, params->phdrs, size, &pos);
+ if (unlikely(retval != size))
+ return retval < 0 ? retval : -ENOEXEC;
+
+ /* determine stack size for this binary */
+ phdr = params->phdrs;
+ for (loop = 0; loop < params->hdr.e_phnum; loop++, phdr++) {
+ if (phdr->p_type != PT_GNU_STACK)
+ continue;
+
+ if (phdr->p_flags & PF_X)
+ params->flags |= ELF_FDPIC_FLAG_EXEC_STACK;
+ else
+ params->flags |= ELF_FDPIC_FLAG_NOEXEC_STACK;
+
+ params->stack_size = phdr->p_memsz;
+ break;
+ }
+
+ return 0;
+}
+
+/*****************************************************************************/
+/*
+ * load an fdpic binary into various bits of memory
+ */
+static int load_elf_fdpic_binary(struct linux_binprm *bprm)
+{
+ struct elf_fdpic_params exec_params, interp_params;
+ struct pt_regs *regs = current_pt_regs();
+ struct elf_phdr *phdr;
+ unsigned long stack_size, entryaddr;
+#ifdef ELF_FDPIC_PLAT_INIT
+ unsigned long dynaddr;
+#endif
+#ifndef CONFIG_MMU
+ unsigned long stack_prot;
+#endif
+ struct file *interpreter = NULL; /* to shut gcc up */
+ char *interpreter_name = NULL;
+ int executable_stack;
+ int retval, i;
+ loff_t pos;
+
+ kdebug("____ LOAD %d ____", current->pid);
+
+ memset(&exec_params, 0, sizeof(exec_params));
+ memset(&interp_params, 0, sizeof(interp_params));
+
+ exec_params.hdr = *(struct elfhdr *) bprm->buf;
+ exec_params.flags = ELF_FDPIC_FLAG_PRESENT | ELF_FDPIC_FLAG_EXECUTABLE;
+
+ /* check that this is a binary we know how to deal with */
+ retval = -ENOEXEC;
+ if (!is_elf(&exec_params.hdr, bprm->file))
+ goto error;
+ if (!elf_check_fdpic(&exec_params.hdr)) {
+#ifdef CONFIG_MMU
+ /* binfmt_elf handles non-fdpic elf except on nommu */
+ goto error;
+#else
+ /* nommu can only load ET_DYN (PIE) ELF */
+ if (exec_params.hdr.e_type != ET_DYN)
+ goto error;
+#endif
+ }
+
+ /* read the program header table */
+ retval = elf_fdpic_fetch_phdrs(&exec_params, bprm->file);
+ if (retval < 0)
+ goto error;
+
+ /* scan for a program header that specifies an interpreter */
+ phdr = exec_params.phdrs;
+
+ for (i = 0; i < exec_params.hdr.e_phnum; i++, phdr++) {
+ switch (phdr->p_type) {
+ case PT_INTERP:
+ retval = -ENOMEM;
+ if (phdr->p_filesz > PATH_MAX)
+ goto error;
+ retval = -ENOENT;
+ if (phdr->p_filesz < 2)
+ goto error;
+
+ /* read the name of the interpreter into memory */
+ interpreter_name = kmalloc(phdr->p_filesz, GFP_KERNEL);
+ if (!interpreter_name)
+ goto error;
+
+ pos = phdr->p_offset;
+ retval = kernel_read(bprm->file, interpreter_name,
+ phdr->p_filesz, &pos);
+ if (unlikely(retval != phdr->p_filesz)) {
+ if (retval >= 0)
+ retval = -ENOEXEC;
+ goto error;
+ }
+
+ retval = -ENOENT;
+ if (interpreter_name[phdr->p_filesz - 1] != '\0')
+ goto error;
+
+ kdebug("Using ELF interpreter %s", interpreter_name);
+
+ /* replace the program with the interpreter */
+ interpreter = open_exec(interpreter_name);
+ retval = PTR_ERR(interpreter);
+ if (IS_ERR(interpreter)) {
+ interpreter = NULL;
+ goto error;
+ }
+
+ /*
+ * If the binary is not readable then enforce
+ * mm->dumpable = 0 regardless of the interpreter's
+ * permissions.
+ */
+ would_dump(bprm, interpreter);
+
+ pos = 0;
+ retval = kernel_read(interpreter, bprm->buf,
+ BINPRM_BUF_SIZE, &pos);
+ if (unlikely(retval != BINPRM_BUF_SIZE)) {
+ if (retval >= 0)
+ retval = -ENOEXEC;
+ goto error;
+ }
+
+ interp_params.hdr = *((struct elfhdr *) bprm->buf);
+ break;
+
+ case PT_LOAD:
+#ifdef CONFIG_MMU
+ if (exec_params.load_addr == 0)
+ exec_params.load_addr = phdr->p_vaddr;
+#endif
+ break;
+ }
+
+ }
+
+ if (is_constdisp(&exec_params.hdr))
+ exec_params.flags |= ELF_FDPIC_FLAG_CONSTDISP;
+
+ /* perform insanity checks on the interpreter */
+ if (interpreter_name) {
+ retval = -ELIBBAD;
+ if (!is_elf(&interp_params.hdr, interpreter))
+ goto error;
+
+ interp_params.flags = ELF_FDPIC_FLAG_PRESENT;
+
+ /* read the interpreter's program header table */
+ retval = elf_fdpic_fetch_phdrs(&interp_params, interpreter);
+ if (retval < 0)
+ goto error;
+ }
+
+ stack_size = exec_params.stack_size;
+ if (exec_params.flags & ELF_FDPIC_FLAG_EXEC_STACK)
+ executable_stack = EXSTACK_ENABLE_X;
+ else if (exec_params.flags & ELF_FDPIC_FLAG_NOEXEC_STACK)
+ executable_stack = EXSTACK_DISABLE_X;
+ else
+ executable_stack = EXSTACK_DEFAULT;
+
+ if (stack_size == 0) {
+ stack_size = interp_params.stack_size;
+ if (interp_params.flags & ELF_FDPIC_FLAG_EXEC_STACK)
+ executable_stack = EXSTACK_ENABLE_X;
+ else if (interp_params.flags & ELF_FDPIC_FLAG_NOEXEC_STACK)
+ executable_stack = EXSTACK_DISABLE_X;
+ else
+ executable_stack = EXSTACK_DEFAULT;
+ }
+
+ retval = -ENOEXEC;
+ if (stack_size == 0)
+ stack_size = 131072UL; /* same as exec.c's default commit */
+
+ if (is_constdisp(&interp_params.hdr))
+ interp_params.flags |= ELF_FDPIC_FLAG_CONSTDISP;
+
+ /* flush all traces of the currently running executable */
+ retval = flush_old_exec(bprm);
+ if (retval)
+ goto error;
+
+ /* there's now no turning back... the old userspace image is dead,
+ * defunct, deceased, etc.
