1 // SPDX-License-Identifier: GPL-2.0-only
5 * Copyright (C) 1991, 1992 Linus Torvalds
9 * #!-checking implemented by tytso.
12 * Demand-loading implemented 01.12.91 - no need to read anything but
13 * the header into memory. The inode of the executable is put into
14 * "current->executable", and page faults do the actual loading. Clean.
16 * Once more I can proudly say that linux stood up to being changed: it
17 * was less than 2 hours work to get demand-loading completely implemented.
19 * Demand loading changed July 1993 by Eric Youngdale. Use mmap instead,
20 * current->executable is only used by the procfs. This allows a dispatch
21 * table to check for several different types of binary formats. We keep
22 * trying until we recognize the file or we run out of supported binary
26 #include <linux/kernel_read_file.h>
27 #include <linux/slab.h>
28 #include <linux/file.h>
29 #include <linux/fdtable.h>
31 #include <linux/vmacache.h>
32 #include <linux/stat.h>
33 #include <linux/fcntl.h>
34 #include <linux/swap.h>
35 #include <linux/string.h>
36 #include <linux/init.h>
37 #include <linux/sched/mm.h>
38 #include <linux/sched/coredump.h>
39 #include <linux/sched/signal.h>
40 #include <linux/sched/numa_balancing.h>
41 #include <linux/sched/task.h>
42 #include <linux/pagemap.h>
43 #include <linux/perf_event.h>
44 #include <linux/highmem.h>
45 #include <linux/spinlock.h>
46 #include <linux/key.h>
47 #include <linux/personality.h>
48 #include <linux/binfmts.h>
49 #include <linux/utsname.h>
50 #include <linux/pid_namespace.h>
51 #include <linux/module.h>
52 #include <linux/namei.h>
53 #include <linux/mount.h>
54 #include <linux/security.h>
55 #include <linux/syscalls.h>
56 #include <linux/tsacct_kern.h>
57 #include <linux/cn_proc.h>
58 #include <linux/audit.h>
59 #include <linux/tracehook.h>
60 #include <linux/kmod.h>
61 #include <linux/fsnotify.h>
62 #include <linux/fs_struct.h>
63 #include <linux/oom.h>
64 #include <linux/compat.h>
65 #include <linux/vmalloc.h>
66 #include <linux/io_uring.h>
67 #include <linux/syscall_user_dispatch.h>
69 #include <linux/uaccess.h>
70 #include <asm/mmu_context.h>
73 #include <trace/events/task.h>
76 #include <trace/events/sched.h>
78 static int bprm_creds_from_file(struct linux_binprm *bprm);
80 int suid_dumpable = 0;
82 static LIST_HEAD(formats);
83 static DEFINE_RWLOCK(binfmt_lock);
85 void __register_binfmt(struct linux_binfmt * fmt, int insert)
87 write_lock(&binfmt_lock);
88 insert ? list_add(&fmt->lh, &formats) :
89 list_add_tail(&fmt->lh, &formats);
90 write_unlock(&binfmt_lock);
93 EXPORT_SYMBOL(__register_binfmt);
95 void unregister_binfmt(struct linux_binfmt * fmt)
97 write_lock(&binfmt_lock);
99 write_unlock(&binfmt_lock);
102 EXPORT_SYMBOL(unregister_binfmt);
104 static inline void put_binfmt(struct linux_binfmt * fmt)
106 module_put(fmt->module);
109 bool path_noexec(const struct path *path)
111 return (path->mnt->mnt_flags & MNT_NOEXEC) ||
112 (path->mnt->mnt_sb->s_iflags & SB_I_NOEXEC);
117 * Note that a shared library must be both readable and executable due to
120 * Also note that we take the address to load from from the file itself.
122 SYSCALL_DEFINE1(uselib, const char __user *, library)
124 struct linux_binfmt *fmt;
126 struct filename *tmp = getname(library);
127 int error = PTR_ERR(tmp);
128 static const struct open_flags uselib_flags = {
129 .open_flag = O_LARGEFILE | O_RDONLY | __FMODE_EXEC,
130 .acc_mode = MAY_READ | MAY_EXEC,
131 .intent = LOOKUP_OPEN,
132 .lookup_flags = LOOKUP_FOLLOW,
138 file = do_filp_open(AT_FDCWD, tmp, &uselib_flags);
140 error = PTR_ERR(file);
145 * may_open() has already checked for this, so it should be
146 * impossible to trip now. But we need to be extra cautious
147 * and check again at the very end too.
150 if (WARN_ON_ONCE(!S_ISREG(file_inode(file)->i_mode) ||
151 path_noexec(&file->f_path)))
158 read_lock(&binfmt_lock);
159 list_for_each_entry(fmt, &formats, lh) {
160 if (!fmt->load_shlib)
162 if (!try_module_get(fmt->module))
164 read_unlock(&binfmt_lock);
165 error = fmt->load_shlib(file);
166 read_lock(&binfmt_lock);
168 if (error != -ENOEXEC)
171 read_unlock(&binfmt_lock);
177 #endif /* #ifdef CONFIG_USELIB */
181 * The nascent bprm->mm is not visible until exec_mmap() but it can
182 * use a lot of memory, account these pages in current->mm temporary
183 * for oom_badness()->get_mm_rss(). Once exec succeeds or fails, we
184 * change the counter back via acct_arg_size(0).
186 static void acct_arg_size(struct linux_binprm *bprm, unsigned long pages)
188 struct mm_struct *mm = current->mm;
189 long diff = (long)(pages - bprm->vma_pages);
194 bprm->vma_pages = pages;
195 add_mm_counter(mm, MM_ANONPAGES, diff);
198 static struct page *get_arg_page(struct linux_binprm *bprm, unsigned long pos,
203 unsigned int gup_flags = FOLL_FORCE;
205 #ifdef CONFIG_STACK_GROWSUP
207 ret = expand_downwards(bprm->vma, pos);
214 gup_flags |= FOLL_WRITE;
217 * We are doing an exec(). 'current' is the process
218 * doing the exec and bprm->mm is the new process's mm.
