diff options
Diffstat (limited to 'sys/kern/exec_elf.c')
| -rw-r--r-- | sys/kern/exec_elf.c | 76 |
1 files changed, 53 insertions, 23 deletions
diff --git a/sys/kern/exec_elf.c b/sys/kern/exec_elf.c index 19f4e36933f..bfff39083f3 100644 --- a/sys/kern/exec_elf.c +++ b/sys/kern/exec_elf.c @@ -1,4 +1,4 @@ -/* $OpenBSD: exec_elf.c,v 1.65 2008/06/12 17:02:04 miod Exp $ */ +/* $OpenBSD: exec_elf.c,v 1.66 2008/07/18 16:58:06 kurt Exp $ */ /* * Copyright (c) 1996 Per Fogelstrom @@ -86,7 +86,7 @@ struct ELFNAME(probe_entry) { int ELFNAME(load_file)(struct proc *, char *, struct exec_package *, struct elf_args *, Elf_Addr *); -int ELFNAME(check_header)(Elf_Ehdr *, int); +int ELFNAME(check_header)(Elf_Ehdr *); int ELFNAME(read_from)(struct proc *, struct vnode *, u_long, caddr_t, int); void ELFNAME(load_psection)(struct exec_vmcmd_set *, struct vnode *, Elf_Phdr *, Elf_Addr *, Elf_Addr *, int *, int); @@ -157,7 +157,7 @@ ELFNAME(copyargs)(struct exec_package *pack, struct ps_strings *arginfo, * Check header for validity; return 0 for ok, ENOEXEC if error */ int -ELFNAME(check_header)(Elf_Ehdr *ehdr, int type) +ELFNAME(check_header)(Elf_Ehdr *ehdr) { /* * We need to check magic, class size, endianess, and version before @@ -175,10 +175,6 @@ ELFNAME(check_header)(Elf_Ehdr *ehdr, int type) ehdr->e_version != ELF_TARG_VER) return (ENOEXEC); - /* Check the type */ - if (ehdr->e_type != type) - return (ENOEXEC); - /* Don't allow an insane amount of sections. */ if (ehdr->e_phnum > ELF_MAX_VALID_PHDR) return (ENOEXEC); @@ -327,7 +323,7 @@ ELFNAME(load_file)(struct proc *p, char *path, struct exec_package *epp, (caddr_t)&eh, sizeof(eh))) != 0) goto bad1; - if (ELFNAME(check_header)(&eh, ET_DYN)) { + if (ELFNAME(check_header)(&eh) || eh.e_type != ET_DYN) { error = ENOEXEC; goto bad1; } @@ -474,8 +470,8 @@ int ELFNAME2(exec,makecmds)(struct proc *p, struct exec_package *epp) { Elf_Ehdr *eh = epp->ep_hdr; - Elf_Phdr *ph, *pp; - Elf_Addr phdr = 0; + Elf_Phdr *ph, *pp, *base_ph = NULL; + Elf_Addr phdr = 0, exe_base = 0; int error, i; char *interp = NULL; u_long pos = 0, phsize; @@ -484,7 +480,8 @@ ELFNAME2(exec,makecmds)(struct proc *p, struct exec_package *epp) if (epp->ep_hdrvalid < sizeof(Elf_Ehdr)) return (ENOEXEC); - if (ELFNAME(check_header)(eh, ET_EXEC)) + if (ELFNAME(check_header)(eh) || + (eh->e_type != ET_EXEC && eh->e_type != ET_DYN)) return (ENOEXEC); /* @@ -512,9 +509,8 @@ ELFNAME2(exec,makecmds)(struct proc *p, struct exec_package *epp) epp->ep_tsize = ELFDEFNNAME(NO_ADDR); epp->ep_dsize = ELFDEFNNAME(NO_ADDR); - for (i = 0; i < eh->e_phnum; i++) { - pp = &ph[i]; - if (pp->p_type == PT_INTERP) { + for (i = 0, pp = ph; i < eh->e_phnum; i++, pp++) { + if (pp->p_type == PT_INTERP && !interp) { if (pp->p_filesz >= MAXPATHLEN) goto bad; interp = pool_get(&namei_pool, PR_WAITOK); @@ -522,10 +518,20 @@ ELFNAME2(exec,makecmds)(struct proc *p, struct exec_package *epp) pp->p_offset, interp, pp->p_filesz)) != 0) { goto bad; } - break; + } else if (pp->p_type == PT_LOAD) { + if (base_ph == NULL) + base_ph = pp; } } + if (eh->e_type == ET_DYN) { + /* need an interpreter and load sections for PIE */ + if (interp == NULL || base_ph == NULL) + goto bad; + /* randomize exe_base for PIE */ + exe_base = uvm_map_pie(base_ph->p_align); + } + /* * OK, we want a slightly different twist of the * standard emulation package for "real" elf. @@ -560,17 +566,28 @@ ELFNAME2(exec,makecmds)(struct proc *p, struct exec_package *epp) #else native: #endif /* NATIVE_EXEC_ELF */ + /* * Load all the necessary sections */ - for (i = 0; i < eh->e_phnum; i++) { - Elf_Addr addr = ELFDEFNNAME(NO_ADDR), size = 0; + for (i = 0, pp = ph; i < eh->e_phnum; i++, pp++) { + Elf_Addr addr, size = 0; int prot = 0; + int flags = 0; - pp = &ph[i]; - - switch (ph[i].p_type) { + switch (pp->p_type) { case PT_LOAD: + if (exe_base != 0) { + if (pp == base_ph) { + flags = VMCMD_BASE; + addr = exe_base; + } else { + flags = VMCMD_RELATIVE; + addr = pp->p_vaddr - base_ph->p_vaddr; + } + } else + addr = ELFDEFNNAME(NO_ADDR); + /* * Calculates size of text and data segments * by starting at first and going to end of last. @@ -579,7 +596,18 @@ native: * for DATA_PLT, is fine for TEXT_PLT. */ ELFNAME(load_psection)(&epp->ep_vmcmds, epp->ep_vp, - &ph[i], &addr, &size, &prot, 0); + pp, &addr, &size, &prot, flags); + + /* + * Update exe_base in case allignment was off. + * For PIE, addr is relative to exe_base so + * adjust it (non PIE exe_base is 0 so no change). + */ + if (flags == VMCMD_BASE) + exe_base = addr; + else + addr += exe_base; + /* * Decide whether it's text or data by looking * at the protection of the section @@ -643,6 +671,8 @@ native: } } + phdr += exe_base; + /* * Strangely some linux programs may have all load sections marked * writeable, in this case, textsize is not -1, but rather 0; @@ -660,7 +690,7 @@ native: } epp->ep_interp = interp; - epp->ep_entry = eh->e_entry; + epp->ep_entry = eh->e_entry + exe_base; /* * Check if we found a dynamically linked binary and arrange to load @@ -674,7 +704,7 @@ native: ap->arg_phaddr = phdr; ap->arg_phentsize = eh->e_phentsize; ap->arg_phnum = eh->e_phnum; - ap->arg_entry = eh->e_entry; + ap->arg_entry = eh->e_entry + exe_base; ap->arg_os = os; epp->ep_emul_arg = ap; |