diff mbox series

[v3,11/27] linux-user/x86_64: Raise SIGSEGV if SA_RESTORER not set

Message ID 20210924165926.752809-12-richard.henderson@linaro.org (mailing list archive)
State New, archived
Headers show
Series linux-user: Move signal trampolines to new page | expand

Commit Message

Richard Henderson Sept. 24, 2021, 4:59 p.m. UTC 
This has been a fixme for some time.  The effect of
returning -EFAULT from the kernel code is to raise SIGSEGV.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
 linux-user/i386/signal.c | 11 +++++------
 1 file changed, 5 insertions(+), 6 deletions(-)

Comments

Peter Maydell Sept. 27, 2021, 1:01 p.m. UTC | #1 
On Fri, 24 Sept 2021 at 17:59, Richard Henderson
<richard.henderson@linaro.org> wrote:
>
> This has been a fixme for some time.  The effect of
> returning -EFAULT from the kernel code is to raise SIGSEGV.
>
> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
> ---

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>

thanks
-- PMM
diff mbox series

Patch

diff --git a/linux-user/i386/signal.c b/linux-user/i386/signal.c
index 94ab6396a0..55a36476d1 100644
--- a/linux-user/i386/signal.c
+++ b/linux-user/i386/signal.c
@@ -421,19 +421,18 @@  void setup_rt_frame(int sig, struct target_sigaction *ka,
 
     /* Set up to return from userspace.  If provided, use a stub
        already in userspace.  */
-#ifndef TARGET_X86_64
     if (ka->sa_flags & TARGET_SA_RESTORER) {
         __put_user(ka->sa_restorer, &frame->pretcode);
     } else {
+#ifdef TARGET_X86_64
+        /* For x86_64, SA_RESTORER is required ABI.  */
+        goto give_sigsegv;
+#else
         /* This is no longer used, but is retained for ABI compatibility. */
         install_rt_sigtramp(frame->retcode);
         __put_user(default_rt_sigreturn, &frame->pretcode);
-    }
-#else
-    /* XXX: Would be slightly better to return -EFAULT here if test fails
-       assert(ka->sa_flags & TARGET_SA_RESTORER); */
-    __put_user(ka->sa_restorer, &frame->pretcode);
 #endif
+    }
 
     /* Set up registers for signal handler */
     env->regs[R_ESP] = frame_addr;