From: Tom Hughes <tom@compton.nu>
Date: Mon, 18 Jul 2005 14:02:11 +0000 (+0000)
Subject: Take a copy of the environment given to execve before trying to mangle
X-Git-Tag: svn/VALGRIND_3_0_0~156
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=a85d532b0def414788fa22f0777ab25c1c75c03f;p=thirdparty%2Fvalgrind.git

Take a copy of the environment given to execve before trying to mangle
it as it might be in read only memory. Fixes bug #101881.


git-svn-id: svn://svn.valgrind.org/valgrind/trunk@4162
---

diff --git a/coregrind/m_libcproc.c b/coregrind/m_libcproc.c
index d910bc7828..0851003e48 100644
--- a/coregrind/m_libcproc.c
+++ b/coregrind/m_libcproc.c
@@ -239,7 +239,7 @@ Int VG_(poll)( struct vki_pollfd *ufds, UInt nfds, Int timeout)
 }
 
 /* clone the environment */
-static Char **env_clone ( Char **oldenv )
+Char **VG_(env_clone) ( Char **oldenv )
 {
    Char **oldenvp;
    Char **newenvp;
@@ -284,7 +284,7 @@ Int VG_(system) ( Char* cmd )
       /* restore the DATA rlimit for the child */
       VG_(setrlimit)(VKI_RLIMIT_DATA, &VG_(client_rlimit_data));
 
-      envp = env_clone(VG_(client_envp));
+      envp = VG_(env_clone)(VG_(client_envp));
       VG_(env_remove_valgrind_env_stuff)( envp ); 
 
       argv[0] = "/bin/sh";
diff --git a/coregrind/m_syswrap/syswrap-generic.c b/coregrind/m_syswrap/syswrap-generic.c
index 43a8a5a3be..42beaed30e 100644
--- a/coregrind/m_syswrap/syswrap-generic.c
+++ b/coregrind/m_syswrap/syswrap-generic.c
@@ -2271,6 +2271,7 @@ void VG_(reap_threads)(ThreadId self)
 PRE(sys_execve)
 {
    Char*        path;          /* path to executable */
+   Char**       envp;
    ThreadState* tst;
 
    PRINT("sys_execve ( %p(%s), %p, %p )", ARG1, ARG1, ARG2, ARG3);
@@ -2317,14 +2318,13 @@ PRE(sys_execve)
    VG_(nuke_all_threads_except)( tid, VgSrc_ExitSyscall );
    VG_(reap_threads)(tid);
 
-   { // Remove the valgrind-specific stuff from the environment so the
-     // child doesn't get vg_preload_core.so, vg_preload_TOOL.so, etc.  
-     // This is done unconditionally, since if we are tracing the child,
-     // stage1/2 will set up the appropriate client environment.
-     Char** envp = (Char**)ARG3;
-     if (envp != NULL) {
-        VG_(env_remove_valgrind_env_stuff)( envp );
-     }
+   // Remove the valgrind-specific stuff from the environment so the
+   // child doesn't get vg_preload_core.so, vg_preload_TOOL.so, etc.  
+   // This is done unconditionally, since if we are tracing the child,
+   // stage1/2 will set up the appropriate client environment.
+   envp = VG_(env_clone)( (Char**)ARG3 );
+   if (envp != NULL) {
+      VG_(env_remove_valgrind_env_stuff)( envp );
    }
 
    if (VG_(clo_trace_children)) {
diff --git a/coregrind/pub_core_libcproc.h b/coregrind/pub_core_libcproc.h
index 69afe32565..451539914f 100644
--- a/coregrind/pub_core_libcproc.h
+++ b/coregrind/pub_core_libcproc.h
@@ -70,6 +70,7 @@ extern Char **VG_(env_setenv)   ( Char ***envp, const Char* varname,
                                   const Char *val );
 extern void   VG_(env_unsetenv) ( Char **env, const Char *varname );
 extern void   VG_(env_remove_valgrind_env_stuff) ( Char** env ); 
+extern Char **VG_(env_clone)    ( Char **env_clone );
 
 // misc
 extern Int VG_(poll)( struct vki_pollfd *, UInt nfds, Int timeout);