diff options
| author |   matthew <matthew@openbsd.org> | 2012-08-20 23:25:07 +0000 |
|---|---|---|
| committer | matthew <matthew@openbsd.org> | 2012-08-20 23:25:07 +0000 |
| commit | 5f7066906156ece39fb432bab1cea4415d608bfc (patch) | |
| tree | c17c7fb24eb672c57598476e74a77656ffd85203 /sys/kern/exec_elf.c | |
| parent | MAX_LINE_SIZE is supposed to define the max length of a SMTP line ... (diff) | |
| download | wireguard-openbsd-5f7066906156ece39fb432bab1cea4415d608bfc.tar.xz wireguard-openbsd-5f7066906156ece39fb432bab1cea4415d608bfc.zip | |
Add support for .openbsd.randomdata sections and PT_OPENBSD_RANDOMIZE
segments to the kernel, ld (2.15), and ld.so. Tested on alpha, amd64,
i386, macppc, and sparc64 (thanks naddy, mpi, and okan!).
Idea discussed for some time; committing now for further testing.
ok deraadt
Diffstat (limited to 'sys/kern/exec_elf.c')
| -rw-r--r-- | sys/kern/exec_elf.c | 27 |
1 files changed, 26 insertions, 1 deletions
diff --git a/sys/kern/exec_elf.c b/sys/kern/exec_elf.c index 4e9f314965f..7cfa7d11ea6 100644 --- a/sys/kern/exec_elf.c +++ b/sys/kern/exec_elf.c @@ -1,4 +1,4 @@ -/* $OpenBSD: exec_elf.c,v 1.86 2012/03/09 13:01:28 ariane Exp $ */ +/* $OpenBSD: exec_elf.c,v 1.87 2012/08/20 23:25:07 matthew Exp $ */ /* * Copyright (c) 1996 Per Fogelstrom @@ -130,6 +130,9 @@ extern char *syscallnames[]; */ #define ELF_MAX_VALID_PHDR 32 +/* Limit on total PT_OPENBSD_RANDOMIZE bytes. */ +#define ELF_RANDOMIZE_LIMIT 1024 + /* * This is the basic elf emul. elf_probe_funcs may change to other emuls. */ @@ -327,6 +330,7 @@ ELFNAME(load_file)(struct proc *p, char *path, struct exec_package *epp, Elf_Addr pos = *last; int file_align; int loop; + size_t randomizequota = ELF_RANDOMIZE_LIMIT; NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, path, p); if ((error = namei(&nd)) != 0) { @@ -469,6 +473,16 @@ ELFNAME(load_file)(struct proc *p, char *path, struct exec_package *epp, case PT_NOTE: break; + case PT_OPENBSD_RANDOMIZE: + if (ph[i].p_memsz > randomizequota) { + error = ENOMEM; + goto bad1; + } + randomizequota -= ph[i].p_memsz; + NEW_VMCMD(&epp->ep_vmcmds, vmcmd_randomize, + ph[i].p_memsz, ph[i].p_vaddr + pos, NULLVP, 0, 0); + break; + default: break; } @@ -506,6 +520,7 @@ ELFNAME2(exec,makecmds)(struct proc *p, struct exec_package *epp) char *interp = NULL; u_long pos = 0, phsize; u_int8_t os = OOS_NULL; + size_t randomizequota = ELF_RANDOMIZE_LIMIT; if (epp->ep_hdrvalid < sizeof(Elf_Ehdr)) return (ENOEXEC); @@ -692,6 +707,16 @@ native: phdr = pp->p_vaddr; break; + case PT_OPENBSD_RANDOMIZE: + if (ph[i].p_memsz > randomizequota) { + error = ENOMEM; + goto bad; + } + randomizequota -= ph[i].p_memsz; + NEW_VMCMD(&epp->ep_vmcmds, vmcmd_randomize, + ph[i].p_memsz, ph[i].p_vaddr + exe_base, NULLVP, 0, 0); + break; + default: /* * Not fatal, we don't need to understand everything |