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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
commitace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch)
treeb2d64bc10158fdd5497876388cd68142ca374ed3 /fs/binfmt_elf.c
parentInitial commit. (diff)
downloadlinux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz
linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'fs/binfmt_elf.c')
-rw-r--r--fs/binfmt_elf.c2180
1 files changed, 2180 insertions, 0 deletions
diff --git a/fs/binfmt_elf.c b/fs/binfmt_elf.c
new file mode 100644
index 000000000..7b3d2d491
--- /dev/null
+++ b/fs/binfmt_elf.c
@@ -0,0 +1,2180 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * 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/log2.h>
+#include <linux/mm.h>
+#include <linux/mman.h>
+#include <linux/errno.h>
+#include <linux/signal.h>
+#include <linux/binfmts.h>
+#include <linux/string.h>
+#include <linux/file.h>
+#include <linux/slab.h>
+#include <linux/personality.h>
+#include <linux/elfcore.h>
+#include <linux/init.h>
+#include <linux/highuid.h>
+#include <linux/compiler.h>
+#include <linux/highmem.h>
+#include <linux/hugetlb.h>
+#include <linux/pagemap.h>
+#include <linux/vmalloc.h>
+#include <linux/security.h>
+#include <linux/random.h>
+#include <linux/elf.h>
+#include <linux/elf-randomize.h>
+#include <linux/utsname.h>
+#include <linux/coredump.h>
+#include <linux/sched.h>
+#include <linux/sched/coredump.h>
+#include <linux/sched/task_stack.h>
+#include <linux/sched/cputime.h>
+#include <linux/sizes.h>
+#include <linux/types.h>
+#include <linux/cred.h>
+#include <linux/dax.h>
+#include <linux/uaccess.h>
+#include <linux/rseq.h>
+#include <asm/param.h>
+#include <asm/page.h>
+
+#ifndef ELF_COMPAT
+#define ELF_COMPAT 0
+#endif
+
+#ifndef user_long_t
+#define user_long_t long
+#endif
+#ifndef user_siginfo_t
+#define user_siginfo_t siginfo_t
+#endif
+
+/* That's for binfmt_elf_fdpic to deal with */
+#ifndef elf_check_fdpic
+#define elf_check_fdpic(ex) false
+#endif
+
+static int load_elf_binary(struct linux_binprm *bprm);
+
+#ifdef CONFIG_USELIB
+static int load_elf_library(struct file *);
+#else
+#define load_elf_library NULL
+#endif
+
+/*
+ * If we don't support core dumping, then supply a NULL so we
+ * don't even try.
+ */
+#ifdef CONFIG_ELF_CORE
+static int elf_core_dump(struct coredump_params *cprm);
+#else
+#define elf_core_dump NULL
+#endif
+
+#if ELF_EXEC_PAGESIZE > PAGE_SIZE
+#define ELF_MIN_ALIGN ELF_EXEC_PAGESIZE
+#else
+#define ELF_MIN_ALIGN PAGE_SIZE
+#endif
+
+#ifndef ELF_CORE_EFLAGS
+#define ELF_CORE_EFLAGS 0
+#endif
+
+#define ELF_PAGESTART(_v) ((_v) & ~(int)(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,
+#ifdef CONFIG_COREDUMP
+ .core_dump = elf_core_dump,
+ .min_coredump = ELF_EXEC_PAGESIZE,
+#endif
+};
+
+#define BAD_ADDR(x) (unlikely((unsigned long)(x) >= TASK_SIZE))
+
+static int set_brk(unsigned long start, unsigned long end, int prot)
+{
+ start = ELF_PAGEALIGN(start);
+ end = ELF_PAGEALIGN(end);
+ if (end > start) {
+ /*
+ * Map the last of the bss segment.
+ * If the header is requesting these pages to be
+ * executable, honour that (ppc32 needs this).
+ */
+ int error = vm_brk_flags(start, end - start,
+ prot & PROT_EXEC ? VM_EXEC : 0);
+ if (error)
+ return error;
+ }
+ current->mm->start_brk = current->mm->brk = end;
+ return 0;
+}
+
+/* We need to explicitly zero any fractional pages
+ after the data section (i.e. bss). This would
+ contain the junk from the file that should not
+ be in memory
+ */
+static int padzero(unsigned long elf_bss)
+{
+ unsigned long nbyte;
+
+ nbyte = ELF_PAGEOFFSET(elf_bss);
+ if (nbyte) {
+ nbyte = ELF_MIN_ALIGN - nbyte;
+ if (clear_user((void __user *) elf_bss, nbyte))
+ return -EFAULT;
+ }
+ return 0;
+}
+
+/* Let's use some macros to make this stack manipulation a little clearer */
+#ifdef CONFIG_STACK_GROWSUP
+#define STACK_ADD(sp, items) ((elf_addr_t __user *)(sp) + (items))
+#define STACK_ROUND(sp, items) \
+ ((15 + (unsigned long) ((sp) + (items))) &~ 15UL)
+#define STACK_ALLOC(sp, len) ({ \
+ elf_addr_t __user *old_sp = (elf_addr_t __user *)sp; sp += len; \
+ old_sp; })
+#else
+#define STACK_ADD(sp, items) ((elf_addr_t __user *)(sp) - (items))
+#define STACK_ROUND(sp, items) \
+ (((unsigned long) (sp - items)) &~ 15UL)
+#define STACK_ALLOC(sp, len) (sp -= len)
+#endif
+
+#ifndef ELF_BASE_PLATFORM
+/*
+ * AT_BASE_PLATFORM indicates the "real" hardware/microarchitecture.
+ * If the arch defines ELF_BASE_PLATFORM (in asm/elf.h), the value
+ * will be copied to the user stack in the same manner as AT_PLATFORM.
+ */
+#define ELF_BASE_PLATFORM NULL
+#endif
+
+static int
+create_elf_tables(struct linux_binprm *bprm, const struct elfhdr *exec,
+ unsigned long interp_load_addr,
+ unsigned long e_entry, unsigned long phdr_addr)
+{
+ struct mm_struct *mm = current->mm;
+ unsigned long p = bprm->p;
+ int argc = bprm->argc;
+ int envc = bprm->envc;
+ elf_addr_t __user *sp;
+ elf_addr_t __user *u_platform;
+ elf_addr_t __user *u_base_platform;
+ elf_addr_t __user *u_rand_bytes;
+ const char *k_platform = ELF_PLATFORM;
+ const char *k_base_platform = ELF_BASE_PLATFORM;
+ unsigned char k_rand_bytes[16];
+ int items;
+ elf_addr_t *elf_info;
+ elf_addr_t flags = 0;
+ int ei_index;
+ const struct cred *cred = current_cred();
+ struct vm_area_struct *vma;
+
+ /*
+ * In some cases (e.g. Hyper-Threading), we want to avoid L1
+ * evictions by the processes running on the same package. One
+ * thing we can do is to shuffle the initial stack for them.
+ */
+
+ p = arch_align_stack(p);
+
+ /*
+ * If this architecture has a platform capability string, copy it
+ * to userspace. In some cases (Sparc), this info is impossible
+ * for userspace to get any other way, in others (i386) it is
+ * merely difficult.
+ */
+ u_platform = NULL;
+ if (k_platform) {
+ size_t len = strlen(k_platform) + 1;
+
+ u_platform = (elf_addr_t __user *)STACK_ALLOC(p, len);
+ if (copy_to_user(u_platform, k_platform, len))
+ return -EFAULT;
+ }
+
+ /*
+ * If this architecture has a "base" platform capability
+ * string, copy it to userspace.
+ */
+ u_base_platform = NULL;
+ if (k_base_platform) {
+ size_t len = strlen(k_base_platform) + 1;
+
+ u_base_platform = (elf_addr_t __user *)STACK_ALLOC(p, len);
+ if (copy_to_user(u_base_platform, k_base_platform, len))
+ return -EFAULT;
+ }
+
+ /*
+ * Generate 16 random bytes for userspace PRNG seeding.
+ */
+ get_random_bytes(k_rand_bytes, sizeof(k_rand_bytes));
+ u_rand_bytes = (elf_addr_t __user *)
+ STACK_ALLOC(p, sizeof(k_rand_bytes));
+ if (copy_to_user(u_rand_bytes, k_rand_bytes, sizeof(k_rand_bytes)))
+ return -EFAULT;
+
+ /* Create the ELF interpreter info */
+ elf_info = (elf_addr_t *)mm->saved_auxv;
+ /* update AT_VECTOR_SIZE_BASE if the number of NEW_AUX_ENT() changes */
+#define NEW_AUX_ENT(id, val) \
+ do { \
+ *elf_info++ = id; \
+ *elf_info++ = val; \
+ } while (0)
+
+#ifdef ARCH_DLINFO
+ /*
+ * ARCH_DLINFO must come first so PPC can do its special alignment of
+ * AUXV.