220 ret = get_user_pages_remote(bprm->mm, pos, 1, gup_flags,
226 acct_arg_size(bprm, vma_pages(bprm->vma));
231 static void put_arg_page(struct page *page)
236 static void free_arg_pages(struct linux_binprm *bprm)
240 static void flush_arg_page(struct linux_binprm *bprm, unsigned long pos,
243 flush_cache_page(bprm->vma, pos, page_to_pfn(page));
246 static int __bprm_mm_init(struct linux_binprm *bprm)
249 struct vm_area_struct *vma = NULL;
250 struct mm_struct *mm = bprm->mm;
252 bprm->vma = vma = vm_area_alloc(mm);
255 vma_set_anonymous(vma);
257 if (mmap_write_lock_killable(mm)) {
263 * Place the stack at the largest stack address the architecture
264 * supports. Later, we'll move this to an appropriate place. We don't
265 * use STACK_TOP because that can depend on attributes which aren't
268 BUILD_BUG_ON(VM_STACK_FLAGS & VM_STACK_INCOMPLETE_SETUP);
269 vma->vm_end = STACK_TOP_MAX;
270 vma->vm_start = vma->vm_end - PAGE_SIZE;
271 vma->vm_flags = VM_SOFTDIRTY | VM_STACK_FLAGS | VM_STACK_INCOMPLETE_SETUP;
272 vma->vm_page_prot = vm_get_page_prot(vma->vm_flags);
274 err = insert_vm_struct(mm, vma);
278 mm->stack_vm = mm->total_vm = 1;
279 mmap_write_unlock(mm);
280 bprm->p = vma->vm_end - sizeof(void *);
283 mmap_write_unlock(mm);
290 static bool valid_arg_len(struct linux_binprm *bprm, long len)
292 return len <= MAX_ARG_STRLEN;
297 static inline void acct_arg_size(struct linux_binprm *bprm, unsigned long pages)
301 static struct page *get_arg_page(struct linux_binprm *bprm, unsigned long pos,
306 page = bprm->page[pos / PAGE_SIZE];
307 if (!page && write) {
308 page = alloc_page(GFP_HIGHUSER|__GFP_ZERO);
311 bprm->page[pos / PAGE_SIZE] = page;
317 static void put_arg_page(struct page *page)
321 static void free_arg_page(struct linux_binprm *bprm, int i)
324 __free_page(bprm->page[i]);
325 bprm->page[i] = NULL;
329 static void free_arg_pages(struct linux_binprm *bprm)
333 for (i = 0; i < MAX_ARG_PAGES; i++)
334 free_arg_page(bprm, i);
337 static void flush_arg_page(struct linux_binprm *bprm, unsigned long pos,
342 static int __bprm_mm_init(struct linux_binprm *bprm)
344 bprm->p = PAGE_SIZE * MAX_ARG_PAGES - sizeof(void *);
348 static bool valid_arg_len(struct linux_binprm *bprm, long len)
350 return len <= bprm->p;
353 #endif /* CONFIG_MMU */
356 * Create a new mm_struct and populate it with a temporary stack
357 * vm_area_struct. We don't have enough context at this point to set the stack
358 * flags, permissions, and offset, so we use temporary values. We'll update
359 * them later in setup_arg_pages().
361 static int bprm_mm_init(struct linux_binprm *bprm)
364 struct mm_struct *mm = NULL;
366 bprm->mm = mm = mm_alloc();
371 /* Save current stack limit for all calculations made during exec. */
372 task_lock(current->group_leader);
373 bprm->rlim_stack = current->signal->rlim[RLIMIT_STACK];
374 task_unlock(current->group_leader);
376 err = __bprm_mm_init(bprm);
391 struct user_arg_ptr {
396 const char __user *const __user *native;
398 const compat_uptr_t __user *compat;
403 static const char __user *get_user_arg_ptr(struct user_arg_ptr argv, int nr)
405 const char __user *native;
408 if (unlikely(argv.is_compat)) {
409 compat_uptr_t compat;
411 if (get_user(compat, argv.ptr.compat + nr))
412 return ERR_PTR(-EFAULT);
414 return compat_ptr(compat);
418 if (get_user(native, argv.ptr.native + nr))
419 return ERR_PTR(-EFAULT);
425 * count() counts the number of strings in array ARGV.
427 static int count(struct user_arg_ptr argv, int max)
431 if (argv.ptr.native != NULL) {
433 const char __user *p = get_user_arg_ptr(argv, i);
445 if (fatal_signal_pending(current))
446 return -ERESTARTNOHAND;
453 static int count_strings_kernel(const char *const *argv)
460 for (i = 0; argv[i]; ++i) {
461 if (i >= MAX_ARG_STRINGS)
463 if (fatal_signal_pending(current))
464 return -ERESTARTNOHAND;
470 static int bprm_stack_limits(struct linux_binprm *bprm)
472 unsigned long limit, ptr_size;
475 * Limit to 1/4 of the max stack size or 3/4 of _STK_LIM
476 * (whichever is smaller) for the argv+env strings.
478 * - the remaining binfmt code will not run out of stack space,
479 * - the program will have a reasonable amount of stack left
482 limit = _STK_LIM / 4 * 3;
483 limit = min(limit, bprm->rlim_stack.rlim_cur / 4);
485 * We've historically supported up to 32 pages (ARG_MAX)
486 * of argument strings even with small stacks
488 limit = max_t(unsigned long, limit, ARG_MAX);
490 * We must account for the size of all the argv and envp pointers to
491 * the argv and envp strings, since they will also take up space in
492 * the stack. They aren't stored until much later when we can't
493 * signal to the parent that the child has run out of stack space.
494 * Instead, calculate it here so it's possible to fail gracefully.
496 ptr_size = (bprm->argc + bprm->envc) * sizeof(void *);
497 if (limit <= ptr_size)
501 bprm->argmin = bprm->p - limit;
506 * 'copy_strings()' copies argument/environment strings from the old
507 * processes's memory to the new process's stack. The call to get_user_pages()
508 * ensures the destination page is created and not swapped out.
510 static int copy_strings(int argc, struct user_arg_ptr argv,
511 struct linux_binprm *bprm)
513 struct page *kmapped_page = NULL;
515 unsigned long kpos = 0;
519 const char __user *str;
524 str = get_user_arg_ptr(argv, argc);
528 len = strnlen_user(str, MAX_ARG_STRLEN);
533 if (!valid_arg_len(bprm, len))
536 /* We're going to work our way backwords. */
541 if (bprm->p < bprm->argmin)
546 int offset, bytes_to_copy;
548 if (fatal_signal_pending(current)) {
549 ret = -ERESTARTNOHAND;
554 offset = pos % PAGE_SIZE;
558 bytes_to_copy = offset;
559 if (bytes_to_copy > len)
562 offset -= bytes_to_copy;
563 pos -= bytes_to_copy;
564 str -= bytes_to_copy;
565 len -= bytes_to_copy;
567 if (!kmapped_page || kpos != (pos & PAGE_MASK)) {
570 page = get_arg_page(bprm, pos, 1);
577 flush_kernel_dcache_page(kmapped_page);
578 kunmap(kmapped_page);
579 put_arg_page(kmapped_page);
582 kaddr = kmap(kmapped_page);
583 kpos = pos & PAGE_MASK;
584 flush_arg_page(bprm, kpos, kmapped_page);
586 if (copy_from_user(kaddr+offset, str, bytes_to_copy)) {
595 flush_kernel_dcache_page(kmapped_page);
596 kunmap(kmapped_page);
597 put_arg_page(kmapped_page);
603 * Copy and argument/environment string from the kernel to the processes stack.
