1 /*- 2 * Copyright (c) 2014, 2015 The FreeBSD Foundation. 3 * Copyright (c) 2014, 2017 Andrew Turner. 4 * Copyright (c) 2018 Olivier Houchard 5 * All rights reserved. 6 * 7 * This software was developed by Andrew Turner under 8 * sponsorship from the FreeBSD Foundation. 9 * 10 * Portions of this software were developed by Konstantin Belousov 11 * under sponsorship from the FreeBSD Foundation. 12 * 13 * Redistribution and use in source and binary forms, with or without 14 * modification, are permitted provided that the following conditions 15 * are met: 16 * 1. Redistributions of source code must retain the above copyright 17 * notice, this list of conditions and the following disclaimer. 18 * 2. Redistributions in binary form must reproduce the above copyright 19 * notice, this list of conditions and the following disclaimer in the 20 * documentation and/or other materials provided with the distribution. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 */ 34 35 #include <sys/cdefs.h> 36 __FBSDID("$FreeBSD$"); 37 38 #define __ELF_WORD_SIZE 32 39 40 #include <sys/param.h> 41 #include <sys/kernel.h> 42 #include <sys/systm.h> 43 #include <sys/exec.h> 44 #include <sys/imgact.h> 45 #include <sys/linker.h> 46 #include <sys/proc.h> 47 #include <sys/reg.h> 48 #include <sys/sysent.h> 49 #include <sys/imgact_elf.h> 50 #include <sys/syscall.h> 51 #include <sys/signalvar.h> 52 #include <sys/vnode.h> 53 54 #include <machine/elf.h> 55 #include <machine/pcb.h> 56 #ifdef VFP 57 #include <machine/vfp.h> 58 #endif 59 60 #include <compat/freebsd32/freebsd32_util.h> 61 62 #define FREEBSD32_MINUSER 0x00001000 63 #define FREEBSD32_MAXUSER ((1ul << 32) - PAGE_SIZE) 64 #define FREEBSD32_SHAREDPAGE (FREEBSD32_MAXUSER - PAGE_SIZE) 65 #define FREEBSD32_USRSTACK FREEBSD32_SHAREDPAGE 66 67 extern const char *freebsd32_syscallnames[]; 68 69 extern char aarch32_sigcode[]; 70 extern int sz_aarch32_sigcode; 71 72 static int freebsd32_fetch_syscall_args(struct thread *td); 73 static void freebsd32_setregs(struct thread *td, struct image_params *imgp, 74 u_long stack); 75 static void freebsd32_set_syscall_retval(struct thread *, int); 76 77 static bool elf32_arm_abi_supported(struct image_params *, int32_t *, 78 uint32_t *); 79 80 extern void freebsd32_sendsig(sig_t catcher, ksiginfo_t *ksi, sigset_t *mask); 81 82 u_long __read_frequently elf32_hwcap; 83 u_long __read_frequently elf32_hwcap2; 84 85 static struct sysentvec elf32_freebsd_sysvec = { 86 .sv_size = SYS_MAXSYSCALL, 87 .sv_table = freebsd32_sysent, 88 .sv_fixup = elf32_freebsd_fixup, 89 .sv_sendsig = freebsd32_sendsig, 90 .sv_sigcode = aarch32_sigcode, 91 .sv_szsigcode = &sz_aarch32_sigcode, 92 .sv_name = "FreeBSD ELF32", 93 .sv_coredump = elf32_coredump, 94 .sv_elf_core_osabi = ELFOSABI_FREEBSD, 95 .sv_elf_core_abi_vendor = FREEBSD_ABI_VENDOR, 96 .sv_elf_core_prepare_notes = elf32_prepare_notes, 97 .sv_minsigstksz = MINSIGSTKSZ, 98 .sv_minuser = FREEBSD32_MINUSER, 99 .sv_maxuser = FREEBSD32_MAXUSER, 100 .sv_usrstack = FREEBSD32_USRSTACK, 101 .sv_psstrings = FREEBSD32_PS_STRINGS, 102 .sv_psstringssz = sizeof(struct freebsd32_ps_strings), 103 .sv_stackprot = VM_PROT_READ | VM_PROT_WRITE, 104 .sv_copyout_auxargs = elf32_freebsd_copyout_auxargs, 105 .sv_copyout_strings = freebsd32_copyout_strings, 106 .sv_setregs = freebsd32_setregs, 107 .sv_fixlimit = NULL, // XXX 108 .sv_maxssiz = NULL, 109 .sv_flags = SV_ABI_FREEBSD | SV_ILP32 | SV_SHP | SV_TIMEKEEP | 110 SV_RNG_SEED_VER, 111 .sv_set_syscall_retval = freebsd32_set_syscall_retval, 112 .sv_fetch_syscall_args = freebsd32_fetch_syscall_args, 113 .sv_syscallnames = freebsd32_syscallnames, 114 .sv_shared_page_base = FREEBSD32_SHAREDPAGE, 115 .sv_shared_page_len = PAGE_SIZE, 116 .sv_schedtail = NULL, 117 .sv_thread_detach = NULL, 118 .sv_trap = NULL, 119 .sv_hwcap = &elf32_hwcap, 120 .sv_hwcap2 = &elf32_hwcap2, 121 .sv_onexec_old = exec_onexec_old, 122 .sv_onexit = exit_onexit, 123 .sv_regset_begin = SET_BEGIN(__elfN(regset)), 124 .sv_regset_end = SET_LIMIT(__elfN(regset)), 125 }; 126 INIT_SYSENTVEC(elf32_sysvec, &elf32_freebsd_sysvec); 127 128 static Elf32_Brandinfo