+ */
+ if (elf_check_fdpic(&exec_params.hdr))
+ set_personality(PER_LINUX_FDPIC);
+ else
+ set_personality(PER_LINUX);
+ if (elf_read_implies_exec(&exec_params.hdr, executable_stack))
+ current->personality |= READ_IMPLIES_EXEC;
+
+ setup_new_exec(bprm);
+
+ set_binfmt(&elf_fdpic_format);
+
+ current->mm->start_code = 0;
+ current->mm->end_code = 0;
+ current->mm->start_stack = 0;
+ current->mm->start_data = 0;
+ current->mm->end_data = 0;
+ current->mm->context.exec_fdpic_loadmap = 0;
+ current->mm->context.interp_fdpic_loadmap = 0;
+
+#ifdef CONFIG_MMU
+ elf_fdpic_arch_lay_out_mm(&exec_params,
+ &interp_params,
+ &current->mm->start_stack,
+ &current->mm->start_brk);
+
+ retval = setup_arg_pages(bprm, current->mm->start_stack,
+ executable_stack);
+ if (retval < 0)
+ goto error;
+#ifdef ARCH_HAS_SETUP_ADDITIONAL_PAGES
+ retval = arch_setup_additional_pages(bprm, !!interpreter_name);
+ if (retval < 0)
+ goto error;
+#endif
+#endif
+
+ /* load the executable and interpreter into memory */
+ retval = elf_fdpic_map_file(&exec_params, bprm->file, current->mm,
+ "executable");
+ if (retval < 0)
+ goto error;
+
+ if (interpreter_name) {
+ retval = elf_fdpic_map_file(&interp_params, interpreter,
+ current->mm, "interpreter");
+ if (retval < 0) {
+ printk(KERN_ERR "Unable to load interpreter\n");
+ goto error;
+ }
+
+ allow_write_access(interpreter);
+ fput(interpreter);
+ interpreter = NULL;
+ }
+
+#ifdef CONFIG_MMU
+ if (!current->mm->start_brk)
+ current->mm->start_brk = current->mm->end_data;
+
+ current->mm->brk = current->mm->start_brk =
+ PAGE_ALIGN(current->mm->start_brk);
+
+#else
+ /* create a stack area and zero-size brk area */
+ stack_size = (stack_size + PAGE_SIZE - 1) & PAGE_MASK;
+ if (stack_size < PAGE_SIZE * 2)
+ stack_size = PAGE_SIZE * 2;
+
+ stack_prot = PROT_READ | PROT_WRITE;
+ if (executable_stack == EXSTACK_ENABLE_X ||
+ (executable_stack == EXSTACK_DEFAULT && VM_STACK_FLAGS & VM_EXEC))
+ stack_prot |= PROT_EXEC;
+
+ current->mm->start_brk = vm_mmap(NULL, 0, stack_size, stack_prot,
+ MAP_PRIVATE | MAP_ANONYMOUS |
+ MAP_UNINITIALIZED | MAP_GROWSDOWN,
+ 0);
+
+ if (IS_ERR_VALUE(current->mm->start_brk)) {
+ retval = current->mm->start_brk;
+ current->mm->start_brk = 0;
+ goto error;
+ }
+
+ current->mm->brk = current->mm->start_brk;
+ current->mm->context.end_brk = current->mm->start_brk;
+ current->mm->start_stack = current->mm->start_brk + stack_size;
+#endif
+
+ install_exec_creds(bprm);
+ if (create_elf_fdpic_tables(bprm, current->mm,
+ &exec_params, &interp_params) < 0)
+ goto error;
+
+ kdebug("- start_code %lx", current->mm->start_code);
+ kdebug("- end_code %lx", current->mm->end_code);
+ kdebug("- start_data %lx", current->mm->start_data);
+ kdebug("- end_data %lx", current->mm->end_data);
+ kdebug("- start_brk %lx", current->mm->start_brk);
+ kdebug("- brk %lx", current->mm->brk);
+ kdebug("- start_stack %lx", current->mm->start_stack);
+
+#ifdef ELF_FDPIC_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. This macro performs whatever initialization to
+ * the regs structure is required.
+ */
+ dynaddr = interp_params.dynamic_addr ?: exec_params.dynamic_addr;
+ ELF_FDPIC_PLAT_INIT(regs, exec_params.map_addr, interp_params.map_addr,
+ dynaddr);
+#endif
+
+ finalize_exec(bprm);
+ /* everything is now ready... get the userspace context ready to roll */
+ entryaddr = interp_params.entry_addr ?: exec_params.entry_addr;
+ start_thread(regs, entryaddr, current->mm->start_stack);
+
+ retval = 0;
+
+error:
+ if (interpreter) {
+ allow_write_access(interpreter);
+ fput(interpreter);
+ }
+ kfree(interpreter_name);
+ kfree(exec_params.phdrs);
+ kfree(exec_params.loadmap);
+ kfree(interp_params.phdrs);
+ kfree(interp_params.loadmap);
+ return retval;
+}
+
+/*****************************************************************************/
+
+#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
+
+/*
+ * present useful information to the program by shovelling it onto the new
+ * process's stack
+ */
+static int create_elf_fdpic_tables(struct linux_binprm *bprm,
+ struct mm_struct *mm,
+ struct elf_fdpic_params *exec_params,
+ struct elf_fdpic_params *interp_params)
+{
+ const struct cred *cred = current_cred();
+ unsigned long sp, csp, nitems;
+ elf_caddr_t __user *argv, *envp;
+ size_t platform_len = 0, len;
+ char *k_platform, *k_base_platform;
+ char __user *u_platform, *u_base_platform, *p;
+ int loop;
+ int nr; /* reset for each csp adjustment */
+
+#ifdef CONFIG_MMU
+ /* 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, so we give the architecture
+ * an opportunity to do so here.