605 int copy_string_kernel(const char *arg, struct linux_binprm *bprm)
607 int len = strnlen(arg, MAX_ARG_STRLEN) + 1 /* terminating NUL */;
608 unsigned long pos = bprm->p;
612 if (!valid_arg_len(bprm, len))
615 /* We're going to work our way backwards. */
618 if (IS_ENABLED(CONFIG_MMU) && bprm->p < bprm->argmin)
622 unsigned int bytes_to_copy = min_t(unsigned int, len,
623 min_not_zero(offset_in_page(pos), PAGE_SIZE));
627 pos -= bytes_to_copy;
628 arg -= bytes_to_copy;
629 len -= bytes_to_copy;
631 page = get_arg_page(bprm, pos, 1);
634 kaddr = kmap_atomic(page);
635 flush_arg_page(bprm, pos & PAGE_MASK, page);
636 memcpy(kaddr + offset_in_page(pos), arg, bytes_to_copy);
637 flush_kernel_dcache_page(page);
638 kunmap_atomic(kaddr);
644 EXPORT_SYMBOL(copy_string_kernel);
646 static int copy_strings_kernel(int argc, const char *const *argv,
647 struct linux_binprm *bprm)
650 int ret = copy_string_kernel(argv[argc], bprm);
653 if (fatal_signal_pending(current))
654 return -ERESTARTNOHAND;
663 * During bprm_mm_init(), we create a temporary stack at STACK_TOP_MAX. Once
664 * the binfmt code determines where the new stack should reside, we shift it to
665 * its final location. The process proceeds as follows:
667 * 1) Use shift to calculate the new vma endpoints.
668 * 2) Extend vma to cover both the old and new ranges. This ensures the
669 * arguments passed to subsequent functions are consistent.
670 * 3) Move vma's page tables to the new range.
671 * 4) Free up any cleared pgd range.
672 * 5) Shrink the vma to cover only the new range.
674 static int shift_arg_pages(struct vm_area_struct *vma, unsigned long shift)
676 struct mm_struct *mm = vma->vm_mm;
677 unsigned long old_start = vma->vm_start;
678 unsigned long old_end = vma->vm_end;
679 unsigned long length = old_end - old_start;
680 unsigned long new_start = old_start - shift;
681 unsigned long new_end = old_end - shift;
682 struct mmu_gather tlb;
684 BUG_ON(new_start > new_end);
687 * ensure there are no vmas between where we want to go
690 if (vma != find_vma(mm, new_start))
694 * cover the whole range: [new_start, old_end)
696 if (vma_adjust(vma, new_start, old_end, vma->vm_pgoff, NULL))
700 * move the page tables downwards, on failure we rely on
701 * process cleanup to remove whatever mess we made.
703 if (length != move_page_tables(vma, old_start,
704 vma, new_start, length, false))
708 tlb_gather_mmu(&tlb, mm);
709 if (new_end > old_start) {
711 * when the old and new regions overlap clear from new_end.
713 free_pgd_range(&tlb, new_end, old_end, new_end,
714 vma->vm_next ? vma->vm_next->vm_start : USER_PGTABLES_CEILING);
717 * otherwise, clean from old_start; this is done to not touch
718 * the address space in [new_end, old_start) some architectures
719 * have constraints on va-space that make this illegal (IA64) -
720 * for the others its just a little faster.
722 free_pgd_range(&tlb, old_start, old_end, new_end,
723 vma->vm_next ? vma->vm_next->vm_start : USER_PGTABLES_CEILING);
725 tlb_finish_mmu(&tlb);
728 * Shrink the vma to just the new range. Always succeeds.
730 vma_adjust(vma, new_start, new_end, vma->vm_pgoff, NULL);
736 * Finalizes the stack vm_area_struct. The flags and permissions are updated,
737 * the stack is optionally relocated, and some extra space is added.
739 int setup_arg_pages(struct linux_binprm *bprm,
740 unsigned long stack_top,
741 int executable_stack)
744 unsigned long stack_shift;
745 struct mm_struct *mm = current->mm;
746 struct vm_area_struct *vma = bprm->vma;
747 struct vm_area_struct *prev = NULL;
748 unsigned long vm_flags;
749 unsigned long stack_base;
750 unsigned long stack_size;
751 unsigned long stack_expand;
752 unsigned long rlim_stack;
754 #ifdef CONFIG_STACK_GROWSUP
755 /* Limit stack size */
756 stack_base = bprm->rlim_stack.rlim_max;
758 stack_base = calc_max_stack_size(stack_base);
760 /* Add space for stack randomization. */
761 stack_base += (STACK_RND_MASK << PAGE_SHIFT);
763 /* Make sure we didn't let the argument array grow too large. */
764 if (vma->vm_end - vma->vm_start > stack_base)
767 stack_base = PAGE_ALIGN(stack_top - stack_base);
769 stack_shift = vma->vm_start - stack_base;
770 mm->arg_start = bprm->p - stack_shift;
771 bprm->p = vma->vm_end - stack_shift;
773 stack_top = arch_align_stack(stack_top);
774 stack_top = PAGE_ALIGN(stack_top);
776 if (unlikely(stack_top < mmap_min_addr) ||
777 unlikely(vma->vm_end - vma->vm_start >= stack_top - mmap_min_addr))
780 stack_shift = vma->vm_end - stack_top;
782 bprm->p -= stack_shift;
783 mm->arg_start = bprm->p;
787 bprm->loader -= stack_shift;
788 bprm->exec -= stack_shift;
790 if (mmap_write_lock_killable(mm))
793 vm_flags = VM_STACK_FLAGS;
796 * Adjust stack execute permissions; explicitly enable for
797 * EXSTACK_ENABLE_X, disable for EXSTACK_DISABLE_X and leave alone
798 * (arch default) otherwise.
800 if (unlikely(executable_stack == EXSTACK_ENABLE_X))
802 else if (executable_stack == EXSTACK_DISABLE_X)
803 vm_flags &= ~VM_EXEC;
804 vm_flags |= mm->def_flags;
805 vm_flags |= VM_STACK_INCOMPLETE_SETUP;
807 ret = mprotect_fixup(vma, &prev, vma->vm_start, vma->vm_end,
813 if (unlikely(vm_flags & VM_EXEC)) {
814 pr_warn_once("process '%pD4' started with executable stack\n",
818 /* Move stack pages down in memory. */
820 ret = shift_arg_pages(vma, stack_shift);
825 /* mprotect_fixup is overkill to remove the temporary stack flags */
826 vma->vm_flags &= ~VM_STACK_INCOMPLETE_SETUP;
828 stack_expand = 131072UL; /* randomly 32*4k (or 2*64k) pages */
829 stack_size = vma->vm_end - vma->vm_start;
831 * Align this down to a page boundary as expand_stack
834 rlim_stack = bprm->rlim_stack.rlim_cur & PAGE_MASK;
835 #ifdef CONFIG_STACK_GROWSUP
836 if (stack_size + stack_expand > rlim_stack)
837 stack_base = vma->vm_start + rlim_stack;
839 stack_base = vma->vm_end + stack_expand;
841 if (stack_size + stack_expand > rlim_stack)
842 stack_base = vma->vm_end - rlim_stack;
844 stack_base = vma->vm_start - stack_expand;
846 current->mm->start_stack = bprm->p;
847 ret = expand_stack(vma, stack_base);
852 mmap_write_unlock(mm);
855 EXPORT_SYMBOL(setup_arg_pages);
860 * Transfer the program arguments and environment from the holding pages
861 * onto the stack. The provided stack pointer is adjusted accordingly.
