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https://github.com/AuxXxilium/linux_dsm_epyc7002.git
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1b5d783c94
new helper: would_dump(bprm, file). Checks if we are allowed to read the file and if we are not - sets ENFORCE_NODUMP. Exported, used in places that previously open-coded the same logics. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2083 lines
54 KiB
C
2083 lines
54 KiB
C
/*
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* linux/fs/binfmt_elf.c
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*
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* These are the functions used to load ELF format executables as used
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* on SVr4 machines. Information on the format may be found in the book
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* "UNIX SYSTEM V RELEASE 4 Programmers Guide: Ansi C and Programming Support
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* Tools".
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*
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* Copyright 1993, 1994: Eric Youngdale (ericy@cais.com).
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*/
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#include <linux/module.h>
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#include <linux/kernel.h>
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#include <linux/fs.h>
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#include <linux/mm.h>
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#include <linux/mman.h>
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#include <linux/errno.h>
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#include <linux/signal.h>
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#include <linux/binfmts.h>
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#include <linux/string.h>
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#include <linux/file.h>
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#include <linux/slab.h>
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#include <linux/personality.h>
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#include <linux/elfcore.h>
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#include <linux/init.h>
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#include <linux/highuid.h>
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#include <linux/compiler.h>
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#include <linux/highmem.h>
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#include <linux/pagemap.h>
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#include <linux/security.h>
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#include <linux/random.h>
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#include <linux/elf.h>
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#include <linux/utsname.h>
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#include <linux/coredump.h>
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#include <asm/uaccess.h>
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#include <asm/param.h>
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#include <asm/page.h>
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static int load_elf_binary(struct linux_binprm *bprm, struct pt_regs *regs);
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static int load_elf_library(struct file *);
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static unsigned long elf_map(struct file *, unsigned long, struct elf_phdr *,
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int, int, unsigned long);
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/*
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* If we don't support core dumping, then supply a NULL so we
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* don't even try.
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*/
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#ifdef CONFIG_ELF_CORE
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static int elf_core_dump(struct coredump_params *cprm);
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#else
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#define elf_core_dump NULL
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#endif
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#if ELF_EXEC_PAGESIZE > PAGE_SIZE
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#define ELF_MIN_ALIGN ELF_EXEC_PAGESIZE
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#else
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#define ELF_MIN_ALIGN PAGE_SIZE
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#endif
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#ifndef ELF_CORE_EFLAGS
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#define ELF_CORE_EFLAGS 0
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#endif
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#define ELF_PAGESTART(_v) ((_v) & ~(unsigned long)(ELF_MIN_ALIGN-1))
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#define ELF_PAGEOFFSET(_v) ((_v) & (ELF_MIN_ALIGN-1))
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#define ELF_PAGEALIGN(_v) (((_v) + ELF_MIN_ALIGN - 1) & ~(ELF_MIN_ALIGN - 1))
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static struct linux_binfmt elf_format = {
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.module = THIS_MODULE,
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.load_binary = load_elf_binary,
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.load_shlib = load_elf_library,
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.core_dump = elf_core_dump,
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.min_coredump = ELF_EXEC_PAGESIZE,
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};
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#define BAD_ADDR(x) ((unsigned long)(x) >= TASK_SIZE)
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static int set_brk(unsigned long start, unsigned long end)
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{
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start = ELF_PAGEALIGN(start);
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end = ELF_PAGEALIGN(end);
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if (end > start) {
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unsigned long addr;
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down_write(¤t->mm->mmap_sem);
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addr = do_brk(start, end - start);
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up_write(¤t->mm->mmap_sem);
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if (BAD_ADDR(addr))
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return addr;
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}
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current->mm->start_brk = current->mm->brk = end;
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return 0;
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}
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/* We need to explicitly zero any fractional pages
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after the data section (i.e. bss). This would
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contain the junk from the file that should not
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be in memory
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*/
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static int padzero(unsigned long elf_bss)
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{
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unsigned long nbyte;
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nbyte = ELF_PAGEOFFSET(elf_bss);
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if (nbyte) {
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nbyte = ELF_MIN_ALIGN - nbyte;
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if (clear_user((void __user *) elf_bss, nbyte))
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return -EFAULT;
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}
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return 0;
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}
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/* Let's use some macros to make this stack manipulation a little clearer */
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#ifdef CONFIG_STACK_GROWSUP
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#define STACK_ADD(sp, items) ((elf_addr_t __user *)(sp) + (items))
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#define STACK_ROUND(sp, items) \
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((15 + (unsigned long) ((sp) + (items))) &~ 15UL)
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#define STACK_ALLOC(sp, len) ({ \
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elf_addr_t __user *old_sp = (elf_addr_t __user *)sp; sp += len; \
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old_sp; })
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#else
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#define STACK_ADD(sp, items) ((elf_addr_t __user *)(sp) - (items))
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#define STACK_ROUND(sp, items) \
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(((unsigned long) (sp - items)) &~ 15UL)
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#define STACK_ALLOC(sp, len) ({ sp -= len ; sp; })
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#endif
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#ifndef ELF_BASE_PLATFORM
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/*
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* AT_BASE_PLATFORM indicates the "real" hardware/microarchitecture.
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* If the arch defines ELF_BASE_PLATFORM (in asm/elf.h), the value
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* will be copied to the user stack in the same manner as AT_PLATFORM.
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*/
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#define ELF_BASE_PLATFORM NULL
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#endif
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static int
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create_elf_tables(struct linux_binprm *bprm, struct elfhdr *exec,
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unsigned long load_addr, unsigned long interp_load_addr)
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{
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unsigned long p = bprm->p;
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int argc = bprm->argc;
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int envc = bprm->envc;
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elf_addr_t __user *argv;
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elf_addr_t __user *envp;
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elf_addr_t __user *sp;
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elf_addr_t __user *u_platform;
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elf_addr_t __user *u_base_platform;
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elf_addr_t __user *u_rand_bytes;
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const char *k_platform = ELF_PLATFORM;
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const char *k_base_platform = ELF_BASE_PLATFORM;
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unsigned char k_rand_bytes[16];
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int items;
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elf_addr_t *elf_info;
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int ei_index = 0;
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const struct cred *cred = current_cred();
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struct vm_area_struct *vma;
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/*
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* In some cases (e.g. Hyper-Threading), we want to avoid L1
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* evictions by the processes running on the same package. One
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* thing we can do is to shuffle the initial stack for them.
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*/
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p = arch_align_stack(p);
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/*
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* If this architecture has a platform capability string, copy it
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* to userspace. In some cases (Sparc), this info is impossible
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* for userspace to get any other way, in others (i386) it is
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* merely difficult.
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*/
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u_platform = NULL;
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if (k_platform) {
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size_t len = strlen(k_platform) + 1;
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u_platform = (elf_addr_t __user *)STACK_ALLOC(p, len);
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if (__copy_to_user(u_platform, k_platform, len))
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return -EFAULT;
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}
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/*
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* If this architecture has a "base" platform capability
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* string, copy it to userspace.
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*/
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u_base_platform = NULL;
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if (k_base_platform) {
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size_t len = strlen(k_base_platform) + 1;
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u_base_platform = (elf_addr_t __user *)STACK_ALLOC(p, len);
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if (__copy_to_user(u_base_platform, k_base_platform, len))
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return -EFAULT;
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}
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/*
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* Generate 16 random bytes for userspace PRNG seeding.
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*/
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get_random_bytes(k_rand_bytes, sizeof(k_rand_bytes));
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u_rand_bytes = (elf_addr_t __user *)
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STACK_ALLOC(p, sizeof(k_rand_bytes));
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if (__copy_to_user(u_rand_bytes, k_rand_bytes, sizeof(k_rand_bytes)))
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return -EFAULT;
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/* Create the ELF interpreter info */
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elf_info = (elf_addr_t *)current->mm->saved_auxv;
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/* update AT_VECTOR_SIZE_BASE if the number of NEW_AUX_ENT() changes */
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#define NEW_AUX_ENT(id, val) \
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do { \
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elf_info[ei_index++] = id; \
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elf_info[ei_index++] = val; \
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} while (0)
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#ifdef ARCH_DLINFO
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/*
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* ARCH_DLINFO must come first so PPC can do its special alignment of
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* AUXV.