+ */
+ sp = arch_align_stack(bprm->p);
+#else
+ sp = mm->start_stack;
+
+ /* stack the program arguments and environment */
+ if (transfer_args_to_stack(bprm, &sp) < 0)
+ return -EFAULT;
+ sp &= ~15;
+#endif
+
+ /*
+ * 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.
+ */
+ k_platform = ELF_PLATFORM;
+ u_platform = NULL;
+
+ if (k_platform) {
+ platform_len = strlen(k_platform) + 1;
+ sp -= platform_len;
+ u_platform = (char __user *) sp;
+ if (__copy_to_user(u_platform, k_platform, platform_len) != 0)
+ return -EFAULT;
+ }
+
+ /*
+ * If this architecture has a "base" platform capability
+ * string, copy it to userspace.
+ */
+ k_base_platform = ELF_BASE_PLATFORM;
+ u_base_platform = NULL;
+
+ if (k_base_platform) {
+ platform_len = strlen(k_base_platform) + 1;
+ sp -= platform_len;
+ u_base_platform = (char __user *) sp;
+ if (__copy_to_user(u_base_platform, k_base_platform, platform_len) != 0)
+ return -EFAULT;
+ }
+
+ sp &= ~7UL;
+
+ /* stack the load map(s) */
+ len = sizeof(struct elf32_fdpic_loadmap);
+ len += sizeof(struct elf32_fdpic_loadseg) * exec_params->loadmap->nsegs;
+ sp = (sp - len) & ~7UL;
+ exec_params->map_addr = sp;
+
+ if (copy_to_user((void __user *) sp, exec_params->loadmap, len) != 0)
+ return -EFAULT;
+
+ current->mm->context.exec_fdpic_loadmap = (unsigned long) sp;
+
+ if (interp_params->loadmap) {
+ len = sizeof(struct elf32_fdpic_loadmap);
+ len += sizeof(struct elf32_fdpic_loadseg) *
+ interp_params->loadmap->nsegs;
+ sp = (sp - len) & ~7UL;
+ interp_params->map_addr = sp;
+
+ if (copy_to_user((void __user *) sp, interp_params->loadmap,
+ len) != 0)
+ return -EFAULT;
+
+ current->mm->context.interp_fdpic_loadmap = (unsigned long) sp;
+ }
+
+ /* force 16 byte _final_ alignment here for generality */
+#define DLINFO_ITEMS 15
+
+ nitems = 1 + DLINFO_ITEMS + (k_platform ? 1 : 0) +
+ (k_base_platform ? 1 : 0) + AT_VECTOR_SIZE_ARCH;
+
+ if (bprm->interp_flags & BINPRM_FLAGS_EXECFD)
+ nitems++;
+
+ csp = sp;
+ sp -= nitems * 2 * sizeof(unsigned long);
+ sp -= (bprm->envc + 1) * sizeof(char *); /* envv[] */
+ sp -= (bprm->argc + 1) * sizeof(char *); /* argv[] */
+ sp -= 1 * sizeof(unsigned long); /* argc */
+
+ csp -= sp & 15UL;
+ sp -= sp & 15UL;
+
+ /* put the ELF interpreter info on the stack */
+#define NEW_AUX_ENT(id, val) \
+ do { \
+ struct { unsigned long _id, _val; } __user *ent; \
+ \
+ ent = (void __user *) csp; \
+ __put_user((id), &ent[nr]._id); \
+ __put_user((val), &ent[nr]._val); \
+ nr++; \
+ } while (0)
+
+ nr = 0;
+ csp -= 2 * sizeof(unsigned long);
+ NEW_AUX_ENT(AT_NULL, 0);
+ if (k_platform) {
+ nr = 0;
+ csp -= 2 * sizeof(unsigned long);
+ NEW_AUX_ENT(AT_PLATFORM,
+ (elf_addr_t) (unsigned long) u_platform);
+ }
+
+ if (k_base_platform) {
+ nr = 0;
+ csp -= 2 * sizeof(unsigned long);
+ NEW_AUX_ENT(AT_BASE_PLATFORM,
+ (elf_addr_t) (unsigned long) u_base_platform);
+ }
+
+ if (bprm->interp_flags & BINPRM_FLAGS_EXECFD) {
+ nr = 0;
+ csp -= 2 * sizeof(unsigned long);
+ NEW_AUX_ENT(AT_EXECFD, bprm->interp_data);
+ }
+
+ nr = 0;
+ csp -= DLINFO_ITEMS * 2 * sizeof(unsigned long);
+ NEW_AUX_ENT(AT_HWCAP, ELF_HWCAP);
+#ifdef ELF_HWCAP2
+ NEW_AUX_ENT(AT_HWCAP2, ELF_HWCAP2);
+#endif
+ NEW_AUX_ENT(AT_PAGESZ, PAGE_SIZE);
+ NEW_AUX_ENT(AT_CLKTCK, CLOCKS_PER_SEC);
+ NEW_AUX_ENT(AT_PHDR, exec_params->ph_addr);
+ NEW_AUX_ENT(AT_PHENT, sizeof(struct elf_phdr));
+ NEW_AUX_ENT(AT_PHNUM, exec_params->hdr.e_phnum);
+ NEW_AUX_ENT(AT_BASE, interp_params->elfhdr_addr);
+ NEW_AUX_ENT(AT_FLAGS, 0);
+ NEW_AUX_ENT(AT_ENTRY, exec_params->entry_addr);
+ NEW_AUX_ENT(AT_UID, (elf_addr_t) from_kuid_munged(cred->user_ns, cred->uid));
+ NEW_AUX_ENT(AT_EUID, (elf_addr_t) from_kuid_munged(cred->user_ns, cred->euid));
+ NEW_AUX_ENT(AT_GID, (elf_addr_t) from_kgid_munged(cred->user_ns, cred->gid));
+ NEW_AUX_ENT(AT_EGID, (elf_addr_t) from_kgid_munged(cred->user_ns, cred->egid));
+ NEW_AUX_ENT(AT_SECURE, bprm->secureexec);
+ NEW_AUX_ENT(AT_EXECFN, bprm->exec);
+
+#ifdef ARCH_DLINFO
+ nr = 0;
+ csp -= AT_VECTOR_SIZE_ARCH * 2 * sizeof(unsigned long);
+
+ /* ARCH_DLINFO must come last so platform specific code can enforce
+ * special alignment requirements on the AUXV if necessary (eg. PPC).
