Really fix run-stap this time, I promise!

5 files changed, 35 insertions, 55 deletions

diff --git a/configure b/configure
index 33655cc2..03763d5a 100755
--- a/configure
+++ b/configure
@@ -667,7 +667,6 @@ sqlite3_LIBS
 PIECXXFLAGS
 PIECFLAGS
 PIELDFLAGS
-PERL
 RANLIB
 ANSI2KNR
 U
@@ -5972,47 +5971,6 @@ fi
 
 
 
-# Extract the first word of "perl", so it can be a program name with args.
-set dummy perl; ac_word=$2
-{ $as_echo "$as_me:$LINENO: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if test "${ac_cv_path_PERL+set}" = set; then
-  $as_echo_n "(cached) " >&6
-else
-  case $PERL in
-  [\\/]* | ?:[\\/]*)
-  ac_cv_path_PERL="$PERL" # Let the user override the test with a path.
-  ;;
-  *)
-  as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
-for as_dir in $PATH
-do
-  IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
-  for ac_exec_ext in '' $ac_executable_extensions; do
-  if { test -f "$as_dir/$ac_word$ac_exec_ext" && $as_test_x "$as_dir/$ac_word$ac_exec_ext"; }; then
-    ac_cv_path_PERL="$as_dir/$ac_word$ac_exec_ext"
-    $as_echo "$as_me:$LINENO: found $as_dir/$ac_word$ac_exec_ext" >&5
-    break 2
-  fi
-done
-done
-IFS=$as_save_IFS
-
-  ;;
-esac
-fi
-PERL=$ac_cv_path_PERL
-if test -n "$PERL"; then
-  { $as_echo "$as_me:$LINENO: result: $PERL" >&5
-$as_echo "$PERL" >&6; }
-else
-  { $as_echo "$as_me:$LINENO: result: no" >&5
-$as_echo "no" >&6; }
-fi
-
-
-
 # Check whether --enable-perfmon was given.
 if test "${enable_perfmon+set}" = set; then
   enableval=$enable_perfmon;
diff --git a/configure.ac b/configure.ac
index 9b66a724..ee8ae61f 100644
--- a/configure.ac
+++ b/configure.ac
@@ -25,8 +25,6 @@ AC_PROG_MAKE_SET
 AC_SUBST(CFLAGS)
 AC_SUBST(CXXFLAGS)
 
-AC_PATH_PROG(PERL, perl)
-
 dnl Handle the perfmon option.
 AC_ARG_ENABLE([perfmon],
   AS_HELP_STRING([--enable-perfmon@<:@=DIRECTORY@:>@],
diff --git a/run-stap.in b/run-stap.in
index 1bfb6a77..8b150ece 100644
--- a/run-stap.in
+++ b/run-stap.in
@@ -19,7 +19,7 @@ esac
 # Set all the variables to find the source and build trees.
 SYSTEMTAP_TAPSET="${srcdir}/tapset"
 SYSTEMTAP_RUNTIME="${srcdir}/runtime"
-SYSTEMTAP_STAPRUN="sudo -P builddir='${builddir}' ${builddir}/run-staprun"
+SYSTEMTAP_STAPRUN="${builddir}/run-staprun"
 export SYSTEMTAP_TAPSET SYSTEMTAP_RUNTIME SYSTEMTAP_STAPRUN
 
 # If there were private elfutils libs built, use them.
diff --git a/run-staprun.in b/run-staprun.in
index 0b5f795b..e0615556 100644
--- a/run-staprun.in
+++ b/run-staprun.in
@@ -1,13 +1,24 @@
-#!@PERL@ -w
+#!/bin/sh
 
-# Reset real IDs to those we had before we were sudo-invoked.
-# This gives staprun the IDs it expects from a setuid exec.
-$< = $ENV{'SUDO_UID'};
-$( = $ENV{'SUDO_GID'};
+srcdir='@abs_top_srcdir@'
+builddir='@abs_top_builddir@'
 
-$ENV{'SYSTEMTAP_STAPRUN'} = "sudo '$ENV{'builddir'}/staprun'";
-$ENV{'SYSTEMTAP_STAPIO'} = "$ENV{'builddir'}/stapio";
+rundir="${0%/*}"
+[ "$rundir" == "$0" ] || builddir="$rundir"
 
-exec { "$ENV{'builddir'}/staprun" } ('staprun', @ARGV);
+# Absolutify the paths.
+case "$srcdir" in
+/*) ;;
+*) srcdir=`cd "$srcdir" && pwd` || exit ;;
+esac
+case "$builddir" in
+/*) ;;
+*) builddir=`cd "$builddir" && pwd` || exit ;;
+esac
 
-exit;
+exec sudo -P "SYSTEMTAP_STAPIO=${builddir}/stapio" \
+             "SYSTEMTAP_STAPRUN=${builddir}/run-staprun" \
+             "SYSTEMTAP_RUNTIME=${srcdir}/runtime" \
+             "SYSTEMTAP_REAL_UID=`id -ru`" \
+             "SYSTEMTAP_REAL_GID=`id -rg`" \
+             ${builddir}/staprun ${1+"$@"}
diff --git a/runtime/staprun/staprun_funcs.c b/runtime/staprun/staprun_funcs.c
index e94e5d13..49b37988 100644
--- a/runtime/staprun/staprun_funcs.c
+++ b/runtime/staprun/staprun_funcs.c
@@ -316,8 +316,21 @@ int check_permissions(void)
 	int path_check = 0;
 
 	/* If we're root, we can do anything. */
-	if (getuid() == 0)
+	if (getuid() == 0) {
+		/* ... like overriding the real UID */
+		const char *env_id = getenv("SYSTEMTAP_REAL_UID");
+		if (env_id && setreuid(atoi(env_id), -1))
+			err("WARNING: couldn't set staprun UID to '%s': %s",
+				env_id, strerror(errno));
+
+		/* ... or overriding the real GID */
+		env_id = getenv("SYSTEMTAP_REAL_GID");
+		if (env_id && setregid(atoi(env_id), -1))
+			err("WARNING: couldn't set staprun GID to '%s': %s",
+				env_id, strerror(errno));
+
 		return 1;
+	}
 
 	/* Lookup the gid for group "stapdev" */
 	errno = 0;