freebsd32_brand_info = { 129 .brand = ELFOSABI_FREEBSD, 130 .machine = EM_ARM, 131 .compat_3_brand = "FreeBSD", 132 .interp_path = "/libexec/ld-elf.so.1", 133 .sysvec = &elf32_freebsd_sysvec, 134 .interp_newpath = "/libexec/ld-elf32.so.1", 135 .brand_note = &elf32_freebsd_brandnote, 136 .flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE, 137 .header_supported= elf32_arm_abi_supported, 138 }; 139 140 SYSINIT(elf32, SI_SUB_EXEC, SI_ORDER_FIRST, 141 (sysinit_cfunc_t)elf32_insert_brand_entry, &freebsd32_brand_info); 142 143 static bool 144 elf32_arm_abi_supported(struct image_params *imgp, int32_t *osrel __unused, 145 uint32_t *fctl0 __unused) 146 { 147 const Elf32_Ehdr *hdr; 148 149 /* Check if we support AArch32 */ 150 if (ID_AA64PFR0_EL0_VAL(READ_SPECIALREG(id_aa64pfr0_el1)) != 151 ID_AA64PFR0_EL0_64_32) 152 return (false); 153 154 #define EF_ARM_EABI_FREEBSD_MIN EF_ARM_EABI_VER4 155 hdr = (const Elf32_Ehdr *)imgp->image_header; 156 if (EF_ARM_EABI_VERSION(hdr->e_flags) < EF_ARM_EABI_FREEBSD_MIN) { 157 if (bootverbose) 158 uprintf("Attempting to execute non EABI binary " 159 "(rev %d) image %s", 160 EF_ARM_EABI_VERSION(hdr->e_flags), 161 imgp->args->fname); 162 return (false); 163 } 164 165 return (true); 166 } 167 168 static int 169 freebsd32_fetch_syscall_args(struct thread *td) 170 { 171 struct proc *p; 172 register_t *ap; 173 struct syscall_args *sa; 174 int error, i, nap, narg; 175 unsigned int args[4]; 176 177 nap = 4; 178 p = td->td_proc; 179 ap = td->td_frame->tf_x; 180 sa = &td->td_sa; 181 182 /* r7 is the syscall id */ 183 sa->code = td->td_frame->tf_x[7]; 184 sa->original_code = sa->code; 185 186 if (sa->code == SYS_syscall) { 187 sa->code = *ap++; 188 nap--; 189 } else if (sa->code == SYS___syscall) { 190 sa->code = ap[1]; 191 nap -= 2; 192 ap += 2; 193 } 194 195 if (sa->code >= p->p_sysent->sv_size) 196 sa->callp = &p->p_sysent->sv_table[0]; 197 else 198 sa->callp = &p->p_sysent->sv_table[sa->code]; 199 200 narg = sa->callp->sy_narg; 201 for (i = 0; i < nap; i++) 202 sa->args[i] = ap[i]; 203 if (narg > nap) { 204 if (narg - nap > nitems(args)) 205 panic("Too many system call arguiments"); 206 error = copyin((void *)td->td_frame->tf_x[13], args, 207 (narg - nap) * sizeof(int)); 208 if (error != 0) 209 return (error); 210 for (i = 0; i < (narg - nap); i++) 211 sa->args[i + nap] = args[i]; 212 } 213 214 td->td_retval[0] = 0; 215 td->td_retval[1] = 0; 216 217 return (0); 218 } 219 220 static void 221 freebsd32_set_syscall_retval(struct thread *td, int error) 222 { 223 struct trapframe *frame; 224 225 frame = td->td_frame; 226 switch (error) { 227 case 0: 228 frame->tf_x[0] = td->td_retval[0]; 229 frame->tf_x[1] = td->td_retval[1]; 230 frame->tf_spsr &= ~PSR_C; 231 break; 232 case ERESTART: 233 /* 234 * Reconstruct the pc to point at the swi. 235 */ 236 if ((frame->tf_spsr & PSR_T) != 0) 237 frame->tf_elr -= 2; //THUMB_INSN_SIZE; 238 else 239 frame->tf_elr -= 4; //INSN_SIZE; 240 break; 241 case EJUSTRETURN: 242 /* nothing to do */ 243 break; 244 default: 245 frame->tf_x[0] = error; 246 frame->tf_spsr |= PSR_C; 247 break; 248 } 249 } 250 251 static void 252 freebsd32_setregs(struct thread *td, struct image_params *imgp, 253 uintptr_t stack) 254 { 255 struct trapframe *tf = td->td_frame; 256 struct pcb *pcb = td->td_pcb; 257 258 memset(tf, 0, sizeof(struct trapframe)); 259 260 /* 261 * We need to set x0 for init as it doesn't call 262 * cpu_set_syscall_retval to copy the value. We also 263 * need to set td_retval for the cases where we do. 264 */ 265 tf->tf_x[0] = stack; 266 /* SP_usr is mapped to x13 */ 267 tf->tf_x[13] = stack; 268 /* LR_usr is mapped to x14 */ 269 tf->tf_x[14] = imgp->entry_addr; 270 tf->tf_elr = imgp->entry_addr; 271 tf->tf_spsr = PSR_M_32; 272 if ((uint32_t)imgp->entry_addr & 1) 273 tf->tf_spsr |= PSR_T; 274 275 #ifdef VFP 276 vfp_reset_state(td, pcb); 277 #endif 278 279 /* 280 * Clear debug register state. It is not applicable to the new process. 281 */ 282 bzero(&pcb->pcb_dbg_regs, sizeof(pcb->pcb_dbg_regs)); 283 } 284 285 void 286 elf32_dump_thread(struct thread *td, void *dst, size_t *off) 287 { 288 } 289