+ */
+ ARCH_DLINFO;
+#endif
+#undef NEW_AUX_ENT
+
+ /* allocate room for argv[] and envv[] */
+ csp -= (bprm->envc + 1) * sizeof(elf_caddr_t);
+ envp = (elf_caddr_t __user *) csp;
+ csp -= (bprm->argc + 1) * sizeof(elf_caddr_t);
+ argv = (elf_caddr_t __user *) csp;
+
+ /* stack argc */
+ csp -= sizeof(unsigned long);
+ __put_user(bprm->argc, (unsigned long __user *) csp);
+
+ BUG_ON(csp != sp);
+
+ /* fill in the argv[] array */
+#ifdef CONFIG_MMU
+ current->mm->arg_start = bprm->p;
+#else
+ current->mm->arg_start = current->mm->start_stack -
+ (MAX_ARG_PAGES * PAGE_SIZE - bprm->p);
+#endif
+
+ p = (char __user *) current->mm->arg_start;
+ for (loop = bprm->argc; loop > 0; loop--) {
+ __put_user((elf_caddr_t) p, argv++);
+ len = strnlen_user(p, MAX_ARG_STRLEN);
+ if (!len || len > MAX_ARG_STRLEN)
+ return -EINVAL;
+ p += len;
+ }
+ __put_user(NULL, argv);
+ current->mm->arg_end = (unsigned long) p;
+
+ /* fill in the envv[] array */
+ current->mm->env_start = (unsigned long) p;
+ for (loop = bprm->envc; loop > 0; loop--) {
+ __put_user((elf_caddr_t)(unsigned long) p, envp++);
+ len = strnlen_user(p, MAX_ARG_STRLEN);
+ if (!len || len > MAX_ARG_STRLEN)
+ return -EINVAL;
+ p += len;
+ }
+ __put_user(NULL, envp);
+ current->mm->env_end = (unsigned long) p;
+
+ mm->start_stack = (unsigned long) sp;
+ return 0;
+}
+
+/*****************************************************************************/
+/*
+ * load the appropriate binary image (executable or interpreter) into memory
+ * - we assume no MMU is available
+ * - if no other PIC bits are set in params->hdr->e_flags
+ * - we assume that the LOADable segments in the binary are independently relocatable
+ * - we assume R/O executable segments are shareable
+ * - else
+ * - we assume the loadable parts of the image to require fixed displacement
+ * - the image is not shareable
+ */
+static int elf_fdpic_map_file(struct elf_fdpic_params *params,
+ struct file *file,
+ struct mm_struct *mm,
+ const char *what)
+{
+ struct elf32_fdpic_loadmap *loadmap;
+#ifdef CONFIG_MMU
+ struct elf32_fdpic_loadseg *mseg;
+#endif
+ struct elf32_fdpic_loadseg *seg;
+ struct elf32_phdr *phdr;
+ unsigned long load_addr, stop;
+ unsigned nloads, tmp;
+ size_t size;
+ int loop, ret;
+
+ /* allocate a load map table */
+ nloads = 0;
+ for (loop = 0; loop < params->hdr.e_phnum; loop++)
+ if (params->phdrs[loop].p_type == PT_LOAD)
+ nloads++;
+
+ if (nloads == 0)
+ return -ELIBBAD;
+
+ size = sizeof(*loadmap) + nloads * sizeof(*seg);
+ loadmap = kzalloc(size, GFP_KERNEL);
+ if (!loadmap)
+ return -ENOMEM;
+
+ params->loadmap = loadmap;
+
+ loadmap->version = ELF32_FDPIC_LOADMAP_VERSION;
+ loadmap->nsegs = nloads;
+
+ load_addr = params->load_addr;
+ seg = loadmap->segs;
+
+ /* map the requested LOADs into the memory space */
+ switch (params->flags & ELF_FDPIC_FLAG_ARRANGEMENT) {
+ case ELF_FDPIC_FLAG_CONSTDISP:
+ case ELF_FDPIC_FLAG_CONTIGUOUS:
+#ifndef CONFIG_MMU
+ ret = elf_fdpic_map_file_constdisp_on_uclinux(params, file, mm);
+ if (ret < 0)
+ return ret;
+ break;
+#endif
+ default:
+ ret = elf_fdpic_map_file_by_direct_mmap(params, file, mm);
+ if (ret < 0)
+ return ret;
+ break;
+ }
+
+ /* map the entry point */
+ if (params->hdr.e_entry) {
+ seg = loadmap->segs;
+ for (loop = loadmap->nsegs; loop > 0; loop--, seg++) {
+ if (params->hdr.e_entry >= seg->p_vaddr &&
+ params->hdr.e_entry < seg->p_vaddr + seg->p_memsz) {
+ params->entry_addr =
+ (params->hdr.e_entry - seg->p_vaddr) +
+ seg->addr;
+ break;
+ }
+ }
+ }
+
+ /* determine where the program header table has wound up if mapped */
+ stop = params->hdr.e_phoff;
+ stop += params->hdr.e_phnum * sizeof (struct elf_phdr);
+ phdr = params->phdrs;
+
+ for (loop = 0; loop < params->hdr.e_phnum; loop++, phdr++) {
+ if (phdr->p_type != PT_LOAD)
+ continue;
+
+ if (phdr->p_offset > params->hdr.e_phoff ||
+ phdr->p_offset + phdr->p_filesz < stop)
+ continue;
+
+ seg = loadmap->segs;
+ for (loop = loadmap->nsegs; loop > 0; loop--, seg++) {
+ if (phdr->p_vaddr >= seg->p_vaddr &&
+ phdr->p_vaddr + phdr->p_filesz <=
+ seg->p_vaddr + seg->p_memsz) {
+ params->ph_addr =
+ (phdr->p_vaddr - seg->p_vaddr) +
+ seg->addr +
+ params->hdr.e_phoff - phdr->p_offset;
+ break;
+ }
+ }
+ break;
+ }
+
+ /* determine where the dynamic section has wound up if there is one */