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* update AT_VECTOR_SIZE_ARCH if the number of NEW_AUX_ENT() in
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* ARCH_DLINFO changes
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*/
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ARCH_DLINFO;
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#endif
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NEW_AUX_ENT(AT_HWCAP, ELF_HWCAP);
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NEW_AUX_ENT(AT_PAGESZ, ELF_EXEC_PAGESIZE);
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NEW_AUX_ENT(AT_CLKTCK, CLOCKS_PER_SEC);
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NEW_AUX_ENT(AT_PHDR, load_addr + exec->e_phoff);
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NEW_AUX_ENT(AT_PHENT, sizeof(struct elf_phdr));
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NEW_AUX_ENT(AT_PHNUM, exec->e_phnum);
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NEW_AUX_ENT(AT_BASE, interp_load_addr);
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NEW_AUX_ENT(AT_FLAGS, 0);
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NEW_AUX_ENT(AT_ENTRY, exec->e_entry);
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NEW_AUX_ENT(AT_UID, cred->uid);
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NEW_AUX_ENT(AT_EUID, cred->euid);
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NEW_AUX_ENT(AT_GID, cred->gid);
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NEW_AUX_ENT(AT_EGID, cred->egid);
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NEW_AUX_ENT(AT_SECURE, security_bprm_secureexec(bprm));
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NEW_AUX_ENT(AT_RANDOM, (elf_addr_t)(unsigned long)u_rand_bytes);
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NEW_AUX_ENT(AT_EXECFN, bprm->exec);
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if (k_platform) {
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NEW_AUX_ENT(AT_PLATFORM,
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(elf_addr_t)(unsigned long)u_platform);
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}
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if (k_base_platform) {
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NEW_AUX_ENT(AT_BASE_PLATFORM,
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(elf_addr_t)(unsigned long)u_base_platform);
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}
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if (bprm->interp_flags & BINPRM_FLAGS_EXECFD) {
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NEW_AUX_ENT(AT_EXECFD, bprm->interp_data);
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}
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#undef NEW_AUX_ENT
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/* AT_NULL is zero; clear the rest too */
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memset(&elf_info[ei_index], 0,
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sizeof current->mm->saved_auxv - ei_index * sizeof elf_info[0]);
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/* And advance past the AT_NULL entry. */
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ei_index += 2;
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sp = STACK_ADD(p, ei_index);
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items = (argc + 1) + (envc + 1) + 1;
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bprm->p = STACK_ROUND(sp, items);
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/* Point sp at the lowest address on the stack */
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#ifdef CONFIG_STACK_GROWSUP
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sp = (elf_addr_t __user *)bprm->p - items - ei_index;
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bprm->exec = (unsigned long)sp; /* XXX: PARISC HACK */
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#else
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sp = (elf_addr_t __user *)bprm->p;
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#endif
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/*
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* Grow the stack manually; some architectures have a limit on how
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* far ahead a user-space access may be in order to grow the stack.
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*/
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vma = find_extend_vma(current->mm, bprm->p);
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if (!vma)
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return -EFAULT;
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/* Now, let's put argc (and argv, envp if appropriate) on the stack */
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if (__put_user(argc, sp++))
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return -EFAULT;
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argv = sp;
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envp = argv + argc + 1;
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/* Populate argv and envp */
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p = current->mm->arg_end = current->mm->arg_start;
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while (argc-- > 0) {
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size_t len;
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if (__put_user((elf_addr_t)p, argv++))
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return -EFAULT;
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len = strnlen_user((void __user *)p, MAX_ARG_STRLEN);
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if (!len || len > MAX_ARG_STRLEN)
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return -EINVAL;
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p += len;
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}
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if (__put_user(0, argv))
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return -EFAULT;
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current->mm->arg_end = current->mm->env_start = p;
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while (envc-- > 0) {
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size_t len;
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if (__put_user((elf_addr_t)p, envp++))
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return -EFAULT;
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len = strnlen_user((void __user *)p, MAX_ARG_STRLEN);
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if (!len || len > MAX_ARG_STRLEN)
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return -EINVAL;
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p += len;
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}
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if (__put_user(0, envp))
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return -EFAULT;
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current->mm->env_end = p;
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/* Put the elf_info on the stack in the right place. */
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sp = (elf_addr_t __user *)envp + 1;
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if (copy_to_user(sp, elf_info, ei_index * sizeof(elf_addr_t)))
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return -EFAULT;
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return 0;
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}
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static unsigned long elf_map(struct file *filep, unsigned long addr,
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struct elf_phdr *eppnt, int prot, int type,
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unsigned long total_size)
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{
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unsigned long map_addr;
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unsigned long size = eppnt->p_filesz + ELF_PAGEOFFSET(eppnt->p_vaddr);
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unsigned long off = eppnt->p_offset - ELF_PAGEOFFSET(eppnt->p_vaddr);
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addr = ELF_PAGESTART(addr);
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size = ELF_PAGEALIGN(size);
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/* mmap() will return -EINVAL if given a zero size, but a
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* segment with zero filesize is perfectly valid */
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if (!size)
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return addr;
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down_write(¤t->mm->mmap_sem);
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/*
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* total_size is the size of the ELF (interpreter) image.
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* The _first_ mmap needs to know the full size, otherwise
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* randomization might put this image into an overlapping
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* position with the ELF binary image. (since size < total_size)
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* So we first map the 'big' image - and unmap the remainder at
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* the end. (which unmap is needed for ELF images with holes.)
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*/
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if (total_size) {
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total_size = ELF_PAGEALIGN(total_size);
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map_addr = do_mmap(filep, addr, total_size, prot, type, off);
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if (!BAD_ADDR(map_addr))
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do_munmap(current->mm, map_addr+size, total_size-size);
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} else
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map_addr = do_mmap(filep, addr, size, prot, type, off);
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up_write(¤t->mm->mmap_sem);
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return(map_addr);
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}
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static unsigned long total_mapping_size(struct elf_phdr *cmds, int nr)
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{
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int i, first_idx = -1, last_idx = -1;
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|
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for (i = 0; i < nr; i++) {
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if (cmds[i].p_type == PT_LOAD) {
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last_idx = i;
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if (first_idx == -1)
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first_idx = i;
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}
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}
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if (first_idx == -1)
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return 0;
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return cmds[last_idx].p_vaddr + cmds[last_idx].p_memsz -
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ELF_PAGESTART(cmds[first_idx].p_vaddr);
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}
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|
|
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/* This is much more generalized than the library routine read function,
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so we keep this separate. Technically the library read function
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is only provided so that we can read a.out libraries that have
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an ELF header */
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static unsigned long load_elf_interp(struct elfhdr *interp_elf_ex,
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struct file *interpreter, unsigned long *interp_map_addr,
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unsigned long no_base)
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{
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struct elf_phdr *elf_phdata;
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struct elf_phdr *eppnt;
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unsigned long load_addr = 0;
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int load_addr_set = 0;
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unsigned long last_bss = 0, elf_bss = 0;
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unsigned long error = ~0UL;
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unsigned long total_size;
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int retval, i, size;
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|
|
|
/* First of all, some simple consistency checks */
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if (interp_elf_ex->e_type != ET_EXEC &&
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interp_elf_ex->e_type != ET_DYN)
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goto out;
|
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if (!elf_check_arch(interp_elf_ex))
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goto out;
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if (!interpreter->f_op || !interpreter->f_op->mmap)
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goto out;
|
|
|
|
/*
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|
* If the size of this structure has changed, then punt, since
|
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* we will be doing the wrong thing.
|
|
*/
|
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if (interp_elf_ex->e_phentsize != sizeof(struct elf_phdr))
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goto out;
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|
if (interp_elf_ex->e_phnum < 1 ||
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interp_elf_ex->e_phnum > 65536U / sizeof(struct elf_phdr))
|
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goto out;
|
|
|
|
/* Now read in all of the header information */
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|
size = sizeof(struct elf_phdr) * interp_elf_ex->e_phnum;
|
|
if (size > ELF_MIN_ALIGN)
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goto out;
|
|
elf_phdata = kmalloc(size, GFP_KERNEL);
|
|
if (!elf_phdata)
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goto out;
|
|
|
|
retval = kernel_read(interpreter, interp_elf_ex->e_phoff,
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(char *)elf_phdata, size);
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error = -EIO;
|
|
if (retval != size) {
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if (retval < 0)
|
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error = retval;
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|
goto out_close;
|
|
}
|
|
|
|
total_size = total_mapping_size(elf_phdata, interp_elf_ex->e_phnum);
|
|
if (!total_size) {
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|
error = -EINVAL;
|
|
goto out_close;
|
|
}
|
|
|
|
eppnt = elf_phdata;
|
|
for (i = 0; i < interp_elf_ex->e_phnum; i++, eppnt++) {
|
|
if (eppnt->p_type == PT_LOAD) {
|
|
int elf_type = MAP_PRIVATE | MAP_DENYWRITE;
|
|
int elf_prot = 0;
|
|
unsigned long vaddr = 0;
|
|
unsigned long k, map_addr;
|
|
|
|
if (eppnt->p_flags & PF_R)
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|
elf_prot = PROT_READ;
|
|
if (eppnt->p_flags & PF_W)
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elf_prot |= PROT_WRITE;
|
|
if (eppnt->p_flags & PF_X)
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|
elf_prot |= PROT_EXEC;
|
|
vaddr = eppnt->p_vaddr;
|
|
if (interp_elf_ex->e_type == ET_EXEC || load_addr_set)
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|
elf_type |= MAP_FIXED;
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|
else if (no_base && interp_elf_ex->e_type == ET_DYN)
|
|
load_addr = -vaddr;
|
|
|
|
map_addr = elf_map(interpreter, load_addr + vaddr,
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|
eppnt, elf_prot, elf_type, total_size);
|
|
total_size = 0;
|
|
if (!*interp_map_addr)
|
|
*interp_map_addr = map_addr;
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|
error = map_addr;
|
|
if (BAD_ADDR(map_addr))
|
|
goto out_close;
|
|
|
|
if (!load_addr_set &&
|
|
interp_elf_ex->e_type == ET_DYN) {
|
|
load_addr = map_addr - ELF_PAGESTART(vaddr);
|
|
load_addr_set = 1;
|
|
}
|
|
|
|
/*
|
|
* Check to see if the section's size will overflow the
|
|
* allowed task size. Note that p_filesz must always be
|
|
* <= p_memsize so it'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_close;
|
|
}
|
|
|
|
/*
|
|
* Find the end of the file mapping for this phdr, and
|
|
* keep track of the largest address we see for this.