+ * update AT_VECTOR_SIZE_ARCH if the number of NEW_AUX_ENT() in
+ * ARCH_DLINFO changes
+ */
+ ARCH_DLINFO;
+#endif
+ NEW_AUX_ENT(AT_HWCAP, ELF_HWCAP);
+ NEW_AUX_ENT(AT_PAGESZ, ELF_EXEC_PAGESIZE);
+ NEW_AUX_ENT(AT_CLKTCK, CLOCKS_PER_SEC);
+ NEW_AUX_ENT(AT_PHDR, phdr_addr);
+ 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);
+ if (bprm->interp_flags & BINPRM_FLAGS_PRESERVE_ARGV0)
+ flags |= AT_FLAGS_PRESERVE_ARGV0;
+ NEW_AUX_ENT(AT_FLAGS, flags);
+ NEW_AUX_ENT(AT_ENTRY, e_entry);
+ NEW_AUX_ENT(AT_UID, from_kuid_munged(cred->user_ns, cred->uid));
+ NEW_AUX_ENT(AT_EUID, from_kuid_munged(cred->user_ns, cred->euid));
+ NEW_AUX_ENT(AT_GID, from_kgid_munged(cred->user_ns, cred->gid));
+ NEW_AUX_ENT(AT_EGID, from_kgid_munged(cred->user_ns, cred->egid));
+ NEW_AUX_ENT(AT_SECURE, bprm->secureexec);
+ NEW_AUX_ENT(AT_RANDOM, (elf_addr_t)(unsigned long)u_rand_bytes);
+#ifdef ELF_HWCAP2
+ NEW_AUX_ENT(AT_HWCAP2, ELF_HWCAP2);
+#endif
+ NEW_AUX_ENT(AT_EXECFN, bprm->exec);
+ if (k_platform) {
+ NEW_AUX_ENT(AT_PLATFORM,
+ (elf_addr_t)(unsigned long)u_platform);
+ }
+ if (k_base_platform) {
+ NEW_AUX_ENT(AT_BASE_PLATFORM,
+ (elf_addr_t)(unsigned long)u_base_platform);
+ }
+ if (bprm->have_execfd) {
+ NEW_AUX_ENT(AT_EXECFD, bprm->execfd);
+ }
+#ifdef CONFIG_RSEQ
+ NEW_AUX_ENT(AT_RSEQ_FEATURE_SIZE, offsetof(struct rseq, end));
+ NEW_AUX_ENT(AT_RSEQ_ALIGN, __alignof__(struct rseq));
+#endif
+#undef NEW_AUX_ENT
+ /* AT_NULL is zero; clear the rest too */
+ memset(elf_info, 0, (char *)mm->saved_auxv +
+ sizeof(mm->saved_auxv) - (char *)elf_info);
+
+ /* And advance past the AT_NULL entry. */
+ elf_info += 2;
+
+ ei_index = elf_info - (elf_addr_t *)mm->saved_auxv;
+ sp = STACK_ADD(p, ei_index);
+
+ items = (argc + 1) + (envc + 1) + 1;
+ bprm->p = STACK_ROUND(sp, items);
+
+ /* Point sp at the lowest address on the stack */
+#ifdef CONFIG_STACK_GROWSUP
+ sp = (elf_addr_t __user *)bprm->p - items - ei_index;
+ bprm->exec = (unsigned long)sp; /* XXX: PARISC HACK */
+#else
+ sp = (elf_addr_t __user *)bprm->p;
+#endif
+
+
+ /*
+ * Grow the stack manually; some architectures have a limit on how
+ * far ahead a user-space access may be in order to grow the stack.
+ */
+ if (mmap_write_lock_killable(mm))
+ return -EINTR;
+ vma = find_extend_vma_locked(mm, bprm->p);
+ mmap_write_unlock(mm);
+ if (!vma)
+ return -EFAULT;
+
+ /* Now, let's put argc (and argv, envp if appropriate) on the stack */
+ if (put_user(argc, sp++))
+ return -EFAULT;
+
+ /* Populate list of argv pointers back to argv strings. */
+ p = mm->arg_end = mm->arg_start;
+ while (argc-- > 0) {
+ size_t len;
+ if (put_user((elf_addr_t)p, sp++))
+ return -EFAULT;
+ len = strnlen_user((void __user *)p, MAX_ARG_STRLEN);
+ if (!len || len > MAX_ARG_STRLEN)
+ return -EINVAL;
+ p += len;
+ }
+ if (put_user(0, sp++))
+ return -EFAULT;
+ mm->arg_end = p;
+
+ /* Populate list of envp pointers back to envp strings. */
+ mm->env_end = mm->env_start = p;
+ while (envc-- > 0) {
+ size_t len;
+ if (put_user((elf_addr_t)p, sp++))
+ return -EFAULT;
+ len = strnlen_user((void __user *)p, MAX_ARG_STRLEN);
+ if (!len || len > MAX_ARG_STRLEN)
+ return -EINVAL;
+ p += len;
+ }
+ if (put_user(0, sp++))
+ return -EFAULT;
+ mm->env_end = p;
+
+ /* Put the elf_info on the stack in the right place. */
+ if (copy_to_user(sp, mm->saved_auxv, ei_index * sizeof(elf_addr_t)))
+ return -EFAULT;
+ return 0;
+}
+
+static unsigned long elf_map(struct file *filep, unsigned long addr,
+ const struct elf_phdr *eppnt, int prot, int type,
+ unsigned long total_size)
+{
+ unsigned long map_addr;
+ unsigned long size = eppnt->p_filesz + ELF_PAGEOFFSET(eppnt->p_vaddr);
+ unsigned long off = eppnt->p_offset - ELF_PAGEOFFSET(eppnt->p_vaddr);
+ addr = ELF_PAGESTART(addr);
+ size = ELF_PAGEALIGN(size);
+
+ /* mmap() will return -EINVAL if given a zero size, but a
+ * segment with zero filesize is perfectly valid */
+ if (!size)
+ return addr;
+
+ /*
+ * total_size is the size of the ELF (interpreter) image.
+ * The _first_ mmap needs to know the full size, otherwise
+ * randomization might put this image into an overlapping
+ * position with the ELF binary image. (since size < total_size)
+ * So we first map the 'big' image - and unmap the remainder at
+ * the end. (which unmap is needed for ELF images with holes.)
+ */
+ if (total_size) {
+ total_size = ELF_PAGEALIGN(total_size);
+ map_addr = vm_mmap(filep, addr, total_size, prot, type, off);
+ if (!BAD_ADDR(map_addr))
+ vm_munmap(map_addr+size, total_size-size);
+ } else
+ map_addr = vm_mmap(filep, addr, size, prot, type, off);
+
+ if ((type & MAP_FIXED_NOREPLACE) &&
+ PTR_ERR((void *)map_addr) == -EEXIST)
+ pr_info("%d (%s): Uhuuh, elf segment at %px requested but the memory is mapped already\n",
+ task_pid_nr(current), current->comm, (void *)addr);
+
+ return(map_addr);
+}
+
+static unsigned long total_mapping_size(const struct elf_phdr *phdr, int nr)
+{
+ elf_addr_t min_addr = -1;
+ elf_addr_t max_addr = 0;
+ bool pt_load = false;
+ int i;
+
+ for (i = 0; i < nr; i++) {
+ if (phdr[i].p_type == PT_LOAD) {
+ min_addr = min(min_addr, ELF_PAGESTART(phdr[i].p_vaddr));
+ max_addr = max(max_addr, phdr[i].p_vaddr + phdr[i].p_memsz);
+ pt_load = true;
+ }
+ }
+ return pt_load ? (max_addr - min_addr) : 0;
+}
+
+static int elf_read(struct file *file, void *buf, size_t len, loff_t pos)
+{
+ ssize_t rv;
+
+ rv = kernel_read(file, buf, len, &pos);
+ if (unlikely(rv != len)) {
+ return (rv < 0) ? rv : -EIO;
+ }
+ return 0;
+}
+
+static unsigned long maximum_alignment(struct elf_phdr *cmds, int nr)
+{
+ unsigned long alignment = 0;
+ int i;
+
+ for (i = 0; i < nr; i++) {
+ if (cmds[i].p_type == PT_LOAD) {
+ unsigned long p_align = cmds[i].p_align;
+
+ /* skip non-power of two alignments as invalid */
+ if (!is_power_of_2(p_align))
+ continue;
+ alignment = max(alignment, p_align);
+ }
+ }
+
+ /* ensure we align to at least one page */
+ return ELF_PAGEALIGN(alignment);
+}
+
+/**
+ * load_elf_phdrs() - load ELF program headers
+ * @elf_ex: ELF header of the binary whose program headers should be loaded
+ * @elf_file: the opened ELF binary file
+ *
+ * Loads ELF program headers from the binary file elf_file, which has the ELF
+ * header pointed to by elf_ex, into a newly allocated array. The caller is
+ * responsible for freeing the allocated data. Returns NULL upon failure.
+ */
+static struct elf_phdr *load_elf_phdrs(const struct elfhdr *elf_ex,
+ struct file *elf_file)
+{
+ struct elf_phdr *elf_phdata = NULL;
+ int retval = -1;
+ unsigned int size;
+
+ /*
+ * If the size of this structure has changed, then punt, since
+ * we will be doing the wrong thing.
