1 /*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 2019 Justin Hibbits
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer
11 * in this position and unchanged.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. The name of the author may not be used to endorse or promote products
16 * derived from this software without specific prior written permission
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
19 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
20 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
21 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
22 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
23 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
27 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28 */
29
30 static int
__elfN(powerpc_copyout_auxargs)31 __elfN(powerpc_copyout_auxargs)(struct image_params *imgp, uintptr_t base)
32 {
33 Elf_Auxargs *args;
34 Elf_Auxinfo *argarray, *pos;
35 struct vmspace *vmspace;
36 int error;
37
38 /*
39 * XXX If we can't find image's OSREL, assume it uses the new auxv
40 * format.
41 *
42 * This is specially important for rtld, that is not tagged. Using
43 * direct exec mode with new (ELFv2) binaries that expect the new auxv
44 * format would result in crashes otherwise.
45 *
46 * Unfortunately, this may break direct exec'ing old binaries,
47 * but it seems better to correctly support new binaries by default,
48 * considering the transition to ELFv2 happened quite some time
49 * ago. If needed, a sysctl may be added to allow old auxv format to
50 * be used when OSREL is not found.
51 */
52 if (imgp->proc->p_osrel >= P_OSREL_POWERPC_NEW_AUX_ARGS ||
53 imgp->proc->p_osrel == 0)
54 return (__elfN(freebsd_copyout_auxargs)(imgp, base));
55
56 args = (Elf_Auxargs *)imgp->auxargs;
57 argarray = pos = malloc(AT_OLD_COUNT * sizeof(*pos), M_TEMP,
58 M_WAITOK | M_ZERO);
59
60 vmspace = imgp->proc->p_vmspace;
61
62 if (args->execfd != -1)
63 AUXARGS_ENTRY(pos, AT_OLD_EXECFD, args->execfd);
64 AUXARGS_ENTRY(pos, AT_OLD_PHDR, args->phdr);
65 AUXARGS_ENTRY(pos, AT_OLD_PHENT, args->phent);
66 AUXARGS_ENTRY(pos, AT_OLD_PHNUM, args->phnum);
67 AUXARGS_ENTRY(pos, AT_OLD_PAGESZ, args->pagesz);
68 AUXARGS_ENTRY(pos, AT_OLD_FLAGS, args->flags);
69 AUXARGS_ENTRY(pos, AT_OLD_ENTRY, args->entry);
70 AUXARGS_ENTRY(pos, AT_OLD_BASE, args->base);
71 AUXARGS_ENTRY(pos, AT_OLD_EHDRFLAGS, args->hdr_eflags);
72 if (imgp->execpathp != 0)
73 AUXARGS_ENTRY_PTR(pos, AT_OLD_EXECPATH, imgp->execpathp);
74 AUXARGS_ENTRY(pos, AT_OLD_OSRELDATE,
75 imgp->proc->p_ucred->cr_prison->pr_osreldate);
76 if (imgp->canary != 0) {
77 AUXARGS_ENTRY_PTR(pos, AT_OLD_CANARY, imgp->canary);
78 AUXARGS_ENTRY(pos, AT_OLD_CANARYLEN, imgp->canarylen);
79 }
80 AUXARGS_ENTRY(pos, AT_OLD_NCPUS, mp_ncpus);
81 if (imgp->pagesizes != 0) {
82 AUXARGS_ENTRY_PTR(pos, AT_OLD_PAGESIZES, imgp->pagesizes);
83 AUXARGS_ENTRY(pos, AT_OLD_PAGESIZESLEN, imgp->pagesizeslen);
84 }
85 if ((imgp->sysent->sv_flags & SV_TIMEKEEP) != 0) {
86 AUXARGS_ENTRY(pos, AT_OLD_TIMEKEEP,
87 vmspace->vm_shp_base + imgp->sysent->sv_timekeep_offset);
88 }
89 AUXARGS_ENTRY(pos, AT_OLD_STACKPROT, imgp->sysent->sv_shared_page_obj
90 != NULL && imgp->stack_prot != 0 ? imgp->stack_prot :
91 imgp->sysent->sv_stackprot);
92 if (imgp->sysent->sv_hwcap != NULL)
93 AUXARGS_ENTRY(pos, AT_OLD_HWCAP, *imgp->sysent->sv_hwcap);
94 if (imgp->sysent->sv_hwcap2 != NULL)
95 AUXARGS_ENTRY(pos, AT_OLD_HWCAP2, *imgp->sysent->sv_hwcap2);
96 AUXARGS_ENTRY(pos, AT_OLD_NULL, 0);
97
98 free(imgp->auxargs, M_TEMP);
99 imgp->auxargs = NULL;
100 KASSERT(pos - argarray <= AT_OLD_COUNT, ("Too many auxargs"));
101
102 error = copyout(argarray, (void *)base, sizeof(*argarray) * AT_OLD_COUNT);
103 free(argarray, M_TEMP);
104 return (error);
105 }
106