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git-svn-id: svn://svn.valgrind.org/valgrind/trunk@4163

diff --git a/coregrind/m_syswrap/syswrap-generic.c b/coregrind/m_syswrap/syswrap-generic.c
index 42beaed30e8da59b0c489a151e3d61ab5c6dbb49..ec51a40f1cccd47405c88137b580325df9eded79 100644 (file)
--- a/coregrind/m_syswrap/syswrap-generic.c
+++ b/coregrind/m_syswrap/syswrap-generic.c
@@ -2322,6 +2322,8 @@ PRE(sys_execve)
    // 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.
+   // Nb: we make a copy of the environment before trying to mangle it
+   // as it might be in read-only memory (this was bug #101881).
    envp = VG_(env_clone)( (Char**)ARG3 );
    if (envp != NULL) {
       VG_(env_remove_valgrind_env_stuff)( envp );