|
|
*/
|
|
k = load_addr + eppnt->p_vaddr + eppnt->p_filesz;
|
|
if (k > elf_bss)
|
|
elf_bss = k;
|
|
|
|
/*
|
|
* Do the same thing for the memory mapping - between
|
|
* elf_bss and last_bss is the bss section.
|
|
*/
|
|
k = load_addr + eppnt->p_memsz + eppnt->p_vaddr;
|
|
if (k > last_bss)
|
|
last_bss = k;
|
|
}
|
|
}
|
|
|
|
if (last_bss > elf_bss) {
|
|
/*
|
|
* Now fill out the bss section. First pad the last page up
|
|
* to the page boundary, and then perform a mmap to make sure
|
|
* that there are zero-mapped pages up to and including the
|
|
* last bss page.
|
|
*/
|
|
if (padzero(elf_bss)) {
|
|
error = -EFAULT;
|
|
goto out_close;
|
|
}
|
|
|
|
/* What we have mapped so far */
|
|
elf_bss = ELF_PAGESTART(elf_bss + ELF_MIN_ALIGN - 1);
|
|
|
|
/* Map the last of the bss segment */
|
|
down_write(¤t->mm->mmap_sem);
|
|
error = do_brk(elf_bss, last_bss - elf_bss);
|
|
up_write(¤t->mm->mmap_sem);
|
|
if (BAD_ADDR(error))
|
|
goto out_close;
|
|
}
|
|
|
|
error = load_addr;
|
|
|
|
out_close:
|
|
kfree(elf_phdata);
|
|
out:
|
|
return error;
|
|
}
|
|
|
|
/*
|
|
* These are the functions used to load ELF style executables and shared
|
|
* libraries. There is no binary dependent code anywhere else.
|
|
*/
|
|
|
|
#define INTERPRETER_NONE 0
|
|
#define INTERPRETER_ELF 2
|
|
|
|
#ifndef STACK_RND_MASK
|
|
#define STACK_RND_MASK (0x7ff >> (PAGE_SHIFT - 12)) /* 8MB of VA */
|
|
#endif
|
|
|
|
static unsigned long randomize_stack_top(unsigned long stack_top)
|
|
{
|
|
unsigned int random_variable = 0;
|
|
|
|
if ((current->flags & PF_RANDOMIZE) &&
|
|
!(current->personality & ADDR_NO_RANDOMIZE)) {
|
|
random_variable = get_random_int() & STACK_RND_MASK;
|
|
random_variable <<= PAGE_SHIFT;
|
|
}
|
|
#ifdef CONFIG_STACK_GROWSUP
|
|
return PAGE_ALIGN(stack_top) + random_variable;
|
|
#else
|
|
return PAGE_ALIGN(stack_top) - random_variable;
|
|
#endif
|
|
}
|
|
|
|
static int load_elf_binary(struct linux_binprm *bprm, struct pt_regs *regs)
|
|
{
|
|
struct file *interpreter = NULL; /* to shut gcc up */
|
|
unsigned long load_addr = 0, load_bias = 0;
|
|
int load_addr_set = 0;
|
|
char * elf_interpreter = NULL;
|
|
unsigned long error;
|
|
struct elf_phdr *elf_ppnt, *elf_phdata;
|
|
unsigned long elf_bss, elf_brk;
|
|
int retval, i;
|
|
unsigned int size;
|
|
unsigned long elf_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;
|
|
unsigned long def_flags = 0;
|
|
struct {
|
|
struct elfhdr elf_ex;
|
|
struct elfhdr interp_elf_ex;
|
|
} *loc;
|
|
|
|
loc = kmalloc(sizeof(*loc), GFP_KERNEL);
|
|
if (!loc) {
|
|
retval = -ENOMEM;
|
|
goto out_ret;
|
|
}
|
|
|
|
/* Get the exec-header */
|
|
loc->elf_ex = *((struct elfhdr *)bprm->buf);
|
|
|
|
retval = -ENOEXEC;
|
|
/* First of all, some simple consistency checks */
|
|
if (memcmp(loc->elf_ex.e_ident, ELFMAG, SELFMAG) != 0)
|
|
goto out;
|
|
|
|
if (loc->elf_ex.e_type != ET_EXEC && loc->elf_ex.e_type != ET_DYN)
|
|
goto out;
|
|
if (!elf_check_arch(&loc->elf_ex))
|
|
goto out;
|
|
if (!bprm->file->f_op || !bprm->file->f_op->mmap)
|
|
goto out;
|
|
|
|
/* Now read in all of the header information */
|
|
if (loc->elf_ex.e_phentsize != sizeof(struct elf_phdr))
|
|
goto out;
|
|
if (loc->elf_ex.e_phnum < 1 ||
|
|
loc->elf_ex.e_phnum > 65536U / sizeof(struct elf_phdr))
|
|
goto out;
|
|
size = loc->elf_ex.e_phnum * sizeof(struct elf_phdr);
|
|
retval = -ENOMEM;
|
|
elf_phdata = kmalloc(size, GFP_KERNEL);
|
|
if (!elf_phdata)
|
|
goto out;
|
|
|
|
retval = kernel_read(bprm->file, loc->elf_ex.e_phoff,
|
|
(char *)elf_phdata, size);
|
|
if (retval != size) {
|
|
if (retval >= 0)
|
|
retval = -EIO;
|
|
goto out_free_ph;
|
|
}
|
|
|
|
elf_ppnt = elf_phdata;
|
|
elf_bss = 0;
|
|
elf_brk = 0;
|
|
|
|
start_code = ~0UL;
|
|
end_code = 0;
|
|
start_data = 0;
|
|
end_data = 0;
|
|
|
|
for (i = 0; i < loc->elf_ex.e_phnum; i++) {
|
|
if (elf_ppnt->p_type == PT_INTERP) {
|
|
/* This is the program interpreter used for
|
|
* shared libraries - for now assume that this
|
|
* is an a.out format binary
|
|
*/
|
|
retval = -ENOEXEC;
|
|
if (elf_ppnt->p_filesz > PATH_MAX ||
|
|
elf_ppnt->p_filesz < 2)
|
|
goto out_free_ph;
|
|
|
|
retval = -ENOMEM;
|
|
elf_interpreter = kmalloc(elf_ppnt->p_filesz,
|
|
GFP_KERNEL);
|
|
if (!elf_interpreter)
|
|
goto out_free_ph;
|
|
|
|
retval = kernel_read(bprm->file, elf_ppnt->p_offset,
|
|
elf_interpreter,
|
|
elf_ppnt->p_filesz);
|
|
if (retval != elf_ppnt->p_filesz) {
|
|
if (retval >= 0)
|
|
retval = -EIO;
|
|
goto out_free_interp;
|
|
}
|
|
/* make sure path is NULL terminated */
|
|
retval = -ENOEXEC;
|
|
if (elf_interpreter[elf_ppnt->p_filesz - 1] != '\0')
|
|
goto out_free_interp;
|
|
|
|
interpreter = open_exec(elf_interpreter);
|
|
retval = PTR_ERR(interpreter);
|
|
if (IS_ERR(interpreter))
|
|
goto out_free_interp;
|
|
|
|
/*
|
|
* If the binary is not readable then enforce
|
|
* mm->dumpable = 0 regardless of the interpreter's
|
|
* permissions.
