diff options
author | Renato Botelho <renato@netgate.com> | 2016-01-13 17:56:30 -0200 |
---|---|---|
committer | Renato Botelho <renato@netgate.com> | 2016-01-13 17:56:30 -0200 |
commit | 3e0bf52f358eb969d165c4b1e54942ee94cf2c8d (patch) | |
tree | 440bb9907871a5bc578d65b32f0c4aa339096175 /sys/compat/linux/linux_vdso.c | |
parent | 4b4ac714f11471e43f18410bcc86da8f9dc3b88c (diff) | |
parent | e357bdb742b2696dcb81404917b6247f9e840232 (diff) | |
download | FreeBSD-src-3e0bf52f358eb969d165c4b1e54942ee94cf2c8d.zip FreeBSD-src-3e0bf52f358eb969d165c4b1e54942ee94cf2c8d.tar.gz |
Merge remote-tracking branch 'origin/stable/10' into devel
Diffstat (limited to 'sys/compat/linux/linux_vdso.c')
-rw-r--r-- | sys/compat/linux/linux_vdso.c | 244 |
1 files changed, 244 insertions, 0 deletions
diff --git a/sys/compat/linux/linux_vdso.c b/sys/compat/linux/linux_vdso.c new file mode 100644 index 0000000..5ab0ee6 --- /dev/null +++ b/sys/compat/linux/linux_vdso.c @@ -0,0 +1,244 @@ +/*- + * Copyright (c) 2013 Dmitry Chagin + * 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. + * + * 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 <sys/cdefs.h> +__FBSDID("$FreeBSD$"); + +#include "opt_compat.h" + +#if defined(__i386__) || (defined(__amd64__) && defined(COMPAT_LINUX32)) +#define __ELF_WORD_SIZE 32 +#else +#define __ELF_WORD_SIZE 64 +#endif + +#include <sys/param.h> +#include <sys/systm.h> +#include <sys/elf.h> +#include <sys/kernel.h> +#include <sys/lock.h> +#include <sys/rwlock.h> +#include <sys/queue.h> +#include <sys/sysent.h> + +#include <vm/vm.h> +#include <vm/vm_param.h> +#include <vm/pmap.h> +#include <vm/vm_extern.h> +#include <vm/vm_kern.h> +#include <vm/vm_map.h> +#include <vm/vm_object.h> +#include <vm/vm_page.h> +#include <vm/vm_pager.h> + +#include <compat/linux/linux_vdso.h> + +SLIST_HEAD(, linux_vdso_sym) __elfN(linux_vdso_syms) = + SLIST_HEAD_INITIALIZER(__elfN(linux_vdso_syms)); + +static int __elfN(symtabindex); +static int __elfN(symstrindex); + +static void +__elfN(linux_vdso_lookup)(Elf_Ehdr *, struct linux_vdso_sym *); + + +void +__elfN(linux_vdso_sym_init)(struct linux_vdso_sym *s) +{ + + SLIST_INSERT_HEAD(&__elfN(linux_vdso_syms), s, sym); +} + +vm_object_t +__elfN(linux_shared_page_init)(char **mapping) +{ + vm_page_t m; + vm_object_t obj; + vm_offset_t addr; + + obj = vm_pager_allocate(OBJT_PHYS, 0, PAGE_SIZE, + VM_PROT_DEFAULT, 0, NULL); + VM_OBJECT_WLOCK(obj); + m = vm_page_grab(obj, 0, VM_ALLOC_NOBUSY | VM_ALLOC_ZERO); + m->valid = VM_PAGE_BITS_ALL; + VM_OBJECT_WUNLOCK(obj); + addr = kva_alloc(PAGE_SIZE); + pmap_qenter(addr, &m, 1); + *mapping = (char *)addr; + return (obj); +} + +void +__elfN(linux_shared_page_fini)(vm_object_t obj) +{ + + vm_object_deallocate(obj); +} + +void +__elfN(linux_vdso_fixup)(struct sysentvec *sv) +{ + Elf_Ehdr *ehdr; + Elf_Shdr *shdr; + int i; + + ehdr = (Elf_Ehdr *) sv->sv_sigcode; + + if (!IS_ELF(*ehdr) || + ehdr->e_ident[EI_CLASS] != ELF_TARG_CLASS || + ehdr->e_ident[EI_DATA] != ELF_TARG_DATA || + ehdr->e_ident[EI_VERSION] != EV_CURRENT || + ehdr->e_shoff == 0 || + ehdr->e_shentsize != sizeof(Elf_Shdr)) + panic("Linux invalid vdso header.