863 int transfer_args_to_stack(struct linux_binprm *bprm,
864 unsigned long *sp_location)
866 unsigned long index, stop, sp;
869 stop = bprm->p >> PAGE_SHIFT;
872 for (index = MAX_ARG_PAGES - 1; index >= stop; index--) {
873 unsigned int offset = index == stop ? bprm->p & ~PAGE_MASK : 0;
874 char *src = kmap(bprm->page[index]) + offset;
875 sp -= PAGE_SIZE - offset;
876 if (copy_to_user((void *) sp, src, PAGE_SIZE - offset) != 0)
878 kunmap(bprm->page[index]);
888 EXPORT_SYMBOL(transfer_args_to_stack);
890 #endif /* CONFIG_MMU */
892 static struct file *do_open_execat(int fd, struct filename *name, int flags)
896 struct open_flags open_exec_flags = {
897 .open_flag = O_LARGEFILE | O_RDONLY | __FMODE_EXEC,
898 .acc_mode = MAY_EXEC,
899 .intent = LOOKUP_OPEN,
900 .lookup_flags = LOOKUP_FOLLOW,
903 if ((flags & ~(AT_SYMLINK_NOFOLLOW | AT_EMPTY_PATH)) != 0)
904 return ERR_PTR(-EINVAL);
905 if (flags & AT_SYMLINK_NOFOLLOW)
906 open_exec_flags.lookup_flags &= ~LOOKUP_FOLLOW;
907 if (flags & AT_EMPTY_PATH)
908 open_exec_flags.lookup_flags |= LOOKUP_EMPTY;
910 file = do_filp_open(fd, name, &open_exec_flags);
915 * may_open() has already checked for this, so it should be
916 * impossible to trip now. But we need to be extra cautious
917 * and check again at the very end too.
920 if (WARN_ON_ONCE(!S_ISREG(file_inode(file)->i_mode) ||
921 path_noexec(&file->f_path)))
924 err = deny_write_access(file);
928 if (name->name[0] != '\0')
939 struct file *open_exec(const char *name)
941 struct filename *filename = getname_kernel(name);
942 struct file *f = ERR_CAST(filename);
944 if (!IS_ERR(filename)) {
945 f = do_open_execat(AT_FDCWD, filename, 0);
950 EXPORT_SYMBOL(open_exec);
952 #if defined(CONFIG_HAVE_AOUT) || defined(CONFIG_BINFMT_FLAT) || \
953 defined(CONFIG_BINFMT_ELF_FDPIC)
954 ssize_t read_code(struct file *file, unsigned long addr, loff_t pos, size_t len)
956 ssize_t res = vfs_read(file, (void __user *)addr, len, &pos);
958 flush_icache_user_range(addr, addr + len);
961 EXPORT_SYMBOL(read_code);
965 * Maps the mm_struct mm into the current task struct.
966 * On success, this function returns with exec_update_lock
969 static int exec_mmap(struct mm_struct *mm)
971 struct task_struct *tsk;
972 struct mm_struct *old_mm, *active_mm;
975 /* Notify parent that we're no longer interested in the old VM */
977 old_mm = current->mm;
978 exec_mm_release(tsk, old_mm);
982 ret = down_write_killable(&tsk->signal->exec_update_lock);
988 * Make sure that if there is a core dump in progress
989 * for the old mm, we get out and die instead of going
990 * through with the exec. We must hold mmap_lock around
991 * checking core_state and changing tsk->mm.
993 mmap_read_lock(old_mm);
994 if (unlikely(old_mm->core_state)) {
995 mmap_read_unlock(old_mm);
996 up_write(&tsk->signal->exec_update_lock);
1002 membarrier_exec_mmap(mm);
1004 local_irq_disable();
1005 active_mm = tsk->active_mm;
1006 tsk->active_mm = mm;
1009 * This prevents preemption while active_mm is being loaded and
1010 * it and mm are being updated, which could cause problems for
1011 * lazy tlb mm refcounting when these are updated by context
1012 * switches. Not all architectures can handle irqs off over
1015 if (!IS_ENABLED(CONFIG_ARCH_WANT_IRQS_OFF_ACTIVATE_MM))
1017 activate_mm(active_mm, mm);
1018 if (IS_ENABLED(CONFIG_ARCH_WANT_IRQS_OFF_ACTIVATE_MM))
1020 tsk->mm->vmacache_seqnum = 0;
1021 vmacache_flush(tsk);
1024 mmap_read_unlock(old_mm);
1025 BUG_ON(active_mm != old_mm);
1026 setmax_mm_hiwater_rss(&tsk->signal->maxrss, old_mm);
1027 mm_update_next_owner(old_mm);
1035 static int de_thread(struct task_struct *tsk)
1037 struct signal_struct *sig = tsk->signal;
1038 struct sighand_struct *oldsighand = tsk->sighand;
1039 spinlock_t *lock = &oldsighand->siglock;
1041 if (thread_group_empty(tsk))
1042 goto no_thread_group;
1045 * Kill all other threads in the thread group.
1047 spin_lock_irq(lock);
1048 if (signal_group_exit(sig)) {
1050 * Another group action in progress, just
1051 * return so that the signal is processed.
1053 spin_unlock_irq(lock);
1057 sig->group_exit_task = tsk;
1058 sig->notify_count = zap_other_threads(tsk);
1059 if (!thread_group_leader(tsk))
1060 sig->notify_count--;
1062 while (sig->notify_count) {
1063 __set_current_state(TASK_KILLABLE);
1064 spin_unlock_irq(lock);
1066 if (__fatal_signal_pending(tsk))
1068 spin_lock_irq(lock);
1070 spin_unlock_irq(lock);
1073 * At this point all other threads have exited, all we have to
1074 * do is to wait for the thread group leader to become inactive,
1075 * and to assume its PID:
1077 if (!thread_group_leader(tsk)) {
1078 struct task_struct *leader = tsk->group_leader;
1081 cgroup_threadgroup_change_begin(tsk);
1082 write_lock_irq(&tasklist_lock);
1084 * Do this under tasklist_lock to ensure that
1085 * exit_notify() can't miss ->group_exit_task
1087 sig->notify_count = -1;
1088 if (likely(leader->exit_state))
1090 __set_current_state(TASK_KILLABLE);
1091 write_unlock_irq(&tasklist_lock);
1092 cgroup_threadgroup_change_end(tsk);
1094 if (__fatal_signal_pending(tsk))
1099 * The only record we have of the real-time age of a
1100 * process, regardless of execs it's done, is start_time.