+ */
+ if (elf_ex->e_phentsize != sizeof(struct elf_phdr))
+ goto out;
+
+ /* Sanity check the number of program headers... */
+ /* ...and their total size. */
+ size = sizeof(struct elf_phdr) * elf_ex->e_phnum;
+ if (size == 0 || size > 65536 || size > ELF_MIN_ALIGN)
+ goto out;
+
+ elf_phdata = kmalloc(size, GFP_KERNEL);
+ if (!elf_phdata)
+ goto out;
+
+ /* Read in the program headers */
+ retval = elf_read(elf_file, elf_phdata, size, elf_ex->e_phoff);
+
+out:
+ if (retval) {
+ kfree(elf_phdata);
+ elf_phdata = NULL;
+ }
+ return elf_phdata;
+}
+
+#ifndef CONFIG_ARCH_BINFMT_ELF_STATE
+
+/**
+ * struct arch_elf_state - arch-specific ELF loading state
+ *
+ * This structure is used to preserve architecture specific data during
+ * the loading of an ELF file, throughout the checking of architecture
+ * specific ELF headers & through to the point where the ELF load is
+ * known to be proceeding (ie. SET_PERSONALITY).
+ *
+ * This implementation is a dummy for architectures which require no
+ * specific state.
+ */
+struct arch_elf_state {
+};
+
+#define INIT_ARCH_ELF_STATE {}
+
+/**
+ * arch_elf_pt_proc() - check a PT_LOPROC..PT_HIPROC ELF program header
+ * @ehdr: The main ELF header
+ * @phdr: The program header to check
+ * @elf: The open ELF file
+ * @is_interp: True if the phdr is from the interpreter of the ELF being
+ * loaded, else false.
+ * @state: Architecture-specific state preserved throughout the process
+ * of loading the ELF.
+ *
+ * Inspects the program header phdr to validate its correctness and/or
+ * suitability for the system. Called once per ELF program header in the
+ * range PT_LOPROC to PT_HIPROC, for both the ELF being loaded and its
+ * interpreter.
+ *
+ * Return: Zero to proceed with the ELF load, non-zero to fail the ELF load
+ * with that return code.
+ */
+static inline int arch_elf_pt_proc(struct elfhdr *ehdr,
+ struct elf_phdr *phdr,
+ struct file *elf, bool is_interp,
+ struct arch_elf_state *state)
+{
+ /* Dummy implementation, always proceed */
+ return 0;
+}
+
+/**
+ * arch_check_elf() - check an ELF executable
+ * @ehdr: The main ELF header
+ * @has_interp: True if the ELF has an interpreter, else false.
+ * @interp_ehdr: The interpreter's ELF header
+ * @state: Architecture-specific state preserved throughout the process
+ * of loading the ELF.
+ *
+ * Provides a final opportunity for architecture code to reject the loading
+ * of the ELF & cause an exec syscall to return an error. This is called after
+ * all program headers to be checked by arch_elf_pt_proc have been.
+ *
+ * Return: Zero to proceed with the ELF load, non-zero to fail the ELF load
+ * with that return code.
+ */
+static inline int arch_check_elf(struct elfhdr *ehdr, bool has_interp,
+ struct elfhdr *interp_ehdr,
+ struct arch_elf_state *state)
+{
+ /* Dummy implementation, always proceed */
+ return 0;
+}
+
+#endif /* !CONFIG_ARCH_BINFMT_ELF_STATE */
+
+static inline int make_prot(u32 p_flags, struct arch_elf_state *arch_state,
+ bool has_interp, bool is_interp)
+{
+ int prot = 0;
+
+ if (p_flags & PF_R)
+ prot |= PROT_READ;
+ if (p_flags & PF_W)
+ prot |= PROT_WRITE;
+ if (p_flags & PF_X)
+ prot |= PROT_EXEC;
+
+ return arch_elf_adjust_prot(prot, arch_state, has_interp, is_interp);
+}
+
+/* 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 no_base, struct elf_phdr *interp_elf_phdata,
+ struct arch_elf_state *arch_state)
+{
+ struct elf_phdr *eppnt;
+ unsigned long load_addr = 0;
+ int load_addr_set = 0;
+ unsigned long last_bss = 0, elf_bss = 0;
+ int bss_prot = 0;
+ unsigned long error = ~0UL;
+ unsigned long total_size;
+ int i;
+
+ /* First of all, some simple consistency checks */
+ if (interp_elf_ex->e_type != ET_EXEC &&
+ interp_elf_ex->e_type != ET_DYN)
+ goto out;
+ if (!elf_check_arch(interp_elf_ex) ||
+ elf_check_fdpic(interp_elf_ex))
+ goto out;
+ if (!interpreter->f_op->mmap)
+ goto out;
+
+ total_size = total_mapping_size(interp_elf_phdata,
+ interp_elf_ex->e_phnum);
+ if (!total_size) {
+ error = -EINVAL;
+ goto out;
+ }
+
+ eppnt = interp_elf_phdata;
+ for (i = 0; i < interp_elf_ex->e_phnum; i++, eppnt++) {
+ if (eppnt->p_type == PT_LOAD) {
+ int elf_type = MAP_PRIVATE;
+ int elf_prot = make_prot(eppnt->p_flags, arch_state,
+ true, true);
+ unsigned long vaddr = 0;
+ unsigned long k, map_addr;
+
+ vaddr = eppnt->p_vaddr;
+ if (interp_elf_ex->e_type == ET_EXEC || load_addr_set)
+ elf_type |= MAP_FIXED;
+ else if (no_base && interp_elf_ex->e_type == ET_DYN)
+ load_addr = -vaddr;
+
+ map_addr = elf_map(interpreter, load_addr + vaddr,
+ eppnt, elf_prot, elf_type, total_size);
+ total_size = 0;
+ error = map_addr;
+ if (BAD_ADDR(map_addr))
+ goto out;
+
+ if (!load_addr_set &&
+ interp_elf_ex->e_type == ET_DYN) {
+ load_addr = map_addr - ELF_PAGESTART(vaddr);
+ load_addr_set = 1;
+ }
+
+ /*
+ * Check to see if the section's size will overflow the
+ * allowed task size. Note that p_filesz must always be
+ * <= p_memsize so it's only necessary to check p_memsz.
+ */
+ k = load_addr + eppnt->p_vaddr;
+ if (BAD_ADDR(k) ||
+ eppnt->p_filesz > eppnt->p_memsz ||
+ eppnt->p_memsz > TASK_SIZE ||
+ TASK_SIZE - eppnt->p_memsz < k) {
+ error = -ENOMEM;
+ goto out;
+ }
+
+ /*
+ * Find the end of the file mapping for this phdr, and
+ * keep track of the largest address we see for this.
+ */
+ k = load_addr + eppnt->p_vaddr + eppnt->p_filesz;
+ if (k > elf_bss)
+ elf_bss = k;
+
+ /*
+ * Do the same thing for the memory mapping - between
+ * elf_bss and last_bss is the bss section.
+ */
+ k = load_addr + eppnt->p_vaddr + eppnt->p_memsz;
+ if (k > last_bss) {
+ last_bss = k;
+ bss_prot = elf_prot;
+ }
+ }
+ }
+
+ /*
+ * Now fill out the bss section: first pad the last page from
+ * the file up to the page boundary, and zero it from elf_bss
+ * up to the end of the page.
+ */
+ if (padzero(elf_bss)) {
+ error = -EFAULT;
+ goto out;
+ }
+ /*
+ * Next, align both the file and mem bss up to the page size,
+ * since this is where elf_bss was just zeroed up to, and where
+ * last_bss will end after the vm_brk_flags() below.
+ */
+ elf_bss = ELF_PAGEALIGN(elf_bss);
+ last_bss = ELF_PAGEALIGN(last_bss);
+ /* Finally, if there is still more bss to allocate, do it. */
+ if (last_bss > elf_bss) {
+ error = vm_brk_flags(elf_bss, last_bss - elf_bss,
+ bss_prot & PROT_EXEC ? VM_EXEC : 0);
+ if (error)
+ goto out;
+ }
+
+ error = load_addr;
+out:
+ return error;
+}
+
+/*
+ * These are the functions used to load ELF style executables and shared
+ * libraries. There is no binary dependent code anywhere else.
