[T106][ZXW-22]7520V3SCV2.01.01.02P42U09_VEC_V0.8_AP_VEC origin source commit
Change-Id: Ic6e05d89ecd62fc34f82b23dcf306c93764aec4b
diff --git a/ap/os/linux/linux-3.4.x/fs/exec.c b/ap/os/linux/linux-3.4.x/fs/exec.c
new file mode 100755
index 0000000..cde8181
--- /dev/null
+++ b/ap/os/linux/linux-3.4.x/fs/exec.c
@@ -0,0 +1,2376 @@
+/*
+ * linux/fs/exec.c
+ *
+ * Copyright (C) 1991, 1992 Linus Torvalds
+ */
+
+/*
+ * #!-checking implemented by tytso.
+ */
+/*
+ * Demand-loading implemented 01.12.91 - no need to read anything but
+ * the header into memory. The inode of the executable is put into
+ * "current->executable", and page faults do the actual loading. Clean.
+ *
+ * Once more I can proudly say that linux stood up to being changed: it
+ * was less than 2 hours work to get demand-loading completely implemented.
+ *
+ * Demand loading changed July 1993 by Eric Youngdale. Use mmap instead,
+ * current->executable is only used by the procfs. This allows a dispatch
+ * table to check for several different types of binary formats. We keep
+ * trying until we recognize the file or we run out of supported binary
+ * formats.
+ */
+
+#include <linux/slab.h>
+#include <linux/file.h>
+#include <linux/fdtable.h>
+#include <linux/mm.h>
+#include <linux/stat.h>
+#include <linux/fcntl.h>
+#include <linux/swap.h>
+#include <linux/string.h>
+#include <linux/init.h>
+#include <linux/pagemap.h>
+#include <linux/perf_event.h>
+#include <linux/highmem.h>
+#include <linux/spinlock.h>
+#include <linux/key.h>
+#include <linux/personality.h>
+#include <linux/binfmts.h>
+#include <linux/utsname.h>
+#include <linux/pid_namespace.h>
+#include <linux/module.h>
+#include <linux/namei.h>
+#include <linux/mount.h>
+#include <linux/security.h>
+#include <linux/syscalls.h>
+#include <linux/tsacct_kern.h>
+#include <linux/cn_proc.h>
+#include <linux/audit.h>
+#include <linux/tracehook.h>
+#include <linux/kmod.h>
+#include <linux/fsnotify.h>
+#include <linux/fs_struct.h>
+#include <linux/pipe_fs_i.h>
+#include <linux/oom.h>
+#include <linux/compat.h>
+
+#include <asm/uaccess.h>
+#include <asm/mmu_context.h>
+#include <asm/tlb.h>
+#include <asm/exec.h>
+
+#include <trace/events/task.h>
+#include "internal.h"
+
+#include <trace/events/sched.h>
+
+int core_uses_pid;
+char core_pattern[CORENAME_MAX_SIZE] = "core";
+unsigned int core_pipe_limit;
+int suid_dumpable = 0;
+
+struct core_name {
+ char *corename;
+ int used, size;
+};
+static atomic_t call_count = ATOMIC_INIT(1);
+
+/* The maximal length of core_pattern is also specified in sysctl.c */
+
+static LIST_HEAD(formats);
+static DEFINE_RWLOCK(binfmt_lock);
+
+void __register_binfmt(struct linux_binfmt * fmt, int insert)
+{
+ BUG_ON(!fmt);
+ write_lock(&binfmt_lock);
+ insert ? list_add(&fmt->lh, &formats) :
+ list_add_tail(&fmt->lh, &formats);
+ write_unlock(&binfmt_lock);
+}
+
+EXPORT_SYMBOL(__register_binfmt);
+
+void unregister_binfmt(struct linux_binfmt * fmt)
+{
+ write_lock(&binfmt_lock);
+ list_del(&fmt->lh);
+ write_unlock(&binfmt_lock);
+}
+
+EXPORT_SYMBOL(unregister_binfmt);
+
+static inline void put_binfmt(struct linux_binfmt * fmt)
+{
+ module_put(fmt->module);
+}
+
+/*
+ * Note that a shared library must be both readable and executable due to
+ * security reasons.
+ *
+ * Also note that we take the address to load from from the file itself.
+ */
+SYSCALL_DEFINE1(uselib, const char __user *, library)
+{
+ struct file *file;
+ char *tmp = getname(library);
+ int error = PTR_ERR(tmp);
+ static const struct open_flags uselib_flags = {
+ .open_flag = O_LARGEFILE | O_RDONLY | __FMODE_EXEC,
+ .acc_mode = MAY_READ | MAY_EXEC | MAY_OPEN,
+ .intent = LOOKUP_OPEN
+ };
+
+ if (IS_ERR(tmp))
+ goto out;
+
+ file = do_filp_open(AT_FDCWD, tmp, &uselib_flags, LOOKUP_FOLLOW);
+ putname(tmp);
+ error = PTR_ERR(file);
+ if (IS_ERR(file))
+ goto out;
+
+ error = -EINVAL;
+ if (!S_ISREG(file->f_path.dentry->d_inode->i_mode))
+ goto exit;
+
+ error = -EACCES;
+ if (file->f_path.mnt->mnt_flags & MNT_NOEXEC)
+ goto exit;
+
+ fsnotify_open(file);
+
+ error = -ENOEXEC;
+ if(file->f_op) {
+ struct linux_binfmt * fmt;
+
+ read_lock(&binfmt_lock);
+ list_for_each_entry(fmt, &formats, lh) {
+ if (!fmt->load_shlib)
+ continue;
+ if (!try_module_get(fmt->module))
+ continue;
+ read_unlock(&binfmt_lock);
+ error = fmt->load_shlib(file);
+ read_lock(&binfmt_lock);
+ put_binfmt(fmt);
+ if (error != -ENOEXEC)
+ break;
+ }
+ read_unlock(&binfmt_lock);
+ }
+exit:
+ fput(file);
+out:
+ return error;
+}
+
+#ifdef CONFIG_MMU
+/*
+ * The nascent bprm->mm is not visible until exec_mmap() but it can
+ * use a lot of memory, account these pages in current->mm temporary
+ * for oom_badness()->get_mm_rss(). Once exec succeeds or fails, we
+ * change the counter back via acct_arg_size(0).
+ */
+static void acct_arg_size(struct linux_binprm *bprm, unsigned long pages)
+{
+ struct mm_struct *mm = current->mm;
+ long diff = (long)(pages - bprm->vma_pages);
+
+ if (!mm || !diff)
+ return;
+
+ bprm->vma_pages = pages;
+ add_mm_counter(mm, MM_ANONPAGES, diff);
+}
+
+static struct page *get_arg_page(struct linux_binprm *bprm, unsigned long pos,
+ int write)
+{
+ struct page *page;
+ int ret;
+
+#ifdef CONFIG_STACK_GROWSUP
+ if (write) {
+ ret = expand_downwards(bprm->vma, pos);
+ if (ret < 0)
+ return NULL;
+ }
+#endif
+ ret = get_user_pages(current, bprm->mm, pos,
+ 1, write, 1, &page, NULL);
+ if (ret <= 0)
+ return NULL;
+
+ if (write) {
+ unsigned long size = bprm->vma->vm_end - bprm->vma->vm_start;
+ unsigned long ptr_size;
+ struct rlimit *rlim;
+ /*fix for HUB CVE-2017-1000365*/
+ /*
+ * Since the stack will hold pointers to the strings, we
+ * must account for them as well.
+ *
+ * The size calculation is the entire vma while each arg page is
+ * built, so each time we get here it's calculating how far it
+ * is currently (rather than each call being just the newly
+ * added size from the arg page). As a result, we need to
+ * always add the entire size of the pointers, so that on the
+ * last call to get_arg_page() we'll actually have the entire
+ * correct size.
+ */
+ ptr_size = (bprm->argc + bprm->envc) * sizeof(void *);
+ if (ptr_size > ULONG_MAX - size)
+ goto fail;
+ size += ptr_size;
+
+ acct_arg_size(bprm, size / PAGE_SIZE);
+
+ /*
+ * We've historically supported up to 32 pages (ARG_MAX)
+ * of argument strings even with small stacks
+ */
+ if (size <= ARG_MAX)
+ return page;
+
+ /*
+ * Limit to 1/4-th the stack size for the argv+env strings.
+ * This ensures that:
+ * - the remaining binfmt code will not run out of stack space,
+ * - the program will have a reasonable amount of stack left
+ * to work from.
+ */
+ rlim = current->signal->rlim;
+ if (size > ACCESS_ONCE(rlim[RLIMIT_STACK].rlim_cur) / 4)
+ goto fail;
+ }
+
+ return page;
+
+fail:
+ put_page(page);
+ return NULL;
+}
+
+static void put_arg_page(struct page *page)
+{
+ put_page(page);
+}
+
+static void free_arg_page(struct linux_binprm *bprm, int i)
+{
+}
+
+static void free_arg_pages(struct linux_binprm *bprm)
+{
+}
+
+static void flush_arg_page(struct linux_binprm *bprm, unsigned long pos,
+ struct page *page)
+{
+ flush_cache_page(bprm->vma, pos, page_to_pfn(page));
+}
+
+static int __bprm_mm_init(struct linux_binprm *bprm)
+{
+ int err;
+ struct vm_area_struct *vma = NULL;
+ struct mm_struct *mm = bprm->mm;
+
+ bprm->vma = vma = kmem_cache_zalloc(vm_area_cachep, GFP_KERNEL);
+ if (!vma)
+ return -ENOMEM;
+
+ down_write(&mm->mmap_sem);
+ vma->vm_mm = mm;
+
+ /*
+ * Place the stack at the largest stack address the architecture
+ * supports. Later, we'll move this to an appropriate place. We don't
+ * use STACK_TOP because that can depend on attributes which aren't
+ * configured yet.