|
|
*/
|
|
would_dump(bprm, interpreter);
|
|
|
|
retval = kernel_read(interpreter, 0, bprm->buf,
|
|
BINPRM_BUF_SIZE);
|
|
if (retval != BINPRM_BUF_SIZE) {
|
|
if (retval >= 0)
|
|
retval = -EIO;
|
|
goto out_free_dentry;
|
|
}
|
|
|
|
/* Get the exec headers */
|
|
loc->interp_elf_ex = *((struct elfhdr *)bprm->buf);
|
|
break;
|
|
}
|
|
elf_ppnt++;
|
|
}
|
|
|
|
elf_ppnt = elf_phdata;
|
|
for (i = 0; i < loc->elf_ex.e_phnum; i++, elf_ppnt++)
|
|
if (elf_ppnt->p_type == PT_GNU_STACK) {
|
|
if (elf_ppnt->p_flags & PF_X)
|
|
executable_stack = EXSTACK_ENABLE_X;
|
|
else
|
|
executable_stack = EXSTACK_DISABLE_X;
|
|
break;
|
|
}
|
|
|
|
/* Some simple consistency checks for the interpreter */
|
|
if (elf_interpreter) {
|
|
retval = -ELIBBAD;
|
|
/* Not an ELF interpreter */
|
|
if (memcmp(loc->interp_elf_ex.e_ident, ELFMAG, SELFMAG) != 0)
|
|
goto out_free_dentry;
|
|
/* Verify the interpreter has a valid arch */
|
|
if (!elf_check_arch(&loc->interp_elf_ex))
|
|
goto out_free_dentry;
|
|
}
|
|
|
|
/* Flush all traces of the currently running executable */
|
|
retval = flush_old_exec(bprm);
|
|
if (retval)
|
|
goto out_free_dentry;
|
|
|
|
/* OK, This is the point of no return */
|
|
current->flags &= ~PF_FORKNOEXEC;
|
|
current->mm->def_flags = def_flags;
|
|
|
|
/* Do this immediately, since STACK_TOP as used in setup_arg_pages
|
|
may depend on the personality. */
|
|
SET_PERSONALITY(loc->elf_ex);
|
|
if (elf_read_implies_exec(loc->elf_ex, executable_stack))
|
|
current->personality |= READ_IMPLIES_EXEC;
|
|
|
|
if (!(current->personality & ADDR_NO_RANDOMIZE) && randomize_va_space)
|
|
current->flags |= PF_RANDOMIZE;
|
|
|
|
setup_new_exec(bprm);
|
|
|
|
/* Do this so that we can load the interpreter, if need be. We will
|
|
change some of these later */
|
|
current->mm->free_area_cache = current->mm->mmap_base;
|
|
current->mm->cached_hole_size = 0;
|
|
retval = setup_arg_pages(bprm, randomize_stack_top(STACK_TOP),
|
|
executable_stack);
|
|
if (retval < 0) {
|
|
send_sig(SIGKILL, current, 0);
|
|
goto out_free_dentry;
|
|
}
|
|
|
|
current->mm->start_stack = bprm->p;
|
|
|
|
/* 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 < loc->elf_ex.e_phnum; i++, elf_ppnt++) {
|
|
int elf_prot = 0, elf_flags;
|
|
unsigned long k, vaddr;
|
|
|
|
if (elf_ppnt->p_type != PT_LOAD)
|
|
continue;
|
|
|
|
if (unlikely (elf_brk > elf_bss)) {
|
|
unsigned long nbyte;
|
|
|
|
/* There was a PT_LOAD segment with p_memsz > p_filesz
|
|
before this one. Map anonymous pages, if needed,
|
|
and clear the area. */
|
|
retval = set_brk(elf_bss + load_bias,
|
|
elf_brk + load_bias);
|
|
if (retval) {
|
|
send_sig(SIGKILL, current, 0);
|
|
goto out_free_dentry;
|
|
}
|
|
nbyte = ELF_PAGEOFFSET(elf_bss);
|
|
if (nbyte) {
|
|
nbyte = ELF_MIN_ALIGN - nbyte;
|
|
if (nbyte > elf_brk - elf_bss)
|
|
nbyte = elf_brk - elf_bss;
|
|
if (clear_user((void __user *)elf_bss +
|
|
load_bias, nbyte)) {
|
|
/*
|
|
* This bss-zeroing can fail if the ELF
|
|
* file specifies odd protections. So
|
|
* we don't check the return value
|
|
*/
|
|
}
|
|
}
|
|
}
|
|
|
|
if (elf_ppnt->p_flags & PF_R)
|
|
elf_prot |= PROT_READ;
|
|
if (elf_ppnt->p_flags & PF_W)
|
|
elf_prot |= PROT_WRITE;
|
|
if (elf_ppnt->p_flags & PF_X)
|
|
elf_prot |= PROT_EXEC;
|
|
|
|
elf_flags = MAP_PRIVATE | MAP_DENYWRITE | MAP_EXECUTABLE;
|
|
|
|
vaddr = elf_ppnt->p_vaddr;
|
|
if (loc->elf_ex.e_type == ET_EXEC || load_addr_set) {
|
|
elf_flags |= MAP_FIXED;
|
|
} else if (loc->elf_ex.e_type == ET_DYN) {
|
|
/* Try and get dynamic programs out of the way of the
|
|
* default mmap base, as well as whatever program they
|
|
* might try to exec. This is because the brk will
|
|
* follow the loader, and is not movable. */
|
|
#if defined(CONFIG_X86) || defined(CONFIG_ARM)
|
|
load_bias = 0;
|
|
#else
|
|
load_bias = ELF_PAGESTART(ELF_ET_DYN_BASE - vaddr);
|
|
#endif
|
|
}
|
|
|
|
error = elf_map(bprm->file, load_bias + vaddr, elf_ppnt,
|
|
elf_prot, elf_flags, 0);
|
|
if (BAD_ADDR(error)) {
|
|
send_sig(SIGKILL, current, 0);
|
|
retval = IS_ERR((void *)error) ?
|
|
PTR_ERR((void*)error) : -EINVAL;
|
|
goto out_free_dentry;
|
|
}
|
|
|
|
if (!load_addr_set) {
|
|
load_addr_set = 1;
|
|
load_addr = (elf_ppnt->p_vaddr - elf_ppnt->p_offset);
|
|
if (loc->elf_ex.e_type == ET_DYN) {
|
|
load_bias += error -
|
|
ELF_PAGESTART(load_bias + vaddr);
|
|
load_addr += load_bias;
|
|
reloc_func_desc = load_bias;
|
|
}
|
|
}
|
|
k = elf_ppnt->p_vaddr;
|
|
if (k < start_code)
|
|
start_code = k;
|
|
if (start_data < k)
|
|
start_data = k;
|
|
|
|
/*
|
|
* Check to see if the section's size will overflow the
|
|
* allowed task size. Note that p_filesz must always be
|
|
* <= p_memsz so it is only necessary to check p_memsz.
|
|
*/
|
|
if (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. */
|
|
send_sig(SIGKILL, current, 0);
|
|
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)
|
|
elf_brk = k;
|
|
}
|
|
|
|
loc->elf_ex.e_entry += load_bias;
|
|
elf_bss += load_bias;
|
|
elf_brk += load_bias;
|
|
start_code += load_bias;
|
|
end_code += load_bias;
|
|
start_data += load_bias;
|
|
end_data += load_bias;
|
|
|
|
/* Calling set_brk effectively mmaps the pages that we need
|
|
* for the bss and break sections. We must do this before
|
|
* mapping in the interpreter, to make sure it doesn't wind
|
|
* up getting placed where the bss needs to go.
|
|
*/
|
|
retval = set_brk(elf_bss, elf_brk);
|
|
if (retval) {
|
|
send_sig(SIGKILL, current, 0);
|
|
goto out_free_dentry;
|
|
}
|
|
if (likely(elf_bss != elf_brk) && unlikely(padzero(elf_bss))) {
|
|
send_sig(SIGSEGV, current, 0);
|
|
retval = -EFAULT; /* Nobody gets to see this, but.. */
|
|
goto out_free_dentry;
|
|
}
|
|
|
|
if (elf_interpreter) {
|
|
unsigned long uninitialized_var(interp_map_addr);
|
|
|
|
elf_entry = load_elf_interp(&loc->interp_elf_ex,
|
|
interpreter,
|
|
&interp_map_addr,
|
|
load_bias);
|
|
if (!IS_ERR((void *)elf_entry)) {
|
|
/*
|
|
* load_elf_interp() returns relocation
|
|
* adjustment
|
|
*/
|
|
interp_load_addr = elf_entry;
|
|
elf_entry += loc->interp_elf_ex.e_entry;
|
|
}
|
|
if (BAD_ADDR(elf_entry)) {
|
|
force_sig(SIGSEGV, current);
|
|
retval = IS_ERR((void *)elf_entry) ?