+ */
+
+static int parse_elf_property(const char *data, size_t *off, size_t datasz,
+ struct arch_elf_state *arch,
+ bool have_prev_type, u32 *prev_type)
+{
+ size_t o, step;
+ const struct gnu_property *pr;
+ int ret;
+
+ if (*off == datasz)
+ return -ENOENT;
+
+ if (WARN_ON_ONCE(*off > datasz || *off % ELF_GNU_PROPERTY_ALIGN))
+ return -EIO;
+ o = *off;
+ datasz -= *off;
+
+ if (datasz < sizeof(*pr))
+ return -ENOEXEC;
+ pr = (const struct gnu_property *)(data + o);
+ o += sizeof(*pr);
+ datasz -= sizeof(*pr);
+
+ if (pr->pr_datasz > datasz)
+ return -ENOEXEC;
+
+ WARN_ON_ONCE(o % ELF_GNU_PROPERTY_ALIGN);
+ step = round_up(pr->pr_datasz, ELF_GNU_PROPERTY_ALIGN);
+ if (step > datasz)
+ return -ENOEXEC;
+
+ /* Properties are supposed to be unique and sorted on pr_type: */
+ if (have_prev_type && pr->pr_type <= *prev_type)
+ return -ENOEXEC;
+ *prev_type = pr->pr_type;
+
+ ret = arch_parse_elf_property(pr->pr_type, data + o,
+ pr->pr_datasz, ELF_COMPAT, arch);
+ if (ret)
+ return ret;
+
+ *off = o + step;
+ return 0;
+}
+
+#define NOTE_DATA_SZ SZ_1K
+#define GNU_PROPERTY_TYPE_0_NAME "GNU"
+#define NOTE_NAME_SZ (sizeof(GNU_PROPERTY_TYPE_0_NAME))
+
+static int parse_elf_properties(struct file *f, const struct elf_phdr *phdr,
+ struct arch_elf_state *arch)
+{
+ union {
+ struct elf_note nhdr;
+ char data[NOTE_DATA_SZ];
+ } note;
+ loff_t pos;
+ ssize_t n;
+ size_t off, datasz;
+ int ret;
+ bool have_prev_type;
+ u32 prev_type;
+
+ if (!IS_ENABLED(CONFIG_ARCH_USE_GNU_PROPERTY) || !phdr)
+ return 0;
+
+ /* load_elf_binary() shouldn't call us unless this is true... */
+ if (WARN_ON_ONCE(phdr->p_type != PT_GNU_PROPERTY))
+ return -ENOEXEC;
+
+ /* If the properties are crazy large, that's too bad (for now): */
+ if (phdr->p_filesz > sizeof(note))
+ return -ENOEXEC;
+
+ pos = phdr->p_offset;
+ n = kernel_read(f, &note, phdr->p_filesz, &pos);
+
+ BUILD_BUG_ON(sizeof(note) < sizeof(note.nhdr) + NOTE_NAME_SZ);
+ if (n < 0 || n < sizeof(note.nhdr) + NOTE_NAME_SZ)
+ return -EIO;
+
+ if (note.nhdr.n_type != NT_GNU_PROPERTY_TYPE_0 ||
+ note.nhdr.n_namesz != NOTE_NAME_SZ ||
+ strncmp(note.data + sizeof(note.nhdr),
+ GNU_PROPERTY_TYPE_0_NAME, n - sizeof(note.nhdr)))
+ return -ENOEXEC;
+
+ off = round_up(sizeof(note.nhdr) + NOTE_NAME_SZ,
+ ELF_GNU_PROPERTY_ALIGN);
+ if (off > n)
+ return -ENOEXEC;
+
+ if (note.nhdr.n_descsz > n - off)
+ return -ENOEXEC;
+ datasz = off + note.nhdr.n_descsz;
+
+ have_prev_type = false;
+ do {
+ ret = parse_elf_property(note.data, &off, datasz, arch,
+ have_prev_type, &prev_type);
+ have_prev_type = true;
+ } while (!ret);
+
+ return ret == -ENOENT ? 0 : ret;
+}
+
+static int load_elf_binary(struct linux_binprm *bprm)
+{
+ struct file *interpreter = NULL; /* to shut gcc up */
+ unsigned long load_bias = 0, phdr_addr = 0;
+ int first_pt_load = 1;
+ unsigned long error;
+ struct elf_phdr *elf_ppnt, *elf_phdata, *interp_elf_phdata = NULL;
+ struct elf_phdr *elf_property_phdata = NULL;
+ unsigned long elf_bss, elf_brk;
+ int bss_prot = 0;
+ int retval, i;
+ unsigned long elf_entry;
+ unsigned long e_entry;
+ unsigned long interp_load_addr = 0;
+ unsigned long start_code, end_code, start_data, end_data;
+ unsigned long reloc_func_desc __maybe_unused = 0;
+ int executable_stack = EXSTACK_DEFAULT;
+ struct elfhdr *elf_ex = (struct elfhdr *)bprm->buf;
+ struct elfhdr *interp_elf_ex = NULL;
+ struct arch_elf_state arch_state = INIT_ARCH_ELF_STATE;
+ struct mm_struct *mm;
+ struct pt_regs *regs;
+
+ retval = -ENOEXEC;
+ /* First of all, some simple consistency checks */
+ if (memcmp(elf_ex->e_ident, ELFMAG, SELFMAG) != 0)
+ goto out;
+
+ if (elf_ex->e_type != ET_EXEC && elf_ex->e_type != ET_DYN)
+ goto out;
+ if (!elf_check_arch(elf_ex))
+ goto out;
+ if (elf_check_fdpic(elf_ex))
+ goto out;
+ if (!bprm->file->f_op->mmap)
+ goto out;
+
+ elf_phdata = load_elf_phdrs(elf_ex, bprm->file);
+ if (!elf_phdata)
+ goto out;
+
+ elf_ppnt = elf_phdata;
+ for (i = 0; i < elf_ex->e_phnum; i++, elf_ppnt++) {
+ char *elf_interpreter;
+
+ if (elf_ppnt->p_type == PT_GNU_PROPERTY) {
+ elf_property_phdata = elf_ppnt;
+ continue;
+ }
+
+ if (elf_ppnt->p_type != PT_INTERP)
+ continue;
+
+ /*
+ * This is the program interpreter used for shared libraries -
+ * for now assume that this is an a.out format binary.
+ */
+ retval = -ENOEXEC;
+ if (elf_ppnt->p_filesz > PATH_MAX || elf_ppnt->p_filesz < 2)
+ goto out_free_ph;
+
+ retval = -ENOMEM;
+ elf_interpreter = kmalloc(elf_ppnt->p_filesz, GFP_KERNEL);
+ if (!elf_interpreter)
+ goto out_free_ph;
+
+ retval = elf_read(bprm->file, elf_interpreter, elf_ppnt->p_filesz,
+ elf_ppnt->p_offset);
+ if (retval < 0)
+ goto out_free_interp;
+ /* make sure path is NULL terminated */
+ retval = -ENOEXEC;
+ if (elf_interpreter[elf_ppnt->p_filesz - 1] != '\0')
+ goto out_free_interp;
+
+ interpreter = open_exec(elf_interpreter);
+ kfree(elf_interpreter);
+ retval = PTR_ERR(interpreter);
+ if (IS_ERR(interpreter))
+ goto out_free_ph;
+
+ /*
+ * If the binary is not readable then enforce mm->dumpable = 0
+ * regardless of the interpreter's permissions.
+ */
+ would_dump(bprm, interpreter);
+
+ interp_elf_ex = kmalloc(sizeof(*interp_elf_ex), GFP_KERNEL);
+ if (!interp_elf_ex) {
+ retval = -ENOMEM;
+ goto out_free_file;
+ }
+
+ /* Get the exec headers */
+ retval = elf_read(interpreter, interp_elf_ex,
+ sizeof(*interp_elf_ex), 0);
+ if (retval < 0)
+ goto out_free_dentry;
+
+ break;
+
+out_free_interp:
+ kfree(elf_interpreter);
+ goto out_free_ph;
+ }
+
+ elf_ppnt = elf_phdata;
+ for (i = 0; i < elf_ex->e_phnum; i++, elf_ppnt++)
+ switch (elf_ppnt->p_type) {
+ case PT_GNU_STACK:
+ if (elf_ppnt->p_flags & PF_X)
+ executable_stack = EXSTACK_ENABLE_X;
+ else
+ executable_stack = EXSTACK_DISABLE_X;
+ break;
+
+ case PT_LOPROC ... PT_HIPROC:
+ retval = arch_elf_pt_proc(elf_ex, elf_ppnt,
+ bprm->file, false,
+ &arch_state);
+ if (retval)
+ goto out_free_dentry;
+ break;
+ }
+
+ /* Some simple consistency checks for the interpreter */
+ if (interpreter) {
+ retval = -ELIBBAD;
+ /* Not an ELF interpreter */
+ if (memcmp(interp_elf_ex->e_ident, ELFMAG, SELFMAG) != 0)
+ goto out_free_dentry;
+ /* Verify the interpreter has a valid arch */
+ if (!elf_check_arch(interp_elf_ex) ||
+ elf_check_fdpic(interp_elf_ex))
+ goto out_free_dentry;
+
+ /* Load the interpreter program headers */
+ interp_elf_phdata = load_elf_phdrs(interp_elf_ex,
+ interpreter);
+ if (!interp_elf_phdata)
+ goto out_free_dentry;
+
+ /* Pass PT_LOPROC..PT_HIPROC headers to arch code */
+ elf_property_phdata = NULL;
+ elf_ppnt = interp_elf_phdata;
+ for (i = 0; i < interp_elf_ex->e_phnum; i++, elf_ppnt++)
+ switch (elf_ppnt->p_type) {
+ case PT_GNU_PROPERTY:
+ elf_property_phdata = elf_ppnt;
+ break;
+
+ case PT_LOPROC ... PT_HIPROC:
+ retval = arch_elf_pt_proc(interp_elf_ex,
+ elf_ppnt, interpreter,
+ true, &arch_state);
+ if (retval)
+ goto out_free_dentry;
+ break;
+ }
+ }
+
+ retval = parse_elf_properties(interpreter ?: bprm->file,
+ elf_property_phdata, &arch_state);
+ if (retval)
+ goto out_free_dentry;
+
+ /*
+ * Allow arch code to reject the ELF at this point, whilst it's
+ * still possible to return an error to the code that invoked
+ * the exec syscall.
