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      1 # Copyright 2017-2025 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 file is part of the gdb testsuite.
     17 
     18 # Test that GDB tolerates being started with libSegFault.so preloaded
     19 # with LD_PRELOAD, and that GDB warns about a custom SIGSEGV custom
     20 # handler.  See PR gdb/18653
     21 # <https://sourceware.org/bugzilla/show_bug.cgi?id=18653#c7>.
     22 
     23 # We cannot expect remote hosts to see environment variables set on
     24 # the local machine.
     25 require {!is_remote host}
     26 
     27 # Spawn GDB with LIB preloaded with LD_PRELOAD.  CMDLINE_OPTS are
     28 # command line options passed to GDB.
     29 
     30 proc gdb_spawn_with_ld_preload {lib cmdline_opts} {
     31     global env
     32 
     33     save_vars { env(LD_PRELOAD) env(ASAN_OPTIONS)} {
     34 	if { ![info exists env(LD_PRELOAD) ]
     35 	     || $env(LD_PRELOAD) == "" } {
     36 	    set env(LD_PRELOAD) "$lib"
     37 	} else {
     38 	    append env(LD_PRELOAD) ":$lib"
     39 	}
     40 
     41 	# Prevent address sanitizer error:
     42 	# ASan runtime does not come first in initial library list; you should
     43 	# either link runtime to your application or manually preload it with
     44 	# LD_PRELOAD.
     45 	append_environment_default ASAN_OPTIONS verify_asan_link_order 0
     46 
     47 	gdb_spawn_with_cmdline_opts $cmdline_opts
     48     }
     49 }
     50 
     51 proc test_libsegfault {} {
     52     global gdb_prompt
     53 
     54     set libsegfault "libSegFault.so"
     55 
     56     # When started normally, if libSegFault.so is preloaded, GDB
     57     # should warn about not being able to propagate the signal
     58     # disposition of SIGSEGV.
     59     gdb_exit
     60     gdb_spawn_with_ld_preload $libsegfault ""
     61 
     62     set test "gdb emits custom handler warning"
     63     gdb_test_multiple "" $test {
     64 	-re "cannot be preloaded.*\r\n$gdb_prompt $" {
     65 	    # Glibc 2.22 outputs:
     66 	    # ERROR: ld.so: object 'libSegFault.so' from LD_PRELOAD cannot be preloaded (cannot open shared object file): ignored.
     67 	    untested "cannot preload libSegFault.so"
     68 	    return
     69 	}
     70 	-re "Found custom handler.*won't be propagated.*\r\n$gdb_prompt $" {
     71 	    pass $test
     72 	}
     73     }
     74 
     75     # "-q" should disable the warning, though.
     76     gdb_exit
     77     gdb_spawn_with_ld_preload $libsegfault "-q"
     78 
     79     set test "quiet suppresses custom handler warning"
     80     gdb_test_multiple "" $test {
     81 	-re "^$gdb_prompt $" {
     82 	    pass $test
     83 	}
     84     }
     85 }
     86 
     87 save_vars { ::INTERNAL_GDBFLAGS } {
     88     set ::INTERNAL_GDBFLAGS [string map {"-q" ""} $::INTERNAL_GDBFLAGS]
     89     test_libsegfault
     90 }
     91