/*- * Copyright (c) 2000 David O'Brien * Copyright (c) 1995-1996 Søren Schmidt * Copyright (c) 1996 Peter Wemm * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer * in this position and unchanged. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. The name of the author may not be used to endorse or promote products * derived from this software without specific prior written permission * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ #include __FBSDID("$FreeBSD$"); #include "opt_compat.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #if defined(COMPAT_IA32) && __ELF_WORD_SIZE == 32 #include #include #endif #define OLD_EI_BRAND 8 static int __elfN(check_header)(const Elf_Ehdr *hdr); static Elf_Brandinfo *__elfN(get_brandinfo)(const Elf_Ehdr *hdr, const char *interp); static int __elfN(load_file)(struct proc *p, const char *file, u_long *addr, u_long *entry, size_t pagesize); static int __elfN(load_section)(struct vmspace *vmspace, vm_object_t object, vm_offset_t offset, caddr_t vmaddr, size_t memsz, size_t filsz, vm_prot_t prot, size_t pagesize); static int __CONCAT(exec_, __elfN(imgact))(struct image_params *imgp); SYSCTL_NODE(_kern, OID_AUTO, __CONCAT(elf, __ELF_WORD_SIZE), CTLFLAG_RW, 0, ""); int __elfN(fallback_brand) = -1; SYSCTL_INT(__CONCAT(_kern_elf, __ELF_WORD_SIZE), OID_AUTO, fallback_brand, CTLFLAG_RW, &__elfN(fallback_brand), 0, __XSTRING(__CONCAT(ELF, __ELF_WORD_SIZE)) " brand of last resort"); TUNABLE_INT("kern.elf" __XSTRING(__ELF_WORD_SIZE) ".fallback_brand", &__elfN(fallback_brand)); static int elf_trace = 0; SYSCTL_INT(_debug, OID_AUTO, __elfN(trace), CTLFLAG_RW, &elf_trace, 0, ""); static int elf_legacy_coredump = 0; SYSCTL_INT(_debug, OID_AUTO, __elfN(legacy_coredump), CTLFLAG_RW, &elf_legacy_coredump, 0, ""); static Elf_Brandinfo *elf_brand_list[MAX_BRANDS]; #define trunc_page_ps(va, ps) ((va) & ~(ps - 1)) #define round_page_ps(va, ps) (((va) + (ps - 1)) & ~(ps - 1)) #define aligned(a, t) (trunc_page_ps((u_long)(a), sizeof(t)) == (u_long)(a)) int __elfN(insert_brand_entry)(Elf_Brandinfo *entry) { int i; for (i = 0; i < MAX_BRANDS; i++) { if (elf_brand_list[i] == NULL) { elf_brand_list[i] = entry; break; } } if (i == MAX_BRANDS) return (-1); return (0); } int __elfN(remove_brand_entry)(Elf_Brandinfo *entry) { int i; for (i = 0; i < MAX_BRANDS; i++) { if (elf_brand_list[i] == entry) { elf_brand_list[i] = NULL; break; } } if (i == MAX_BRANDS) return (-1); return (0); } int __elfN(brand_inuse)(Elf_Brandinfo *entry) { struct proc *p; int rval = FALSE; sx_slock(&allproc_lock); FOREACH_PROC_IN_SYSTEM(p) { if (p->p_sysent == entry->sysvec) { rval = TRUE; break; } } sx_sunlock(&allproc_lock); return (rval); } static Elf_Brandinfo * __elfN(get_brandinfo)(const Elf_Ehdr *hdr, const char *interp) { Elf_Brandinfo *bi; int i; /* * We support three types of branding -- (1) the ELF EI_OSABI field * that SCO added to the ELF spec, (2) FreeBSD 3.x's traditional string * branding w/in the ELF header, and (3) path of the `interp_path' * field. We should also look for an ".note.ABI-tag" ELF section now * in all Linux ELF binaries, FreeBSD 4.1+, and some NetBSD ones. */ /* If the executable has a brand, search for it in the brand list. */ for (i = 0; i < MAX_BRANDS; i++) { bi = elf_brand_list[i]; if (bi != NULL && hdr->e_machine == bi->machine && (hdr->e_ident[EI_OSABI] == bi->brand || strncmp((const char *)&hdr->e_ident[OLD_EI_BRAND], bi->compat_3_brand, strlen(bi->compat_3_brand)) == 0)) return (bi); } /* Lacking a known brand, search for a recognized interpreter. */ if (interp != NULL) { for (i = 0; i < MAX_BRANDS; i++) { bi = elf_brand_list[i]; if (bi != NULL && hdr->e_machine == bi->machine && strcmp(interp, bi->interp_path) == 0) return (bi); } } /* Lacking a recognized interpreter, try the default brand */ for (i = 0; i < MAX_BRANDS; i++) { bi = elf_brand_list[i]; if (bi != NULL && hdr->e_machine == bi->machine && __elfN(fallback_brand) == bi->brand) return (bi); } return (NULL); } static int __elfN(check_header)(const Elf_Ehdr *hdr) { Elf_Brandinfo *bi; int i; if (!IS_ELF(*hdr) || hdr->e_ident[EI_CLASS] != ELF_TARG_CLASS || hdr->e_ident[EI_DATA] != ELF_TARG_DATA || hdr->e_ident[EI_VERSION] != EV_CURRENT || hdr->e_phentsize != sizeof(Elf_Phdr) || hdr->e_version != ELF_TARG_VER) return (ENOEXEC); /* * Make sure we have at least one brand for this machine. */ for (i = 0; i < MAX_BRANDS; i++) { bi = elf_brand_list[i]; if (bi != NULL && bi->machine == hdr->e_machine) break; } if (i == MAX_BRANDS) return (ENOEXEC); return (0); } static int __elfN(map_partial)(vm_map_t map, vm_object_t object, vm_ooffset_t offset, vm_offset_t start, vm_offset_t end, vm_prot_t prot) { struct sf_buf *sf; int error; vm_offset_t off; /* * Create the page if it doesn't exist yet. Ignore errors. */ vm_map_lock(map); vm_map_insert(map, NULL, 0, trunc_page(start), round_page(end), VM_PROT_ALL, VM_PROT_ALL, 0); vm_map_unlock(map); /* * Find the page from the underlying object. */ if (object) { sf = vm_imgact_map_page(object, offset); if (sf == NULL) return (KERN_FAILURE); off = offset - trunc_page(offset); error = copyout((caddr_t)sf_buf_kva(sf) + off, (caddr_t)start, end - start); vm_imgact_unmap_page(sf); if (error) { return (KERN_FAILURE); } } return (KERN_SUCCESS); } static int __elfN(map_insert)(vm_map_t map, vm_object_t object, vm_ooffset_t offset, vm_offset_t start, vm_offset_t end, vm_prot_t prot, int cow) { struct sf_buf *sf; vm_offset_t off; vm_size_t sz; int error, rv; if (start != trunc_page(start)) { rv = __elfN(map_partial)(map, object, offset, start, round_page(start), prot); if (rv) return (rv); offset += round_page(start) - start; start = round_page(start); } if (end != round_page(end)) { rv = __elfN(map_partial)(map, object, offset + trunc_page(end) - start, trunc_page(end), end, prot); if (rv) return (rv); end = trunc_page(end); } if (end > start) { if (offset & PAGE_MASK) { /* * The mapping is not page aligned. This means we have * to copy the data. Sigh. */ rv = vm_map_find(map, NULL, 0, &start, end - start, FALSE, prot | VM_PROT_WRITE, VM_PROT_ALL, 0); if (rv) return (rv); if (object == NULL) return (KERN_SUCCESS); for (; start < end; start += sz) { sf = vm_imgact_map_page(object, offset); if (sf == NULL) return (KERN_FAILURE); off = offset - trunc_page(offset); sz = end - start; if (sz > PAGE_SIZE - off) sz = PAGE_SIZE - off; error = copyout((caddr_t)sf_buf_kva(sf) + off, (caddr_t)start, sz); vm_imgact_unmap_page(sf); if (error) { return (KERN_FAILURE); } offset += sz; } rv = KERN_SUCCESS; } else { vm_object_reference(object); vm_map_lock(map); rv = vm_map_insert(map, object, offset, start, end, prot, VM_PROT_ALL, cow); vm_map_unlock(map); if (rv != KERN_SUCCESS) vm_object_deallocate(object); } return (rv); } else { return (KERN_SUCCESS); } } static int __elfN(load_section)(struct vmspace *vmspace, vm_object_t object, vm_offset_t offset, caddr_t vmaddr, size_t memsz, size_t filsz, vm_prot_t prot, size_t pagesize) { struct sf_buf *sf; size_t map_len; vm_offset_t map_addr; int error, rv, cow; size_t copy_len; vm_offset_t file_addr; /* * It's necessary to fail if the filsz + offset taken from the * header is greater than the actual file pager object's size. * If we were to allow this, then the vm_map_find() below would * walk right off the end of the file object and into the ether. * * While I'm here, might as well check for something else that * is invalid: filsz cannot be greater than memsz. */ if ((off_t)filsz + offset > object->un_pager.vnp.vnp_size || filsz > memsz) { uprintf("elf_load_section: truncated ELF file\n"); return (ENOEXEC); } map_addr = trunc_page_ps((vm_offset_t)vmaddr, pagesize); file_addr = trunc_page_ps(offset, pagesize); /* * We have two choices. We can either clear the data in the last page * of an oversized mapping, or we can start the anon mapping a page * early and copy the initialized data into that first page. We * choose the second.. */ if (memsz > filsz) map_len = trunc_page_ps(offset + filsz, pagesize) - file_addr; else map_len = round_page_ps(offset + filsz, pagesize) - file_addr; if (map_len != 0) { /* cow flags: don't dump readonly sections in core */ cow = MAP_COPY_ON_WRITE | MAP_PREFAULT | (prot & VM_PROT_WRITE ? 