[Qemu-devel] [PATCH v2] linux-user: add getrandom() syscall

[Laurent Vivier]

getrandom() has been introduced in kernel 3.17 and is now used during
the boot sequence of Debian unstable (stretch/sid).

Signed-off-by: Laurent Vivier <address@hidden>
---
v2: fix compilation on AArch64 by conditionally define getrandom()
on TARGET_NR_getrandom AND __NR_getrandom.

 linux-user/syscall.c | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/linux-user/syscall.c b/linux-user/syscall.c
index a051669..5126aac 100644
--- a/linux-user/syscall.c
+++ b/linux-user/syscall.c
@@ -254,6 +254,9 @@ _syscall2(int, ioprio_get, int, which, int, who)
 #if defined(TARGET_NR_ioprio_set) && defined(__NR_ioprio_set)
 _syscall3(int, ioprio_set, int, which, int, who, int, ioprio)
 #endif
+#if defined(TARGET_NR_getrandom) && defined(__NR_getrandom)
+_syscall3(int, getrandom, void *, buf, size_t, buflen, unsigned int, flags)
+#endif
 
 static bitmask_transtbl fcntl_flags_tbl[] = {
   { TARGET_O_ACCMODE,   TARGET_O_WRONLY,    O_ACCMODE,   O_WRONLY,    },
@@ -8234,6 +8237,16 @@ abi_long do_syscall(void *cpu_env, int num, abi_long 
arg1,
         ret = get_errno(shutdown(arg1, arg2));
         break;
 #endif
+#if defined(TARGET_NR_getrandom) && defined(__NR_getrandom)
+    case TARGET_NR_getrandom:
+        p = lock_user(VERIFY_WRITE, arg1, arg2, 0);
+        if (!p) {
+            goto efault;
+        }
+        ret = get_errno(getrandom(p, arg2, arg3));
+        unlock_user(p, arg1, ret);
+        break;
+#endif
 #ifdef TARGET_NR_socket
     case TARGET_NR_socket:
         ret = do_socket(arg1, arg2, arg3);
-- 
2.5.0