+ */
+ retval = arch_check_elf(elf_ex,
+ !!interpreter, interp_elf_ex,
+ &arch_state);
+ if (retval)
+ goto out_free_dentry;
+
+ /* Flush all traces of the currently running executable */
+ retval = begin_new_exec(bprm);
+ if (retval)
+ goto out_free_dentry;
+
+ /* Do this immediately, since STACK_TOP as used in setup_arg_pages
+ may depend on the personality. */
+ SET_PERSONALITY2(*elf_ex, &arch_state);
+ if (elf_read_implies_exec(*elf_ex, executable_stack))
+ current->personality |= READ_IMPLIES_EXEC;
+
+ if (!(current->personality & ADDR_NO_RANDOMIZE) && randomize_va_space)
+ current->flags |= PF_RANDOMIZE;
+
+ setup_new_exec(bprm);
+
+ /* Do this so that we can load the interpreter, if need be. We will
+ change some of these later */
+ retval = setup_arg_pages(bprm, randomize_stack_top(STACK_TOP),
+ executable_stack);
+ if (retval < 0)
+ goto out_free_dentry;
+
+ elf_bss = 0;
+ elf_brk = 0;
+
+ start_code = ~0UL;
+ end_code = 0;
+ start_data = 0;
+ end_data = 0;
+
+ /* Now we do a little grungy work by mmapping the ELF image into
+ the correct location in memory. */
+ for(i = 0, elf_ppnt = elf_phdata;
+ i < elf_ex->e_phnum; i++, elf_ppnt++) {
+ int elf_prot, elf_flags;
+ unsigned long k, vaddr;
+ unsigned long total_size = 0;
+ unsigned long alignment;
+
+ 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,
+ bss_prot);
+ if (retval)
+ goto out_free_dentry;
+ nbyte = ELF_PAGEOFFSET(elf_bss);
+ if (nbyte) {
+ nbyte = ELF_MIN_ALIGN - nbyte;
+ if (nbyte > elf_brk - elf_bss)
+ nbyte = elf_brk - elf_bss;
+ if (clear_user((void __user *)elf_bss +
+ load_bias, nbyte)) {
+ /*
+ * This bss-zeroing can fail if the ELF
+ * file specifies odd protections. So
+ * we don't check the return value
+ */
+ }
+ }
+ }
+
+ elf_prot = make_prot(elf_ppnt->p_flags, &arch_state,
+ !!interpreter, false);
+
+ elf_flags = MAP_PRIVATE;
+
+ vaddr = elf_ppnt->p_vaddr;
+ /*
+ * The first time through the loop, first_pt_load is true:
+ * layout will be calculated. Once set, use MAP_FIXED since
+ * we know we've already safely mapped the entire region with
+ * MAP_FIXED_NOREPLACE in the once-per-binary logic following.
+ */
+ if (!first_pt_load) {
+ elf_flags |= MAP_FIXED;
+ } else if (elf_ex->e_type == ET_EXEC) {
+ /*
+ * This logic is run once for the first LOAD Program
+ * Header for ET_EXEC binaries. No special handling
+ * is needed.
+ */
+ elf_flags |= MAP_FIXED_NOREPLACE;
+ } else if (elf_ex->e_type == ET_DYN) {
+ /*
+ * This logic is run once for the first LOAD Program
+ * Header for ET_DYN binaries to calculate the
+ * randomization (load_bias) for all the LOAD
+ * Program Headers.
+ *
+ * There are effectively two types of ET_DYN
+ * binaries: programs (i.e. PIE: ET_DYN with INTERP)
+ * and loaders (ET_DYN without INTERP, since they
+ * _are_ the ELF interpreter). The loaders must
+ * be loaded away from programs since the program
+ * may otherwise collide with the loader (especially
+ * for ET_EXEC which does not have a randomized
+ * position). For example to handle invocations of
+ * "./ld.so someprog" to test out a new version of
+ * the loader, the subsequent program that the
+ * loader loads must avoid the loader itself, so
+ * they cannot share the same load range. Sufficient
+ * room for the brk must be allocated with the
+ * loader as well, since brk must be available with
+ * the loader.
+ *
+ * Therefore, programs are loaded offset from
+ * ELF_ET_DYN_BASE and loaders are loaded into the
+ * independently randomized mmap region (0 load_bias
+ * without MAP_FIXED nor MAP_FIXED_NOREPLACE).
+ */
+ if (interpreter) {
+ load_bias = ELF_ET_DYN_BASE;
+ if (current->flags & PF_RANDOMIZE)
+ load_bias += arch_mmap_rnd();
+ alignment = maximum_alignment(elf_phdata, elf_ex->e_phnum);
+ if (alignment)
+ load_bias &= ~(alignment - 1);
+ elf_flags |= MAP_FIXED_NOREPLACE;
+ } else
+ load_bias = 0;
+
+ /*
+ * Since load_bias is used for all subsequent loading
+ * calculations, we must lower it by the first vaddr
+ * so that the remaining calculations based on the
+ * ELF vaddrs will be correctly offset. The result
+ * is then page aligned.
+ */
+ load_bias = ELF_PAGESTART(load_bias - vaddr);
+
+ /*
+ * Calculate the entire size of the ELF mapping
+ * (total_size), used for the initial mapping,
+ * due to load_addr_set which is set to true later
+ * once the initial mapping is performed.
+ *
+ * Note that this is only sensible when the LOAD
+ * segments are contiguous (or overlapping). If
+ * used for LOADs that are far apart, this would
+ * cause the holes between LOADs to be mapped,
+ * running the risk of having the mapping fail,
+ * as it would be larger than the ELF file itself.
+ *
+ * As a result, only ET_DYN does this, since
+ * some ET_EXEC (e.g. ia64) may have large virtual
+ * memory holes between LOADs.
+ *
+ */
+ total_size = total_mapping_size(elf_phdata,
+ elf_ex->e_phnum);
+ if (!total_size) {
+ retval = -EINVAL;
+ goto out_free_dentry;
+ }
+ }
+
+ error = elf_map(bprm->file, load_bias + vaddr, elf_ppnt,
+ elf_prot, elf_flags, total_size);
+ if (BAD_ADDR(error)) {
+ retval = IS_ERR_VALUE(error) ?
+ PTR_ERR((void*)error) : -EINVAL;
+ goto out_free_dentry;
+ }
+
+ if (first_pt_load) {
+ first_pt_load = 0;
+ if (elf_ex->e_type == ET_DYN) {
+ load_bias += error -
+ ELF_PAGESTART(load_bias + vaddr);
+ reloc_func_desc = load_bias;
+ }
+ }
+
+ /*
+ * Figure out which segment in the file contains the Program
+ * Header table, and map to the associated memory address.
+ */
+ if (elf_ppnt->p_offset <= elf_ex->e_phoff &&
+ elf_ex->e_phoff < elf_ppnt->p_offset + elf_ppnt->p_filesz) {
+ phdr_addr = elf_ex->e_phoff - elf_ppnt->p_offset +
+ elf_ppnt->p_vaddr;
+ }
+
+ k = elf_ppnt->p_vaddr;
+ if ((elf_ppnt->p_flags & PF_X) && k < start_code)
+ start_code = k;
+ if (start_data < k)
+ start_data = k;
+
+ /*
+ * Check to see if the section's size will overflow the
+ * allowed task size. Note that p_filesz must always be
+ * <= p_memsz so it is only necessary to check p_memsz.
+ */
+ if (BAD_ADDR(k) || elf_ppnt->p_filesz > elf_ppnt->p_memsz ||
+ elf_ppnt->p_memsz > TASK_SIZE ||
+ TASK_SIZE - elf_ppnt->p_memsz < k) {
+ /* set_brk can never work. Avoid overflows. */
+ retval = -EINVAL;
+ goto out_free_dentry;
+ }
+
+ k = elf_ppnt->p_vaddr + elf_ppnt->p_filesz;
+
+ if (k > elf_bss)
+ elf_bss = k;
+ if ((elf_ppnt->p_flags & PF_X) && end_code < k)
+ end_code = k;
+ if (end_data < k)
+ end_data = k;
+ k = elf_ppnt->p_vaddr + elf_ppnt->p_memsz;
+ if (k > elf_brk) {
+ bss_prot = elf_prot;
+ elf_brk = k;
+ }
+ }
+
+ e_entry = elf_ex->e_entry + load_bias;
+ phdr_addr += 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, bss_prot);
+ if (retval)
+ goto out_free_dentry;
+ if (likely(elf_bss != elf_brk) && unlikely(padzero(elf_bss))) {
+ retval = -EFAULT; /* Nobody gets to see this, but.. */
+ goto out_free_dentry;
+ }
+
+ if (interpreter) {
+ elf_entry = load_elf_interp(interp_elf_ex,
+ interpreter,
+ load_bias, interp_elf_phdata,
+ &arch_state);
+ if (!IS_ERR_VALUE(elf_entry)) {
+ /*
+ * load_elf_interp() returns relocation
+ * adjustment
+ */
+ interp_load_addr = elf_entry;
+ elf_entry += interp_elf_ex->e_entry;
+ }
+ if (BAD_ADDR(elf_entry)) {
+ retval = IS_ERR_VALUE(elf_entry) ?