0 : MAP_DISABLE_COREDUMP); rv = __elfN(map_insert)(&vmspace->vm_map, object, file_addr, /* file offset */ map_addr, /* virtual start */ map_addr + map_len,/* virtual end */ prot, cow); if (rv != KERN_SUCCESS) return (EINVAL); /* we can stop now if we've covered it all */ if (memsz == filsz) { return (0); } } /* * We have to get the remaining bit of the file into the first part * of the oversized map segment. This is normally because the .data * segment in the file is extended to provide bss. It's a neat idea * to try and save a page, but it's a pain in the behind to implement. */ copy_len = (offset + filsz) - trunc_page_ps(offset + filsz, pagesize); map_addr = trunc_page_ps((vm_offset_t)vmaddr + filsz, pagesize); map_len = round_page_ps((vm_offset_t)vmaddr + memsz, pagesize) - map_addr; /* This had damn well better be true! */ if (map_len != 0) { rv = __elfN(map_insert)(&vmspace->vm_map, NULL, 0, map_addr, map_addr + map_len, VM_PROT_ALL, 0); if (rv != KERN_SUCCESS) { return (EINVAL); } } if (copy_len != 0) { vm_offset_t off; sf = vm_imgact_map_page(object, offset + filsz); if (sf == NULL) return (EIO); /* send the page fragment to user space */ off = trunc_page_ps(offset + filsz, pagesize) - trunc_page(offset + filsz); error = copyout((caddr_t)sf_buf_kva(sf) + off, (caddr_t)map_addr, copy_len); vm_imgact_unmap_page(sf); if (error) { return (error); } } /* * set it to the specified protection. * XXX had better undo the damage from pasting over the cracks here! */ vm_map_protect(&vmspace->vm_map, trunc_page(map_addr), round_page(map_addr + map_len), prot, FALSE); return (0); } /* * Load the file "file" into memory. It may be either a shared object * or an executable. * * The "addr" reference parameter is in/out. On entry, it specifies * the address where a shared object should be loaded. If the file is * an executable, this value is ignored. On exit, "addr" specifies * where the file was actually loaded. * * The "entry" reference parameter is out only. On exit, it specifies * the entry point for the loaded file. */ static int __elfN(load_file)(struct proc *p, const char *file, u_long *addr, u_long *entry, size_t pagesize) { struct { struct nameidata nd; struct vattr attr; struct image_params image_params; } *tempdata; const Elf_Ehdr *hdr = NULL; const Elf_Phdr *phdr = NULL; struct nameidata *nd; struct vmspace *vmspace = p->p_vmspace; struct vattr *attr; struct image_params *imgp; vm_prot_t prot; u_long rbase; u_long base_addr = 0; int vfslocked, error, i, numsegs; if (curthread->td_proc != p) panic("elf_load_file - thread"); /* XXXKSE DIAGNOSTIC */ tempdata = malloc(sizeof(*tempdata), M_TEMP, M_WAITOK); nd = &tempdata->nd; attr = &tempdata->attr; imgp = &tempdata->image_params; /* * Initialize part of the common data */ imgp->proc = p; imgp->attr = attr; imgp->firstpage = NULL; imgp->image_header = NULL; imgp->object = NULL; imgp->execlabel = NULL; /* XXXKSE */ NDINIT(nd, LOOKUP, MPSAFE|LOCKLEAF|FOLLOW, UIO_SYSSPACE, file, curthread); vfslocked = 0; if ((error = namei(nd)) != 0) { nd->ni_vp = NULL; goto fail; } vfslocked = NDHASGIANT(nd); NDFREE(nd, NDF_ONLY_PNBUF); imgp->vp = nd->ni_vp; /* * Check permissions, modes, uid, etc on the file, and "open" it. */ error = exec_check_permissions(imgp); if (error) goto fail; error = exec_map_first_page(imgp); if (error) goto fail; /* * Also make certain that the interpreter stays the same, so set * its VV_TEXT flag, too. */ nd->ni_vp->v_vflag |= VV_TEXT; imgp->object = nd->ni_vp->v_object; hdr = (const Elf_Ehdr *)imgp->image_header; if ((error = __elfN(check_header)(hdr)) != 0) goto fail; if (hdr->e_type == ET_DYN) rbase = *addr; else if (hdr->e_type == ET_EXEC) rbase = 0; else { error = ENOEXEC; goto fail; } /* Only support headers that fit within first page for now */ /* (multiplication of two Elf_Half fields will not overflow) */ if ((hdr->e_phoff > PAGE_SIZE) || (hdr->e_phentsize * hdr->e_phnum) > PAGE_SIZE - hdr->e_phoff) { error = ENOEXEC; goto fail; } phdr = (const Elf_Phdr *)(imgp->image_header + hdr->e_phoff); if (!aligned(phdr, Elf_Addr)) { error = ENOEXEC; goto fail; } for (i = 0, numsegs = 0; i < hdr->e_phnum; i++) { if (phdr[i].p_type == PT_LOAD) { /* Loadable segment */ prot = 0; if (phdr[i].p_flags & PF_X) prot |= VM_PROT_EXECUTE; if (phdr[i].p_flags & PF_W) prot |= VM_PROT_WRITE; if (phdr[i].p_flags & PF_R) prot |= VM_PROT_READ; if ((error = __elfN(load_section)(vmspace, imgp->object, phdr[i].p_offset, (caddr_t)(uintptr_t)phdr[i].p_vaddr + rbase, phdr[i].p_memsz, phdr[i].p_filesz, prot, pagesize)) != 0) goto fail; /* * Establish the base address if this is the * first segment. */ if (numsegs == 0) base_addr = trunc_page(phdr[i].p_vaddr + rbase); numsegs++; } } *addr = base_addr; *entry = (unsigned long)hdr->e_entry + rbase; fail: if (imgp->firstpage) exec_unmap_first_page(imgp); if (nd->ni_vp) vput(nd->ni_vp); VFS_UNLOCK_GIANT(vfslocked); free(tempdata, M_TEMP); return (error); } static const char FREEBSD_ABI_VENDOR[] = "FreeBSD"; static int __CONCAT(exec_, __elfN(imgact))(struct image_params *imgp) { const Elf_Ehdr *hdr = (const Elf_Ehdr *)imgp->image_header; const Elf_Phdr *phdr, *pnote = NULL; Elf_Auxargs *elf_auxargs; struct vmspace *vmspace; vm_prot_t prot; u_long text_size = 0, data_size = 0, total_size = 0; u_long text_addr = 0, data_addr = 0; u_long seg_size, seg_addr; u_long addr, entry = 0, proghdr = 0; int error = 0, i; const char *interp = NULL, *newinterp = NULL; Elf_Brandinfo *brand_info; const Elf_Note *note, *note_end; char *path; const char *note_name; struct sysentvec *sv; /* * Do we have a valid ELF header ? * * Only allow ET_EXEC & ET_DYN here, reject ET_DYN later * if particular brand doesn't support it. */ if (__elfN(check_header)(hdr) != 0 || (hdr->e_type != ET_EXEC && hdr->e_type != ET_DYN)) return (-1); /* * From here on down, we return an errno, not -1, as we've * detected an ELF file. */ if ((hdr->e_phoff > PAGE_SIZE) || (hdr->e_phoff + hdr->e_phentsize * hdr->e_phnum) > PAGE_SIZE) { /* Only support headers in first page for now */ return (ENOEXEC); } phdr = (const Elf_Phdr *)(imgp->image_header + hdr->e_phoff); if (!aligned(phdr, Elf_Addr)) return (ENOEXEC); for (i = 0; i < hdr->e_phnum; i++) { if (phdr[i].p_type == PT_INTERP) { /* Path to interpreter */ if (phdr[i].p_filesz > MAXPATHLEN || phdr[i].p_offset + phdr[i].p_filesz > PAGE_SIZE) return (ENOEXEC); interp = imgp->image_header + phdr[i].p_offset; break; } } brand_info = __elfN(get_brandinfo)(hdr, interp); if (brand_info == NULL) { uprintf("ELF binary type \"%u\" not known.\n", hdr->e_ident[EI_OSABI]); return (ENOEXEC); } if (hdr->e_type == ET_DYN && (brand_info->flags & BI_CAN_EXEC_DYN) == 0) return (ENOEXEC); sv = brand_info->sysvec; if (interp != NULL && brand_info->interp_newpath != NULL) newinterp = brand_info->interp_newpath; /* * Avoid a possible deadlock if the current address space is destroyed * and that address space maps the locked vnode. In the common case, * the locked vnode's v_usecount is decremented but remains greater * than zero. Consequently, the vnode lock is not needed by vrele(). * However, in cases where the vnode lock is external, such as nullfs, * v_usecount may become zero. */ VOP_UNLOCK(imgp->vp, 0); error = exec_new_vmspace(imgp, sv); imgp->proc->p_sysent = sv; vn_lock(imgp->vp, LK_EXCLUSIVE | LK_RETRY); if (error) return (error); vmspace = imgp->proc->p_vmspace; for (i = 0; i < hdr->e_phnum; i++) { switch (phdr[i].p_type) { case PT_LOAD: /* Loadable segment */ prot = 0; if (phdr[i].p_flags & PF_X) prot |= VM_PROT_EXECUTE; if (phdr[i].p_flags & PF_W) prot |= VM_PROT_WRITE; if (phdr[i].p_flags & PF_R) prot |= VM_PROT_READ; #if defined(__ia64__) && __ELF_WORD_SIZE == 32 && defined(IA32_ME_HARDER) /* * Some x86 binaries assume read == executable, * notably the M3 runtime and therefore cvsup */ if (prot & VM_PROT_READ) prot |= VM_PROT_EXECUTE; #endif if ((error = __elfN(load_section)(vmspace, imgp->object, phdr[i].p_offset, (caddr_t)(uintptr_t)phdr[i].p_vaddr, phdr[i].p_memsz, phdr[i].p_filesz, prot, sv->sv_pagesize)) != 