|
|
(int)elf_entry : -EINVAL;
|
|
goto out_free_dentry;
|
|
}
|
|
reloc_func_desc = interp_load_addr;
|
|
|
|
allow_write_access(interpreter);
|
|
fput(interpreter);
|
|
kfree(elf_interpreter);
|
|
} else {
|
|
elf_entry = loc->elf_ex.e_entry;
|
|
if (BAD_ADDR(elf_entry)) {
|
|
force_sig(SIGSEGV, current);
|
|
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_interpreter);
|
|
if (retval < 0) {
|
|
send_sig(SIGKILL, current, 0);
|
|
goto out;
|
|
}
|
|
#endif /* ARCH_HAS_SETUP_ADDITIONAL_PAGES */
|
|
|
|
install_exec_creds(bprm);
|
|
current->flags &= ~PF_FORKNOEXEC;
|
|
retval = create_elf_tables(bprm, &loc->elf_ex,
|
|
load_addr, interp_load_addr);
|
|
if (retval < 0) {
|
|
send_sig(SIGKILL, current, 0);
|
|
goto out;
|
|
}
|
|
/* N.B. passed_fileno might not be initialized? */
|
|
current->mm->end_code = end_code;
|
|
current->mm->start_code = start_code;
|
|
current->mm->start_data = start_data;
|
|
current->mm->end_data = end_data;
|
|
current->mm->start_stack = bprm->p;
|
|
|
|
#ifdef arch_randomize_brk
|
|
if ((current->flags & PF_RANDOMIZE) && (randomize_va_space > 1)) {
|
|
current->mm->brk = current->mm->start_brk =
|
|
arch_randomize_brk(current->mm);
|
|
#ifdef CONFIG_COMPAT_BRK
|
|
current->brk_randomized = 1;
|
|
#endif
|
|
}
|
|
#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. */
|
|
down_write(¤t->mm->mmap_sem);
|
|
error = do_mmap(NULL, 0, PAGE_SIZE, PROT_READ | PROT_EXEC,
|
|
MAP_FIXED | MAP_PRIVATE, 0);
|
|
up_write(¤t->mm->mmap_sem);
|
|
}
|
|
|
|
#ifdef ELF_PLAT_INIT
|
|
/*
|
|
* The ABI may specify that certain registers be set up in special
|
|
* ways (on i386 %edx is the address of a DT_FINI function, for
|
|
* example. In addition, it may also specify (eg, PowerPC64 ELF)
|
|
* that the e_entry field is the address of the function descriptor
|
|
* for the startup routine, rather than the address of the startup
|
|
* routine itself. This macro performs whatever initialization to
|
|
* the regs structure is required as well as any relocations to the
|
|
* function descriptor entries when executing dynamically links apps.
|
|
*/
|
|
ELF_PLAT_INIT(regs, reloc_func_desc);
|
|
#endif
|
|
|
|
start_thread(regs, elf_entry, bprm->p);
|
|
retval = 0;
|
|
out:
|
|
kfree(loc);
|
|
out_ret:
|
|
return retval;
|
|
|
|
/* error cleanup */
|
|
out_free_dentry:
|
|
allow_write_access(interpreter);
|
|
if (interpreter)
|
|
fput(interpreter);
|
|
out_free_interp:
|
|
kfree(elf_interpreter);
|
|
out_free_ph:
|
|
kfree(elf_phdata);
|
|
goto out;
|
|
}
|
|
|
|
/* This is really simpleminded and specialized - we are loading an
|
|
a.out library that is given an ELF header. */
|
|
static int load_elf_library(struct file *file)
|
|
{
|
|
struct elf_phdr *elf_phdata;
|
|
struct elf_phdr *eppnt;
|
|
unsigned long elf_bss, bss, len;
|
|
int retval, error, i, j;
|
|
struct elfhdr elf_ex;
|
|
|
|
error = -ENOEXEC;
|
|
retval = kernel_read(file, 0, (char *)&elf_ex, sizeof(elf_ex));
|
|
if (retval != sizeof(elf_ex))
|
|
goto out;
|
|
|
|
if (memcmp(elf_ex.e_ident, ELFMAG, SELFMAG) != 0)
|
|
goto out;
|
|
|
|
/* First of all, some simple consistency checks */
|
|
if (elf_ex.e_type != ET_EXEC || elf_ex.e_phnum > 2 ||
|
|
!elf_check_arch(&elf_ex) || !file->f_op || !file->f_op->mmap)
|
|
goto out;
|
|
|
|
/* Now read in all of the header information */
|
|
|
|
j = sizeof(struct elf_phdr) * elf_ex.e_phnum;
|
|
/* j < ELF_MIN_ALIGN because elf_ex.e_phnum <= 2 */
|
|
|
|
error = -ENOMEM;
|
|
elf_phdata = kmalloc(j, GFP_KERNEL);
|
|
if (!elf_phdata)
|
|
goto out;
|
|
|
|
eppnt = elf_phdata;
|
|
error = -ENOEXEC;
|
|
retval = kernel_read(file, elf_ex.e_phoff, (char *)eppnt, j);
|
|
if (retval != j)
|
|
goto out_free_ph;
|
|
|
|
for (j = 0, i = 0; i<elf_ex.e_phnum; i++)
|
|
if ((eppnt + i)->p_type == PT_LOAD)
|
|
j++;
|
|
if (j != 1)
|
|
goto out_free_ph;
|
|
|
|
while (eppnt->p_type != PT_LOAD)
|
|
eppnt++;
|
|
|
|
/* Now use mmap to map the library into memory. */
|
|
down_write(¤t->mm->mmap_sem);
|
|
error = do_mmap(file,
|
|
ELF_PAGESTART(eppnt->p_vaddr),
|
|
(eppnt->p_filesz +
|
|
ELF_PAGEOFFSET(eppnt->p_vaddr)),
|
|
PROT_READ | PROT_WRITE | PROT_EXEC,
|
|
MAP_FIXED | MAP_PRIVATE | MAP_DENYWRITE,
|
|
(eppnt->p_offset -
|
|
ELF_PAGEOFFSET(eppnt->p_vaddr)));
|
|
up_write(¤t->mm->mmap_sem);
|
|
if (error != ELF_PAGESTART(eppnt->p_vaddr))
|
|
goto out_free_ph;
|
|
|
|
elf_bss = eppnt->p_vaddr + eppnt->p_filesz;
|
|
if (padzero(elf_bss)) {
|
|
error = -EFAULT;
|
|
goto out_free_ph;
|
|
}
|
|
|
|
len = ELF_PAGESTART(eppnt->p_filesz + eppnt->p_vaddr +
|
|
ELF_MIN_ALIGN - 1);
|
|
bss = eppnt->p_memsz + eppnt->p_vaddr;
|
|
if (bss > len) {
|
|
down_write(¤t->mm->mmap_sem);
|
|
do_brk(len, bss - len);
|
|
up_write(¤t->mm->mmap_sem);
|
|
}
|
|
error = 0;
|
|
|
|
out_free_ph:
|
|
kfree(elf_phdata);
|
|
out:
|
|
return error;
|
|
}
|
|
|
|
#ifdef CONFIG_ELF_CORE
|
|
/*
|
|
* ELF core dumper
|
|
*
|
|
* Modelled on fs/exec.c:aout_core_dump()
|
|
* Jeremy Fitzhardinge <jeremy@sw.oz.au>
|
|
*/
|
|
|
|
/*
|
|
* Decide what to dump of a segment, part, all or none.
|
|
*/
|
|
static unsigned long vma_dump_size(struct vm_area_struct *vma,
|
|
unsigned long mm_flags)
|
|
{
|
|
#define FILTER(type) (mm_flags & (1UL << MMF_DUMP_##type))
|
|
|
|
/* The vma can be set up to tell us the answer directly. */
|
|
if (vma->vm_flags & VM_ALWAYSDUMP)
|
|
goto whole;
|
|
|
|
/* Hugetlb memory check */
|
|
if (vma->vm_flags & VM_HUGETLB) {
|
|
if ((vma->vm_flags & VM_SHARED) && FILTER(HUGETLB_SHARED))
|
|
goto whole;
|
|
if (!(vma->vm_flags & VM_SHARED) && FILTER(HUGETLB_PRIVATE))
|
|
goto whole;
|
|
}
|
|
|
|
/* Do not dump I/O mapped devices or special mappings */
|
|
if (vma->vm_flags & (VM_IO | VM_RESERVED))
|
|
return 0;
|
|
|
|
/* By default, dump shared memory if mapped from an anonymous file. */
|
|
if (vma->vm_flags & VM_SHARED) {
|
|
if (vma->vm_file->f_path.dentry->d_inode->i_nlink == 0 ?
|
|
FILTER(ANON_SHARED) : FILTER(MAPPED_SHARED))
|
|
goto whole;
|
|
return 0;
|
|
}
|
|
|
|
/* Dump segments that have been written to. */
|
|
if (vma->anon_vma && FILTER(ANON_PRIVATE))
|
|
goto whole;
|
|
if (vma->vm_file == NULL)
|
|
return 0;
|
|
|
|
if (FILTER(MAPPED_PRIVATE))
|
|
goto whole;
|
|
|
|
/*
|
|
* If this looks like the beginning of a DSO or executable mapping,
|
|
* check for an ELF header. If we find one, dump the first page to
|
|
* aid in determining what was mapped here.
