gdb/testsuite/gdb.base/attach-pie-misread.exp

   1 # Copyright 2010-2020 Free Software Foundation, Inc.
   2
   3 # This program is free software; you can redistribute it and/or modify
   4 # it under the terms of the GNU General Public License as published by
   5 # the Free Software Foundation; either version 3 of the License, or
   6 # (at your option) any later version.
   7 #
   8 # This program is distributed in the hope that it will be useful,
   9 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  10 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11 # GNU General Public License for more details.
  12 #
  13 # You should have received a copy of the GNU General Public License
  14 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
  15
  16 # This test only works on GNU/Linux.
  17 if { ![isnative] || [is_remote host] || [use_gdb_stub]
  18      || ![istarget *-linux*] || [skip_shlib_tests]} {
  19     continue
  20 }
  21
  22 load_lib prelink-support.exp
  23
  24 standard_testfile .c
  25 set genfile [standard_output_file ${testfile}-gen.h]
  26 set executable $testfile
  27
  28 if {[build_executable_own_libs ${testfile}.exp $executable $srcfile [list additional_flags=-fPIE ldflags=-pie]] == ""} {
  29     return -1
  30 }
  31
  32 # Program Headers:
  33 #   Type           Offset   VirtAddr           PhysAddr           FileSiz  MemSiz   Flg Align
  34 #   LOAD           0x000000 0x0000000000400000 0x0000000000400000 0x134f5ec 0x134f5ec R E 0x200000
  35 #   LOAD           0x134f5f0 0x000000000194f5f0 0x000000000194f5f0 0x1dbc60 0x214088 RW  0x200000
  36 #   DYNAMIC        0x134f618 0x000000000194f618 0x000000000194f618 0x000200 0x000200 RW  0x8
  37 #
  38 proc read_phdr {binfile test} {
  39     set readelf_program [gdb_find_readelf]
  40     set command "exec $readelf_program -Wl $binfile"
  41     verbose -log "command is $command"
  42     set result [catch $command output]
  43     verbose -log "result is $result"
  44     verbose -log "output is $output"
  45     if {$result != 0} {
  46         fail $test
  47         return
  48     }
  49     if ![regexp {\nProgram Headers:\n *Type [^\n]* Align\n(.*?)\n\n} $output trash phdr] {
  50         fail "$test (no Program Headers)"
  51         return
  52     }
  53     if ![regexp -line {^ *DYNAMIC +0x[0-9a-f]+ +(0x[0-9a-f]+) } $phdr trash dynamic_vaddr] {
  54         fail "$test (no DYNAMIC found)"
  55         return
  56     }
  57     verbose -log "dynamic_vaddr is $dynamic_vaddr"
  58     set align_max -1
  59     foreach {trash align} [regexp -line -all -inline {^ *LOAD .* (0x[0-9]+)$} $phdr] {
  60         if {$align_max < $align} {
  61             set align_max $align
  62         }
  63     }
  64     verbose -log "align_max is $align_max"
  65     if {$align_max == -1} {
  66         fail "$test (no LOAD found)"
  67         return
  68     }
  69     pass $test
  70     return [list $dynamic_vaddr $align_max]
  71 }
  72
  73 set phdr [read_phdr $binfile "readelf initial scan"]
  74 set dynamic_vaddr [lindex $phdr 0]
  75 set align_max [lindex $phdr 1]
  76
  77 set stub_size [format 0x%x [expr "2 * $align_max - ($dynamic_vaddr & ($align_max - 1))"]]
  78 verbose -log "stub_size is $stub_size"
  79
  80 # On x86_64 it is commonly about 4MB.