1101 * All the past CPU time is accumulated in signal_struct
1102 * from sister threads now dead. But in this non-leader
1103 * exec, nothing survives from the original leader thread,
1104 * whose birth marks the true age of this process now.
1105 * When we take on its identity by switching to its PID, we
1106 * also take its birthdate (always earlier than our own).
1108 tsk->start_time = leader->start_time;
1109 tsk->start_boottime = leader->start_boottime;
1111 BUG_ON(!same_thread_group(leader, tsk));
1113 * An exec() starts a new thread group with the
1114 * TGID of the previous thread group. Rehash the
1115 * two threads with a switched PID, and release
1116 * the former thread group leader:
1119 /* Become a process group leader with the old leader's pid.
1120 * The old leader becomes a thread of the this thread group.
1122 exchange_tids(tsk, leader);
1123 transfer_pid(leader, tsk, PIDTYPE_TGID);
1124 transfer_pid(leader, tsk, PIDTYPE_PGID);
1125 transfer_pid(leader, tsk, PIDTYPE_SID);
1127 list_replace_rcu(&leader->tasks, &tsk->tasks);
1128 list_replace_init(&leader->sibling, &tsk->sibling);
1130 tsk->group_leader = tsk;
1131 leader->group_leader = tsk;
1133 tsk->exit_signal = SIGCHLD;
1134 leader->exit_signal = -1;
1136 BUG_ON(leader->exit_state != EXIT_ZOMBIE);
1137 leader->exit_state = EXIT_DEAD;
1140 * We are going to release_task()->ptrace_unlink() silently,
1141 * the tracer can sleep in do_wait(). EXIT_DEAD guarantees
1142 * the tracer wont't block again waiting for this thread.
1144 if (unlikely(leader->ptrace))
1145 __wake_up_parent(leader, leader->parent);
1146 write_unlock_irq(&tasklist_lock);
1147 cgroup_threadgroup_change_end(tsk);
1149 release_task(leader);
1152 sig->group_exit_task = NULL;
1153 sig->notify_count = 0;
1156 /* we have changed execution domain */
1157 tsk->exit_signal = SIGCHLD;
1159 BUG_ON(!thread_group_leader(tsk));
1163 /* protects against exit_notify() and __exit_signal() */
1164 read_lock(&tasklist_lock);
1165 sig->group_exit_task = NULL;
1166 sig->notify_count = 0;
1167 read_unlock(&tasklist_lock);
1173 * This function makes sure the current process has its own signal table,
1174 * so that flush_signal_handlers can later reset the handlers without
1175 * disturbing other processes. (Other processes might share the signal
1176 * table via the CLONE_SIGHAND option to clone().)
1178 static int unshare_sighand(struct task_struct *me)
1180 struct sighand_struct *oldsighand = me->sighand;
1182 if (refcount_read(&oldsighand->count) != 1) {
1183 struct sighand_struct *newsighand;
1185 * This ->sighand is shared with the CLONE_SIGHAND
1186 * but not CLONE_THREAD task, switch to the new one.
1188 newsighand = kmem_cache_alloc(sighand_cachep, GFP_KERNEL);
1192 refcount_set(&newsighand->count, 1);
1193 memcpy(newsighand->action, oldsighand->action,
1194 sizeof(newsighand->action));
1196 write_lock_irq(&tasklist_lock);
1197 spin_lock(&oldsighand->siglock);
1198 rcu_assign_pointer(me->sighand, newsighand);
1199 spin_unlock(&oldsighand->siglock);
1200 write_unlock_irq(&tasklist_lock);
1202 __cleanup_sighand(oldsighand);
1207 char *__get_task_comm(char *buf, size_t buf_size, struct task_struct *tsk)
1210 strncpy(buf, tsk->comm, buf_size);
1214 EXPORT_SYMBOL_GPL(__get_task_comm);
1217 * These functions flushes out all traces of the currently running executable
1218 * so that a new one can be started
1221 void __set_task_comm(struct task_struct *tsk, const char *buf, bool exec)
1224 trace_task_rename(tsk, buf);
1225 strlcpy(tsk->comm, buf, sizeof(tsk->comm));
1227 perf_event_comm(tsk, exec);
1231 * Calling this is the point of no return. None of the failures will be
1232 * seen by userspace since either the process is already taking a fatal
1233 * signal (via de_thread() or coredump), or will have SEGV raised
1234 * (after exec_mmap()) by search_binary_handler (see below).
1236 int begin_new_exec(struct linux_binprm * bprm)
1238 struct task_struct *me = current;
1241 /* Once we are committed compute the creds */
1242 retval = bprm_creds_from_file(bprm);
1247 * Ensure all future errors are fatal.
1249 bprm->point_of_no_return = true;
1252 * Make this the only thread in the thread group.
1254 retval = de_thread(me);
1259 * Cancel any io_uring activity across execve
1261 io_uring_task_cancel();
1263 /* Ensure the files table is not shared. */
1264 retval = unshare_files();
1269 * Must be called _before_ exec_mmap() as bprm->mm is
1270 * not visibile until then. This also enables the update
1273 set_mm_exe_file(bprm->mm, bprm->file);
1275 /* If the binary is not readable then enforce mm->dumpable=0 */
1276 would_dump(bprm, bprm->file);
1277 if (bprm->have_execfd)
1278 would_dump(bprm, bprm->executable);
1281 * Release all of the old mmap stuff
1283 acct_arg_size(bprm, 0);
1284 retval = exec_mmap(bprm->mm);
1290 #ifdef CONFIG_POSIX_TIMERS
1291 exit_itimers(me->signal);
1292 flush_itimer_signals();
1296 * Make the signal table private.
1298 retval = unshare_sighand(me);
1303 * Ensure that the uaccess routines can actually operate on userspace
1306 force_uaccess_begin();
1308 me->flags &= ~(PF_RANDOMIZE | PF_FORKNOEXEC | PF_KTHREAD |
1309 PF_NOFREEZE | PF_NO_SETAFFINITY);
1311 me->personality &= ~bprm->per_clear;
1313 clear_syscall_work_syscall_user_dispatch(me);
1316 * We have to apply CLOEXEC before we change whether the process is
1317 * dumpable (in setup_new_exec) to avoid a race with a process in userspace
1318 * trying to access the should-be-closed file descriptors of a process
1319 * undergoing exec(2).