|
|
*/
|
|
if (FILTER(ELF_HEADERS) &&
|
|
vma->vm_pgoff == 0 && (vma->vm_flags & VM_READ)) {
|
|
u32 __user *header = (u32 __user *) vma->vm_start;
|
|
u32 word;
|
|
mm_segment_t fs = get_fs();
|
|
/*
|
|
* Doing it this way gets the constant folded by GCC.
|
|
*/
|
|
union {
|
|
u32 cmp;
|
|
char elfmag[SELFMAG];
|
|
} magic;
|
|
BUILD_BUG_ON(SELFMAG != sizeof word);
|
|
magic.elfmag[EI_MAG0] = ELFMAG0;
|
|
magic.elfmag[EI_MAG1] = ELFMAG1;
|
|
magic.elfmag[EI_MAG2] = ELFMAG2;
|
|
magic.elfmag[EI_MAG3] = ELFMAG3;
|
|
/*
|
|
* Switch to the user "segment" for get_user(),
|
|
* then put back what elf_core_dump() had in place.
|
|
*/
|
|
set_fs(USER_DS);
|
|
if (unlikely(get_user(word, header)))
|
|
word = 0;
|
|
set_fs(fs);
|
|
if (word == magic.cmp)
|
|
return PAGE_SIZE;
|
|
}
|
|
|
|
#undef FILTER
|
|
|
|
return 0;
|
|
|
|
whole:
|
|
return vma->vm_end - vma->vm_start;
|
|
}
|
|
|
|
/* An ELF note in memory */
|
|
struct memelfnote
|
|
{
|
|
const char *name;
|
|
int type;
|
|
unsigned int datasz;
|
|
void *data;
|
|
};
|
|
|
|
static int notesize(struct memelfnote *en)
|
|
{
|
|
int sz;
|
|
|
|
sz = sizeof(struct elf_note);
|
|
sz += roundup(strlen(en->name) + 1, 4);
|
|
sz += roundup(en->datasz, 4);
|
|
|
|
return sz;
|
|
}
|
|
|
|
#define DUMP_WRITE(addr, nr, foffset) \
|
|
do { if (!dump_write(file, (addr), (nr))) return 0; *foffset += (nr); } while(0)
|
|
|
|
static int alignfile(struct file *file, loff_t *foffset)
|
|
{
|
|
static const char buf[4] = { 0, };
|
|
DUMP_WRITE(buf, roundup(*foffset, 4) - *foffset, foffset);
|
|
return 1;
|
|
}
|
|
|
|
static int writenote(struct memelfnote *men, struct file *file,
|
|
loff_t *foffset)
|
|
{
|
|
struct elf_note en;
|
|
en.n_namesz = strlen(men->name) + 1;
|
|
en.n_descsz = men->datasz;
|
|
en.n_type = men->type;
|
|
|
|
DUMP_WRITE(&en, sizeof(en), foffset);
|
|
DUMP_WRITE(men->name, en.n_namesz, foffset);
|
|
if (!alignfile(file, foffset))
|
|
return 0;
|
|
DUMP_WRITE(men->data, men->datasz, foffset);
|
|
if (!alignfile(file, foffset))
|
|
return 0;
|
|
|
|
return 1;
|
|
}
|
|
#undef DUMP_WRITE
|
|
|
|
static void fill_elf_header(struct elfhdr *elf, int segs,
|
|
u16 machine, u32 flags, u8 osabi)
|
|
{
|
|
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;
|
|
|
|
return;
|
|
}
|
|
|
|
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 = 0;
|
|
return;
|
|
}
|
|
|
|
static void fill_note(struct memelfnote *note, const char *name, int type,
|
|
unsigned int sz, void *data)
|
|
{
|
|
note->name = name;
|
|
note->type = type;
|
|
note->datasz = sz;
|
|
note->data = data;
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* fill up all the fields in prstatus from the given task struct, except
|
|
* registers which need to be filled up separately.
|
|
*/
|
|
static void fill_prstatus(struct elf_prstatus *prstatus,
|
|
struct task_struct *p, long signr)
|
|
{
|
|
prstatus->pr_info.si_signo = prstatus->pr_cursig = signr;
|
|
prstatus->pr_sigpend = p->pending.signal.sig[0];
|
|
prstatus->pr_sighold = p->blocked.sig[0];
|
|
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);
|
|
cputime_to_timeval(cputime.utime, &prstatus->pr_utime);
|
|
cputime_to_timeval(cputime.stime, &prstatus->pr_stime);
|
|
} else {
|
|
cputime_to_timeval(p->utime, &prstatus->pr_utime);
|
|
cputime_to_timeval(p->stime, &prstatus->pr_stime);
|
|
}
|
|
cputime_to_timeval(p->signal->cutime, &prstatus->pr_cutime);
|
|
cputime_to_timeval(p->signal->cstime, &prstatus->pr_cstime);
|
|
}
|
|
|
|
static int fill_psinfo(struct elf_prpsinfo *psinfo, struct task_struct *p,
|
|
struct mm_struct *mm)
|
|
{
|
|
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, cred->uid);
|
|
SET_GID(psinfo->pr_gid, cred->gid);
|
|
rcu_read_unlock();
|
|
strncpy(psinfo->pr_fname, p->comm, sizeof(psinfo->pr_fname));
|
|
|
|
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);
|
|
}
|
|
|
|
#ifdef CORE_DUMP_USE_REGSET
|
|
#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[0];
|
|
};
|
|
|
|
struct elf_note_info {
|
|
struct elf_thread_core_info *thread;
|
|
struct memelfnote psinfo;
|
|
struct memelfnote auxv;
|
|
size_t size;
|
|
int thread_notes;
|
|
};
|
|
|
|
/*
|
|
* 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);
|
|
}
|
|
|
|
static int fill_thread_core_info(struct elf_thread_core_info *t,
|
|
const struct user_regset_view *view,
|
|
long signr, size_t *total)
|
|
{
|
|
unsigned int i;
|
|
|
|
/*
|
|
* 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 reset in here.
|
|
* We assume that regset 0 is NT_PRSTATUS.
|
|
*/
|
|
fill_prstatus(&t->prstatus, t->task, signr);
|
|
(void) view->regsets[0].get(t->task, &view->regsets[0],
|
|
0, sizeof(t->prstatus.pr_reg),
|
|
&t->prstatus.pr_reg, NULL);
|
|
|
|
fill_note(&t->notes[0], "CORE", NT_PRSTATUS,
|
|
sizeof(t->prstatus), &t->prstatus);
|
|
*total += 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, we leave t->notes[i]
|
|
* all zero and we'll know to skip writing it later.
|
|
*/
|
|
for (i = 1; i < view->n; ++i) {
|
|
const struct user_regset *regset = &view->regsets[i];
|
|
do_thread_regset_writeback(t->task, regset);
|
|
if (regset->core_note_type &&
|
|
(!regset->active || regset->active(t->task, regset))) {
|
|
int ret;
|
|
size_t size = regset->n * regset->size;
|
|
void *data = kmalloc(size, GFP_KERNEL);
|
|
if (unlikely(!data))
|
|
return 0;
|
|
ret = regset->get(t->task, regset,
|
|
0, size, data, NULL);
|
|
if (unlikely(ret))
|
|
kfree(data);
|
|
else {
|
|
if (regset->core_note_type != NT_PRFPREG)
|
|
fill_note(&t->notes[i], "LINUX",
|
|
regset->core_note_type,
|
|
size, data);
|
|
else {
|
|
t->prstatus.pr_fpvalid = 1;
|
|
fill_note(&t->notes[i], "CORE",
|
|
NT_PRFPREG, size, data);
|
|
}
|
|
*total += notesize(&t->notes[i]);
|
|
}
|
|
}
|
|
}
|
|
|
|
return 1;
|
|
}
|
|
|
|
static int fill_note_info(struct elfhdr *elf, int phdrs,
|
|
struct elf_note_info *info,
|
|
long signr, struct pt_regs *regs)
|
|
{
|
|
struct task_struct *dump_task = current;
|
|
const struct user_regset_view *view = task_user_regset_view(dump_task);
|
|
struct elf_thread_core_info *t;
|
|
struct elf_prpsinfo *psinfo;
|
|
struct core_thread *ct;
|
|
unsigned int i;
|
|
|
|
info->size = 0;
|
|
info->thread = NULL;
|
|
|
|
psinfo = kmalloc(sizeof(*psinfo), GFP_KERNEL);
|
|
if (psinfo == NULL)
|
|
return 0;
|
|
|
|
fill_note(&info->psinfo, "CORE", NT_PRPSINFO, sizeof(*psinfo), psinfo);
|
|
|
|
/*
|
|
* Figure out how many notes we're going to need for each thread.
