Fix emulation of splice syscall

The second and fourth argument are in/out parameters, store them back
after the syscall.  Also, the fourth argument was mishandled, and EFAULT
handling was missing.

Change-Id: I625ecd4dc3e53b8025585727439f1112c38d1758
Patch-Url: https://www.mail-archive.com/qemu-devel@nongnu.org/msg277687.html
Signed-off-by: Stephane Desneux <stephane.desneux@open.eurogiciel.org>

diff --git a/linux-user/syscall.c b/linux-user/syscall.c
index a08f5ef..52885ab 100644 (file)
--- a/linux-user/syscall.c
+++ b/linux-user/syscall.c
@@ -9489,14 +9489,24 @@ abi_long do_syscall(void *cpu_env, int num, abi_ulong arg1,
             loff_t loff_in, loff_out;
             loff_t *ploff_in = NULL, *ploff_out = NULL;
             if(arg2) {
-                get_user_u64(loff_in, arg2);
+                if (get_user_u64(loff_in, arg2))
+                    goto efault;
                 ploff_in = &loff_in;
             }
-            if(arg4) {
-                get_user_u64(loff_out, arg2);
+            if (arg4) {
+                if (get_user_u64(loff_out, arg4))
+                    goto efault;
                 ploff_out = &loff_out;
             }
             ret = get_errno(splice(arg1, ploff_in, arg3, ploff_out, arg5, arg6));
+            if (arg2) {
+                if (put_user_u64(loff_in, arg2))
+                    goto efault;
+            }
+            if (arg4) {
+                if (put_user_u64(loff_out, arg4))
+                    goto efault;
+           }
         }
         break;
 #endif