+ */
+ BUILD_BUG_ON(VM_STACK_FLAGS & VM_STACK_INCOMPLETE_SETUP);
+ vma->vm_end = STACK_TOP_MAX;
+ vma->vm_start = vma->vm_end - PAGE_SIZE;
+ vma->vm_flags = VM_STACK_FLAGS | VM_STACK_INCOMPLETE_SETUP;
+ vma->vm_page_prot = vm_get_page_prot(vma->vm_flags);
+ INIT_LIST_HEAD(&vma->anon_vma_chain);
+
+ err = security_file_mmap(NULL, 0, 0, 0, vma->vm_start, 1);
+ if (err)
+ goto err;
+
+ err = insert_vm_struct(mm, vma);
+ if (err)
+ goto err;
+
+ mm->stack_vm = mm->total_vm = 1;
+ up_write(&mm->mmap_sem);
+ bprm->p = vma->vm_end - sizeof(void *);
+ return 0;
+err:
+ up_write(&mm->mmap_sem);
+ bprm->vma = NULL;
+ kmem_cache_free(vm_area_cachep, vma);
+ return err;
+}
+
+static bool valid_arg_len(struct linux_binprm *bprm, long len)
+{
+ return len <= MAX_ARG_STRLEN;
+}
+
+#else
+
+static inline void acct_arg_size(struct linux_binprm *bprm, unsigned long pages)
+{
+}
+
+static struct page *get_arg_page(struct linux_binprm *bprm, unsigned long pos,
+ int write)
+{
+ struct page *page;
+
+ page = bprm->page[pos / PAGE_SIZE];
+ if (!page && write) {
+ page = alloc_page(GFP_HIGHUSER|__GFP_ZERO);
+ if (!page)
+ return NULL;
+ bprm->page[pos / PAGE_SIZE] = page;
+ }
+
+ return page;
+}
+
+static void put_arg_page(struct page *page)
+{
+}
+
+static void free_arg_page(struct linux_binprm *bprm, int i)
+{
+ if (bprm->page[i]) {
+ __free_page(bprm->page[i]);
+ bprm->page[i] = NULL;
+ }
+}
+
+static void free_arg_pages(struct linux_binprm *bprm)
+{
+ int i;
+
+ for (i = 0; i < MAX_ARG_PAGES; i++)
+ free_arg_page(bprm, i);
+}
+
+static void flush_arg_page(struct linux_binprm *bprm, unsigned long pos,
+ struct page *page)
+{
+}
+
+static int __bprm_mm_init(struct linux_binprm *bprm)
+{
+ bprm->p = PAGE_SIZE * MAX_ARG_PAGES - sizeof(void *);
+ return 0;
+}
+
+static bool valid_arg_len(struct linux_binprm *bprm, long len)
+{
+ return len <= bprm->p;
+}
+
+#endif /* CONFIG_MMU */
+
+/*
+ * Create a new mm_struct and populate it with a temporary stack
+ * vm_area_struct. We don't have enough context at this point to set the stack
+ * flags, permissions, and offset, so we use temporary values. We'll update
+ * them later in setup_arg_pages().
+ */
+int bprm_mm_init(struct linux_binprm *bprm)
+{
+ int err;
+ struct mm_struct *mm = NULL;
+
+ bprm->mm = mm = mm_alloc();
+ err = -ENOMEM;
+ if (!mm)
+ goto err;
+
+ err = init_new_context(current, mm);
+ if (err)
+ goto err;
+
+ err = __bprm_mm_init(bprm);
+ if (err)
+ goto err;
+
+ return 0;
+
+err:
+ if (mm) {
+ bprm->mm = NULL;
+ mmdrop(mm);
+ }
+
+ return err;
+}
+
+struct user_arg_ptr {
+#ifdef CONFIG_COMPAT
+ bool is_compat;
+#endif
+ union {
+ const char __user *const __user *native;
+#ifdef CONFIG_COMPAT
+ compat_uptr_t __user *compat;
+#endif
+ } ptr;
+};
+
+static const char __user *get_user_arg_ptr(struct user_arg_ptr argv, int nr)
+{
+ const char __user *native;
+
+#ifdef CONFIG_COMPAT
+ if (unlikely(argv.is_compat)) {
+ compat_uptr_t compat;
+
+ if (get_user(compat, argv.ptr.compat + nr))
+ return ERR_PTR(-EFAULT);
+
+ return compat_ptr(compat);
+ }
+#endif
+
+ if (get_user(native, argv.ptr.native + nr))
+ return ERR_PTR(-EFAULT);
+
+ return native;
+}
+
+/*
+ * count() counts the number of strings in array ARGV.
+ */
+static int count(struct user_arg_ptr argv, int max)
+{
+ int i = 0;
+
+ if (argv.ptr.native != NULL) {
+ for (;;) {
+ const char __user *p = get_user_arg_ptr(argv, i);
+
+ if (!p)
+ break;
+
+ if (IS_ERR(p))
+ return -EFAULT;
+
+ if (i++ >= max)
+ return -E2BIG;
+
+ if (fatal_signal_pending(current))
+ return -ERESTARTNOHAND;
+ cond_resched();
+ }
+ }
+ return i;
+}
+
+/*
+ * 'copy_strings()' copies argument/environment strings from the old
+ * processes's memory to the new process's stack. The call to get_user_pages()
+ * ensures the destination page is created and not swapped out.
+ */
+static int copy_strings(int argc, struct user_arg_ptr argv,
+ struct linux_binprm *bprm)
+{
+ struct page *kmapped_page = NULL;
+ char *kaddr = NULL;
+ unsigned long kpos = 0;
+ int ret;
+
+ while (argc-- > 0) {
+ const char __user *str;
+ int len;
+ unsigned long pos;
+
+ ret = -EFAULT;
+ str = get_user_arg_ptr(argv, argc);
+ if (IS_ERR(str))
+ goto out;
+
+ len = strnlen_user(str, MAX_ARG_STRLEN);
+ if (!len)
+ goto out;
+
+ ret = -E2BIG;
+ if (!valid_arg_len(bprm, len))
+ goto out;
+
+ /* We're going to work our way backwords. */
+ pos = bprm->p;
+ str += len;
+ bprm->p -= len;
+
+ while (len > 0) {
+ int offset, bytes_to_copy;
+
+ if (fatal_signal_pending(current)) {
+ ret = -ERESTARTNOHAND;
+ goto out;
+ }
+ cond_resched();
+
+ offset = pos % PAGE_SIZE;
+ if (offset == 0)
+ offset = PAGE_SIZE;
+
+ bytes_to_copy = offset;
+ if (bytes_to_copy > len)
+ bytes_to_copy = len;
+
+ offset -= bytes_to_copy;
+ pos -= bytes_to_copy;
+ str -= bytes_to_copy;
+ len -= bytes_to_copy;
+
+ if (!kmapped_page || kpos != (pos & PAGE_MASK)) {
+ struct page *page;
+
+ page = get_arg_page(bprm, pos, 1);
+ if (!page) {
+ ret = -E2BIG;
+ goto out;
+ }
+
+ if (kmapped_page) {
+ flush_kernel_dcache_page(kmapped_page);
+ kunmap(kmapped_page);
+ put_arg_page(kmapped_page);
+ }
+ kmapped_page = page;
+ kaddr = kmap(kmapped_page);
+ kpos = pos & PAGE_MASK;
+ flush_arg_page(bprm, kpos, kmapped_page);
+ }
+ if (copy_from_user(kaddr+offset, str, bytes_to_copy)) {
+ ret = -EFAULT;
+ goto out;
+ }
+ }
+ }
+ ret = 0;
+out:
+ if (kmapped_page) {
+ flush_kernel_dcache_page(kmapped_page);
+ kunmap(kmapped_page);
+ put_arg_page(kmapped_page);
+ }
+ return ret;
+}
+
+/*
+ * Like copy_strings, but get argv and its values from kernel memory.
+ */
+int copy_strings_kernel(int argc, const char *const *__argv,
+ struct linux_binprm *bprm)
+{
+ int r;
+ mm_segment_t oldfs = get_fs();
+ struct user_arg_ptr argv = {
+ .ptr.native = (const char __user *const __user *)__argv,
+ };
+
+ set_fs(KERNEL_DS);
+ r = copy_strings(argc, argv, bprm);
+ set_fs(oldfs);
+
+ return r;
+}
+EXPORT_SYMBOL(copy_strings_kernel);
+
+#ifdef CONFIG_MMU
+
+/*
+ * During bprm_mm_init(), we create a temporary stack at STACK_TOP_MAX. Once
+ * the binfmt code determines where the new stack should reside, we shift it to
+ * its final location. The process proceeds as follows:
+ *
+ * 1) Use shift to calculate the new vma endpoints.
+ * 2) Extend vma to cover both the old and new ranges. This ensures the
+ * arguments passed to subsequent functions are consistent.
+ * 3) Move vma's page tables to the new range.
+ * 4) Free up any cleared pgd range.
+ * 5) Shrink the vma to cover only the new range.