+ (int)elf_entry : -EINVAL;
+ goto out_free_dentry;
+ }
+ reloc_func_desc = interp_load_addr;
+
+ allow_write_access(interpreter);
+ fput(interpreter);
+
+ kfree(interp_elf_ex);
+ kfree(interp_elf_phdata);
+ } else {
+ elf_entry = e_entry;
+ if (BAD_ADDR(elf_entry)) {
+ retval = -EINVAL;
+ goto out_free_dentry;
+ }
+ }
+
+ kfree(elf_phdata);
+
+ set_binfmt(&elf_format);
+
+#ifdef ARCH_HAS_SETUP_ADDITIONAL_PAGES
+ retval = ARCH_SETUP_ADDITIONAL_PAGES(bprm, elf_ex, !!interpreter);
+ if (retval < 0)
+ goto out;
+#endif /* ARCH_HAS_SETUP_ADDITIONAL_PAGES */
+
+ retval = create_elf_tables(bprm, elf_ex, interp_load_addr,
+ e_entry, phdr_addr);
+ if (retval < 0)
+ goto out;
+
+ mm = current->mm;
+ mm->end_code = end_code;
+ mm->start_code = start_code;
+ mm->start_data = start_data;
+ mm->end_data = end_data;
+ mm->start_stack = bprm->p;
+
+ if ((current->flags & PF_RANDOMIZE) && (randomize_va_space > 1)) {
+ /*
+ * For architectures with ELF randomization, when executing
+ * a loader directly (i.e. no interpreter listed in ELF
+ * headers), move the brk area out of the mmap region
+ * (since it grows up, and may collide early with the stack
+ * growing down), and into the unused ELF_ET_DYN_BASE region.
+ */
+ if (IS_ENABLED(CONFIG_ARCH_HAS_ELF_RANDOMIZE) &&
+ elf_ex->e_type == ET_DYN && !interpreter) {
+ mm->brk = mm->start_brk = ELF_ET_DYN_BASE;
+ }
+
+ mm->brk = mm->start_brk = arch_randomize_brk(mm);
+#ifdef compat_brk_randomized
+ current->brk_randomized = 1;
+#endif
+ }
+
+ if (current->personality & MMAP_PAGE_ZERO) {
+ /* Why this, you ask??? Well SVr4 maps page 0 as read-only,
+ and some applications "depend" upon this behavior.
+ Since we do not have the power to recompile these, we
+ emulate the SVr4 behavior. Sigh. */
+ error = vm_mmap(NULL, 0, PAGE_SIZE, PROT_READ | PROT_EXEC,
+ MAP_FIXED | MAP_PRIVATE, 0);
+ }
+
+ regs = current_pt_regs();
+#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
+
+ finalize_exec(bprm);
+ START_THREAD(elf_ex, regs, elf_entry, bprm->p);
+ retval = 0;
+out:
+ return retval;
+
+ /* error cleanup */
+out_free_dentry:
+ kfree(interp_elf_ex);
+ kfree(interp_elf_phdata);
+out_free_file:
+ allow_write_access(interpreter);
+ if (interpreter)
+ fput(interpreter);
+out_free_ph:
+ kfree(elf_phdata);
+ goto out;
+}
+
+#ifdef CONFIG_USELIB
+/* This is really simpleminded and specialized - we are loading an
+ a.out library that is given an ELF header. */
+static int load_elf_library(struct file *file)
+{
+ struct elf_phdr *elf_phdata;
+ struct elf_phdr *eppnt;
+ unsigned long elf_bss, bss, len;
+ int retval, error, i, j;
+ struct elfhdr elf_ex;
+
+ error = -ENOEXEC;
+ retval = elf_read(file, &elf_ex, sizeof(elf_ex), 0);
+ if (retval < 0)
+ goto out;
+
+ if (memcmp(elf_ex.e_ident, ELFMAG, SELFMAG) != 0)
+ goto out;
+
+ /* First of all, some simple consistency checks */
+ if (elf_ex.e_type != ET_EXEC || elf_ex.e_phnum > 2 ||
+ !elf_check_arch(&elf_ex) || !file->f_op->mmap)
+ goto out;
+ if (elf_check_fdpic(&elf_ex))
+ 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 = elf_read(file, eppnt, j, elf_ex.e_phoff);
+ if (retval < 0)
+ goto out_free_ph;
+
+ for (j = 0, i = 0; i<elf_ex.e_phnum; i++)
+ if ((eppnt + i)->p_type == PT_LOAD)
+ j++;
+ if (j != 1)
+ goto out_free_ph;
+
+ while (eppnt->p_type != PT_LOAD)
+ eppnt++;
+
+ /* Now use mmap to map the library into memory. */
+ error = vm_mmap(file,
+ ELF_PAGESTART(eppnt->p_vaddr),
+ (eppnt->p_filesz +
+ ELF_PAGEOFFSET(eppnt->p_vaddr)),
+ PROT_READ | PROT_WRITE | PROT_EXEC,
+ MAP_FIXED_NOREPLACE | MAP_PRIVATE,
+ (eppnt->p_offset -
+ ELF_PAGEOFFSET(eppnt->p_vaddr)));
+ if (error != ELF_PAGESTART(eppnt->p_vaddr))
+ goto out_free_ph;
+
+ elf_bss = eppnt->p_vaddr + eppnt->p_filesz;
+ if (padzero(elf_bss)) {
+ error = -EFAULT;
+ goto out_free_ph;
+ }
+
+ len = ELF_PAGEALIGN(eppnt->p_filesz + eppnt->p_vaddr);
+ bss = ELF_PAGEALIGN(eppnt->p_memsz + eppnt->p_vaddr);
+ if (bss > len) {
+ error = vm_brk(len, bss - len);
+ if (error)
+ goto out_free_ph;
+ }
+ error = 0;
+
+out_free_ph:
+ kfree(elf_phdata);
+out:
+ return error;
+}
+#endif /* #ifdef CONFIG_USELIB */
+
+#ifdef CONFIG_ELF_CORE
+/*
+ * ELF core dumper
+ *
+ * Modelled on fs/exec.c:aout_core_dump()
+ * Jeremy Fitzhardinge <jeremy@sw.oz.au>
+ */
+
+/* An ELF note in memory */
+struct memelfnote
+{
+ const char *name;
+ int type;
+ unsigned int datasz;
+ void *data;
+};
+
+static int notesize(struct memelfnote *en)
+{
+ int sz;
+
+ sz = sizeof(struct elf_note);
+ sz += roundup(strlen(en->name) + 1, 4);
+ sz += roundup(en->datasz, 4);
+
+ return sz;
+}
+
+static int writenote(struct memelfnote *men, struct coredump_params *cprm)
+{
+ struct elf_note en;
+ en.n_namesz = strlen(men->name) + 1;
+ en.n_descsz = men->datasz;
+ en.n_type = men->type;
+
+ return dump_emit(cprm, &en, sizeof(en)) &&
+ dump_emit(cprm, men->name, en.n_namesz) && dump_align(cprm, 4) &&
+ dump_emit(cprm, men->data, men->datasz) && dump_align(cprm, 4);
+}
+
+static void fill_elf_header(struct elfhdr *elf, int segs,
+ u16 machine, u32 flags)
+{
+ memset(elf, 0, sizeof(*elf));
+
+ memcpy(elf->e_ident, ELFMAG, SELFMAG);
+ elf->e_ident[EI_CLASS] = ELF_CLASS;
+ elf->e_ident[EI_DATA] = ELF_DATA;
+ elf->e_ident[EI_VERSION] = EV_CURRENT;
+ elf->e_ident[EI_OSABI] = ELF_OSABI;
+
+ elf->e_type = ET_CORE;
+ elf->e_machine = machine;
+ elf->e_version = EV_CURRENT;
+ elf->e_phoff = sizeof(struct elfhdr);
+ elf->e_flags = flags;
+ elf->e_ehsize = sizeof(struct elfhdr);
+ elf->e_phentsize = sizeof(struct elf_phdr);
+ elf->e_phnum = segs;
+}
+
+static void fill_elf_note_phdr(struct elf_phdr *phdr, int sz, loff_t offset)
+{
+ phdr->p_type = PT_NOTE;
+ phdr->p_offset = offset;
+ phdr->p_vaddr = 0;
+ phdr->p_paddr = 0;
+ phdr->p_filesz = sz;
+ phdr->p_memsz = 0;
+ phdr->p_flags = 0;
+ phdr->p_align = 4;
+}
+
+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;
+}
+
+/*
+ * 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_common *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_kernel_old_timeval(cputime.utime);
+ prstatus->pr_stime = ns_to_kernel_old_timeval(cputime.stime);
+ } else {
+ u64 utime, stime;
+
+ task_cputime(p, &utime, &stime);
+ prstatus->pr_utime = ns_to_kernel_old_timeval(utime);
+ prstatus->pr_stime = ns_to_kernel_old_timeval(stime);
+ }
+
+ prstatus->pr_cutime = ns_to_kernel_old_timeval(p->signal->cutime);
+ prstatus->pr_cstime = ns_to_kernel_old_timeval(p->signal->cstime);
+}
+
+static int fill_psinfo(struct elf_prpsinfo *psinfo, struct task_struct *p,
+ struct mm_struct *mm)
+{
+ const struct cred *cred;
+ unsigned int i, len;
+ unsigned int state;
+
+ /* 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);
+
+ state = READ_ONCE(p->__state);
+ i = state ? ffz(~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();
+ get_task_comm(psinfo->pr_fname, p);
+
+ return 0;
+}
+
+static void fill_auxv_note(struct memelfnote *note, struct mm_struct *mm)
+{
+ elf_addr_t *auxv = (elf_addr_t *) mm->saved_auxv;
+ int i = 0;
+ do
+ i += 2;
+ while (auxv[i - 2] != AT_NULL);
+ fill_note(note, "CORE", NT_AUXV, i * sizeof(elf_addr_t), auxv);
+}
+
+static void fill_siginfo_note(struct memelfnote *note, user_siginfo_t *csigdata,
+ const kernel_siginfo_t *siginfo)
+{
+ copy_siginfo_to_external(csigdata, siginfo);
+ fill_note(note, "CORE", NT_SIGINFO, sizeof(*csigdata), csigdata);
+}
+
+#define MAX_FILE_NOTE_SIZE (4*1024*1024)
+/*
+ * Format of NT_FILE note:
+ *
+ * long count -- how many files are mapped
+ * long page_size -- units for file_ofs
+ * array of [COUNT] elements of
+ * long start
+ * long end
+ * long file_ofs
+ * followed by COUNT filenames in ASCII: "FILE1" NUL "FILE2" NUL...