1321 do_close_on_exec(me->files);
1323 if (bprm->secureexec) {
1324 /* Make sure parent cannot signal privileged process. */
1325 me->pdeath_signal = 0;
1328 * For secureexec, reset the stack limit to sane default to
1329 * avoid bad behavior from the prior rlimits. This has to
1330 * happen before arch_pick_mmap_layout(), which examines
1331 * RLIMIT_STACK, but after the point of no return to avoid
1332 * needing to clean up the change on failure.
1334 if (bprm->rlim_stack.rlim_cur > _STK_LIM)
1335 bprm->rlim_stack.rlim_cur = _STK_LIM;
1338 me->sas_ss_sp = me->sas_ss_size = 0;
1341 * Figure out dumpability. Note that this checking only of current
1342 * is wrong, but userspace depends on it. This should be testing
1343 * bprm->secureexec instead.
1345 if (bprm->interp_flags & BINPRM_FLAGS_ENFORCE_NONDUMP ||
1346 !(uid_eq(current_euid(), current_uid()) &&
1347 gid_eq(current_egid(), current_gid())))
1348 set_dumpable(current->mm, suid_dumpable);
1350 set_dumpable(current->mm, SUID_DUMP_USER);
1353 __set_task_comm(me, kbasename(bprm->filename), true);
1355 /* An exec changes our domain. We are no longer part of the thread
1357 WRITE_ONCE(me->self_exec_id, me->self_exec_id + 1);
1358 flush_signal_handlers(me, 0);
1360 retval = set_cred_ucounts(bprm->cred);
1365 * install the new credentials for this executable
1367 security_bprm_committing_creds(bprm);
1369 commit_creds(bprm->cred);
1373 * Disable monitoring for regular users
1374 * when executing setuid binaries. Must
1375 * wait until new credentials are committed
1376 * by commit_creds() above
1378 if (get_dumpable(me->mm) != SUID_DUMP_USER)
1379 perf_event_exit_task(me);
1381 * cred_guard_mutex must be held at least to this point to prevent
1382 * ptrace_attach() from altering our determination of the task's
1383 * credentials; any time after this it may be unlocked.
1385 security_bprm_committed_creds(bprm);
1387 /* Pass the opened binary to the interpreter. */
1388 if (bprm->have_execfd) {
1389 retval = get_unused_fd_flags(0);
1392 fd_install(retval, bprm->executable);
1393 bprm->executable = NULL;
1394 bprm->execfd = retval;
1399 up_write(&me->signal->exec_update_lock);
1403 EXPORT_SYMBOL(begin_new_exec);
1405 void would_dump(struct linux_binprm *bprm, struct file *file)
1407 struct inode *inode = file_inode(file);
1408 struct user_namespace *mnt_userns = file_mnt_user_ns(file);
1409 if (inode_permission(mnt_userns, inode, MAY_READ) < 0) {
1410 struct user_namespace *old, *user_ns;
1411 bprm->interp_flags |= BINPRM_FLAGS_ENFORCE_NONDUMP;
1413 /* Ensure mm->user_ns contains the executable */
1414 user_ns = old = bprm->mm->user_ns;
1415 while ((user_ns != &init_user_ns) &&
1416 !privileged_wrt_inode_uidgid(user_ns, mnt_userns, inode))
1417 user_ns = user_ns->parent;
1419 if (old != user_ns) {
1420 bprm->mm->user_ns = get_user_ns(user_ns);
1425 EXPORT_SYMBOL(would_dump);
1427 void setup_new_exec(struct linux_binprm * bprm)
1429 /* Setup things that can depend upon the personality */
1430 struct task_struct *me = current;
1432 arch_pick_mmap_layout(me->mm, &bprm->rlim_stack);
1434 arch_setup_new_exec();
1436 /* Set the new mm task size. We have to do that late because it may
1437 * depend on TIF_32BIT which is only updated in flush_thread() on
1438 * some architectures like powerpc
1440 me->mm->task_size = TASK_SIZE;
1441 up_write(&me->signal->exec_update_lock);
1442 mutex_unlock(&me->signal->cred_guard_mutex);
1444 EXPORT_SYMBOL(setup_new_exec);
1446 /* Runs immediately before start_thread() takes over. */
1447 void finalize_exec(struct linux_binprm *bprm)
1449 /* Store any stack rlimit changes before starting thread. */
1450 task_lock(current->group_leader);
1451 current->signal->rlim[RLIMIT_STACK] = bprm->rlim_stack;
1452 task_unlock(current->group_leader);
1454 EXPORT_SYMBOL(finalize_exec);
1457 * Prepare credentials and lock ->cred_guard_mutex.
1458 * setup_new_exec() commits the new creds and drops the lock.
1459 * Or, if exec fails before, free_bprm() should release ->cred
1462 static int prepare_bprm_creds(struct linux_binprm *bprm)
1464 if (mutex_lock_interruptible(¤t->signal->cred_guard_mutex))
1465 return -ERESTARTNOINTR;
1467 bprm->cred = prepare_exec_creds();
1468 if (likely(bprm->cred))
1471 mutex_unlock(¤t->signal->cred_guard_mutex);
1475 static void free_bprm(struct linux_binprm *bprm)
1478 acct_arg_size(bprm, 0);
1481 free_arg_pages(bprm);
1483 mutex_unlock(¤t->signal->cred_guard_mutex);
1484 abort_creds(bprm->cred);
1487 allow_write_access(bprm->file);
1490 if (bprm->executable)
1491 fput(bprm->executable);
1492 /* If a binfmt changed the interp, free it. */
1493 if (bprm->interp != bprm->filename)
1494 kfree(bprm->interp);
1495 kfree(bprm->fdpath);
1499 static struct linux_binprm *alloc_bprm(int fd, struct filename *filename)
1501 struct linux_binprm *bprm = kzalloc(sizeof(*bprm), GFP_KERNEL);
1502 int retval = -ENOMEM;
1506 if (fd == AT_FDCWD || filename->name[0] == '/') {
1507 bprm->filename = filename->name;
1509 if (filename->name[0] == '\0')
1510 bprm->fdpath = kasprintf(GFP_KERNEL, "/dev/fd/%d", fd);
1512 bprm->fdpath = kasprintf(GFP_KERNEL, "/dev/fd/%d/%s",
1513 fd, filename->name);
1517 bprm->filename = bprm->fdpath;
1519 bprm->interp = bprm->filename;
1521 retval = bprm_mm_init(bprm);
1529 return ERR_PTR(retval);
1532 int bprm_change_interp(const char *interp, struct linux_binprm *bprm)
1534 /* If a binfmt changed the interp, free it first. */
1535 if (bprm->interp != bprm->filename)
1536 kfree(bprm->interp);