+ */
+static int shift_arg_pages(struct vm_area_struct *vma, unsigned long shift)
+{
+ struct mm_struct *mm = vma->vm_mm;
+ unsigned long old_start = vma->vm_start;
+ unsigned long old_end = vma->vm_end;
+ unsigned long length = old_end - old_start;
+ unsigned long new_start = old_start - shift;
+ unsigned long new_end = old_end - shift;
+ struct mmu_gather tlb;
+
+ BUG_ON(new_start > new_end);
+
+ /*
+ * ensure there are no vmas between where we want to go
+ * and where we are
+ */
+ if (vma != find_vma(mm, new_start))
+ return -EFAULT;
+
+ /*
+ * cover the whole range: [new_start, old_end)
+ */
+ if (vma_adjust(vma, new_start, old_end, vma->vm_pgoff, NULL))
+ return -ENOMEM;
+
+ /*
+ * move the page tables downwards, on failure we rely on
+ * process cleanup to remove whatever mess we made.
+ */
+ if (length != move_page_tables(vma, old_start,
+ vma, new_start, length))
+ return -ENOMEM;
+
+ lru_add_drain();
+ tlb_gather_mmu(&tlb, mm, 0);
+ if (new_end > old_start) {
+ /*
+ * when the old and new regions overlap clear from new_end.
+ */
+ free_pgd_range(&tlb, new_end, old_end, new_end,
+ vma->vm_next ? vma->vm_next->vm_start : USER_PGTABLES_CEILING);
+ } else {
+ /*
+ * otherwise, clean from old_start; this is done to not touch
+ * the address space in [new_end, old_start) some architectures
+ * have constraints on va-space that make this illegal (IA64) -
+ * for the others its just a little faster.
+ */
+ free_pgd_range(&tlb, old_start, old_end, new_end,
+ vma->vm_next ? vma->vm_next->vm_start : USER_PGTABLES_CEILING);
+ }
+ tlb_finish_mmu(&tlb, new_end, old_end);
+
+ /*
+ * Shrink the vma to just the new range. Always succeeds.
+ */
+ vma_adjust(vma, new_start, new_end, vma->vm_pgoff, NULL);
+
+ return 0;
+}
+
+/*
+ * Finalizes the stack vm_area_struct. The flags and permissions are updated,
+ * the stack is optionally relocated, and some extra space is added.
+ */
+int setup_arg_pages(struct linux_binprm *bprm,
+ unsigned long stack_top,
+ int executable_stack)
+{
+ unsigned long ret;
+ unsigned long stack_shift;
+ struct mm_struct *mm = current->mm;
+ struct vm_area_struct *vma = bprm->vma;
+ struct vm_area_struct *prev = NULL;
+ unsigned long vm_flags;
+ unsigned long stack_base;
+ unsigned long stack_size;
+ unsigned long stack_expand;
+ unsigned long rlim_stack;
+
+#ifdef CONFIG_STACK_GROWSUP
+ /* Limit stack size to 1GB */
+ stack_base = rlimit_max(RLIMIT_STACK);
+ if (stack_base > (1 << 30))
+ stack_base = 1 << 30;
+
+ /* Make sure we didn't let the argument array grow too large. */
+ if (vma->vm_end - vma->vm_start > stack_base)
+ return -ENOMEM;
+
+ stack_base = PAGE_ALIGN(stack_top - stack_base);
+
+ stack_shift = vma->vm_start - stack_base;
+ mm->arg_start = bprm->p - stack_shift;
+ bprm->p = vma->vm_end - stack_shift;
+#else
+ stack_top = arch_align_stack(stack_top);
+ stack_top = PAGE_ALIGN(stack_top);
+
+ if (unlikely(stack_top < mmap_min_addr) ||
+ unlikely(vma->vm_end - vma->vm_start >= stack_top - mmap_min_addr))
+ return -ENOMEM;
+
+ stack_shift = vma->vm_end - stack_top;
+
+ bprm->p -= stack_shift;
+ mm->arg_start = bprm->p;
+#endif
+
+ if (bprm->loader)
+ bprm->loader -= stack_shift;
+ bprm->exec -= stack_shift;
+
+ down_write(&mm->mmap_sem);
+ vm_flags = VM_STACK_FLAGS;
+
+ /*
+ * Adjust stack execute permissions; explicitly enable for
+ * EXSTACK_ENABLE_X, disable for EXSTACK_DISABLE_X and leave alone
+ * (arch default) otherwise.
+ */
+ if (unlikely(executable_stack == EXSTACK_ENABLE_X))
+ vm_flags |= VM_EXEC;
+ else if (executable_stack == EXSTACK_DISABLE_X)
+ vm_flags &= ~VM_EXEC;
+ vm_flags |= mm->def_flags;
+ vm_flags |= VM_STACK_INCOMPLETE_SETUP;
+
+ ret = mprotect_fixup(vma, &prev, vma->vm_start, vma->vm_end,
+ vm_flags);
+ if (ret)
+ goto out_unlock;
+ BUG_ON(prev != vma);
+
+ /* Move stack pages down in memory. */
+ if (stack_shift) {
+ ret = shift_arg_pages(vma, stack_shift);
+ if (ret)
+ goto out_unlock;
+ }
+
+ /* mprotect_fixup is overkill to remove the temporary stack flags */
+ vma->vm_flags &= ~VM_STACK_INCOMPLETE_SETUP;
+
+ stack_expand = 131072UL; /* randomly 32*4k (or 2*64k) pages */
+ stack_size = vma->vm_end - vma->vm_start;
+ /*
+ * Align this down to a page boundary as expand_stack
+ * will align it up.
+ */
+ rlim_stack = rlimit(RLIMIT_STACK) & PAGE_MASK;
+#ifdef CONFIG_STACK_GROWSUP
+ if (stack_size + stack_expand > rlim_stack)
+ stack_base = vma->vm_start + rlim_stack;
+ else
+ stack_base = vma->vm_end + stack_expand;
+#else
+ if (stack_size + stack_expand > rlim_stack)
+ stack_base = vma->vm_end - rlim_stack;
+ else
+ stack_base = vma->vm_start - stack_expand;
+#endif
+ current->mm->start_stack = bprm->p;
+ ret = expand_stack(vma, stack_base);
+ if (ret)
+ ret = -EFAULT;
+
+out_unlock:
+ up_write(&mm->mmap_sem);
+ return ret;
+}
+EXPORT_SYMBOL(setup_arg_pages);
+
+#endif /* CONFIG_MMU */
+
+struct file *open_exec(const char *name)
+{
+ struct file *file;
+ int err;
+ static const struct open_flags open_exec_flags = {
+ .open_flag = O_LARGEFILE | O_RDONLY | __FMODE_EXEC,
+ .acc_mode = MAY_EXEC | MAY_OPEN,
+ .intent = LOOKUP_OPEN
+ };
+
+ file = do_filp_open(AT_FDCWD, name, &open_exec_flags, LOOKUP_FOLLOW);
+ if (IS_ERR(file))
+ goto out;
+
+ err = -EACCES;
+ if (!S_ISREG(file->f_path.dentry->d_inode->i_mode))
+ goto exit;
+
+ if (file->f_path.mnt->mnt_flags & MNT_NOEXEC)
+ goto exit;
+
+ fsnotify_open(file);
+
+ err = deny_write_access(file);
+ if (err)
+ goto exit;
+
+out:
+ return file;
+
+exit:
+ fput(file);
+ return ERR_PTR(err);
+}
+EXPORT_SYMBOL(open_exec);
+
+int kernel_read(struct file *file, loff_t offset,
+ char *addr, unsigned long count)
+{
+ mm_segment_t old_fs;
+ loff_t pos = offset;
+ int result;
+
+ old_fs = get_fs();
+ set_fs(get_ds());
+ /* The cast to a user pointer is valid due to the set_fs() */
+ result = vfs_read(file, (void __user *)addr, count, &pos);
+ set_fs(old_fs);
+ return result;
+}
+
+EXPORT_SYMBOL(kernel_read);
+
+static int exec_mmap(struct mm_struct *mm)
+{
+ struct task_struct *tsk;
+ struct mm_struct * old_mm, *active_mm;
+
+ /* Notify parent that we're no longer interested in the old VM */
+ tsk = current;
+ old_mm = current->mm;
+ mm_release(tsk, old_mm);
+
+ if (old_mm) {
+ sync_mm_rss(old_mm);
+ /*
+ * Make sure that if there is a core dump in progress
+ * for the old mm, we get out and die instead of going
+ * through with the exec. We must hold mmap_sem around
+ * checking core_state and changing tsk->mm.
+ */
+ down_read(&old_mm->mmap_sem);
+ if (unlikely(old_mm->core_state)) {
+ up_read(&old_mm->mmap_sem);
+ return -EINTR;
+ }
+ }
+ task_lock(tsk);
+ preempt_disable_rt();
+ active_mm = tsk->active_mm;
+ tsk->mm = mm;
+ tsk->active_mm = mm;
+ activate_mm(active_mm, mm);
+ preempt_enable_rt();
+ task_unlock(tsk);
+ arch_pick_mmap_layout(mm);
+ if (old_mm) {
+ up_read(&old_mm->mmap_sem);
+ BUG_ON(active_mm != old_mm);
+ setmax_mm_hiwater_rss(&tsk->signal->maxrss, old_mm);
+ mm_update_next_owner(old_mm);
+ mmput(old_mm);
+ return 0;
+ }
+ mmdrop(active_mm);
+ return 0;
+}
+
+/*
+ * This function makes sure the current process has its own signal table,
+ * so that flush_signal_handlers can later reset the handlers without
+ * disturbing other processes. (Other processes might share the signal
+ * table via the CLONE_SIGHAND option to clone().)