+ */
+static int fill_files_note(struct memelfnote *note, struct coredump_params *cprm)
+{
+ unsigned count, size, names_ofs, remaining, n;
+ user_long_t *data;
+ user_long_t *start_end_ofs;
+ char *name_base, *name_curpos;
+ int i;
+
+ /* *Estimated* file count and total data size needed */
+ count = cprm->vma_count;
+ if (count > UINT_MAX / 64)
+ return -EINVAL;
+ size = count * 64;
+
+ names_ofs = (2 + 3 * count) * sizeof(data[0]);
+ alloc:
+ if (size >= MAX_FILE_NOTE_SIZE) /* paranoia check */
+ return -EINVAL;
+ size = round_up(size, PAGE_SIZE);
+ /*
+ * "size" can be 0 here legitimately.
+ * Let it ENOMEM and omit NT_FILE section which will be empty anyway.
+ */
+ data = kvmalloc(size, GFP_KERNEL);
+ if (ZERO_OR_NULL_PTR(data))
+ return -ENOMEM;
+
+ start_end_ofs = data + 2;
+ name_base = name_curpos = ((char *)data) + names_ofs;
+ remaining = size - names_ofs;
+ count = 0;
+ for (i = 0; i < cprm->vma_count; i++) {
+ struct core_vma_metadata *m = &cprm->vma_meta[i];
+ struct file *file;
+ const char *filename;
+
+ file = m->file;
+ if (!file)
+ continue;
+ filename = file_path(file, name_curpos, remaining);
+ if (IS_ERR(filename)) {
+ if (PTR_ERR(filename) == -ENAMETOOLONG) {
+ kvfree(data);
+ size = size * 5 / 4;
+ goto alloc;
+ }
+ continue;
+ }
+
+ /* file_path() fills at the end, move name down */
+ /* n = strlen(filename) + 1: */
+ n = (name_curpos + remaining) - filename;
+ remaining = filename - name_curpos;
+ memmove(name_curpos, filename, n);
+ name_curpos += n;
+
+ *start_end_ofs++ = m->start;
+ *start_end_ofs++ = m->end;
+ *start_end_ofs++ = m->pgoff;
+ count++;
+ }
+
+ /* Now we know exact count of files, can store it */
+ data[0] = count;
+ data[1] = PAGE_SIZE;
+ /*
+ * Count usually is less than mm->map_count,
+ * we need to move filenames down.
+ */
+ n = cprm->vma_count - count;
+ if (n != 0) {
+ unsigned shift_bytes = n * 3 * sizeof(data[0]);
+ memmove(name_base - shift_bytes, name_base,
+ name_curpos - name_base);
+ name_curpos -= shift_bytes;
+ }
+
+ size = name_curpos - (char *)data;
+ fill_note(note, "CORE", NT_FILE, size, data);
+ return 0;
+}
+
+#include <linux/regset.h>
+
+struct elf_thread_core_info {
+ struct elf_thread_core_info *next;
+ struct task_struct *task;
+ struct elf_prstatus prstatus;
+ struct memelfnote notes[];
+};
+
+struct elf_note_info {
+ struct elf_thread_core_info *thread;
+ struct memelfnote psinfo;
+ struct memelfnote signote;
+ struct memelfnote auxv;
+ struct memelfnote files;
+ user_siginfo_t csigdata;
+ size_t size;
+ int thread_notes;
+};
+
+#ifdef CORE_DUMP_USE_REGSET
+/*
+ * When a regset has a writeback hook, we call it on each thread before
+ * dumping user memory. On register window machines, this makes sure the
+ * user memory backing the register data is up to date before we read it.
+ */
+static void do_thread_regset_writeback(struct task_struct *task,
+ const struct user_regset *regset)
+{
+ if (regset->writeback)
+ regset->writeback(task, regset, 1);
+}
+
+#ifndef PRSTATUS_SIZE
+#define PRSTATUS_SIZE sizeof(struct elf_prstatus)
+#endif
+
+#ifndef SET_PR_FPVALID
+#define SET_PR_FPVALID(S) ((S)->pr_fpvalid = 1)
+#endif
+
+static int fill_thread_core_info(struct elf_thread_core_info *t,
+ const struct user_regset_view *view,
+ long signr, struct elf_note_info *info)
+{
+ unsigned int note_iter, view_iter;
+
+ /*
+ * NT_PRSTATUS is the one special case, because the regset data
+ * goes into the pr_reg field inside the note contents, rather
+ * than being the whole note contents. We fill the regset in here.
+ * We assume that regset 0 is NT_PRSTATUS.
+ */
+ fill_prstatus(&t->prstatus.common, t->task, signr);
+ regset_get(t->task, &view->regsets[0],
+ sizeof(t->prstatus.pr_reg), &t->prstatus.pr_reg);
+
+ fill_note(&t->notes[0], "CORE", NT_PRSTATUS,
+ PRSTATUS_SIZE, &t->prstatus);
+ info->size += notesize(&t->notes[0]);
+
+ do_thread_regset_writeback(t->task, &view->regsets[0]);
+
+ /*
+ * Each other regset might generate a note too. For each regset
+ * that has no core_note_type or is inactive, skip it.
+ */
+ note_iter = 1;
+ for (view_iter = 1; view_iter < view->n; ++view_iter) {
+ const struct user_regset *regset = &view->regsets[view_iter];
+ int note_type = regset->core_note_type;
+ bool is_fpreg = note_type == NT_PRFPREG;
+ void *data;
+ int ret;
+
+ do_thread_regset_writeback(t->task, regset);
+ if (!note_type) // not for coredumps
+ continue;
+ if (regset->active && regset->active(t->task, regset) <= 0)
+ continue;
+
+ ret = regset_get_alloc(t->task, regset, ~0U, &data);
+ if (ret < 0)
+ continue;
+
+ if (WARN_ON_ONCE(note_iter >= info->thread_notes))
+ break;
+
+ if (is_fpreg)
+ SET_PR_FPVALID(&t->prstatus);
+
+ fill_note(&t->notes[note_iter], is_fpreg ? "CORE" : "LINUX",
+ note_type, ret, data);
+
+ info->size += notesize(&t->notes[note_iter]);
+ note_iter++;
+ }
+
+ return 1;
+}
+#else
+static int fill_thread_core_info(struct elf_thread_core_info *t,
+ const struct user_regset_view *view,
+ long signr, struct elf_note_info *info)
+{
+ struct task_struct *p = t->task;
+ elf_fpregset_t *fpu;
+
+ fill_prstatus(&t->prstatus.common, 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));
+ info->size += notesize(&t->notes[0]);
+
+ fpu = kzalloc(sizeof(elf_fpregset_t), GFP_KERNEL);
+ if (!fpu || !elf_core_copy_task_fpregs(p, fpu)) {
+ kfree(fpu);
+ return 1;
+ }
+
+ t->prstatus.pr_fpvalid = 1;
+ fill_note(&t->notes[1], "CORE", NT_PRFPREG, sizeof(*fpu), fpu);
+ info->size += notesize(&t->notes[1]);
+
+ return 1;
+}
+#endif
+
+static int fill_note_info(struct elfhdr *elf, int phdrs,
+ struct elf_note_info *info,
+ struct coredump_params *cprm)
+{
+ struct task_struct *dump_task = current;
+ const struct user_regset_view *view;
+ struct elf_thread_core_info *t;
+ struct elf_prpsinfo *psinfo;
+ struct core_thread *ct;
+
+ psinfo = kmalloc(sizeof(*psinfo), GFP_KERNEL);
+ if (!psinfo)
+ return 0;
+ fill_note(&info->psinfo, "CORE", NT_PRPSINFO, sizeof(*psinfo), psinfo);
+
+#ifdef CORE_DUMP_USE_REGSET
+ view = task_user_regset_view(dump_task);
+
+ /*
+ * Figure out how many notes we're going to need for each thread.
+ */
+ info->thread_notes = 0;
+ for (int i = 0; i < view->n; ++i)
+ if (view->regsets[i].core_note_type != 0)
+ ++info->thread_notes;
+
+ /*
+ * Sanity check. We rely on regset 0 being in NT_PRSTATUS,
+ * since it is our one special case.
+ */
+ if (unlikely(info->thread_notes == 0) ||
+ unlikely(view->regsets[0].core_note_type != NT_PRSTATUS)) {
+ WARN_ON(1);
+ return 0;
+ }
+
+ /*
+ * Initialize the ELF file header.
+ */
+ fill_elf_header(elf, phdrs,
+ view->e_machine, view->e_flags);
+#else
+ view = NULL;
+ info->thread_notes = 2;
+ fill_elf_header(elf, phdrs, ELF_ARCH, ELF_CORE_EFLAGS);
+#endif
+
+ /*
+ * Allocate a structure for each thread.
