1ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown 2ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown/*--------------------------------------------------------------------*/ 3ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown/*--- User-mode execve(), and other stuff shared between stage1 ---*/ 4ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown/*--- and stage2. m_ume.c ---*/ 5ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown/*--------------------------------------------------------------------*/ 6ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown 7ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown/* 8ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown This file is part of Valgrind, a dynamic binary instrumentation 9ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown framework. 10ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown 11663860b1408516d02ebfcb3a9999a134e6cfb223Ben Cheng Copyright (C) 2000-2012 Julian Seward 12ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown jseward@acm.org 13ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown 14ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown This program is free software; you can redistribute it and/or 15ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown modify it under the terms of the GNU General Public License as 16ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown published by the Free Software Foundation; either version 2 of the 17ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown License, or (at your option) any later version. 18ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown 19ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown This program is distributed in the hope that it will be useful, but 20ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown WITHOUT ANY WARRANTY; without even the implied warranty of 21ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 22ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown General Public License for more details. 23ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown 24ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown You should have received a copy of the GNU General Public License 25ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown along with this program; if not, write to the Free Software 26ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 27ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown 02111-1307, USA. 28ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown 29ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown The GNU General Public License is contained in the file COPYING. 30ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown*/ 31ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown 32ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown 33ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown#include "pub_core_basics.h" 34ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown#include "pub_core_vki.h" 35ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown 36ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown#include "pub_core_libcbase.h" 37ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown#include "pub_core_libcassert.h" // VG_(exit), vg_assert 38ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown#include "pub_core_libcfile.h" // VG_(close) et al 39ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown#include "pub_core_libcprint.h" // VG_(message) 40ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown#include "pub_core_mallocfree.h" // VG_(strdup) 41ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown#include "pub_core_syscall.h" // VG_(mk_SysRes_Error) 42ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown#include "pub_core_options.h" // VG_(clo_xml) 43ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown#include "pub_core_ume.h" // self 44ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown 45ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown#include "priv_ume.h" 46ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown 47ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown 48ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Browntypedef struct { 49ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown Bool (*match_fn)(Char *hdr, Int len); 50ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown Int (*load_fn)(Int fd, const HChar *name, ExeInfo *info); 51ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown} ExeHandler; 52ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown 53ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brownstatic ExeHandler exe_handlers[] = { 54b32f58018498ea2225959b0ba11c18f0c433deefEvgeniy Stepanov# if defined(VGO_linux) 55ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown { VG_(match_ELF), VG_(load_ELF) }, 56b32f58018498ea2225959b0ba11c18f0c433deefEvgeniy Stepanov# elif defined(VGO_darwin) 57ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown { VG_(match_macho), VG_(load_macho) }, 58b32f58018498ea2225959b0ba11c18f0c433deefEvgeniy Stepanov# else 59b32f58018498ea2225959b0ba11c18f0c433deefEvgeniy Stepanov# error "unknown OS" 60b32f58018498ea2225959b0ba11c18f0c433deefEvgeniy Stepanov# endif 61ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown { VG_(match_script), VG_(load_script) }, 62ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown}; 63ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown#define EXE_HANDLER_COUNT (sizeof(exe_handlers)/sizeof(exe_handlers[0])) 64ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown 65ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown 66ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown// Check the file looks executable. 67ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff BrownSysRes 68ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff BrownVG_(pre_exec_check)(const HChar* exe_name, Int* out_fd, Bool allow_setuid) 69ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown{ 70ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown Int fd, ret, i; 71ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown SysRes res; 72ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown Char buf[4096]; 73ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown SizeT bufsz = 4096, fsz; 74ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown Bool is_setuid = False; 75ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown 76ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown // Check it's readable 77ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown res = VG_(open)(exe_name, VKI_O_RDONLY, 0); 78ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown if (sr_isError(res)) { 79ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown return res; 80ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown } 81ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown fd = sr_Res(res); 82ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown 83ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown // Check we have execute permissions 84ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown ret = VG_(check_executable)(&is_setuid, (HChar*)exe_name, allow_setuid); 85ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown if (0 != ret) { 86ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown VG_(close)(fd); 87ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown if (is_setuid && !VG_(clo_xml)) { 88ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown VG_(message)(Vg_UserMsg, "\n"); 89ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown VG_(message)(Vg_UserMsg, 90ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown "Warning: Can't execute setuid/setgid executable: %s\n", 91ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown exe_name); 92ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown VG_(message)(Vg_UserMsg, "Possible workaround: remove " 93ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown "--trace-children=yes, if in effect\n"); 94ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown VG_(message)(Vg_UserMsg, "\n"); 95ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown } 96ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown return VG_(mk_SysRes_Error)(ret); 97ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown } 98ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown 99ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown fsz = (SizeT)VG_(fsize)(fd); 100ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown if (fsz < bufsz) 101ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown bufsz = fsz; 102ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown 103ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown res = VG_(pread)(fd, buf, bufsz, 0); 104ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown if (sr_isError(res) || sr_Res(res) != bufsz) { 105ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown VG_(close)(fd); 106ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown return VG_(mk_SysRes_Error)(VKI_EACCES); 107ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown } 108ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown bufsz = sr_Res(res); 109ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown 110ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown // Look for a matching executable format 111ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown for (i = 0; i < EXE_HANDLER_COUNT; i++) { 112ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown if ((*exe_handlers[i].match_fn)(buf, bufsz)) { 113ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown res = VG_(mk_SysRes_Success)(i); 114ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown break; 115ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown } 116ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown } 117ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown if (i == EXE_HANDLER_COUNT) { 118ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown // Rejected by all executable format handlers. 119ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown res = VG_(mk_SysRes_Error)(VKI_ENOEXEC); 120ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown } 121ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown 122ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown // Write the 'out_fd' param if necessary, or close the file. 123ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown if (!sr_isError(res) && out_fd) { 124ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown *out_fd = fd; 125ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown } else { 126ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown VG_(close)(fd); 127ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown } 128ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown 129ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown return res; 130ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown} 131ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown 132ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown// returns: 0 = success, non-0 is failure 133ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown// 134ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown// We can execute only binaries (ELF, etc) or scripts that begin with "#!". 135ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown// (Not, for example, scripts that don't begin with "#!"; see the 136ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown// VG_(do_exec)() invocation from m_main.c for how that's handled.) 137ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff BrownInt VG_(do_exec_inner)(const HChar* exe, ExeInfo* info) 138ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown{ 139ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown SysRes res; 140ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown Int fd; 141ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown Int ret; 142ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown 143ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown res = VG_(pre_exec_check)(exe, &fd, False/*allow_setuid*/); 144ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown if (sr_isError(res)) 145ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown return sr_Err(res); 146ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown 147ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown vg_assert2(sr_Res(res) >= 0 && sr_Res(res) < EXE_HANDLER_COUNT, 148ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown "invalid VG_(pre_exec_check) result"); 149ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown 150ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown ret = (*exe_handlers[sr_Res(res)].load_fn)(fd, exe, info); 151ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown 152ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown VG_(close)(fd); 153ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown 154ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown return ret; 155ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown} 156ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown 157ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown 158ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brownstatic Bool is_hash_bang_file(Char* f) 159ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown{ 160ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown SysRes res = VG_(open)(f, VKI_O_RDONLY, 0); 161ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown if (!sr_isError(res)) { 162ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown Char buf[3] = {0,0,0}; 163ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown Int fd = sr_Res(res); 164ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown Int n = VG_(read)(fd, buf, 2); 165ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown if (n == 2 && VG_STREQ("#!", buf)) 166ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown return True; 167ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown } 168ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown return False; 169ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown} 170ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown 171ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown// Look at the first 80 chars, and if any are greater than 127, it's binary. 172ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown// This is crude, but should be good enough. Note that it fails on a 173ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown// zero-length file, as we want. 174ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brownstatic Bool is_binary_file(Char* f) 175ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown{ 176ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown SysRes res = VG_(open)(f, VKI_O_RDONLY, 0); 177ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown if (!sr_isError(res)) { 178ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown UChar buf[80]; 179ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown Int fd = sr_Res(res); 180ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown Int n = VG_(read)(fd, buf, 80); 181ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown Int i; 182ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown for (i = 0; i < n; i++) { 183ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown if (buf[i] > 127) 184ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown return True; // binary char found 185ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown } 186ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown return False; 187ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown } else { 188ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown // Something went wrong. This will only happen if we earlier 189ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown // succeeded in opening the file but fail here (eg. the file was 190ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown // deleted between then and now). 191ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown VG_(fmsg)("%s: unknown error\n", f); 192ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown VG_(exit)(126); // 126 == NOEXEC 193ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown } 194ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown} 195ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown 196ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown// If the do_exec fails we try to emulate what the shell does (I used 197ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown// bash as a guide). It's worth noting that the shell can execute some 198ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown// things that VG_(do_exec)() (which subsitutes for the kernel's exec()) 199ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown// will refuse to (eg. scripts lacking a "#!" prefix). 200ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brownstatic Int do_exec_shell_followup(Int ret, HChar* exe_name, ExeInfo* info) 201ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown{ 202663860b1408516d02ebfcb3a9999a134e6cfb223Ben Cheng# if defined(VGPV_arm_linux_android) || defined(VGPV_x86_linux_android) 203b32f58018498ea2225959b0ba11c18f0c433deefEvgeniy Stepanov Char* default_interp_name = "/system/bin/sh"; 204b32f58018498ea2225959b0ba11c18f0c433deefEvgeniy Stepanov# else 205ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown Char* default_interp_name = "/bin/sh"; 206b32f58018498ea2225959b0ba11c18f0c433deefEvgeniy Stepanov# endif 207b32f58018498ea2225959b0ba11c18f0c433deefEvgeniy Stepanov 208ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown SysRes res; 209ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown struct vg_stat st; 210ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown 211ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown if (VKI_ENOEXEC == ret) { 212ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown // It was an executable file, but in an unacceptable format. Probably 213ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown // is a shell script lacking the "#!" prefix; try to execute it so. 214ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown 215ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown // Is it a binary file? 216ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown if (is_binary_file(exe_name)) { 217ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown VG_(fmsg)("%s: cannot execute binary file\n", exe_name); 218ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown VG_(exit)(126); // 126 == NOEXEC 219ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown } 220ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown 221ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown // Looks like a script. Run it with /bin/sh. This includes 222ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown // zero-length files. 223ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown 224ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown info->interp_name = VG_(strdup)("ume.desf.1", default_interp_name); 225ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown info->interp_args = NULL; 226ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown if (info->argv && info->argv[0] != NULL) 227ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown info->argv[0] = (char *)exe_name; 228ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown 229ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown ret = VG_(do_exec_inner)(info->interp_name, info); 230ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown 231ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown if (0 != ret) { 232ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown // Something went wrong with executing the default interpreter 233ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown VG_(fmsg)("%s: bad interpreter (%s): %s\n", 234ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown exe_name, info->interp_name, VG_(strerror)(ret)); 235ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown VG_(exit)(126); // 126 == NOEXEC 236ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown } 237ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown 238ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown } else if (0 != ret) { 239ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown // Something else went wrong. Try to make the error more specific, 240ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown // and then print a message and abort. 241ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown 242ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown // Was it a directory? 243ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown res = VG_(stat)(exe_name, &st); 244ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown if (!sr_isError(res) && VKI_S_ISDIR(st.mode)) { 245ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown VG_(fmsg)("%s: is a directory\n", exe_name); 246ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown 247ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown // Was it not executable? 248ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown } else if (0 != VG_(check_executable)(NULL, exe_name, 249ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown False/*allow_setuid*/)) { 250ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown VG_(fmsg)("%s: %s\n", exe_name, VG_(strerror)(ret)); 251ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown 252ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown // Did it start with "#!"? If so, it must have been a bad interpreter. 253ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown } else if (is_hash_bang_file(exe_name)) { 254ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown VG_(fmsg)("%s: bad interpreter: %s\n", exe_name, VG_(strerror)(ret)); 255ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown 256ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown // Otherwise it was something else. 257ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown } else { 258ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown VG_(fmsg)("%s: %s\n", exe_name, VG_(strerror)(ret)); 259ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown } 260ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown // 126 means NOEXEC; I think this is Posix, and that in some cases we 261ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown // should be returning 127, meaning NOTFOUND. Oh well. 262ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown VG_(exit)(126); 263ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown } 264ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown return ret; 265ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown} 266ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown 267ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown 268ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown// This emulates the kernel's exec(). If it fails, it then emulates the 269ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown// shell's handling of the situation. 270ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown// See ume.h for an indication of which entries of 'info' are inputs, which 271ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown// are outputs, and which are both. 272ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown/* returns: 0 = success, non-0 is failure */ 273ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff BrownInt VG_(do_exec)(const HChar* exe_name, ExeInfo* info) 274ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown{ 275ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown Int ret; 276ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown 277ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown info->interp_name = NULL; 278ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown info->interp_args = NULL; 279ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown 280ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown ret = VG_(do_exec_inner)(exe_name, info); 281ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown 282ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown if (0 != ret) { 283ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown Char* exe_name_casted = (Char*)exe_name; 284ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown ret = do_exec_shell_followup(ret, exe_name_casted, info); 285ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown } 286ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown return ret; 287ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown} 288ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown 289ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown/*--------------------------------------------------------------------*/ 290ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown/*--- end ---*/ 291ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown/*--------------------------------------------------------------------*/ 292