commit 0fa259dd7986d152294f31a6483272a4cb627b6d
author Giuseppe Musacchio <thatlemon@gmail.com> Mon May 03 19:41:59 2021 +0200
committer Laurent Vivier <laurent@vivier.eu> Tue May 18 07:09:58 2021 +0200
tree 216a407cf9e3455b1228bbda561d4f4e63720054
parent db3221454d6b242c248cc4c33c60b9016e153516

linux-user: Fix erroneous conversion in copy_file_range

The implicit cast from abi_long to size_t may introduce an intermediate
unwanted sign-extension of the value for 32bit targets running on 64bit
hosts.

Signed-off-by: Giuseppe Musacchio <thatlemon@gmail.com>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Message-Id: <20210503174159.54302-3-thatlemon@gmail.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>

linux-user/syscall.c

diff --git a/linux-user/syscall.c b/linux-user/syscall.c
index 4d52b2c..e05870c 100644
--- a/linux-user/syscall.c
+++ b/linux-user/syscall.c
@@ -13244,8 +13244,9 @@
                 }
                 poutoff = &outoff;
             }
+            /* Do not sign-extend the count parameter. */
             ret = get_errno(safe_copy_file_range(arg1, pinoff, arg3, poutoff,
-                                                 arg5, arg6));
+                                                 (abi_ulong)arg5, arg6));
             if (!is_error(ret) && ret > 0) {
                 if (arg2) {
                     if (put_user_u64(inoff, arg2)) {