+ phdr = params->phdrs;
+ for (loop = 0; loop < params->hdr.e_phnum; loop++, phdr++) {
+ if (phdr->p_type != PT_DYNAMIC)
+ continue;
+
+ seg = loadmap->segs;
+ for (loop = loadmap->nsegs; loop > 0; loop--, seg++) {
+ if (phdr->p_vaddr >= seg->p_vaddr &&
+ phdr->p_vaddr + phdr->p_memsz <=
+ seg->p_vaddr + seg->p_memsz) {
+ Elf32_Dyn __user *dyn;
+ Elf32_Sword d_tag;
+
+ params->dynamic_addr =
+ (phdr->p_vaddr - seg->p_vaddr) +
+ seg->addr;
+
+ /* check the dynamic section contains at least
+ * one item, and that the last item is a NULL
+ * entry */
+ if (phdr->p_memsz == 0 ||
+ phdr->p_memsz % sizeof(Elf32_Dyn) != 0)
+ goto dynamic_error;
+
+ tmp = phdr->p_memsz / sizeof(Elf32_Dyn);
+ dyn = (Elf32_Dyn __user *)params->dynamic_addr;
+ __get_user(d_tag, &dyn[tmp - 1].d_tag);
+ if (d_tag != 0)
+ goto dynamic_error;
+ break;
+ }
+ }
+ break;
+ }
+
+ /* now elide adjacent segments in the load map on MMU linux
+ * - on uClinux the holes between may actually be filled with system
+ * stuff or stuff from other processes
+ */
+#ifdef CONFIG_MMU
+ nloads = loadmap->nsegs;
+ mseg = loadmap->segs;
+ seg = mseg + 1;
+ for (loop = 1; loop < nloads; loop++) {
+ /* see if we have a candidate for merging */
+ if (seg->p_vaddr - mseg->p_vaddr == seg->addr - mseg->addr) {
+ load_addr = PAGE_ALIGN(mseg->addr + mseg->p_memsz);
+ if (load_addr == (seg->addr & PAGE_MASK)) {
+ mseg->p_memsz +=
+ load_addr -
+ (mseg->addr + mseg->p_memsz);
+ mseg->p_memsz += seg->addr & ~PAGE_MASK;
+ mseg->p_memsz += seg->p_memsz;
+ loadmap->nsegs--;
+ continue;
+ }
+ }
+
+ mseg++;
+ if (mseg != seg)
+ *mseg = *seg;
+ }
+#endif
+
+ kdebug("Mapped Object [%s]:", what);
+ kdebug("- elfhdr : %lx", params->elfhdr_addr);
+ kdebug("- entry : %lx", params->entry_addr);
+ kdebug("- PHDR[] : %lx", params->ph_addr);
+ kdebug("- DYNAMIC[]: %lx", params->dynamic_addr);
+ seg = loadmap->segs;
+ for (loop = 0; loop < loadmap->nsegs; loop++, seg++)
+ kdebug("- LOAD[%d] : %08x-%08x [va=%x ms=%x]",
+ loop,
+ seg->addr, seg->addr + seg->p_memsz - 1,
+ seg->p_vaddr, seg->p_memsz);
+
+ return 0;
+
+dynamic_error:
+ printk("ELF FDPIC %s with invalid DYNAMIC section (inode=%lu)\n",
+ what, file_inode(file)->i_ino);
+ return -ELIBBAD;
+}
+
+/*****************************************************************************/
+/*
+ * map a file with constant displacement under uClinux
+ */
+#ifndef CONFIG_MMU
+static int elf_fdpic_map_file_constdisp_on_uclinux(
+ struct elf_fdpic_params *params,
+ struct file *file,
+ struct mm_struct *mm)
+{
+ struct elf32_fdpic_loadseg *seg;
+ struct elf32_phdr *phdr;
+ unsigned long load_addr, base = ULONG_MAX, top = 0, maddr = 0, mflags;
+ int loop, ret;
+
+ load_addr = params->load_addr;
+ seg = params->loadmap->segs;
+
+ /* determine the bounds of the contiguous overall allocation we must
+ * make */
+ phdr = params->phdrs;
+ for (loop = 0; loop < params->hdr.e_phnum; loop++, phdr++) {
+ if (params->phdrs[loop].p_type != PT_LOAD)
+ continue;
+
+ if (base > phdr->p_vaddr)
+ base = phdr->p_vaddr;
+ if (top < phdr->p_vaddr + phdr->p_memsz)
+ top = phdr->p_vaddr + phdr->p_memsz;
+ }
+
+ /* allocate one big anon block for everything */
+ mflags = MAP_PRIVATE;
+ if (params->flags & ELF_FDPIC_FLAG_EXECUTABLE)
+ mflags |= MAP_EXECUTABLE;
+
+ maddr = vm_mmap(NULL, load_addr, top - base,
+ PROT_READ | PROT_WRITE | PROT_EXEC, mflags, 0);
+ if (IS_ERR_VALUE(maddr))
+ return (int) maddr;
+
+ if (load_addr != 0)
+ load_addr += PAGE_ALIGN(top - base);
+
+ /* and then load the file segments into it */
+ phdr = params->phdrs;
+ for (loop = 0; loop < params->hdr.e_phnum; loop++, phdr++) {
+ if (params->phdrs[loop].p_type != PT_LOAD)
+ continue;
+
+ seg->addr = maddr + (phdr->p_vaddr - base);
+ seg->p_vaddr = phdr->p_vaddr;
+ seg->p_memsz = phdr->p_memsz;
+
+ ret = read_code(file, seg->addr, phdr->p_offset,
+ phdr->p_filesz);
+ if (ret < 0)
+ return ret;
+
+ /* map the ELF header address if in this segment */
+ if (phdr->p_offset == 0)
+ params->elfhdr_addr = seg->addr;
+
+ /* clear any space allocated but not loaded */
+ if (phdr->p_filesz < phdr->p_memsz) {
+ if (clear_user((void *) (seg->addr + phdr->p_filesz),
+ phdr->p_memsz - phdr->p_filesz))
+ return -EFAULT;
+ }
+
+ if (mm) {
+ if (phdr->p_flags & PF_X) {
+ if (!mm->start_code) {
+ mm->start_code = seg->addr;