+ */
+static int de_thread(struct task_struct *tsk)
+{
+ struct signal_struct *sig = tsk->signal;
+ struct sighand_struct *oldsighand = tsk->sighand;
+ spinlock_t *lock = &oldsighand->siglock;
+
+ if (thread_group_empty(tsk))
+ goto no_thread_group;
+
+ /*
+ * Kill all other threads in the thread group.
+ */
+ spin_lock_irq(lock);
+ if (signal_group_exit(sig)) {
+ /*
+ * Another group action in progress, just
+ * return so that the signal is processed.
+ */
+ spin_unlock_irq(lock);
+ return -EAGAIN;
+ }
+
+ sig->group_exit_task = tsk;
+ sig->notify_count = zap_other_threads(tsk);
+ if (!thread_group_leader(tsk))
+ sig->notify_count--;
+
+ while (sig->notify_count) {
+ __set_current_state(TASK_UNINTERRUPTIBLE);
+ spin_unlock_irq(lock);
+ schedule();
+ spin_lock_irq(lock);
+ }
+ spin_unlock_irq(lock);
+
+ /*
+ * At this point all other threads have exited, all we have to
+ * do is to wait for the thread group leader to become inactive,
+ * and to assume its PID:
+ */
+ if (!thread_group_leader(tsk)) {
+ struct task_struct *leader = tsk->group_leader;
+
+ sig->notify_count = -1; /* for exit_notify() */
+ for (;;) {
+ threadgroup_change_begin(tsk);
+ write_lock_irq(&tasklist_lock);
+ if (likely(leader->exit_state))
+ break;
+ __set_current_state(TASK_UNINTERRUPTIBLE);
+ write_unlock_irq(&tasklist_lock);
+ threadgroup_change_end(tsk);
+ schedule();
+ }
+
+ /*
+ * The only record we have of the real-time age of a
+ * process, regardless of execs it's done, is start_time.
+ * All the past CPU time is accumulated in signal_struct
+ * from sister threads now dead. But in this non-leader
+ * exec, nothing survives from the original leader thread,
+ * whose birth marks the true age of this process now.
+ * When we take on its identity by switching to its PID, we
+ * also take its birthdate (always earlier than our own).
+ */
+ tsk->start_time = leader->start_time;
+
+ BUG_ON(!same_thread_group(leader, tsk));
+ BUG_ON(has_group_leader_pid(tsk));
+ /*
+ * An exec() starts a new thread group with the
+ * TGID of the previous thread group. Rehash the
+ * two threads with a switched PID, and release
+ * the former thread group leader:
+ */
+
+ /* Become a process group leader with the old leader's pid.
+ * The old leader becomes a thread of the this thread group.
+ * Note: The old leader also uses this pid until release_task
+ * is called. Odd but simple and correct.
+ */
+ detach_pid(tsk, PIDTYPE_PID);
+ tsk->pid = leader->pid;
+ attach_pid(tsk, PIDTYPE_PID, task_pid(leader));
+ transfer_pid(leader, tsk, PIDTYPE_PGID);
+ transfer_pid(leader, tsk, PIDTYPE_SID);
+
+ list_replace_rcu(&leader->tasks, &tsk->tasks);
+ list_replace_init(&leader->sibling, &tsk->sibling);
+
+ tsk->group_leader = tsk;
+ leader->group_leader = tsk;
+
+ tsk->exit_signal = SIGCHLD;
+ leader->exit_signal = -1;
+
+ BUG_ON(leader->exit_state != EXIT_ZOMBIE);
+ leader->exit_state = EXIT_DEAD;
+
+ /*
+ * We are going to release_task()->ptrace_unlink() silently,
+ * the tracer can sleep in do_wait(). EXIT_DEAD guarantees
+ * the tracer wont't block again waiting for this thread.
+ */
+ if (unlikely(leader->ptrace))
+ __wake_up_parent(leader, leader->parent);
+ write_unlock_irq(&tasklist_lock);
+ threadgroup_change_end(tsk);
+
+ release_task(leader);
+ }
+
+ sig->group_exit_task = NULL;
+ sig->notify_count = 0;
+
+no_thread_group:
+ /* we have changed execution domain */
+ tsk->exit_signal = SIGCHLD;
+
+ exit_itimers(sig);
+ flush_itimer_signals();
+
+ if (atomic_read(&oldsighand->count) != 1) {
+ struct sighand_struct *newsighand;
+ /*
+ * This ->sighand is shared with the CLONE_SIGHAND
+ * but not CLONE_THREAD task, switch to the new one.
+ */
+ newsighand = kmem_cache_alloc(sighand_cachep, GFP_KERNEL);
+ if (!newsighand)
+ return -ENOMEM;
+
+ atomic_set(&newsighand->count, 1);
+ memcpy(newsighand->action, oldsighand->action,
+ sizeof(newsighand->action));
+
+ write_lock_irq(&tasklist_lock);
+ spin_lock(&oldsighand->siglock);
+ rcu_assign_pointer(tsk->sighand, newsighand);
+ spin_unlock(&oldsighand->siglock);
+ write_unlock_irq(&tasklist_lock);
+
+ __cleanup_sighand(oldsighand);
+ }
+
+ BUG_ON(!thread_group_leader(tsk));
+ return 0;
+}
+
+/*
+ * These functions flushes out all traces of the currently running executable
+ * so that a new one can be started
+ */
+static void flush_old_files(struct files_struct * files)
+{
+ long j = -1;
+ struct fdtable *fdt;
+
+ spin_lock(&files->file_lock);
+ for (;;) {
+ unsigned long set, i;
+
+ j++;
+ i = j * BITS_PER_LONG;
+ fdt = files_fdtable(files);
+ if (i >= fdt->max_fds)
+ break;
+ set = fdt->close_on_exec[j];
+ if (!set)
+ continue;
+ fdt->close_on_exec[j] = 0;
+ spin_unlock(&files->file_lock);
+ for ( ; set ; i++,set >>= 1) {
+ if (set & 1) {
+ sys_close(i);
+ }
+ }
+ spin_lock(&files->file_lock);
+
+ }
+ spin_unlock(&files->file_lock);
+}
+
+char *get_task_comm(char *buf, struct task_struct *tsk)
+{
+ /* buf must be at least sizeof(tsk->comm) in size */
+ task_lock(tsk);
+ strncpy(buf, tsk->comm, sizeof(tsk->comm));
+ task_unlock(tsk);
+ return buf;
+}
+EXPORT_SYMBOL_GPL(get_task_comm);
+
+void set_task_comm(struct task_struct *tsk, char *buf)
+{
+ task_lock(tsk);
+
+ trace_task_rename(tsk, buf);
+
+ /*
+ * Threads may access current->comm without holding
+ * the task lock, so write the string carefully.
+ * Readers without a lock may see incomplete new
+ * names but are safe from non-terminating string reads.
+ */
+ memset(tsk->comm, 0, TASK_COMM_LEN);
+ wmb();
+ strlcpy(tsk->comm, buf, sizeof(tsk->comm));
+ task_unlock(tsk);
+ perf_event_comm(tsk);
+}
+
+static void filename_to_taskname(char *tcomm, const char *fn, unsigned int len)
+{
+ int i, ch;
+
+ /* Copies the binary name from after last slash */
+ for (i = 0; (ch = *(fn++)) != '\0';) {
+ if (ch == '/')
+ i = 0; /* overwrite what we wrote */
+ else
+ if (i < len - 1)
+ tcomm[i++] = ch;
+ }
+ tcomm[i] = '\0';
+}
+
+int flush_old_exec(struct linux_binprm * bprm)
+{
+ int retval;
+
+ /*
+ * Make sure we have a private signal table and that
+ * we are unassociated from the previous thread group.
+ */
+ retval = de_thread(current);
+ if (retval)
+ goto out;
+
+ set_mm_exe_file(bprm->mm, bprm->file);
+
+ filename_to_taskname(bprm->tcomm, bprm->filename, sizeof(bprm->tcomm));
+ /*
+ * Release all of the old mmap stuff
+ */
+ acct_arg_size(bprm, 0);
+ retval = exec_mmap(bprm->mm);
+ if (retval)
+ goto out;
+
+ bprm->mm = NULL; /* We're using it now */
+
+ set_fs(USER_DS);
+ current->flags &=
+ ~(PF_RANDOMIZE | PF_FORKNOEXEC | PF_KTHREAD | PF_NOFREEZE);
+ flush_thread();
+ current->personality &= ~bprm->per_clear;
+
+ return 0;
+
+out:
+ return retval;
+}
+EXPORT_SYMBOL(flush_old_exec);
+
+void would_dump(struct linux_binprm *bprm, struct file *file)
+{
+ if (inode_permission(file->f_path.dentry->d_inode, MAY_READ) < 0)
+ bprm->interp_flags |= BINPRM_FLAGS_ENFORCE_NONDUMP;
+}
+EXPORT_SYMBOL(would_dump);
+
+void setup_new_exec(struct linux_binprm * bprm)
+{
+ arch_pick_mmap_layout(current->mm);
+
+ /* This is the point of no return */
+ current->sas_ss_sp = current->sas_ss_size = 0;
+
+ if (current_euid() == current_uid() && current_egid() == current_gid())
+ set_dumpable(current->mm, 1);
+ else
+ set_dumpable(current->mm, suid_dumpable);
+
+ set_task_comm(current, bprm->tcomm);
+
+ /* Set the new mm task size. We have to do that late because it may
+ * depend on TIF_32BIT which is only updated in flush_thread() on
+ * some architectures like powerpc
+ */
+ current->mm->task_size = TASK_SIZE;
+
+ /* install the new credentials */
+ if (bprm->cred->uid != current_euid() ||
+ bprm->cred->gid != current_egid()) {
+ current->pdeath_signal = 0;
+ } else {
+ would_dump(bprm, bprm->file);
+ if (bprm->interp_flags & BINPRM_FLAGS_ENFORCE_NONDUMP)
+ set_dumpable(current->mm, suid_dumpable);
+ }
+
+ /* An exec changes our domain. We are no longer part of the thread
+ group */
+
+ current->self_exec_id++;
+
+ flush_signal_handlers(current, 0);
+ flush_old_files(current->files);
+}
+EXPORT_SYMBOL(setup_new_exec);
+
+/*
+ * Prepare credentials and lock ->cred_guard_mutex.
