Zero out the vki_user_regs_struct before using it. Otherwise, we end

up passing uninitialised garbage on the stack to ptrace(SETREGS, ...)
for any fields in the struct which are not filled in.  This does not
fix any known bugs, but seems like a good precautionary measure.

git-svn-id: svn://svn.valgrind.org/valgrind/trunk@7187

diff --git a/coregrind/m_debugger.c b/coregrind/m_debugger.c
index 2943c398335de3e1d38c2511dc8826ab0a372bd6..346d9e704c57715d73b6b242de5bded93799281b 100644 (file)
--- a/coregrind/m_debugger.c
+++ b/coregrind/m_debugger.c
@@ -49,6 +49,7 @@ static Int ptrace_setregs(Int pid, VexGuestArchState* vex)
 {
 #if defined(VGP_x86_linux)
    struct vki_user_regs_struct regs;
+   VG_(memset)(&regs, 0, sizeof(regs));
    regs.cs     = vex->guest_CS;
    regs.ss     = vex->guest_SS;
    regs.ds     = vex->guest_DS;
@@ -69,6 +70,7 @@ static Int ptrace_setregs(Int pid, VexGuestArchState* vex)
 
 #elif defined(VGP_amd64_linux)
    struct vki_user_regs_struct regs;
+   VG_(memset)(&regs, 0, sizeof(regs));
    regs.rax    = vex->guest_RAX;
    regs.rbx    = vex->guest_RBX;
    regs.rcx    = vex->guest_RCX;