+ mm->end_code = seg->addr +
+ phdr->p_memsz;
+ }
+ } else if (!mm->start_data) {
+ mm->start_data = seg->addr;
+ mm->end_data = seg->addr + phdr->p_memsz;
+ }
+ }
+
+ seg++;
+ }
+
+ return 0;
+}
+#endif
+
+/*****************************************************************************/
+/*
+ * map a binary by direct mmap() of the individual PT_LOAD segments
+ */
+static int elf_fdpic_map_file_by_direct_mmap(struct elf_fdpic_params *params,
+ struct file *file,
+ struct mm_struct *mm)
+{
+ struct elf32_fdpic_loadseg *seg;
+ struct elf32_phdr *phdr;
+ unsigned long load_addr, delta_vaddr;
+ int loop, dvset;
+
+ load_addr = params->load_addr;
+ delta_vaddr = 0;
+ dvset = 0;
+
+ seg = params->loadmap->segs;
+
+ /* deal with each load segment separately */
+ phdr = params->phdrs;
+ for (loop = 0; loop < params->hdr.e_phnum; loop++, phdr++) {
+ unsigned long maddr, disp, excess, excess1;
+ int prot = 0, flags;
+
+ if (phdr->p_type != PT_LOAD)
+ continue;
+
+ kdebug("[LOAD] va=%lx of=%lx fs=%lx ms=%lx",
+ (unsigned long) phdr->p_vaddr,
+ (unsigned long) phdr->p_offset,
+ (unsigned long) phdr->p_filesz,
+ (unsigned long) phdr->p_memsz);
+
+ /* determine the mapping parameters */
+ if (phdr->p_flags & PF_R) prot |= PROT_READ;
+ if (phdr->p_flags & PF_W) prot |= PROT_WRITE;
+ if (phdr->p_flags & PF_X) prot |= PROT_EXEC;
+
+ flags = MAP_PRIVATE | MAP_DENYWRITE;
+ if (params->flags & ELF_FDPIC_FLAG_EXECUTABLE)
+ flags |= MAP_EXECUTABLE;
+
+ maddr = 0;
+
+ switch (params->flags & ELF_FDPIC_FLAG_ARRANGEMENT) {
+ case ELF_FDPIC_FLAG_INDEPENDENT:
+ /* PT_LOADs are independently locatable */
+ break;
+
+ case ELF_FDPIC_FLAG_HONOURVADDR:
+ /* the specified virtual address must be honoured */
+ maddr = phdr->p_vaddr;
+ flags |= MAP_FIXED;
+ break;
+
+ case ELF_FDPIC_FLAG_CONSTDISP:
+ /* constant displacement
+ * - can be mapped anywhere, but must be mapped as a
+ * unit
+ */
+ if (!dvset) {
+ maddr = load_addr;
+ delta_vaddr = phdr->p_vaddr;
+ dvset = 1;
+ } else {
+ maddr = load_addr + phdr->p_vaddr - delta_vaddr;
+ flags |= MAP_FIXED;
+ }
+ break;
+
+ case ELF_FDPIC_FLAG_CONTIGUOUS:
+ /* contiguity handled later */
+ break;
+
+ default:
+ BUG();
+ }
+
+ maddr &= PAGE_MASK;
+
+ /* create the mapping */
+ disp = phdr->p_vaddr & ~PAGE_MASK;
+ maddr = vm_mmap(file, maddr, phdr->p_memsz + disp, prot, flags,
+ phdr->p_offset - disp);
+
+ kdebug("mmap[%d] <file> sz=%lx pr=%x fl=%x of=%lx --> %08lx",
+ loop, phdr->p_memsz + disp, prot, flags,
+ phdr->p_offset - disp, maddr);
+
+ if (IS_ERR_VALUE(maddr))
+ return (int) maddr;
+
+ if ((params->flags & ELF_FDPIC_FLAG_ARRANGEMENT) ==
+ ELF_FDPIC_FLAG_CONTIGUOUS)
+ load_addr += PAGE_ALIGN(phdr->p_memsz + disp);
+
+ seg->addr = maddr + disp;
+ seg->p_vaddr = phdr->p_vaddr;
+ seg->p_memsz = phdr->p_memsz;
+
+ /* map the ELF header address if in this segment */
+ if (phdr->p_offset == 0)
+ params->elfhdr_addr = seg->addr;
+
+ /* clear the bit between beginning of mapping and beginning of
+ * PT_LOAD */
+ if (prot & PROT_WRITE && disp > 0) {
+ kdebug("clear[%d] ad=%lx sz=%lx", loop, maddr, disp);
+ if (clear_user((void __user *) maddr, disp))
+ return -EFAULT;
+ maddr += disp;
+ }
+
+ /* clear any space allocated but not loaded
+ * - on uClinux we can just clear the lot
+ * - on MMU linux we'll get a SIGBUS beyond the last page
+ * extant in the file
+ */
+ excess = phdr->p_memsz - phdr->p_filesz;
+ excess1 = PAGE_SIZE - ((maddr + phdr->p_filesz) & ~PAGE_MASK);
+
+#ifdef CONFIG_MMU
+ if (excess > excess1) {
+ unsigned long xaddr = maddr + phdr->p_filesz + excess1;
+ unsigned long xmaddr;
+
+ flags |= MAP_FIXED | MAP_ANONYMOUS;
+ xmaddr = vm_mmap(NULL, xaddr, excess - excess1,
+ prot, flags, 0);
+
+ kdebug("mmap[%d] <anon>"
+ " ad=%lx sz=%lx pr=%x fl=%x of=0 --> %08lx",
+ loop, xaddr, excess - excess1, prot, flags,
+ xmaddr);
+
+ if (xmaddr != xaddr)
+ return -ENOMEM;
+ }
+
+ if (prot & PROT_WRITE && excess1 > 0) {
+ kdebug("clear[%d] ad=%lx sz=%lx",
+ loop, maddr + phdr->p_filesz, excess1);
+ if (clear_user((void __user *) maddr + phdr->p_filesz,
+ excess1))
+ return -EFAULT;
+ }
+
+#else
+ if (excess > 0) {
+ kdebug("clear[%d] ad=%lx sz=%lx",
+ loop, maddr + phdr->p_filesz, excess);
+ if (clear_user((void *) maddr + phdr->p_filesz, excess))
+ return -EFAULT;
+ }
+#endif
+
+ if (mm) {