+ * install_exec_creds() commits the new creds and drops the lock.
+ * Or, if exec fails before, free_bprm() should release ->cred and
+ * and unlock.
+ */
+int prepare_bprm_creds(struct linux_binprm *bprm)
+{
+ if (mutex_lock_interruptible(¤t->signal->cred_guard_mutex))
+ return -ERESTARTNOINTR;
+
+ bprm->cred = prepare_exec_creds();
+ if (likely(bprm->cred))
+ return 0;
+
+ mutex_unlock(¤t->signal->cred_guard_mutex);
+ return -ENOMEM;
+}
+
+void free_bprm(struct linux_binprm *bprm)
+{
+ free_arg_pages(bprm);
+ if (bprm->cred) {
+ mutex_unlock(¤t->signal->cred_guard_mutex);
+ abort_creds(bprm->cred);
+ }
+ /* If a binfmt changed the interp, free it. */
+ if (bprm->interp != bprm->filename)
+ kfree(bprm->interp);
+ kfree(bprm);
+}
+
+int bprm_change_interp(char *interp, struct linux_binprm *bprm)
+{
+ /* If a binfmt changed the interp, free it first. */
+ if (bprm->interp != bprm->filename)
+ kfree(bprm->interp);
+ bprm->interp = kstrdup(interp, GFP_KERNEL);
+ if (!bprm->interp)
+ return -ENOMEM;
+ return 0;
+}
+EXPORT_SYMBOL(bprm_change_interp);
+
+/*
+ * install the new credentials for this executable
+ */
+void install_exec_creds(struct linux_binprm *bprm)
+{
+ security_bprm_committing_creds(bprm);
+
+ commit_creds(bprm->cred);
+ bprm->cred = NULL;
+
+ /*
+ * Disable monitoring for regular users
+ * when executing setuid binaries. Must
+ * wait until new credentials are committed
+ * by commit_creds() above
+ */
+ if (get_dumpable(current->mm) != SUID_DUMP_USER)
+ perf_event_exit_task(current);
+ /*
+ * cred_guard_mutex must be held at least to this point to prevent
+ * ptrace_attach() from altering our determination of the task's
+ * credentials; any time after this it may be unlocked.
+ */
+ security_bprm_committed_creds(bprm);
+ mutex_unlock(¤t->signal->cred_guard_mutex);
+}
+EXPORT_SYMBOL(install_exec_creds);
+
+static void bprm_fill_uid(struct linux_binprm *bprm)
+{
+ struct inode *inode;
+ unsigned int mode;
+ uid_t uid;
+ gid_t gid;
+
+ /* clear any previous set[ug]id data from a previous binary */
+ bprm->cred->euid = current_euid();
+ bprm->cred->egid = current_egid();
+
+ if (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID)
+ return;
+
+ inode = bprm->file->f_path.dentry->d_inode;
+ mode = ACCESS_ONCE(inode->i_mode);
+ if (!(mode & (S_ISUID|S_ISGID)))
+ return;
+
+ /* Be careful if suid/sgid is set */
+ mutex_lock(&inode->i_mutex);
+
+ /* reload atomically mode/uid/gid now that lock held */
+ mode = inode->i_mode;
+ uid = inode->i_uid;
+ gid = inode->i_gid;
+ mutex_unlock(&inode->i_mutex);
+
+ if (mode & S_ISUID) {
+ bprm->per_clear |= PER_CLEAR_ON_SETID;
+ bprm->cred->euid = uid;
+ }
+
+ if ((mode & (S_ISGID | S_IXGRP)) == (S_ISGID | S_IXGRP)) {
+ bprm->per_clear |= PER_CLEAR_ON_SETID;
+ bprm->cred->egid = gid;
+ }
+}
+
+/*
+ * determine how safe it is to execute the proposed program
+ * - the caller must hold ->cred_guard_mutex to protect against
+ * PTRACE_ATTACH
+ */
+static int check_unsafe_exec(struct linux_binprm *bprm)
+{
+ struct task_struct *p = current, *t;
+ unsigned n_fs;
+ int res = 0;
+
+ if (p->ptrace) {
+ if (p->ptrace & PT_PTRACE_CAP)
+ bprm->unsafe |= LSM_UNSAFE_PTRACE_CAP;
+ else
+ bprm->unsafe |= LSM_UNSAFE_PTRACE;
+ }
+
+ n_fs = 1;
+ spin_lock(&p->fs->lock);
+ rcu_read_lock();
+ for (t = next_thread(p); t != p; t = next_thread(t)) {
+ if (t->fs == p->fs)
+ n_fs++;
+ }
+ rcu_read_unlock();
+
+ if (p->fs->users > n_fs) {
+ bprm->unsafe |= LSM_UNSAFE_SHARE;
+ } else {
+ res = -EAGAIN;
+ if (!p->fs->in_exec) {
+ p->fs->in_exec = 1;
+ res = 1;
+ }
+ }
+ spin_unlock(&p->fs->lock);
+
+ return res;
+}
+
+/*
+ * Fill the binprm structure from the inode.
+ * Check permissions, then read the first 128 (BINPRM_BUF_SIZE) bytes
+ *
+ * This may be called multiple times for binary chains (scripts for example).
+ */
+int prepare_binprm(struct linux_binprm *bprm)
+{
+ int retval;
+
+ if (bprm->file->f_op == NULL)
+ return -EACCES;
+
+ bprm_fill_uid(bprm);
+
+ /* fill in binprm security blob */
+ retval = security_bprm_set_creds(bprm);
+ if (retval)
+ return retval;
+ bprm->cred_prepared = 1;
+
+ memset(bprm->buf, 0, BINPRM_BUF_SIZE);
+ return kernel_read(bprm->file, 0, bprm->buf, BINPRM_BUF_SIZE);
+}
+
+EXPORT_SYMBOL(prepare_binprm);
+
+/*
+ * Arguments are '\0' separated strings found at the location bprm->p
+ * points to; chop off the first by relocating brpm->p to right after
+ * the first '\0' encountered.
+ */
+int remove_arg_zero(struct linux_binprm *bprm)
+{
+ int ret = 0;
+ unsigned long offset;
+ char *kaddr;
+ struct page *page;
+
+ if (!bprm->argc)
+ return 0;
+
+ do {
+ offset = bprm->p & ~PAGE_MASK;
+ page = get_arg_page(bprm, bprm->p, 0);
+ if (!page) {
+ ret = -EFAULT;
+ goto out;
+ }
+ kaddr = kmap_atomic(page);
+
+ for (; offset < PAGE_SIZE && kaddr[offset];
+ offset++, bprm->p++)
+ ;
+
+ kunmap_atomic(kaddr);
+ put_arg_page(page);
+
+ if (offset == PAGE_SIZE)
+ free_arg_page(bprm, (bprm->p >> PAGE_SHIFT) - 1);
+ } while (offset == PAGE_SIZE);
+
+ bprm->p++;
+ bprm->argc--;
+ ret = 0;
+
+out:
+ return ret;
+}
+EXPORT_SYMBOL(remove_arg_zero);
+
+/*
+ * cycle the list of binary formats handler, until one recognizes the image
+ */
+int search_binary_handler(struct linux_binprm *bprm,struct pt_regs *regs)
+{
+ unsigned int depth = bprm->recursion_depth;
+ int try,retval;
+ struct linux_binfmt *fmt;
+ pid_t old_pid, old_vpid;
+
+ /* This allows 4 levels of binfmt rewrites before failing hard. */
+ if (depth > 5)
+ return -ELOOP;
+
+ retval = security_bprm_check(bprm);
+ if (retval)
+ return retval;
+
+ retval = audit_bprm(bprm);
+ if (retval)
+ return retval;
+
+ /* Need to fetch pid before load_binary changes it */
+ old_pid = current->pid;
+ rcu_read_lock();
+ old_vpid = task_pid_nr_ns(current, task_active_pid_ns(current->parent));
+ rcu_read_unlock();
+
+ retval = -ENOENT;
+ for (try=0; try<2; try++) {
+ read_lock(&binfmt_lock);
+ list_for_each_entry(fmt, &formats, lh) {
+ int (*fn)(struct linux_binprm *, struct pt_regs *) = fmt->load_binary;
+ if (!fn)
+ continue;
+ if (!try_module_get(fmt->module))
+ continue;
+ read_unlock(&binfmt_lock);
+ bprm->recursion_depth = depth + 1;
+ retval = fn(bprm, regs);
+ bprm->recursion_depth = depth;
+ if (retval >= 0) {
+ if (depth == 0) {
+ trace_sched_process_exec(current, old_pid, bprm);
+ ptrace_event(PTRACE_EVENT_EXEC, old_vpid);
+ }
+ put_binfmt(fmt);
+ allow_write_access(bprm->file);
+ if (bprm->file)
+ fput(bprm->file);
+ bprm->file = NULL;
+ current->did_exec = 1;
+ proc_exec_connector(current);
+ return retval;
+ }
+ read_lock(&binfmt_lock);
+ put_binfmt(fmt);
+ if (retval != -ENOEXEC || bprm->mm == NULL)
+ break;
+ if (!bprm->file) {
+ read_unlock(&binfmt_lock);
+ return retval;
+ }
+ }
+ read_unlock(&binfmt_lock);
+#ifdef CONFIG_MODULES
+ if (retval != -ENOEXEC || bprm->mm == NULL) {
+ break;
+ } else {
+#define printable(c) (((c)=='\t') || ((c)=='\n') || (0x20<=(c) && (c)<=0x7e))
+ if (printable(bprm->buf[0]) &&
+ printable(bprm->buf[1]) &&
+ printable(bprm->buf[2]) &&
+ printable(bprm->buf[3]))
+ break; /* -ENOEXEC */
+ if (try)
+ break; /* -ENOEXEC */
+ request_module("binfmt-%04x", *(unsigned short *)(&bprm->buf[2]));
+ }
+#else
+ break;
+#endif
+ }
+ return retval;
+}
+
+EXPORT_SYMBOL(search_binary_handler);
+
+/*
+ * sys_execve() executes a new program.