|
|
*/
|
|
info->thread_notes = 0;
|
|
for (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, view->ei_osabi);
|
|
|
|
/*
|
|
* Allocate a structure for each thread.
|
|
*/
|
|
for (ct = &dump_task->mm->core_state->dumper; 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;
|
|
if (ct->task == dump_task || !info->thread) {
|
|
t->next = info->thread;
|
|
info->thread = t;
|
|
} else {
|
|
/*
|
|
* Make sure to keep the original task at
|
|
* the head of the list.
|
|
*/
|
|
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, signr, &info->size))
|
|
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_auxv_note(&info->auxv, current->mm);
|
|
info->size += notesize(&info->auxv);
|
|
|
|
return 1;
|
|
}
|
|
|
|
static size_t get_note_info_size(struct elf_note_info *info)
|
|
{
|
|
return info->size;
|
|
}
|
|
|
|
/*
|
|
* 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 file *file, loff_t *foffset)
|
|
{
|
|
bool first = 1;
|
|
struct elf_thread_core_info *t = info->thread;
|
|
|
|
do {
|
|
int i;
|
|
|
|
if (!writenote(&t->notes[0], file, foffset))
|
|
return 0;
|
|
|
|
if (first && !writenote(&info->psinfo, file, foffset))
|
|
return 0;
|
|
if (first && !writenote(&info->auxv, file, foffset))
|
|
return 0;
|
|
|
|
for (i = 1; i < info->thread_notes; ++i)
|
|
if (t->notes[i].data &&
|
|
!writenote(&t->notes[i], file, foffset))
|
|
return 0;
|
|
|
|
first = 0;
|
|
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);
|
|
}
|
|
|
|
#else
|
|
|
|
/* 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 threads pr_status and then create
|
|
* a single section for them in the final core file.
|
|
*/
|
|
static int elf_dump_thread_status(long signr, struct elf_thread_status *t)
|
|
{
|
|
int sz = 0;
|
|
struct task_struct *p = t->thread;
|
|
t->num_notes = 0;
|
|
|
|
fill_prstatus(&t->prstatus, p, signr);
|
|
elf_core_copy_task_regs(p, &t->prstatus.pr_reg);
|
|
|
|
fill_note(&t->notes[0], "CORE", NT_PRSTATUS, sizeof(t->prstatus),
|
|
&(t->prstatus));
|
|
t->num_notes++;
|
|
sz += notesize(&t->notes[0]);
|
|
|
|
if ((t->prstatus.pr_fpvalid = elf_core_copy_task_fpregs(p, NULL,
|
|
&t->fpu))) {
|
|
fill_note(&t->notes[1], "CORE", NT_PRFPREG, sizeof(t->fpu),
|
|
&(t->fpu));
|
|
t->num_notes++;
|
|
sz += notesize(&t->notes[1]);
|
|
}
|
|
|
|
#ifdef ELF_CORE_COPY_XFPREGS
|
|
if (elf_core_copy_task_xfpregs(p, &t->xfpu)) {
|
|
fill_note(&t->notes[2], "LINUX", ELF_CORE_XFPREG_TYPE,
|
|
sizeof(t->xfpu), &t->xfpu);
|
|
t->num_notes++;
|
|
sz += notesize(&t->notes[2]);
|
|
}
|
|
#endif
|
|
return sz;
|
|
}
|
|
|
|
struct elf_note_info {
|
|
struct memelfnote *notes;
|
|
struct elf_prstatus *prstatus; /* NT_PRSTATUS */
|
|
struct elf_prpsinfo *psinfo; /* NT_PRPSINFO */
|
|
struct list_head thread_list;
|
|
elf_fpregset_t *fpu;
|
|
#ifdef ELF_CORE_COPY_XFPREGS
|
|
elf_fpxregset_t *xfpu;
|
|
#endif
|
|
int thread_status_size;
|
|
int numnote;
|
|
};
|
|
|
|
static int elf_note_info_init(struct elf_note_info *info)
|
|
{
|
|
memset(info, 0, sizeof(*info));
|
|
INIT_LIST_HEAD(&info->thread_list);
|
|
|
|
/* Allocate space for six ELF notes */
|
|
info->notes = kmalloc(6 * sizeof(struct memelfnote), GFP_KERNEL);
|
|
if (!info->notes)
|
|
return 0;
|
|
info->psinfo = kmalloc(sizeof(*info->psinfo), GFP_KERNEL);
|
|
if (!info->psinfo)
|
|
goto notes_free;
|
|
info->prstatus = kmalloc(sizeof(*info->prstatus), GFP_KERNEL);
|
|
if (!info->prstatus)
|
|
goto psinfo_free;
|
|
info->fpu = kmalloc(sizeof(*info->fpu), GFP_KERNEL);
|
|
if (!info->fpu)
|
|
goto prstatus_free;
|
|
#ifdef ELF_CORE_COPY_XFPREGS
|
|
info->xfpu = kmalloc(sizeof(*info->xfpu), GFP_KERNEL);
|
|
if (!info->xfpu)
|
|
goto fpu_free;
|
|
#endif
|
|
return 1;
|
|
#ifdef ELF_CORE_COPY_XFPREGS
|
|
fpu_free:
|
|
kfree(info->fpu);
|
|
#endif
|
|
prstatus_free:
|
|
kfree(info->prstatus);
|
|
psinfo_free:
|
|
kfree(info->psinfo);
|
|
notes_free:
|
|
kfree(info->notes);
|
|
return 0;
|
|
}
|
|
|
|
static int fill_note_info(struct elfhdr *elf, int phdrs,
|
|
struct elf_note_info *info,
|
|
long signr, struct pt_regs *regs)
|
|
{
|
|
struct list_head *t;
|
|
|
|
if (!elf_note_info_init(info))
|
|
return 0;
|
|
|
|
if (signr) {
|
|
struct core_thread *ct;
|
|
struct elf_thread_status *ets;
|
|
|
|
for (ct = current->mm->core_state->dumper.next;
|
|
ct; ct = ct->next) {
|
|
ets = kzalloc(sizeof(*ets), GFP_KERNEL);
|
|
if (!ets)
|
|
return 0;
|
|
|
|
ets->thread = ct->task;
|
|
list_add(&ets->list, &info->thread_list);
|
|
}
|
|
|
|
list_for_each(t, &info->thread_list) {
|
|
int sz;
|
|
|
|
ets = list_entry(t, struct elf_thread_status, list);
|
|
sz = elf_dump_thread_status(signr, ets);
|
|
info->thread_status_size += sz;
|
|
}
|
|
}
|
|
/* now collect the dump for the current */
|
|
memset(info->prstatus, 0, sizeof(*info->prstatus));
|
|
fill_prstatus(info->prstatus, current, signr);
|
|
elf_core_copy_regs(&info->prstatus->pr_reg, regs);
|
|
|
|
/* Set up header */
|
|
fill_elf_header(elf, phdrs, ELF_ARCH, ELF_CORE_EFLAGS, ELF_OSABI);
|
|
|
|
/*
|
|
* Set up the notes in similar form to SVR4 core dumps made
|
|
* with info from their /proc.