+ if (phdr->p_flags & PF_X) {
+ if (!mm->start_code) {
+ mm->start_code = maddr;
+ mm->end_code = maddr + phdr->p_memsz;
+ }
+ } else if (!mm->start_data) {
+ mm->start_data = maddr;
+ mm->end_data = maddr + phdr->p_memsz;
+ }
+ }
+
+ seg++;
+ }
+
+ return 0;
+}
+
+/*****************************************************************************/
+/*
+ * ELF-FDPIC core dumper
+ *
+ * Modelled on fs/exec.c:aout_core_dump()
+ * Jeremy Fitzhardinge <jeremy@sw.oz.au>
+ *
+ * Modelled on fs/binfmt_elf.c core dumper
+ */
+#ifdef CONFIG_ELF_CORE
+
+/*
+ * 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, unsigned long mm_flags)
+{
+ int dump_ok;
+
+ /* Do not dump I/O mapped devices or special mappings */
+ if (vma->vm_flags & VM_IO) {
+ kdcore("%08lx: %08lx: no (IO)", vma->vm_start, vma->vm_flags);
+ return 0;
+ }
+
+ /* If we may not read the contents, don't allow us to dump
+ * them either. "dump_write()" can't handle it anyway.
+ */
+ if (!(vma->vm_flags & VM_READ)) {
+ kdcore("%08lx: %08lx: no (!read)", vma->vm_start, vma->vm_flags);
+ return 0;
+ }
+
+ /* support for DAX */
+ if (vma_is_dax(vma)) {
+ if (vma->vm_flags & VM_SHARED) {
+ dump_ok = test_bit(MMF_DUMP_DAX_SHARED, &mm_flags);
+ kdcore("%08lx: %08lx: %s (DAX shared)", vma->vm_start,
+ vma->vm_flags, dump_ok ? "yes" : "no");
+ } else {
+ dump_ok = test_bit(MMF_DUMP_DAX_PRIVATE, &mm_flags);
+ kdcore("%08lx: %08lx: %s (DAX private)", vma->vm_start,
+ vma->vm_flags, dump_ok ? "yes" : "no");
+ }
+ return dump_ok;
+ }
+
+ /* 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) {
+ dump_ok = test_bit(MMF_DUMP_ANON_SHARED, &mm_flags);
+ kdcore("%08lx: %08lx: %s (share)", vma->vm_start,
+ vma->vm_flags, dump_ok ? "yes" : "no");
+ return dump_ok;
+ }
+
+ dump_ok = test_bit(MMF_DUMP_MAPPED_SHARED, &mm_flags);
+ kdcore("%08lx: %08lx: %s (share)", vma->vm_start,
+ vma->vm_flags, dump_ok ? "yes" : "no");
+ return dump_ok;
+ }
+
+#ifdef CONFIG_MMU
+ /* By default, if it hasn't been written to, don't write it out */
+ if (!vma->anon_vma) {
+ dump_ok = test_bit(MMF_DUMP_MAPPED_PRIVATE, &mm_flags);
+ kdcore("%08lx: %08lx: %s (!anon)", vma->vm_start,
+ vma->vm_flags, dump_ok ? "yes" : "no");
+ return dump_ok;
+ }
+#endif
+
+ dump_ok = test_bit(MMF_DUMP_ANON_PRIVATE, &mm_flags);
+ kdcore("%08lx: %08lx: %s", vma->vm_start, vma->vm_flags,
+ dump_ok ? "yes" : "no");
+ return dump_ok;
+}
+
+/* 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 DEBUG */
+
+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 inline void fill_elf_fdpic_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_FDPIC_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, 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 inline 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);
+ prstatus->pr_utime = ns_to_timeval(cputime.utime);
+ prstatus->pr_stime = ns_to_timeval(cputime.stime);
+ } else {
+ u64 utime, stime;
+
+ task_cputime(p, &utime, &stime);
+ prstatus->pr_utime = ns_to_timeval(utime);
+ prstatus->pr_stime = ns_to_timeval(stime);
+ }
+ prstatus->pr_cutime = ns_to_timeval(p->signal->cutime);
+ prstatus->pr_cstime = ns_to_timeval(p->signal->cstime);
+
+ prstatus->pr_exec_fdpic_loadmap = p->mm->context.exec_fdpic_loadmap;
+ prstatus->pr_interp_fdpic_loadmap = p->mm->context.interp_fdpic_loadmap;
+}
+
+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;
+}
+
+/* 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 thread's 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)
+{
+ struct task_struct *p = t->thread;
+ int sz = 0;
+
+ 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]);
+
+ t->prstatus.pr_fpvalid = elf_core_copy_task_fpregs(p, NULL, &t->fpu);
+ if (t->prstatus.pr_fpvalid) {
+ 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;
+}
+
+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;
+}
+
+/*
+ * dump the segments for an MMU process
+ */
+static bool elf_fdpic_dump_segments(struct coredump_params *cprm)
+{
+ struct vm_area_struct *vma;
+
+ for (vma = current->mm->mmap; vma; vma = vma->vm_next) {
+#ifdef CONFIG_MMU
+ unsigned long addr;
+#endif
+
+ if (!maydump(vma, cprm->mm_flags))
+ continue;
+
+#ifdef CONFIG_MMU
+ for (addr = vma->vm_start; addr < vma->vm_end;
+ addr += PAGE_SIZE) {
+ bool res;
+ struct page *page = get_dump_page(addr);
+ if (page) {
