[Qemu-devel] [PATCH] Fix emulation of splice syscall

[Andreas Schwab]

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.

Signed-off-by: Andreas Schwab <address@hidden>
---
 linux-user/syscall.c | 16 +++++++++++++---
 1 file changed, 13 insertions(+), 3 deletions(-)

diff --git a/linux-user/syscall.c b/linux-user/syscall.c
index d4398b9..db2f5c7 100644
--- a/linux-user/syscall.c
+++ b/linux-user/syscall.c
@@ -9345,14 +9345,24 @@ abi_long do_syscall(void *cpu_env, int num, abi_long 
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
-- 
2.2.2

-- 
Andreas Schwab, SUSE Labs, address@hidden
GPG Key fingerprint = 0196 BAD8 1CE9 1970 F4BE  1748 E4D4 88E3 0EEA B9D7
"And now for something completely different."