\n"); + + if (ehdr->e_type != ET_DYN) + panic("Linux invalid vdso header.\n"); + + shdr = (Elf_Shdr *) ((caddr_t)ehdr + ehdr->e_shoff); + + __elfN(symtabindex) = -1; + __elfN(symstrindex) = -1; + for (i = 0; i < ehdr->e_shnum; i++) { + if (shdr[i].sh_size == 0) + continue; + if (shdr[i].sh_type == SHT_DYNSYM) { + __elfN(symtabindex) = i; + __elfN(symstrindex) = shdr[i].sh_link; + } + } + + if (__elfN(symtabindex) == -1 || __elfN(symstrindex) == -1) + panic("Linux invalid vdso header.\n"); + + ehdr->e_ident[EI_OSABI] = ELFOSABI_LINUX; +} + +void +__elfN(linux_vdso_reloc)(struct sysentvec *sv, long vdso_adjust) +{ + struct linux_vdso_sym *lsym; + Elf_Ehdr *ehdr; + Elf_Phdr *phdr; + Elf_Shdr *shdr; + Elf_Dyn *dyn; + Elf_Sym *sym; + int i, symcnt; + + ehdr = (Elf_Ehdr *) sv->sv_sigcode; + + /* Adjust our so relative to the sigcode_base */ + if (vdso_adjust != 0) { + ehdr->e_entry += vdso_adjust; + phdr = (Elf_Phdr *)((caddr_t)ehdr + ehdr->e_phoff); + + /* phdrs */ + for (i = 0; i < ehdr->e_phnum; i++) { + phdr[i].p_vaddr += vdso_adjust; + if (phdr[i].p_type != PT_DYNAMIC) + continue; + dyn = (Elf_Dyn *)((caddr_t)ehdr + phdr[i].p_offset); + for(; dyn->d_tag != DT_NULL; dyn++) { + switch (dyn->d_tag) { + case DT_PLTGOT: + case DT_HASH: + case DT_STRTAB: + case DT_SYMTAB: + case DT_RELA: + case DT_INIT: + case DT_FINI: + case DT_REL: + case DT_DEBUG: + case DT_JMPREL: + case DT_VERSYM: + case DT_VERDEF: + case DT_VERNEED: + case DT_ADDRRNGLO ... DT_ADDRRNGHI: + dyn->d_un.d_ptr += vdso_adjust; + break; + case DT_ENCODING ... DT_LOOS-1: + case DT_LOOS ... DT_HIOS: + if (dyn->d_tag >= DT_ENCODING && + (dyn->d_tag & 1) == 0) + dyn->d_un.d_ptr += vdso_adjust; + break; + default: + break; + } + } + } + + /* sections */ + shdr = (Elf_Shdr *)((caddr_t)ehdr + ehdr->e_shoff); + for(i = 0; i < ehdr->e_shnum; i++) { + if (!(shdr[i].sh_flags & SHF_ALLOC)) + continue; + shdr[i].sh_addr += vdso_adjust; + if (shdr[i].sh_type != SHT_SYMTAB && + shdr[i].sh_type != SHT_DYNSYM) + continue; + + sym = (Elf_Sym *)((caddr_t)ehdr + shdr[i].sh_offset); + symcnt = shdr[i].sh_size / sizeof(*sym); + + for(i = 0; i < symcnt; i++, sym++) { + if (sym->st_shndx == SHN_UNDEF || + sym->st_shndx == SHN_ABS) + continue; + sym->st_value += vdso_adjust; + } + } + } + + SLIST_FOREACH(lsym, &__elfN(linux_vdso_syms), sym) + __elfN(linux_vdso_lookup)(ehdr, lsym); +} + +static void +__elfN(linux_vdso_lookup)(Elf_Ehdr *ehdr, struct linux_vdso_sym *vsym) +{ + vm_offset_t strtab, symname; + uint32_t symcnt; + Elf_Shdr *shdr; + int i; + + shdr = (Elf_Shdr *) ((caddr_t)ehdr + ehdr->e_shoff); + + strtab = (vm_offset_t)((caddr_t)ehdr + + shdr[__elfN(symstrindex)].sh_offset); + Elf_Sym *sym = (Elf_Sym *)((caddr_t)ehdr + + shdr[__elfN(symtabindex)].sh_offset); + symcnt = shdr[__elfN(symtabindex)].sh_size / sizeof(*sym); + + for (i = 0; i < symcnt; ++i, ++sym) { + symname = strtab + sym->st_name; + if (strncmp(vsym->symname, (char *)symname, vsym->size) == 0) { + *vsym->ptr = (uintptr_t)sym->st_value; + break; + } + } +} |