0) return (error); /* * If this segment contains the program headers, * remember their virtual address for the AT_PHDR * aux entry. Static binaries don't usually include * a PT_PHDR entry. */ if (phdr[i].p_offset == 0 && hdr->e_phoff + hdr->e_phnum * hdr->e_phentsize <= phdr[i].p_filesz) proghdr = phdr[i].p_vaddr + hdr->e_phoff; seg_addr = trunc_page(phdr[i].p_vaddr); seg_size = round_page(phdr[i].p_memsz + phdr[i].p_vaddr - seg_addr); /* * Is this .text or .data? We can't use * VM_PROT_WRITE or VM_PROT_EXEC, it breaks the * alpha terribly and possibly does other bad * things so we stick to the old way of figuring * it out: If the segment contains the program * entry point, it's a text segment, otherwise it * is a data segment. * * Note that obreak() assumes that data_addr + * data_size == end of data load area, and the ELF * file format expects segments to be sorted by * address. If multiple data segments exist, the * last one will be used. */ if (hdr->e_entry >= phdr[i].p_vaddr && hdr->e_entry < (phdr[i].p_vaddr + phdr[i].p_memsz)) { text_size = seg_size; text_addr = seg_addr; entry = (u_long)hdr->e_entry; } else { data_size = seg_size; data_addr = seg_addr; } total_size += seg_size; break; case PT_PHDR: /* Program header table info */ proghdr = phdr[i].p_vaddr; break; case PT_NOTE: pnote = &phdr[i]; break; default: break; } } if (data_addr == 0 && data_size == 0) { data_addr = text_addr; data_size = text_size; } /* * Check limits. It should be safe to check the * limits after loading the segments since we do * not actually fault in all the segments pages. */ PROC_LOCK(imgp->proc); if (data_size > lim_cur(imgp->proc, RLIMIT_DATA) || text_size > maxtsiz || total_size > lim_cur(imgp->proc, RLIMIT_VMEM)) { PROC_UNLOCK(imgp->proc); return (ENOMEM); } vmspace->vm_tsize = text_size >> PAGE_SHIFT; vmspace->vm_taddr = (caddr_t)(uintptr_t)text_addr; vmspace->vm_dsize = data_size >> PAGE_SHIFT; vmspace->vm_daddr = (caddr_t)(uintptr_t)data_addr; /* * We load the dynamic linker where a userland call * to mmap(0, ...) would put it. The rationale behind this * calculation is that it leaves room for the heap to grow to * its maximum allowed size. */ addr = round_page((vm_offset_t)imgp->proc->p_vmspace->vm_daddr + lim_max(imgp->proc, RLIMIT_DATA)); PROC_UNLOCK(imgp->proc); imgp->entry_addr = entry; if (interp != NULL) { int have_interp = FALSE; VOP_UNLOCK(imgp->vp, 0); if (brand_info->emul_path != NULL && brand_info->emul_path[0] != '\0') { path = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); snprintf(path, MAXPATHLEN, "%s%s", brand_info->emul_path, interp); error = __elfN(load_file)(imgp->proc, path, &addr, &imgp->entry_addr, sv->sv_pagesize); free(path, M_TEMP); if (error == 0) have_interp = TRUE; } if (!have_interp && newinterp != NULL) { error = __elfN(load_file)(imgp->proc, newinterp, &addr, &imgp->entry_addr, sv->sv_pagesize); have_interp = TRUE; } if (!have_interp) { error = __elfN(load_file)(imgp->proc, interp, &addr, &imgp->entry_addr, sv->sv_pagesize); } vn_lock(imgp->vp, LK_EXCLUSIVE | LK_RETRY); if (error != 0) { uprintf("ELF interpreter %s not found\n", interp); return (error); } } /* * Construct auxargs table (used by the fixup routine) */ elf_auxargs = malloc(sizeof(Elf_Auxargs), M_TEMP, M_WAITOK); elf_auxargs->execfd = -1; elf_auxargs->phdr = proghdr; elf_auxargs->phent = hdr->e_phentsize; elf_auxargs->phnum = hdr->e_phnum; elf_auxargs->pagesz = PAGE_SIZE; elf_auxargs->base = addr; elf_auxargs->flags = 0; elf_auxargs->entry = entry; elf_auxargs->trace = elf_trace; imgp->auxargs = elf_auxargs; imgp->interpreted = 0; /* * Try to fetch the osreldate for FreeBSD binary from the ELF * OSABI-note. Only the first page of the image is searched, * the same as for headers. */ if (pnote != NULL && pnote->p_offset < PAGE_SIZE && pnote->p_offset + pnote->p_filesz < PAGE_SIZE ) { note = (const Elf_Note *)(imgp->image_header + pnote->p_offset); if (!aligned(note, Elf32_Addr)) { free(imgp->auxargs, M_TEMP); imgp->auxargs = NULL; return (ENOEXEC); } note_end = (const Elf_Note *)(imgp->image_header + pnote->p_offset + pnote->p_filesz); while (note < note_end) { if (note->n_namesz == sizeof(FREEBSD_ABI_VENDOR) && note->n_descsz == sizeof(int32_t) && note->n_type == 1 /* ABI_NOTETYPE */) { note_name = (const char *)(note + 1); if (strncmp(FREEBSD_ABI_VENDOR, note_name, sizeof(FREEBSD_ABI_VENDOR)) == 0) { imgp->proc->p_osrel = *(const int32_t *) (note_name + round_page_ps(sizeof(FREEBSD_ABI_VENDOR), sizeof(Elf32_Addr))); break; } } note = (const Elf_Note *)((const char *)(note + 1) + round_page_ps(note->n_namesz, sizeof(Elf32_Addr)) + round_page_ps(note->n_descsz, sizeof(Elf32_Addr))); } } return (error); } #define suword __CONCAT(suword, __ELF_WORD_SIZE) int __elfN(freebsd_fixup)(register_t **stack_base, struct image_params *imgp) { Elf_Auxargs *args = (Elf_Auxargs *)imgp->auxargs; Elf_Addr *base; Elf_Addr *pos; base = (Elf_Addr *)*stack_base; pos = base + (imgp->args->argc + imgp->args->envc + 2); if (args->trace) { AUXARGS_ENTRY(pos, AT_DEBUG, 1); } if (args->execfd != -1) { AUXARGS_ENTRY(pos, AT_EXECFD, args->execfd); } AUXARGS_ENTRY(pos, AT_PHDR, args->phdr); AUXARGS_ENTRY(pos, AT_PHENT, args->phent); AUXARGS_ENTRY(pos, AT_PHNUM, args->phnum); AUXARGS_ENTRY(pos, AT_PAGESZ, args->pagesz); AUXARGS_ENTRY(pos, AT_FLAGS, args->flags); AUXARGS_ENTRY(pos, AT_ENTRY, args->entry); AUXARGS_ENTRY(pos, AT_BASE, args->base); AUXARGS_ENTRY(pos, AT_NULL, 0); free(imgp->auxargs, M_TEMP); imgp->auxargs = NULL; base--; suword(base, (long)imgp->args->argc); *stack_base = (register_t *)base; return (0); } /* * Code for generating ELF core dumps. */ typedef void (*segment_callback)(vm_map_entry_t, void *); /* Closure for cb_put_phdr(). */ struct phdr_closure { Elf_Phdr *phdr; /* Program header to fill in */ Elf_Off offset; /* Offset of segment in core file */ }; /* Closure for cb_size_segment(). */ struct sseg_closure { int count; /* Count of writable segments. */ size_t size; /* Total size of all writable segments. */ }; static void cb_put_phdr(vm_map_entry_t, void *); static void cb_size_segment(vm_map_entry_t, void *); static void each_writable_segment(struct thread *, segment_callback, void *); static int __elfN(corehdr)(struct thread *, struct vnode *, struct ucred *, int, void *, size_t); static void __elfN(puthdr)(struct thread *, void *, size_t *, int); static void __elfN(putnote)(void *, size_t *, const char *, int, const void *, size_t); int __elfN(coredump)(td, vp, limit) struct thread *td; struct vnode *vp; off_t limit; { struct ucred *cred = td->td_ucred; int error = 0; struct sseg_closure seginfo; void *hdr; size_t hdrsize; /* Size the program segments. */ seginfo.count = 0; seginfo.size = 0; each_writable_segment(td, cb_size_segment, &seginfo); /* * Calculate the size of the core file header area by making * a dry run of generating it. Nothing is written, but the * size is calculated. */ hdrsize = 0; __elfN(puthdr)(td, (void *)NULL, &hdrsize, seginfo.count); if (hdrsize + seginfo.size >= limit) return (EFAULT); /* * Allocate memory for building the header, fill it up, * and write it out. */ hdr = malloc(hdrsize, M_TEMP, M_WAITOK); if (hdr == NULL) { return (EINVAL); } error = __elfN(corehdr)(td, vp, cred, seginfo.count, hdr, hdrsize); /* Write the contents of all of the writable segments. */ if (error == 0) { Elf_Phdr *php; off_t offset; int i; php = (Elf_Phdr *)((char *)hdr + sizeof(Elf_Ehdr)) + 1; offset = hdrsize; for (i = 0; i < seginfo.count; i++) { error = vn_rdwr_inchunks(UIO_WRITE, vp, (caddr_t)(uintptr_t)php->p_vaddr, php->p_filesz, offset, UIO_USERSPACE, IO_UNIT | IO_DIRECT, cred, NOCRED, NULL, curthread); /* XXXKSE */ if (error != 0) break; offset += php->p_filesz; php++; } } free(hdr, M_TEMP); return (error); } /* * A callback for each_writable_segment() to write out the segment's * program header entry. */ static void cb_put_phdr(entry, closure) vm_map_entry_t entry; void *closure; { struct phdr_closure *phc = (struct phdr_closure *)closure; Elf_Phdr *phdr = phc->phdr; phc->offset = round_page(phc->offset); phdr->p_type = PT_LOAD; phdr->p_offset = phc->offset; phdr->p_vaddr = entry->start; phdr->p_paddr = 0; phdr->p_filesz = phdr->p_memsz = entry->end - entry->start; phdr->p_align = PAGE_SIZE; phdr->p_flags = 0; if (entry->protection & VM_PROT_READ) phdr->p_flags |= PF_R; if (entry->protection & VM_PROT_WRITE) phdr->p_flags |= PF_W; if (entry->protection & VM_PROT_EXECUTE) phdr->p_flags |= PF_X; phc->offset += phdr->p_filesz; phc->phdr++; } /* * A callback for each_writable_segment() to gather information about * the number of segments and their total size. */ static void cb_size_segment(entry, closure) vm_map_entry_t entry; void *closure; { struct sseg_closure *ssc = (struct sseg_closure *)closure; ssc->count++; ssc->size += entry->end - entry->start; } /* * For each writable segment in the process's memory map, call the given * function with a pointer to the map entry and some arbitrary * caller-supplied data. */ static void each_writable_segment(td, func, closure) struct thread *td; segment_callback func; void *closure; { struct proc *p = td->td_proc; vm_map_t map = &p->p_vmspace->vm_map; vm_map_entry_t entry; vm_object_t backing_object, object; boolean_t ignore_entry; vm_map_lock_read(map); for (entry = map->header.next; entry != &map->header; entry = entry->next) { /* * Don't dump inaccessible mappings, deal with legacy * coredump mode. * * Note that read-only segments related to the elf binary * are marked MAP_ENTRY_NOCOREDUMP now so we no longer * need to arbitrarily ignore such segments. */ if (elf_legacy_coredump) { if ((entry->protection & VM_PROT_RW) != VM_PROT_RW) continue; } else { if ((entry->protection & VM_PROT_ALL) == 0) continue; } /* * Dont include memory segment in the coredump if * MAP_NOCORE is set in mmap(2) or MADV_NOCORE in * madvise(2). Do not dump submaps (i.e. parts of the * kernel map). */ if (entry->eflags & (MAP_ENTRY_NOCOREDUMP|MAP_ENTRY_IS_SUB_MAP)) continue; if ((object = entry->object.vm_object) == NULL) continue; /* Ignore memory-mapped devices and such things. */ VM_OBJECT_LOCK(object); while ((backing_object = object->backing_object) != NULL) { VM_OBJECT_LOCK(backing_object); VM_OBJECT_UNLOCK(object); object = backing_object; } ignore_entry = object->type != OBJT_DEFAULT && object->type != OBJT_SWAP && object->type != OBJT_VNODE; VM_OBJECT_UNLOCK(object); if (ignore_entry) continue; (*func)(entry, closure); } vm_map_unlock_read(map); } /* * Write the core file header to the file, including padding up to * the page boundary. */ static int __elfN(corehdr)(td, vp, cred, numsegs, hdr, hdrsize) struct thread *td; struct vnode *vp; struct ucred *cred; int numsegs; size_t hdrsize; void *hdr; { size_t off; /* Fill in the header. */ bzero(hdr, hdrsize); off = 0; __elfN(puthdr)(td, hdr, &off, numsegs); /* Write it to the core file. */ return (vn_rdwr_inchunks(UIO_WRITE, vp, hdr, hdrsize, (off_t)0, UIO_SYSSPACE, IO_UNIT | IO_DIRECT, cred, NOCRED, NULL, td)); /* XXXKSE */ } #if defined(COMPAT_IA32) && __ELF_WORD_SIZE == 32 typedef struct prstatus32 elf_prstatus_t; typedef struct prpsinfo32 elf_prpsinfo_t; typedef struct fpreg32 elf_prfpregset_t; typedef struct fpreg32 elf_fpregset_t; typedef struct reg32 elf_gregset_t; #else typedef prstatus_t elf_prstatus_t; typedef prpsinfo_t elf_prpsinfo_t; typedef prfpregset_t elf_prfpregset_t; typedef prfpregset_t elf_fpregset_t; typedef gregset_t elf_gregset_t; #endif static void __elfN(puthdr)(struct thread *td, void *dst, size_t *off, int numsegs) { struct { elf_prstatus_t status; elf_prfpregset_t fpregset; elf_prpsinfo_t psinfo; } *tempdata; elf_prstatus_t *status; elf_prfpregset_t *fpregset; elf_prpsinfo_t *psinfo; struct proc *p; struct thread *thr; size_t ehoff, noteoff, notesz, phoff; p = td->td_proc; ehoff = *off; *off += sizeof(Elf_Ehdr); phoff = *off; *off += (numsegs + 1) * sizeof(Elf_Phdr); noteoff = *off; /* * Don't allocate space for the notes if we're just calculating * the size of the header. We also don't collect the data. */ if (dst != NULL) { tempdata = malloc(sizeof(*tempdata), M_TEMP, M_ZERO|M_WAITOK); status = &tempdata->status; fpregset = &tempdata->fpregset; psinfo = &tempdata->psinfo; } else { tempdata = NULL; status = NULL; fpregset = NULL; psinfo = NULL; } if (dst != NULL) { psinfo->pr_version = PRPSINFO_VERSION; psinfo->pr_psinfosz = sizeof(elf_prpsinfo_t); strlcpy(psinfo->pr_fname, td->td_name, sizeof(psinfo->pr_fname)); /* * XXX - We don't fill in the command line arguments properly * yet. */ strlcpy(psinfo->pr_psargs, td->td_name, sizeof(psinfo->pr_psargs)); } __elfN(putnote)(dst, off, "FreeBSD", NT_PRPSINFO, psinfo, sizeof *psinfo); /* * To have the debugger select the right thread (LWP) as the initial * thread, we dump the state of the thread passed to us in td first. * This is the thread that causes the core dump and thus likely to * be the right thread one wants to have selected in the debugger. */ thr = td; while (thr != NULL) { if (dst != NULL) { status->pr_version = PRSTATUS_VERSION; status->pr_statussz = sizeof(elf_prstatus_t); status->pr_gregsetsz = sizeof(elf_gregset_t); status->pr_fpregsetsz = sizeof(elf_fpregset_t); status->pr_osreldate = osreldate; status->pr_cursig = p->p_sig; status->pr_pid = thr->td_tid; #if defined(COMPAT_IA32) && __ELF_WORD_SIZE == 32 fill_regs32(thr, &status->pr_reg); fill_fpregs32(thr, fpregset); #else fill_regs(thr, &status->pr_reg); fill_fpregs(thr, fpregset); #endif } __elfN(putnote)(dst, off, "FreeBSD", NT_PRSTATUS, status, sizeof *status); __elfN(putnote)(dst, off, "FreeBSD", NT_FPREGSET, fpregset, sizeof *fpregset); /* * Allow for MD specific notes, as well as any MD * specific preparations for writing MI notes. */ __elfN(dump_thread)(thr, dst, off); thr = (thr == td) ? TAILQ_FIRST(&p->p_threads) : TAILQ_NEXT(thr, td_plist); if (thr == td) thr = TAILQ_NEXT(thr, td_plist); } notesz = *off - noteoff; if (dst != NULL) free(tempdata, M_TEMP); /* Align up to a page boundary for the program segments. */ *off = round_page(*off); if (dst != NULL) { Elf_Ehdr *ehdr; Elf_Phdr *phdr; struct phdr_closure phc; /* * Fill in the ELF header. */ ehdr = (Elf_Ehdr *)((char *)dst + ehoff); ehdr->e_ident[EI_MAG0] = ELFMAG0; ehdr->e_ident[EI_MAG1] = ELFMAG1; ehdr->e_ident[EI_MAG2] = ELFMAG2; ehdr->e_ident[EI_MAG3] = ELFMAG3; ehdr->e_ident[EI_CLASS] = ELF_CLASS; ehdr->e_ident[EI_DATA] = ELF_DATA; ehdr->e_ident[EI_VERSION] = EV_CURRENT; ehdr->e_ident[EI_OSABI] = ELFOSABI_FREEBSD; ehdr->e_ident[EI_ABIVERSION] = 0; ehdr->e_ident[EI_PAD] = 0; ehdr->e_type = ET_CORE; #if defined(COMPAT_IA32) && __ELF_WORD_SIZE == 32 ehdr->e_machine = EM_386; #else ehdr->e_machine = ELF_ARCH; #endif ehdr->e_version = EV_CURRENT; ehdr->e_entry = 0; ehdr->e_phoff = phoff; ehdr->e_flags = 0; ehdr->e_ehsize = sizeof(Elf_Ehdr); ehdr->e_phentsize = sizeof(Elf_Phdr); ehdr->e_phnum = numsegs + 1; ehdr->e_shentsize = sizeof(Elf_Shdr); ehdr->e_shnum = 0; ehdr->e_shstrndx = SHN_UNDEF; /* * Fill in the program header entries. */ phdr = (Elf_Phdr *)((char *)dst + phoff); /* The note segement. */ phdr->p_type = PT_NOTE; phdr->p_offset = noteoff; phdr->p_vaddr = 0; phdr->p_paddr = 0; phdr->p_filesz = notesz; phdr->p_memsz = 0; phdr->p_flags = 0; phdr->p_align = 0; phdr++; /* All the writable segments from the program. */ phc.phdr = phdr; phc.offset = *off; each_writable_segment(td, cb_put_phdr, &phc); } } static void __elfN(putnote)(void *dst, size_t *off, const char *name, int type, const void *desc, size_t descsz) { Elf_Note note; note.n_namesz = strlen(name) + 1; note.n_descsz = descsz; note.n_type = type; if (dst != NULL) bcopy(¬e, (char *)dst + *off, sizeof note); *off += sizeof note; if (dst != NULL) bcopy(name, (char *)dst + *off, note.n_namesz); *off += roundup2(note.n_namesz, sizeof(Elf_Size)); if (dst != NULL) bcopy(desc, (char *)dst + *off, note.n_descsz); *off += roundup2(note.n_descsz, sizeof(Elf_Size)); } /* * Tell kern_execve.c about it, with a little help from the linker. */ static struct execsw __elfN(execsw) = { __CONCAT(exec_, __elfN(imgact)), __XSTRING(__CONCAT(ELF, __ELF_WORD_SIZE)) }; EXEC_SET(__CONCAT(elf, __ELF_WORD_SIZE), __elfN(execsw));