+ */
+static int do_execve_common(const char *filename,
+ struct user_arg_ptr argv,
+ struct user_arg_ptr envp,
+ struct pt_regs *regs)
+{
+ struct linux_binprm *bprm;
+ struct file *file;
+ struct files_struct *displaced;
+ bool clear_in_exec;
+ int retval;
+ const struct cred *cred = current_cred();
+
+ /*
+ * We move the actual failure in case of RLIMIT_NPROC excess from
+ * set*uid() to execve() because too many poorly written programs
+ * don't check setuid() return code. Here we additionally recheck
+ * whether NPROC limit is still exceeded.
+ */
+ if ((current->flags & PF_NPROC_EXCEEDED) &&
+ atomic_read(&cred->user->processes) > rlimit(RLIMIT_NPROC)) {
+ retval = -EAGAIN;
+ goto out_ret;
+ }
+
+ /* We're below the limit (still or again), so we don't want to make
+ * further execve() calls fail. */
+ current->flags &= ~PF_NPROC_EXCEEDED;
+
+ retval = unshare_files(&displaced);
+ if (retval)
+ goto out_ret;
+
+ retval = -ENOMEM;
+ bprm = kzalloc(sizeof(*bprm), GFP_KERNEL);
+ if (!bprm)
+ goto out_files;
+
+ retval = prepare_bprm_creds(bprm);
+ if (retval)
+ goto out_free;
+
+ retval = check_unsafe_exec(bprm);
+ if (retval < 0)
+ goto out_free;
+ clear_in_exec = retval;
+ current->in_execve = 1;
+
+ file = open_exec(filename);
+ retval = PTR_ERR(file);
+ if (IS_ERR(file))
+ goto out_unmark;
+
+ sched_exec();
+
+ bprm->file = file;
+ bprm->filename = filename;
+ bprm->interp = filename;
+
+ retval = bprm_mm_init(bprm);
+ if (retval)
+ goto out_file;
+
+ bprm->argc = count(argv, MAX_ARG_STRINGS);
+ if ((retval = bprm->argc) < 0)
+ goto out;
+
+ bprm->envc = count(envp, MAX_ARG_STRINGS);
+ if ((retval = bprm->envc) < 0)
+ goto out;
+
+ retval = prepare_binprm(bprm);
+ if (retval < 0)
+ goto out;
+
+ retval = copy_strings_kernel(1, &bprm->filename, bprm);
+ if (retval < 0)
+ goto out;
+
+ bprm->exec = bprm->p;
+ retval = copy_strings(bprm->envc, envp, bprm);
+ if (retval < 0)
+ goto out;
+
+ retval = copy_strings(bprm->argc, argv, bprm);
+ if (retval < 0)
+ goto out;
+
+ retval = search_binary_handler(bprm,regs);
+ if (retval < 0)
+ goto out;
+
+ /* execve succeeded */
+ current->fs->in_exec = 0;
+ current->in_execve = 0;
+ acct_update_integrals(current);
+ free_bprm(bprm);
+ if (displaced)
+ put_files_struct(displaced);
+ return retval;
+
+out:
+ if (bprm->mm) {
+ acct_arg_size(bprm, 0);
+ mmput(bprm->mm);
+ }
+
+out_file:
+ if (bprm->file) {
+ allow_write_access(bprm->file);
+ fput(bprm->file);
+ }
+
+out_unmark:
+ if (clear_in_exec)
+ current->fs->in_exec = 0;
+ current->in_execve = 0;
+
+out_free:
+ free_bprm(bprm);
+
+out_files:
+ if (displaced)
+ reset_files_struct(displaced);
+out_ret:
+ return retval;
+}
+
+int do_execve(const char *filename,
+ const char __user *const __user *__argv,
+ const char __user *const __user *__envp,
+ struct pt_regs *regs)
+{
+ struct user_arg_ptr argv = { .ptr.native = __argv };
+ struct user_arg_ptr envp = { .ptr.native = __envp };
+ return do_execve_common(filename, argv, envp, regs);
+}
+
+#ifdef CONFIG_COMPAT
+int compat_do_execve(char *filename,
+ compat_uptr_t __user *__argv,
+ compat_uptr_t __user *__envp,
+ struct pt_regs *regs)
+{
+ struct user_arg_ptr argv = {
+ .is_compat = true,
+ .ptr.compat = __argv,
+ };
+ struct user_arg_ptr envp = {
+ .is_compat = true,
+ .ptr.compat = __envp,
+ };
+ return do_execve_common(filename, argv, envp, regs);
+}
+#endif
+
+void set_binfmt(struct linux_binfmt *new)
+{
+ struct mm_struct *mm = current->mm;
+
+ if (mm->binfmt)
+ module_put(mm->binfmt->module);
+
+ mm->binfmt = new;
+ if (new)
+ __module_get(new->module);
+}
+
+EXPORT_SYMBOL(set_binfmt);
+
+static int expand_corename(struct core_name *cn)
+{
+ char *old_corename = cn->corename;
+
+ cn->size = CORENAME_MAX_SIZE * atomic_inc_return(&call_count);
+ cn->corename = krealloc(old_corename, cn->size, GFP_KERNEL);
+
+ if (!cn->corename) {
+ kfree(old_corename);
+ return -ENOMEM;
+ }
+
+ return 0;
+}
+
+static int cn_printf(struct core_name *cn, const char *fmt, ...)
+{
+ char *cur;
+ int need;
+ int ret;
+ va_list arg;
+
+ va_start(arg, fmt);
+ need = vsnprintf(NULL, 0, fmt, arg);
+ va_end(arg);
+
+ if (likely(need < cn->size - cn->used - 1))
+ goto out_printf;
+
+ ret = expand_corename(cn);
+ if (ret)
+ goto expand_fail;
+
+out_printf:
+ cur = cn->corename + cn->used;
+ va_start(arg, fmt);
+ vsnprintf(cur, need + 1, fmt, arg);
+ va_end(arg);
+ cn->used += need;
+ return 0;
+
+expand_fail:
+ return ret;
+}
+
+static void cn_escape(char *str)
+{
+ for (; *str; str++)
+ if (*str == '/')
+ *str = '!';
+}
+
+static int cn_print_exe_file(struct core_name *cn)
+{
+ struct file *exe_file;
+ char *pathbuf, *path;
+ int ret;
+
+ exe_file = get_mm_exe_file(current->mm);
+ if (!exe_file) {
+ char *commstart = cn->corename + cn->used;
+ ret = cn_printf(cn, "%s (path unknown)", current->comm);
+ cn_escape(commstart);
+ return ret;
+ }
+
+ pathbuf = kmalloc(PATH_MAX, GFP_TEMPORARY);
+ if (!pathbuf) {
+ ret = -ENOMEM;
+ goto put_exe_file;
+ }
+
+ path = d_path(&exe_file->f_path, pathbuf, PATH_MAX);
+ if (IS_ERR(path)) {
+ ret = PTR_ERR(path);
+ goto free_buf;
+ }
+
+ cn_escape(path);
+
+ ret = cn_printf(cn, "%s", path);
+
+free_buf:
+ kfree(pathbuf);
+put_exe_file:
+ fput(exe_file);
+ return ret;
+}
+
+/* format_corename will inspect the pattern parameter, and output a
+ * name into corename, which must have space for at least
+ * CORENAME_MAX_SIZE bytes plus one byte for the zero terminator.
