linux-user: fix do_rt_sigreturn on m68k linux userspace emulation

do_rt_sigreturn uses an uninitialised local variable instead of fetching
the old signal mask directly from the signal frame when restoring the mask,
so the signal mask is undefined after do_rt_sigreturn. As the signal
frame data is in target-endian order, target_to_host_sigset instead of
target_to_host_sigset_internal is required.

do_sigreturn is correct in using target_to_host_sigset_internal, because
get_user already did the endianness conversion.

Signed-off-by: Michael Karcher <karcher@physik.fu-berlin.de>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Message-Id: <20170225110517.2832-3-laurent@vivier.eu>

diff --git a/linux-user/signal.c b/linux-user/signal.c
index 99adfc29e4f29d4ec5c949d4b4d4fcf34a382a13..a67db04e1a48c5f354d449c9387af5a6749d0f9e 100644 (file)
--- a/linux-user/signal.c
+++ b/linux-user/signal.c
@@ -5851,14 +5851,13 @@ long do_rt_sigreturn(CPUM68KState *env)
 {
     struct target_rt_sigframe *frame;
     abi_ulong frame_addr = env->aregs[7] - 4;
-    target_sigset_t target_set;
     sigset_t set;
 
     trace_user_do_rt_sigreturn(env, frame_addr);
     if (!lock_user_struct(VERIFY_READ, frame, frame_addr, 1))
         goto badframe;
 
-    target_to_host_sigset_internal(&set, &target_set);
+    target_to_host_sigset(&set, &frame->uc.tuc_sigmask);
     set_sigmask(&set);
 
     /* restore registers */