+ */
+ info->thread = kzalloc(offsetof(struct elf_thread_core_info,
+ notes[info->thread_notes]),
+ GFP_KERNEL);
+ if (unlikely(!info->thread))
+ return 0;
+
+ info->thread->task = dump_task;
+ for (ct = dump_task->signal->core_state->dumper.next; ct; ct = ct->next) {
+ t = kzalloc(offsetof(struct elf_thread_core_info,
+ notes[info->thread_notes]),
+ GFP_KERNEL);
+ if (unlikely(!t))
+ return 0;
+
+ t->task = ct->task;
+ t->next = info->thread->next;
+ info->thread->next = t;
+ }
+
+ /*
+ * Now fill in each thread's information.
+ */
+ for (t = info->thread; t != NULL; t = t->next)
+ if (!fill_thread_core_info(t, view, cprm->siginfo->si_signo, info))
+ return 0;
+
+ /*
+ * Fill in the two process-wide notes.
+ */
+ fill_psinfo(psinfo, dump_task->group_leader, dump_task->mm);
+ info->size += notesize(&info->psinfo);
+
+ fill_siginfo_note(&info->signote, &info->csigdata, cprm->siginfo);
+ info->size += notesize(&info->signote);
+
+ fill_auxv_note(&info->auxv, current->mm);
+ info->size += notesize(&info->auxv);
+
+ if (fill_files_note(&info->files, cprm) == 0)
+ info->size += notesize(&info->files);
+
+ return 1;
+}
+
+/*
+ * Write all the notes for each thread. When writing the first thread, the
+ * process-wide notes are interleaved after the first thread-specific note.
+ */
+static int write_note_info(struct elf_note_info *info,
+ struct coredump_params *cprm)
+{
+ bool first = true;
+ struct elf_thread_core_info *t = info->thread;
+
+ do {
+ int i;
+
+ if (!writenote(&t->notes[0], cprm))
+ return 0;
+
+ if (first && !writenote(&info->psinfo, cprm))
+ return 0;
+ if (first && !writenote(&info->signote, cprm))
+ return 0;
+ if (first && !writenote(&info->auxv, cprm))
+ return 0;
+ if (first && info->files.data &&
+ !writenote(&info->files, cprm))
+ return 0;
+
+ for (i = 1; i < info->thread_notes; ++i)
+ if (t->notes[i].data &&
+ !writenote(&t->notes[i], cprm))
+ return 0;
+
+ first = false;
+ t = t->next;
+ } while (t);
+
+ return 1;
+}
+
+static void free_note_info(struct elf_note_info *info)
+{
+ struct elf_thread_core_info *threads = info->thread;
+ while (threads) {
+ unsigned int i;
+ struct elf_thread_core_info *t = threads;
+ threads = t->next;
+ WARN_ON(t->notes[0].data && t->notes[0].data != &t->prstatus);
+ for (i = 1; i < info->thread_notes; ++i)
+ kfree(t->notes[i].data);
+ kfree(t);
+ }
+ kfree(info->psinfo.data);
+ kvfree(info->files.data);
+}
+
+static void fill_extnum_info(struct elfhdr *elf, struct elf_shdr *shdr4extnum,
+ elf_addr_t e_shoff, int segs)
+{
+ elf->e_shoff = e_shoff;
+ elf->e_shentsize = sizeof(*shdr4extnum);
+ elf->e_shnum = 1;
+ elf->e_shstrndx = SHN_UNDEF;
+
+ memset(shdr4extnum, 0, sizeof(*shdr4extnum));
+
+ shdr4extnum->sh_type = SHT_NULL;
+ shdr4extnum->sh_size = elf->e_shnum;
+ shdr4extnum->sh_link = elf->e_shstrndx;
+ shdr4extnum->sh_info = segs;
+}
+
+/*
+ * Actual dumper
+ *
+ * This is a two-pass process; first we find the offsets of the bits,
+ * and then they are actually written out. If we run out of core limit
+ * we just truncate.
+ */
+static int elf_core_dump(struct coredump_params *cprm)
+{
+ int has_dumped = 0;
+ int segs, i;
+ struct elfhdr elf;
+ loff_t offset = 0, dataoff;
+ struct elf_note_info info = { };
+ struct elf_phdr *phdr4note = NULL;
+ struct elf_shdr *shdr4extnum = NULL;
+ Elf_Half e_phnum;
+ elf_addr_t e_shoff;
+
+ /*
+ * The number of segs are recored into ELF header as 16bit value.
+ * Please check DEFAULT_MAX_MAP_COUNT definition when you modify here.
+ */
+ segs = cprm->vma_count + elf_core_extra_phdrs(cprm);
+
+ /* for notes section */
+ segs++;
+
+ /* If segs > PN_XNUM(0xffff), then e_phnum overflows. To avoid
+ * this, kernel supports extended numbering. Have a look at
+ * include/linux/elf.h for further information. */
+ e_phnum = segs > PN_XNUM ? PN_XNUM : segs;
+
+ /*
+ * Collect all the non-memory information about the process for the
+ * notes. This also sets up the file header.
+ */
+ if (!fill_note_info(&elf, e_phnum, &info, cprm))
+ goto end_coredump;
+
+ has_dumped = 1;
+
+ offset += sizeof(elf); /* ELF header */
+ offset += segs * sizeof(struct elf_phdr); /* Program headers */
+
+ /* Write notes phdr entry */
+ {
+ size_t sz = info.size;
+
+ /* For cell spufs */
+ sz += elf_coredump_extra_notes_size();
+
+ phdr4note = kmalloc(sizeof(*phdr4note), GFP_KERNEL);
+ if (!phdr4note)
+ goto end_coredump;
+
+ fill_elf_note_phdr(phdr4note, sz, offset);
+ offset += sz;
+ }
+
+ dataoff = offset = roundup(offset, ELF_EXEC_PAGESIZE);
+
+ offset += cprm->vma_data_size;
+ offset += elf_core_extra_data_size(cprm);
+ e_shoff = offset;
+
+ if (e_phnum == PN_XNUM) {
+ shdr4extnum = kmalloc(sizeof(*shdr4extnum), GFP_KERNEL);
+ if (!shdr4extnum)
+ goto end_coredump;
+ fill_extnum_info(&elf, shdr4extnum, e_shoff, segs);
+ }
+
+ offset = dataoff;
+
+ if (!dump_emit(cprm, &elf, sizeof(elf)))
+ goto end_coredump;
+
+ if (!dump_emit(cprm, phdr4note, sizeof(*phdr4note)))
+ goto end_coredump;
+
+ /* Write program headers for segments dump */
+ for (i = 0; i < cprm->vma_count; i++) {
+ struct core_vma_metadata *meta = cprm->vma_meta + i;
+ struct elf_phdr phdr;
+
+ phdr.p_type = PT_LOAD;
+ phdr.p_offset = offset;
+ phdr.p_vaddr = meta->start;
+ phdr.p_paddr = 0;
+ phdr.p_filesz = meta->dump_size;
+ phdr.p_memsz = meta->end - meta->start;
+ offset += phdr.p_filesz;
+ phdr.p_flags = 0;
+ if (meta->flags & VM_READ)
+ phdr.p_flags |= PF_R;
+ if (meta->flags & VM_WRITE)
+ phdr.p_flags |= PF_W;
+ if (meta->flags & VM_EXEC)
+ phdr.p_flags |= PF_X;
+ phdr.p_align = ELF_EXEC_PAGESIZE;
+
+ if (!dump_emit(cprm, &phdr, sizeof(phdr)))
+ goto end_coredump;
+ }
+
+ if (!elf_core_write_extra_phdrs(cprm, offset))
+ goto end_coredump;
+
+ /* write out the notes section */
+ if (!write_note_info(&info, cprm))
+ goto end_coredump;
+
+ /* For cell spufs */
+ if (elf_coredump_extra_notes_write(cprm))
+ goto end_coredump;
+
+ /* Align to page */
+ dump_skip_to(cprm, dataoff);
+
+ for (i = 0; i < cprm->vma_count; i++) {
+ struct core_vma_metadata *meta = cprm->vma_meta + i;
+
+ if (!dump_user_range(cprm, meta->start, meta->dump_size))
+ goto end_coredump;
+ }
+
+ if (!elf_core_write_extra_data(cprm))
+ goto end_coredump;
+
+ if (e_phnum == PN_XNUM) {
+ if (!dump_emit(cprm, shdr4extnum, sizeof(*shdr4extnum)))
+ goto end_coredump;
+ }
+
+end_coredump:
+ free_note_info(&info);
+ kfree(shdr4extnum);
+ kfree(phdr4note);
+ return has_dumped;
+}
+
+#endif /* CONFIG_ELF_CORE */
+
+static int __init init_elf_binfmt(void)
+{
+ register_binfmt(&elf_format);
+ return 0;
+}
+
+static void __exit exit_elf_binfmt(void)
+{
+ /* Remove the COFF and ELF loaders. */
+ unregister_binfmt(&elf_format);
+}
+
+core_initcall(init_elf_binfmt);
+module_exit(exit_elf_binfmt);
+
+#ifdef CONFIG_BINFMT_ELF_KUNIT_TEST
+#include "binfmt_elf_test.c"
+#endif