+ void *kaddr = kmap(page);
+ res = dump_emit(cprm, kaddr, PAGE_SIZE);
+ kunmap(page);
+ put_page(page);
+ } else {
+ res = dump_skip(cprm, PAGE_SIZE);
+ }
+ if (!res)
+ return false;
+ }
+#else
+ if (!dump_emit(cprm, (void *) vma->vm_start,
+ vma->vm_end - vma->vm_start))
+ return false;
+#endif
+ }
+ return true;
+}
+
+static size_t elf_core_vma_data_size(unsigned long mm_flags)
+{
+ struct vm_area_struct *vma;
+ size_t size = 0;
+
+ for (vma = current->mm->mmap; vma; vma = vma->vm_next)
+ if (maydump(vma, mm_flags))
+ size += vma->vm_end - vma->vm_start;
+ return size;
+}
+
+/*
+ * 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_fdpic_core_dump(struct coredump_params *cprm)
+{
+#define NUM_NOTES 6
+ int has_dumped = 0;
+ mm_segment_t fs;
+ int segs;
+ int i;
+ struct vm_area_struct *vma;
+ struct elfhdr *elf = NULL;
+ loff_t offset = 0, dataoff;
+ int numnote;
+ struct memelfnote *notes = NULL;
+ struct elf_prstatus *prstatus = NULL; /* NT_PRSTATUS */
+ struct elf_prpsinfo *psinfo = NULL; /* NT_PRPSINFO */
+ 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;
+ struct elf_phdr *phdr4note = NULL;
+ struct elf_shdr *shdr4extnum = NULL;
+ Elf_Half e_phnum;
+ elf_addr_t e_shoff;
+ struct core_thread *ct;
+ struct elf_thread_status *tmp;
+
+ /*
+ * 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 = kzalloc(sizeof(*prstatus), GFP_KERNEL);
+ if (!prstatus)
+ goto cleanup;
+ psinfo = kmalloc(sizeof(*psinfo), GFP_KERNEL);
+ if (!psinfo)
+ goto cleanup;
+ notes = kmalloc_array(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
+
+ for (ct = current->mm->core_state->dumper.next;
+ ct; ct = ct->next) {
+ tmp = kzalloc(sizeof(*tmp), GFP_KERNEL);
+ if (!tmp)
+ goto cleanup;
+
+ tmp->thread = ct->task;
+ list_add(&tmp->list, &thread_list);
+ }
+
+ 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(cprm->siginfo->si_signo, tmp);
+ thread_status_size += sz;
+ }
+
+ /* now collect the dump for the current */
+ fill_prstatus(prstatus, current, cprm->siginfo->si_signo);
+ elf_core_copy_regs(&prstatus->pr_reg, cprm->regs);
+
+ segs = current->mm->map_count;
+ segs += elf_core_extra_phdrs();
+
+ /* 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;
+
+ /* Set up header */
+ fill_elf_fdpic_header(elf, e_phnum);
+
+ has_dumped = 1;
+ /*
+ * 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);
+
+ numnote = 2;
+
+ auxv = (elf_addr_t *) current->mm->saved_auxv;
+
+ i = 0;
+ do
+ i += 2;
+ while (auxv[i - 2] != AT_NULL);
+ fill_note(&notes[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, cprm->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", ELF_CORE_XFPREG_TYPE, sizeof(*xfpu), xfpu);
+#endif
+
+ fs = get_fs();
+ set_fs(KERNEL_DS);
+
+ offset += sizeof(*elf); /* Elf header */
+ offset += segs * sizeof(struct elf_phdr); /* Program headers */
+
+ /* Write notes phdr entry */
+ {
+ int sz = 0;
+
+ for (i = 0; i < numnote; i++)
+ sz += notesize(notes + i);
+
+ sz += thread_status_size;
+
+ phdr4note = kmalloc(sizeof(*phdr4note), GFP_KERNEL);
+ if (!phdr4note)
+ goto end_coredump;
+
+ fill_elf_note_phdr(phdr4note, sz, offset);
+ offset += sz;
+ }
+
+ /* Page-align dumped data */
+ dataoff = offset = roundup(offset, ELF_EXEC_PAGESIZE);
+
+ offset += elf_core_vma_data_size(cprm->mm_flags);
+ 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 (vma = current->mm->mmap; vma; 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, cprm->mm_flags) ? 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;
+
+ 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 */
+ for (i = 0; i < numnote; i++)
+ if (!writenote(notes + i, cprm))
+ 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], cprm))
+ goto end_coredump;
+ }
+
+ if (!dump_skip(cprm, dataoff - cprm->pos))
+ goto end_coredump;
+
+ if (!elf_fdpic_dump_segments(cprm))
+ 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;
+ }
+
+ if (cprm->file->f_pos != offset) {
+ /* Sanity check */
+ printk(KERN_WARNING
+ "elf_core_dump: file->f_pos (%lld) != offset (%lld)\n",
+ cprm->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(phdr4note);
+ kfree(elf);
+ kfree(prstatus);
+ kfree(psinfo);
+ kfree(notes);
+ kfree(fpu);
+ kfree(shdr4extnum);
+#ifdef ELF_CORE_COPY_XFPREGS
+ kfree(xfpu);
+#endif
+ return has_dumped;
+#undef NUM_NOTES
+}
+
+#endif /* CONFIG_ELF_CORE */