  81 if {$stub_size > 25000000} {
  82     xfail "stub size $stub_size is too large"
  83     return
  84 }
  85
  86 set test "generate stub"
  87 set command "exec $binfile $stub_size >$genfile"
  88 verbose -log "command is $command"
  89 set result [catch $command output]
  90 verbose -log "result is $result"
  91 verbose -log "output is $output"
  92 if {$result == 0} {
  93     pass $test
  94 } else {
  95     fail $test
  96 }
  97
  98 set prelink_args [build_executable_own_libs ${test}.exp $executable $srcfile [list "additional_flags=-fPIE -DGEN=\"$genfile\"" "ldflags=-pie"]]
  99 if {$prelink_args == ""} {
 100     return -1
 101 }
 102
 103 # x86_64 file has 25MB, no need to keep it.
 104 file delete -- $genfile
 105
 106 set phdr [read_phdr $binfile "readelf rebuilt with stub_size"]
 107 set dynamic_vaddr_prelinkno [lindex $phdr 0]
 108
 109 if ![prelink_yes $prelink_args] {
 110     return -1
 111 }
 112
 113 set phdr [read_phdr $binfile "readelf with prelink -R"]
 114 set dynamic_vaddr_prelinkyes [lindex $phdr 0]
 115
 116 set first_offset [format 0x%x [expr $dynamic_vaddr_prelinkyes - $dynamic_vaddr_prelinkno]]
 117 verbose -log "first_offset is $first_offset"
 118
 119 set test "first offset is non-zero"
 120 if {$first_offset == 0} {
 121     fail "$test (-fPIE -pie in effect?)"
 122 } else {
 123     pass $test
 124 }
 125
 126 set test "start inferior"
 127 gdb_exit
 128
 129 set test_spawn_id [remote_spawn host $binfile]
 130 if { $test_spawn_id < 0 || $test_spawn_id == "" } {
 131     perror "Spawning $binfile failed."
 132     fail $test
 133     return
 134 }
 135 set testpid [spawn_id_get_pid $test_spawn_id]
 136 gdb_expect {
 137     -re "sleeping\r\n" {
 138         pass $test
 139     }
 140     eof {
 141         fail "$test (eof)"
 142         wait -i $test_spawn_id
 143         return
 144     }
 145     timeout {
 146         fail "$test (timeout)"
 147         kill_wait_spawned_process $test_spawn_id
 148         return
 149     }
 150 }
 151
 152 # Due to alignments it was reproducible with 1 on x86_64 but 2 on i686.
 153 foreach align_mult {1 2} { with_test_prefix "shift-by-$align_mult" {
 154
 155     # FIXME: We believe there is enough room under FIRST_OFFSET.
 156     set shifted_offset [format 0x%x [expr "$first_offset - $align_mult * $align_max"]]
 157     verbose -log "shifted_offset is $shifted_offset"
 158
 159     # For normal prelink (prelink_yes call), we need to supply $prelink_args.
 160     # For the prelink `-r' option below, $prelink_args is not required.
 161     # Moreover, if it was used, the problem would not longer be reproducible
 162     # as the libraries would also get relocated.
 163     set command "exec /usr/sbin/prelink -q -N --no-exec-shield -r $shifted_offset $binfile"
 164     verbose -log "command is $command"
 165     set result [catch $command output]
 166     verbose -log "result is $result"
 167     verbose -log "output is $output"
 168
 169     set test "prelink -r"
 170     if {$result == 0 && $output == ""} {
 171         pass $test
 172     } else {
 173         fail $test
 174     }
 175
 176     clean_restart $executable
 177
 178     set test "attach"
 179     gdb_test_multiple "attach $testpid" $test {
 180         -re "Attaching to program: .*, process $testpid\r\n" {
 181             # Missing "$gdb_prompt $" is intentional.
 182             pass $test
 183         }
 184     }
 185
 186     set test "error on Cannot access memory at address"
 187     gdb_test_multiple "" $test {
 188         -re "\r\nCannot access memory at address .*$gdb_prompt $" {
 189             fail $test
 190         }
 191         -re "$gdb_prompt $" {
 192             pass $test
 193         }
 194     }
 195
 196     gdb_test "detach" "Detaching from program: .*"
 197 }}
 198
 199 kill_wait_spawned_process $test_spawn_id