1537 bprm->interp = kstrdup(interp, GFP_KERNEL);
1542 EXPORT_SYMBOL(bprm_change_interp);
1545 * determine how safe it is to execute the proposed program
1546 * - the caller must hold ->cred_guard_mutex to protect against
1547 * PTRACE_ATTACH or seccomp thread-sync
1549 static void check_unsafe_exec(struct linux_binprm *bprm)
1551 struct task_struct *p = current, *t;
1555 bprm->unsafe |= LSM_UNSAFE_PTRACE;
1558 * This isn't strictly necessary, but it makes it harder for LSMs to
1561 if (task_no_new_privs(current))
1562 bprm->unsafe |= LSM_UNSAFE_NO_NEW_PRIVS;
1566 spin_lock(&p->fs->lock);
1568 while_each_thread(p, t) {
1574 if (p->fs->users > n_fs)
1575 bprm->unsafe |= LSM_UNSAFE_SHARE;
1578 spin_unlock(&p->fs->lock);
1581 static void bprm_fill_uid(struct linux_binprm *bprm, struct file *file)
1583 /* Handle suid and sgid on files */
1584 struct user_namespace *mnt_userns;
1585 struct inode *inode;
1590 if (!mnt_may_suid(file->f_path.mnt))
1593 if (task_no_new_privs(current))
1596 inode = file->f_path.dentry->d_inode;
1597 mode = READ_ONCE(inode->i_mode);
1598 if (!(mode & (S_ISUID|S_ISGID)))
1601 mnt_userns = file_mnt_user_ns(file);
1603 /* Be careful if suid/sgid is set */
1606 /* reload atomically mode/uid/gid now that lock held */
1607 mode = inode->i_mode;
1608 uid = i_uid_into_mnt(mnt_userns, inode);
1609 gid = i_gid_into_mnt(mnt_userns, inode);
1610 inode_unlock(inode);
1612 /* We ignore suid/sgid if there are no mappings for them in the ns */
1613 if (!kuid_has_mapping(bprm->cred->user_ns, uid) ||
1614 !kgid_has_mapping(bprm->cred->user_ns, gid))
1617 if (mode & S_ISUID) {
1618 bprm->per_clear |= PER_CLEAR_ON_SETID;
1619 bprm->cred->euid = uid;
1622 if ((mode & (S_ISGID | S_IXGRP)) == (S_ISGID | S_IXGRP)) {
1623 bprm->per_clear |= PER_CLEAR_ON_SETID;
1624 bprm->cred->egid = gid;
1629 * Compute brpm->cred based upon the final binary.
1631 static int bprm_creds_from_file(struct linux_binprm *bprm)
1633 /* Compute creds based on which file? */
1634 struct file *file = bprm->execfd_creds ? bprm->executable : bprm->file;
1636 bprm_fill_uid(bprm, file);
1637 return security_bprm_creds_from_file(bprm, file);
1641 * Fill the binprm structure from the inode.
1642 * Read the first BINPRM_BUF_SIZE bytes
1644 * This may be called multiple times for binary chains (scripts for example).
1646 static int prepare_binprm(struct linux_binprm *bprm)
1650 memset(bprm->buf, 0, BINPRM_BUF_SIZE);
1651 return kernel_read(bprm->file, bprm->buf, BINPRM_BUF_SIZE, &pos);
1655 * Arguments are '\0' separated strings found at the location bprm->p
1656 * points to; chop off the first by relocating brpm->p to right after
1657 * the first '\0' encountered.
1659 int remove_arg_zero(struct linux_binprm *bprm)
1662 unsigned long offset;
1670 offset = bprm->p & ~PAGE_MASK;
1671 page = get_arg_page(bprm, bprm->p, 0);
1676 kaddr = kmap_atomic(page);
1678 for (; offset < PAGE_SIZE && kaddr[offset];
1679 offset++, bprm->p++)
1682 kunmap_atomic(kaddr);
1684 } while (offset == PAGE_SIZE);
1693 EXPORT_SYMBOL(remove_arg_zero);
1695 #define printable(c) (((c)=='\t') || ((c)=='\n') || (0x20<=(c) && (c)<=0x7e))
1697 * cycle the list of binary formats handler, until one recognizes the image
1699 static int search_binary_handler(struct linux_binprm *bprm)
1701 bool need_retry = IS_ENABLED(CONFIG_MODULES);
1702 struct linux_binfmt *fmt;
1705 retval = prepare_binprm(bprm);
1709 retval = security_bprm_check(bprm);
1715 read_lock(&binfmt_lock);
1716 list_for_each_entry(fmt, &formats, lh) {
1717 if (!try_module_get(fmt->module))
1719 read_unlock(&binfmt_lock);
1721 retval = fmt->load_binary(bprm);
1723 read_lock(&binfmt_lock);
1725 if (bprm->point_of_no_return || (retval != -ENOEXEC)) {
1726 read_unlock(&binfmt_lock);
1730 read_unlock(&binfmt_lock);
1733 if (printable(bprm->buf[0]) && printable(bprm->buf[1]) &&
1734 printable(bprm->buf[2]) && printable(bprm->buf[3]))
1736 if (request_module("binfmt-%04x", *(ushort *)(bprm->buf + 2)) < 0)
1745 static int exec_binprm(struct linux_binprm *bprm)
1747 pid_t old_pid, old_vpid;
1750 /* Need to fetch pid before load_binary changes it */
1751 old_pid = current->pid;
1753 old_vpid = task_pid_nr_ns(current, task_active_pid_ns(current->parent));
1756 /* This allows 4 levels of binfmt rewrites before failing hard. */
1757 for (depth = 0;; depth++) {
1762 ret = search_binary_handler(bprm);
1765 if (!bprm->interpreter)
1769 bprm->file = bprm->interpreter;
1770 bprm->interpreter = NULL;
1772 allow_write_access(exec);
1773 if (unlikely(bprm->have_execfd)) {
1774 if (bprm->executable) {
1778 bprm->executable = exec;
1784 trace_sched_process_exec(current, old_pid, bprm);
1785 ptrace_event(PTRACE_EVENT_EXEC, old_vpid);
1786 proc_exec_connector(current);
1791 * sys_execve() executes a new program.
1793 static int bprm_execve(struct linux_binprm *bprm,
1794 int fd, struct filename *filename, int flags)
1799 retval = prepare_bprm_creds(bprm);
1803 check_unsafe_exec(bprm);
1804 current->in_execve = 1;
1806 file = do_open_execat(fd, filename, flags);
1807 retval = PTR_ERR(file);
1815 * Record that a name derived from an O_CLOEXEC fd will be
1816 * inaccessible after exec. This allows the code in exec to
1817 * choose to fail when the executable is not mmaped into the
1818 * interpreter and an open file descriptor is not passed to
1819 * the interpreter. This makes for a better user experience
1820 * than having the interpreter start and then immediately fail
1821 * when it finds the executable is inaccessible.