+ */
+static int format_corename(struct core_name *cn, long signr)
+{
+ const struct cred *cred = current_cred();
+ const char *pat_ptr = core_pattern;
+ int ispipe = (*pat_ptr == '|');
+ int pid_in_pattern = 0;
+ int err = 0;
+
+ cn->size = CORENAME_MAX_SIZE * atomic_read(&call_count);
+ cn->corename = kmalloc(cn->size, GFP_KERNEL);
+ cn->used = 0;
+
+ if (!cn->corename)
+ return -ENOMEM;
+
+ /* Repeat as long as we have more pattern to process and more output
+ space */
+ while (*pat_ptr) {
+ if (*pat_ptr != '%') {
+ if (*pat_ptr == 0)
+ goto out;
+ err = cn_printf(cn, "%c", *pat_ptr++);
+ } else {
+ switch (*++pat_ptr) {
+ /* single % at the end, drop that */
+ case 0:
+ goto out;
+ /* Double percent, output one percent */
+ case '%':
+ err = cn_printf(cn, "%c", '%');
+ break;
+ /* pid */
+ case 'p':
+ pid_in_pattern = 1;
+ err = cn_printf(cn, "%d",
+ task_tgid_vnr(current));
+ break;
+ /* uid */
+ case 'u':
+ err = cn_printf(cn, "%d", cred->uid);
+ break;
+ /* gid */
+ case 'g':
+ err = cn_printf(cn, "%d", cred->gid);
+ break;
+ /* signal that caused the coredump */
+ case 's':
+ err = cn_printf(cn, "%ld", signr);
+ break;
+ /* UNIX time of coredump */
+ case 't': {
+ struct timeval tv;
+ do_gettimeofday(&tv);
+ err = cn_printf(cn, "%lu", tv.tv_sec);
+ break;
+ }
+ /* hostname */
+ case 'h': {
+ char *namestart = cn->corename + cn->used;
+ down_read(&uts_sem);
+ err = cn_printf(cn, "%s",
+ utsname()->nodename);
+ up_read(&uts_sem);
+ cn_escape(namestart);
+ break;
+ }
+ /* executable */
+ case 'e': {
+ char *commstart = cn->corename + cn->used;
+ err = cn_printf(cn, "%s", current->comm);
+ cn_escape(commstart);
+ break;
+ }
+ case 'E':
+ err = cn_print_exe_file(cn);
+ break;
+ /* core limit size */
+ case 'c':
+ err = cn_printf(cn, "%lu",
+ rlimit(RLIMIT_CORE));
+ break;
+ default:
+ break;
+ }
+ ++pat_ptr;
+ }
+
+ if (err)
+ return err;
+ }
+
+ /* Backward compatibility with core_uses_pid:
+ *
+ * If core_pattern does not include a %p (as is the default)
+ * and core_uses_pid is set, then .%pid will be appended to
+ * the filename. Do not do this for piped commands. */
+ if (!ispipe && !pid_in_pattern && core_uses_pid) {
+ err = cn_printf(cn, ".%d", task_tgid_vnr(current));
+ if (err)
+ return err;
+ }
+out:
+ return ispipe;
+}
+
+static int zap_process(struct task_struct *start, int exit_code)
+{
+ struct task_struct *t;
+ int nr = 0;
+
+ start->signal->flags = SIGNAL_GROUP_EXIT;
+ start->signal->group_exit_code = exit_code;
+ start->signal->group_stop_count = 0;
+
+ t = start;
+ do {
+ task_clear_jobctl_pending(t, JOBCTL_PENDING_MASK);
+ if (t != current && t->mm) {
+#ifndef CONFIG_RAMDUMP
+ sigaddset(&t->pending.signal, SIGKILL);
+ signal_wake_up(t, 1);
+#endif
+ nr++;
+ }
+ } while_each_thread(start, t);
+
+ return nr;
+}
+
+static inline int zap_threads(struct task_struct *tsk, struct mm_struct *mm,
+ struct core_state *core_state, int exit_code)
+{
+ struct task_struct *g, *p;
+ unsigned long flags;
+ int nr = -EAGAIN;
+
+ spin_lock_irq(&tsk->sighand->siglock);
+ if (!signal_group_exit(tsk->signal)) {
+ mm->core_state = core_state;
+ nr = zap_process(tsk, exit_code);
+ }
+ spin_unlock_irq(&tsk->sighand->siglock);
+ if (unlikely(nr < 0))
+ return nr;
+
+ if (atomic_read(&mm->mm_users) == nr + 1)
+ goto done;
+ /*
+ * We should find and kill all tasks which use this mm, and we should
+ * count them correctly into ->nr_threads. We don't take tasklist
+ * lock, but this is safe wrt:
+ *
+ * fork:
+ * None of sub-threads can fork after zap_process(leader). All
+ * processes which were created before this point should be
+ * visible to zap_threads() because copy_process() adds the new
+ * process to the tail of init_task.tasks list, and lock/unlock
+ * of ->siglock provides a memory barrier.
+ *
+ * do_exit:
+ * The caller holds mm->mmap_sem. This means that the task which
+ * uses this mm can't pass exit_mm(), so it can't exit or clear
+ * its ->mm.
+ *
+ * de_thread:
+ * It does list_replace_rcu(&leader->tasks, ¤t->tasks),
+ * we must see either old or new leader, this does not matter.
+ * However, it can change p->sighand, so lock_task_sighand(p)
+ * must be used. Since p->mm != NULL and we hold ->mmap_sem
+ * it can't fail.
+ *
+ * Note also that "g" can be the old leader with ->mm == NULL
+ * and already unhashed and thus removed from ->thread_group.
+ * This is OK, __unhash_process()->list_del_rcu() does not
+ * clear the ->next pointer, we will find the new leader via
+ * next_thread().
+ */
+ rcu_read_lock();
+ for_each_process(g) {
+ if (g == tsk->group_leader)
+ continue;
+ if (g->flags & PF_KTHREAD)
+ continue;
+ p = g;
+ do {
+ if (p->mm) {
+ if (unlikely(p->mm == mm)) {
+ lock_task_sighand(p, &flags);
+ nr += zap_process(p, exit_code);
+ unlock_task_sighand(p, &flags);
+ }
+ break;
+ }
+ } while_each_thread(g, p);
+ }
+ rcu_read_unlock();
+done:
+ atomic_set(&core_state->nr_threads, nr);
+ return nr;
+}
+
+static int coredump_wait(int exit_code, struct core_state *core_state)
+{
+ struct task_struct *tsk = current;
+ struct mm_struct *mm = tsk->mm;
+ int core_waiters = -EBUSY;
+
+ init_completion(&core_state->startup);
+ core_state->dumper.task = tsk;
+ core_state->dumper.next = NULL;
+
+ down_write(&mm->mmap_sem);
+ if (!mm->core_state)
+ core_waiters = zap_threads(tsk, mm, core_state, exit_code);
+ up_write(&mm->mmap_sem);
+#ifndef CONFIG_RAMDUMP
+ if (core_waiters > 0)
+ wait_for_completion(&core_state->startup);
+#endif
+
+ return core_waiters;
+}
+
+static void coredump_finish(struct mm_struct *mm)
+{
+ struct core_thread *curr, *next;
+ struct task_struct *task;
+
+ next = mm->core_state->dumper.next;
+ while ((curr = next) != NULL) {
+ next = curr->next;
+ task = curr->task;
+ /*
+ * see exit_mm(), curr->task must not see
+ * ->task == NULL before we read ->next.
+ */
+ smp_mb();
+ curr->task = NULL;
+ wake_up_process(task);
+ }
+
+ mm->core_state = NULL;
+}
+
+/*
+ * set_dumpable converts traditional three-value dumpable to two flags and
+ * stores them into mm->flags. It modifies lower two bits of mm->flags, but
+ * these bits are not changed atomically. So get_dumpable can observe the
+ * intermediate state. To avoid doing unexpected behavior, get get_dumpable
+ * return either old dumpable or new one by paying attention to the order of
+ * modifying the bits.
+ *
+ * dumpable | mm->flags (binary)
+ * old new | initial interim final
+ * ---------+-----------------------
+ * 0 1 | 00 01 01
+ * 0 2 | 00 10(*) 11
+ * 1 0 | 01 00 00
+ * 1 2 | 01 11 11
+ * 2 0 | 11 10(*) 00
+ * 2 1 | 11 11 01
+ *
+ * (*) get_dumpable regards interim value of 10 as 11.
+ */
+void set_dumpable(struct mm_struct *mm, int value)
+{
+ switch (value) {
+ case 0:
+ clear_bit(MMF_DUMPABLE, &mm->flags);
+ smp_wmb();
+ clear_bit(MMF_DUMP_SECURELY, &mm->flags);
+ break;
+ case 1:
+ set_bit(MMF_DUMPABLE, &mm->flags);
+ smp_wmb();
+ clear_bit(MMF_DUMP_SECURELY, &mm->flags);
+ break;
+ case 2:
+ set_bit(MMF_DUMP_SECURELY, &mm->flags);
+ smp_wmb();
+ set_bit(MMF_DUMPABLE, &mm->flags);
+ break;
+ }
+}
+
+static int __get_dumpable(unsigned long mm_flags)
+{
+ int ret;
+
+ ret = mm_flags & MMF_DUMPABLE_MASK;
+ return (ret >= 2) ? 2 : ret;
+}
+
+/*
+ * This returns the actual value of the suid_dumpable flag. For things
+ * that are using this for checking for privilege transitions, it must
+ * test against SUID_DUMP_USER rather than treating it as a boolean
+ * value.