|
|
*/
|
|
|
|
fill_note(info->notes + 0, "CORE", NT_PRSTATUS,
|
|
sizeof(*info->prstatus), info->prstatus);
|
|
fill_psinfo(info->psinfo, current->group_leader, current->mm);
|
|
fill_note(info->notes + 1, "CORE", NT_PRPSINFO,
|
|
sizeof(*info->psinfo), info->psinfo);
|
|
|
|
info->numnote = 2;
|
|
|
|
fill_auxv_note(&info->notes[info->numnote++], current->mm);
|
|
|
|
/* Try to dump the FPU. */
|
|
info->prstatus->pr_fpvalid = elf_core_copy_task_fpregs(current, regs,
|
|
info->fpu);
|
|
if (info->prstatus->pr_fpvalid)
|
|
fill_note(info->notes + info->numnote++,
|
|
"CORE", NT_PRFPREG, sizeof(*info->fpu), info->fpu);
|
|
#ifdef ELF_CORE_COPY_XFPREGS
|
|
if (elf_core_copy_task_xfpregs(current, info->xfpu))
|
|
fill_note(info->notes + info->numnote++,
|
|
"LINUX", ELF_CORE_XFPREG_TYPE,
|
|
sizeof(*info->xfpu), info->xfpu);
|
|
#endif
|
|
|
|
return 1;
|
|
}
|
|
|
|
static size_t get_note_info_size(struct elf_note_info *info)
|
|
{
|
|
int sz = 0;
|
|
int i;
|
|
|
|
for (i = 0; i < info->numnote; i++)
|
|
sz += notesize(info->notes + i);
|
|
|
|
sz += info->thread_status_size;
|
|
|
|
return sz;
|
|
}
|
|
|
|
static int write_note_info(struct elf_note_info *info,
|
|
struct file *file, loff_t *foffset)
|
|
{
|
|
int i;
|
|
struct list_head *t;
|
|
|
|
for (i = 0; i < info->numnote; i++)
|
|
if (!writenote(info->notes + i, file, foffset))
|
|
return 0;
|
|
|
|
/* write out the thread status notes section */
|
|
list_for_each(t, &info->thread_list) {
|
|
struct elf_thread_status *tmp =
|
|
list_entry(t, struct elf_thread_status, list);
|
|
|
|
for (i = 0; i < tmp->num_notes; i++)
|
|
if (!writenote(&tmp->notes[i], file, foffset))
|
|
return 0;
|
|
}
|
|
|
|
return 1;
|
|
}
|
|
|
|
static void free_note_info(struct elf_note_info *info)
|
|
{
|
|
while (!list_empty(&info->thread_list)) {
|
|
struct list_head *tmp = info->thread_list.next;
|
|
list_del(tmp);
|
|
kfree(list_entry(tmp, struct elf_thread_status, list));
|
|
}
|
|
|
|
kfree(info->prstatus);
|
|
kfree(info->psinfo);
|
|
kfree(info->notes);
|
|
kfree(info->fpu);
|
|
#ifdef ELF_CORE_COPY_XFPREGS
|
|
kfree(info->xfpu);
|
|
#endif
|
|
}
|
|
|
|
#endif
|
|
|
|
static struct vm_area_struct *first_vma(struct task_struct *tsk,
|
|
struct vm_area_struct *gate_vma)
|
|
{
|
|
struct vm_area_struct *ret = tsk->mm->mmap;
|
|
|
|
if (ret)
|
|
return ret;
|
|
return gate_vma;
|
|
}
|
|
/*
|
|
* Helper function for iterating across a vma list. It ensures that the caller
|
|
* will visit `gate_vma' prior to terminating the search.
|
|
*/
|
|
static struct vm_area_struct *next_vma(struct vm_area_struct *this_vma,
|
|
struct vm_area_struct *gate_vma)
|
|
{
|
|
struct vm_area_struct *ret;
|
|
|
|
ret = this_vma->vm_next;
|
|
if (ret)
|
|
return ret;
|
|
if (this_vma == gate_vma)
|
|
return NULL;
|
|
return gate_vma;
|
|
}
|
|
|
|
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;
|
|
}
|
|
|
|
static size_t elf_core_vma_data_size(struct vm_area_struct *gate_vma,
|
|
unsigned long mm_flags)
|
|
{
|
|
struct vm_area_struct *vma;
|
|
size_t size = 0;
|
|
|
|
for (vma = first_vma(current, gate_vma); vma != NULL;
|
|
vma = next_vma(vma, gate_vma))
|
|
size += vma_dump_size(vma, mm_flags);
|
|
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_core_dump(struct coredump_params *cprm)
|
|
{
|
|
int has_dumped = 0;
|
|
mm_segment_t fs;
|
|
int segs;
|
|
size_t size = 0;
|
|
struct vm_area_struct *vma, *gate_vma;
|
|
struct elfhdr *elf = NULL;
|
|
loff_t offset = 0, dataoff, foffset;
|
|
struct elf_note_info info;
|
|
struct elf_phdr *phdr4note = NULL;
|
|
struct elf_shdr *shdr4extnum = NULL;
|
|
Elf_Half e_phnum;
|
|
elf_addr_t e_shoff;
|
|
|
|
/*
|
|
* 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 out;
|
|
/*
|
|
* The number of segs are recored into ELF header as 16bit value.
|
|
* Please check DEFAULT_MAX_MAP_COUNT definition when you modify here.
|
|
*/
|
|
segs = current->mm->map_count;
|
|
segs += elf_core_extra_phdrs();
|
|
|
|
gate_vma = get_gate_vma(current->mm);
|
|
if (gate_vma != NULL)
|
|
segs++;
|
|
|
|
/* 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->signr, cprm->regs))
|
|
goto cleanup;
|
|
|
|
has_dumped = 1;
|
|
current->flags |= PF_DUMPCORE;
|
|
|
|
fs = get_fs();
|
|
set_fs(KERNEL_DS);
|
|
|
|
offset += sizeof(*elf); /* Elf header */
|
|
offset += segs * sizeof(struct elf_phdr); /* Program headers */
|
|
foffset = offset;
|
|
|
|
/* Write notes phdr entry */
|
|
{
|
|
size_t sz = get_note_info_size(&info);
|
|
|
|
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 += elf_core_vma_data_size(gate_vma, 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;
|
|
|
|
size += sizeof(*elf);
|
|
if (size > cprm->limit || !dump_write(cprm->file, elf, sizeof(*elf)))
|
|
goto end_coredump;
|
|
|
|
size += sizeof(*phdr4note);
|
|
if (size > cprm->limit
|
|
|| !dump_write(cprm->file, phdr4note, sizeof(*phdr4note)))
|
|
goto end_coredump;
|
|
|
|
/* Write program headers for segments dump */
|
|
for (vma = first_vma(current, gate_vma); vma != NULL;
|
|
vma = next_vma(vma, gate_vma)) {
|
|
struct elf_phdr phdr;
|
|
|
|
phdr.p_type = PT_LOAD;
|
|
phdr.p_offset = offset;
|
|
phdr.p_vaddr = vma->vm_start;
|
|
phdr.p_paddr = 0;
|
|
phdr.p_filesz = vma_dump_size(vma, cprm->mm_flags);
|
|
phdr.p_memsz = vma->vm_end - vma->vm_start;
|
|
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;
|
|
|
|
size += sizeof(phdr);
|
|
if (size > cprm->limit
|
|
|| !dump_write(cprm->file, &phdr, sizeof(phdr)))
|
|
goto end_coredump;
|
|
}
|
|
|
|
if (!elf_core_write_extra_phdrs(cprm->file, offset, &size, cprm->limit))
|
|
goto end_coredump;
|
|
|
|
/* write out the notes section */
|
|
if (!write_note_info(&info, cprm->file, &foffset))
|
|
goto end_coredump;
|
|
|
|
if (elf_coredump_extra_notes_write(cprm->file, &foffset))
|
|
goto end_coredump;
|
|
|
|
/* Align to page */
|
|
if (!dump_seek(cprm->file, dataoff - foffset))
|
|
goto end_coredump;
|
|
|
|
for (vma = first_vma(current, gate_vma); vma != NULL;
|
|
vma = next_vma(vma, gate_vma)) {
|
|
unsigned long addr;
|
|
unsigned long end;
|
|
|
|
end = vma->vm_start + vma_dump_size(vma, cprm->mm_flags);
|
|
|
|
for (addr = vma->vm_start; addr < end; addr += PAGE_SIZE) {
|
|
struct page *page;
|
|
int stop;
|
|
|
|
page = get_dump_page(addr);
|
|
if (page) {
|
|
void *kaddr = kmap(page);
|
|
stop = ((size += PAGE_SIZE) > cprm->limit) ||
|
|
!dump_write(cprm->file, kaddr,
|
|
PAGE_SIZE);
|
|
kunmap(page);
|
|
page_cache_release(page);
|
|
} else
|
|
stop = !dump_seek(cprm->file, PAGE_SIZE);
|
|
if (stop)
|
|
goto end_coredump;
|
|
}
|
|
}
|
|
|
|
if (!elf_core_write_extra_data(cprm->file, &size, cprm->limit))
|
|
goto end_coredump;
|
|
|
|
if (e_phnum == PN_XNUM) {
|
|
size += sizeof(*shdr4extnum);
|
|
if (size > cprm->limit
|
|
|| !dump_write(cprm->file, shdr4extnum,
|
|
sizeof(*shdr4extnum)))
|
|
goto end_coredump;
|
|
}
|
|
|
|
end_coredump:
|
|
set_fs(fs);
|
|
|
|
cleanup:
|
|
free_note_info(&info);
|
|
kfree(shdr4extnum);
|
|
kfree(phdr4note);
|
|
kfree(elf);
|
|
out:
|
|
return has_dumped;
|
|
}
|
|
|
|
#endif /* CONFIG_ELF_CORE */
|
|
|
|
static int __init init_elf_binfmt(void)
|
|
{
|
|
return register_binfmt(&elf_format);
|
|
}
|
|
|
|
static void __exit exit_elf_binfmt(void)
|
|
{
|
|
/* Remove the COFF and ELF loaders. */
|
|
unregister_binfmt(&elf_format);
|
|
}
|
|
|
|
core_initcall(init_elf_binfmt);
|
|
module_exit(exit_elf_binfmt);
|
|
MODULE_LICENSE("GPL");
|