1823 if (bprm->fdpath && get_close_on_exec(fd))
1824 bprm->interp_flags |= BINPRM_FLAGS_PATH_INACCESSIBLE;
1826 /* Set the unchanging part of bprm->cred */
1827 retval = security_bprm_creds_for_exec(bprm);
1831 retval = exec_binprm(bprm);
1835 /* execve succeeded */
1836 current->fs->in_exec = 0;
1837 current->in_execve = 0;
1838 rseq_execve(current);
1839 acct_update_integrals(current);
1840 task_numa_free(current, false);
1845 * If past the point of no return ensure the code never
1846 * returns to the userspace process. Use an existing fatal
1847 * signal if present otherwise terminate the process with
1850 if (bprm->point_of_no_return && !fatal_signal_pending(current))
1851 force_sigsegv(SIGSEGV);
1854 current->fs->in_exec = 0;
1855 current->in_execve = 0;
1860 static int do_execveat_common(int fd, struct filename *filename,
1861 struct user_arg_ptr argv,
1862 struct user_arg_ptr envp,
1865 struct linux_binprm *bprm;
1868 if (IS_ERR(filename))
1869 return PTR_ERR(filename);
1872 * We move the actual failure in case of RLIMIT_NPROC excess from
1873 * set*uid() to execve() because too many poorly written programs
1874 * don't check setuid() return code. Here we additionally recheck
1875 * whether NPROC limit is still exceeded.
1877 if ((current->flags & PF_NPROC_EXCEEDED) &&
1878 is_ucounts_overlimit(current_ucounts(), UCOUNT_RLIMIT_NPROC, rlimit(RLIMIT_NPROC))) {
1883 /* We're below the limit (still or again), so we don't want to make
1884 * further execve() calls fail. */
1885 current->flags &= ~PF_NPROC_EXCEEDED;
1887 bprm = alloc_bprm(fd, filename);
1889 retval = PTR_ERR(bprm);
1893 retval = count(argv, MAX_ARG_STRINGS);
1896 bprm->argc = retval;
1898 retval = count(envp, MAX_ARG_STRINGS);
1901 bprm->envc = retval;
1903 retval = bprm_stack_limits(bprm);
1907 retval = copy_string_kernel(bprm->filename, bprm);
1910 bprm->exec = bprm->p;
1912 retval = copy_strings(bprm->envc, envp, bprm);
1916 retval = copy_strings(bprm->argc, argv, bprm);
1920 retval = bprm_execve(bprm, fd, filename, flags);
1929 int kernel_execve(const char *kernel_filename,
1930 const char *const *argv, const char *const *envp)
1932 struct filename *filename;
1933 struct linux_binprm *bprm;
1937 filename = getname_kernel(kernel_filename);
1938 if (IS_ERR(filename))
1939 return PTR_ERR(filename);
1941 bprm = alloc_bprm(fd, filename);
1943 retval = PTR_ERR(bprm);
1947 retval = count_strings_kernel(argv);
1950 bprm->argc = retval;
1952 retval = count_strings_kernel(envp);
1955 bprm->envc = retval;
1957 retval = bprm_stack_limits(bprm);
1961 retval = copy_string_kernel(bprm->filename, bprm);
1964 bprm->exec = bprm->p;
1966 retval = copy_strings_kernel(bprm->envc, envp, bprm);
1970 retval = copy_strings_kernel(bprm->argc, argv, bprm);
1974 retval = bprm_execve(bprm, fd, filename, 0);
1982 static int do_execve(struct filename *filename,
1983 const char __user *const __user *__argv,
1984 const char __user *const __user *__envp)
1986 struct user_arg_ptr argv = { .ptr.native = __argv };
1987 struct user_arg_ptr envp = { .ptr.native = __envp };
1988 return do_execveat_common(AT_FDCWD, filename, argv, envp, 0);
1991 static int do_execveat(int fd, struct filename *filename,
1992 const char __user *const __user *__argv,
1993 const char __user *const __user *__envp,
1996 struct user_arg_ptr argv = { .ptr.native = __argv };
1997 struct user_arg_ptr envp = { .ptr.native = __envp };
1999 return do_execveat_common(fd, filename, argv, envp, flags);
2002 #ifdef CONFIG_COMPAT
2003 static int compat_do_execve(struct filename *filename,
2004 const compat_uptr_t __user *__argv,
2005 const compat_uptr_t __user *__envp)
2007 struct user_arg_ptr argv = {
2009 .ptr.compat = __argv,
2011 struct user_arg_ptr envp = {
2013 .ptr.compat = __envp,
2015 return do_execveat_common(AT_FDCWD, filename, argv, envp, 0);
2018 static int compat_do_execveat(int fd, struct filename *filename,
2019 const compat_uptr_t __user *__argv,
2020 const compat_uptr_t __user *__envp,
2023 struct user_arg_ptr argv = {
2025 .ptr.compat = __argv,
2027 struct user_arg_ptr envp = {
2029 .ptr.compat = __envp,
2031 return do_execveat_common(fd, filename, argv, envp, flags);
2035 void set_binfmt(struct linux_binfmt *new)
2037 struct mm_struct *mm = current->mm;
2040 module_put(mm->binfmt->module);
2044 __module_get(new->module);
2046 EXPORT_SYMBOL(set_binfmt);
2049 * set_dumpable stores three-value SUID_DUMP_* into mm->flags.
2051 void set_dumpable(struct mm_struct *mm, int value)
2053 if (WARN_ON((unsigned)value > SUID_DUMP_ROOT))
2056 set_mask_bits(&mm->flags, MMF_DUMPABLE_MASK, value);
2059 SYSCALL_DEFINE3(execve,
2060 const char __user *, filename,
2061 const char __user *const __user *, argv,
2062 const char __user *const __user *, envp)
2064 return do_execve(getname(filename), argv, envp);
2067 SYSCALL_DEFINE5(execveat,
2068 int, fd, const char __user *, filename,
2069 const char __user *const __user *, argv,
2070 const char __user *const __user *, envp,
2073 int lookup_flags = (flags & AT_EMPTY_PATH) ? LOOKUP_EMPTY : 0;
2075 return do_execveat(fd,
2076 getname_flags(filename, lookup_flags, NULL),
2080 #ifdef CONFIG_COMPAT
2081 COMPAT_SYSCALL_DEFINE3(execve, const char __user *, filename,
2082 const compat_uptr_t __user *, argv,
2083 const compat_uptr_t __user *, envp)
2085 return compat_do_execve(getname(filename), argv, envp);
2088 COMPAT_SYSCALL_DEFINE5(execveat, int, fd,
2089 const char __user *, filename,
2090 const compat_uptr_t __user *, argv,
2091 const compat_uptr_t __user *, envp,
2094 int lookup_flags = (flags & AT_EMPTY_PATH) ? LOOKUP_EMPTY : 0;
2096 return compat_do_execveat(fd,
2097 getname_flags(filename, lookup_flags, NULL),