+ */
+int get_dumpable(struct mm_struct *mm)
+{
+ return __get_dumpable(mm->flags);
+}
+
+static void wait_for_dump_helpers(struct file *file)
+{
+ struct pipe_inode_info *pipe;
+
+ pipe = file->f_path.dentry->d_inode->i_pipe;
+
+ pipe_lock(pipe);
+ pipe->readers++;
+ pipe->writers--;
+
+ while ((pipe->readers > 1) && (!signal_pending(current))) {
+ wake_up_interruptible_sync(&pipe->wait);
+ kill_fasync(&pipe->fasync_readers, SIGIO, POLL_IN);
+ pipe_wait(pipe);
+ }
+
+ pipe->readers--;
+ pipe->writers++;
+ pipe_unlock(pipe);
+
+}
+
+
+/*
+ * umh_pipe_setup
+ * helper function to customize the process used
+ * to collect the core in userspace. Specifically
+ * it sets up a pipe and installs it as fd 0 (stdin)
+ * for the process. Returns 0 on success, or
+ * PTR_ERR on failure.
+ * Note that it also sets the core limit to 1. This
+ * is a special value that we use to trap recursive
+ * core dumps
+ */
+static int umh_pipe_setup(struct subprocess_info *info, struct cred *new)
+{
+ struct file *rp, *wp;
+ struct fdtable *fdt;
+ struct coredump_params *cp = (struct coredump_params *)info->data;
+ struct files_struct *cf = current->files;
+
+ wp = create_write_pipe(0);
+ if (IS_ERR(wp))
+ return PTR_ERR(wp);
+
+ rp = create_read_pipe(wp, 0);
+ if (IS_ERR(rp)) {
+ free_write_pipe(wp);
+ return PTR_ERR(rp);
+ }
+
+ cp->file = wp;
+
+ sys_close(0);
+ fd_install(0, rp);
+ spin_lock(&cf->file_lock);
+ fdt = files_fdtable(cf);
+ __set_open_fd(0, fdt);
+ __clear_close_on_exec(0, fdt);
+ spin_unlock(&cf->file_lock);
+
+ /* and disallow core files too */
+ current->signal->rlim[RLIMIT_CORE] = (struct rlimit){1, 1};
+
+ return 0;
+}
+
+#ifdef CONFIG_RAMDUMP
+/* ramdump entry */
+extern void ramdump_entry(void);
+int sysctl_ramdump_on_user = 1;
+#endif
+
+void do_coredump(long signr, int exit_code, struct pt_regs *regs)
+{
+ struct core_state core_state;
+ struct core_name cn;
+ struct mm_struct *mm = current->mm;
+ struct linux_binfmt * binfmt;
+ const struct cred *old_cred;
+ struct cred *cred;
+ int retval = 0;
+ int flag = 0;
+ int ispipe;
+ static atomic_t core_dump_count = ATOMIC_INIT(0);
+ struct coredump_params cprm = {
+ .signr = signr,
+ .regs = regs,
+ .limit = rlimit(RLIMIT_CORE),
+ /*
+ * We must use the same mm->flags while dumping core to avoid
+ * inconsistency of bit flags, since this flag is not protected
+ * by any locks.
+ */
+ .mm_flags = mm->flags,
+ };
+
+ audit_core_dumps(signr);
+
+ binfmt = mm->binfmt;
+ if (!binfmt || !binfmt->core_dump)
+ goto fail;
+ if (!__get_dumpable(cprm.mm_flags))
+ goto fail;
+
+ cred = prepare_creds();
+ if (!cred)
+ goto fail;
+ /*
+ * We cannot trust fsuid as being the "true" uid of the
+ * process nor do we know its entire history. We only know it
+ * was tainted so we dump it as root in mode 2.
+ */
+ if (__get_dumpable(cprm.mm_flags) == 2) {
+ /* Setuid core dump mode */
+ flag = O_EXCL; /* Stop rewrite attacks */
+ cred->fsuid = 0; /* Dump root private */
+ }
+
+ retval = coredump_wait(exit_code, &core_state);
+ if (retval < 0)
+ goto fail_creds;
+
+ old_cred = override_creds(cred);
+
+ /*
+ * Clear any false indication of pending signals that might
+ * be seen by the filesystem code called to write the core file.
+ */
+ clear_thread_flag(TIF_SIGPENDING);
+
+ ispipe = format_corename(&cn, signr);
+
+ if (ispipe) {
+ int dump_count;
+ char **helper_argv;
+
+ if (ispipe < 0) {
+ printk(KERN_WARNING "format_corename failed\n");
+ printk(KERN_WARNING "Aborting core\n");
+ goto fail_corename;
+ }
+
+ if (cprm.limit == 1) {
+ /*
+ * Normally core limits are irrelevant to pipes, since
+ * we're not writing to the file system, but we use
+ * cprm.limit of 1 here as a speacial value. Any
+ * non-1 limit gets set to RLIM_INFINITY below, but
+ * a limit of 0 skips the dump. This is a consistent
+ * way to catch recursive crashes. We can still crash
+ * if the core_pattern binary sets RLIM_CORE = !1
+ * but it runs as root, and can do lots of stupid things
+ * Note that we use task_tgid_vnr here to grab the pid
+ * of the process group leader. That way we get the
+ * right pid if a thread in a multi-threaded
+ * core_pattern process dies.
+ */
+ printk(KERN_WARNING
+ "Process %d(%s) has RLIMIT_CORE set to 1\n",
+ task_tgid_vnr(current), current->comm);
+ printk(KERN_WARNING "Aborting core\n");
+ goto fail_unlock;
+ }
+ cprm.limit = RLIM_INFINITY;
+
+ dump_count = atomic_inc_return(&core_dump_count);
+ if (core_pipe_limit && (core_pipe_limit < dump_count)) {
+ printk(KERN_WARNING "Pid %d(%s) over core_pipe_limit\n",
+ task_tgid_vnr(current), current->comm);
+ printk(KERN_WARNING "Skipping core dump\n");
+ goto fail_dropcount;
+ }
+
+ helper_argv = argv_split(GFP_KERNEL, cn.corename+1, NULL);
+ if (!helper_argv) {
+ printk(KERN_WARNING "%s failed to allocate memory\n",
+ __func__);
+ goto fail_dropcount;
+ }
+
+ retval = call_usermodehelper_fns(helper_argv[0], helper_argv,
+ NULL, UMH_WAIT_EXEC, umh_pipe_setup,
+ NULL, &cprm);
+ argv_free(helper_argv);
+ if (retval) {
+ printk(KERN_INFO "Core dump to %s pipe failed\n",
+ cn.corename);
+ goto close_fail;
+ }
+ } else {
+ struct inode *inode;
+
+ if (cprm.limit < binfmt->min_coredump)
+ goto fail_unlock;
+
+ cprm.file = filp_open(cn.corename,
+ O_CREAT | 2 | O_NOFOLLOW | O_LARGEFILE | flag,
+ 0600);
+ if (IS_ERR(cprm.file))
+ goto fail_unlock;
+
+ inode = cprm.file->f_path.dentry->d_inode;
+ if (inode->i_nlink > 1)
+ goto close_fail;
+ if (d_unhashed(cprm.file->f_path.dentry))
+ goto close_fail;
+ /*
+ * AK: actually i see no reason to not allow this for named
+ * pipes etc, but keep the previous behaviour for now.
+ */
+ if (!S_ISREG(inode->i_mode))
+ goto close_fail;
+ /*
+ * Dont allow local users get cute and trick others to coredump
+ * into their pre-created files.
+ */
+ if (inode->i_uid != current_fsuid())
+ goto close_fail;
+ if (!cprm.file->f_op || !cprm.file->f_op->write)
+ goto close_fail;
+ if (do_truncate(cprm.file->f_path.dentry, 0, 0, cprm.file))
+ goto close_fail;
+ }
+
+ retval = binfmt->core_dump(&cprm);
+ if (retval)
+ current->signal->group_exit_code |= 0x80;
+
+ if (ispipe && core_pipe_limit)
+ wait_for_dump_helpers(cprm.file);
+close_fail:
+ if (cprm.file)
+ filp_close(cprm.file, NULL);
+fail_dropcount:
+ if (ispipe)
+ atomic_dec(&core_dump_count);
+fail_unlock:
+ kfree(cn.corename);
+fail_corename:
+ coredump_finish(mm);
+ revert_creds(old_cred);
+fail_creds:
+ put_cred(cred);
+fail:
+ /*
+ * user ramdump entry
+ */
+#ifdef CONFIG_RAMDUMP
+ if(sysctl_ramdump_on_user)
+ panic("User ramdump enabled, user panic\n");//ramdump_entry();
+ else
+ printk("User ramdump disabled, current process is: %s, pid is %i!\n", current->comm, current->pid);
+#endif
+ return;
+}
+
+/*
+ * Core dumping helper functions. These are the only things you should
+ * do on a core-file: use only these functions to write out all the
+ * necessary info.
+ */
+int dump_write(struct file *file, const void *addr, int nr)
+{
+ return access_ok(VERIFY_READ, addr, nr) && file->f_op->write(file, addr, nr, &file->f_pos) == nr;
+}
+EXPORT_SYMBOL(dump_write);
+
+int dump_seek(struct file *file, loff_t off)
+{
+ int ret = 1;
+
+ if (file->f_op->llseek && file->f_op->llseek != no_llseek) {
+ if (file->f_op->llseek(file, off, SEEK_CUR) < 0)
+ return 0;
+ } else {
+ char *buf = (char *)get_zeroed_page(GFP_KERNEL);
+
+ if (!buf)
+ return 0;
+ while (off > 0) {
+ unsigned long n = off;
+
+ if (n > PAGE_SIZE)
+ n = PAGE_SIZE;
+ if (!dump_write(file, buf, n)) {
+ ret = 0;
+ break;
+ }
+ off -= n;
+ }
+ free_page((unsigned long)buf);
+ }
+ return ret;
+}
+EXPORT_SYMBOL(dump_seek);