linux-user: fix statfs

The statfs syscall should always memset(0) its full struct extent before
writing to it. Newer versions of the syscall use one of the reserved fields
for flags, which would otherwise get stale values from uncleaned memory.

This fixes libarchive for me, which got confused about the return value of
pathconf("/", _PC_REC_XFER_ALIGN) otherwise, as it some times gave old pointers
as return value.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>

diff --git a/linux-user/syscall.c b/linux-user/syscall.c
index 471d0605f7a5b8ba2471a6a6678986d5a01194e0..1a381699ef1124a2e6586289832a34907bb40cec 100644 (file)
--- a/linux-user/syscall.c
+++ b/linux-user/syscall.c
@@ -6529,6 +6529,8 @@ abi_long do_syscall(void *cpu_env, int num, abi_long arg1,
             __put_user(stfs.f_fsid.__val[0], &target_stfs->f_fsid.val[0]);
             __put_user(stfs.f_fsid.__val[1], &target_stfs->f_fsid.val[1]);
             __put_user(stfs.f_namelen, &target_stfs->f_namelen);
+            __put_user(stfs.f_frsize, &target_stfs->f_frsize);
+            memset(target_stfs->f_spare, 0, sizeof(target_stfs->f_spare));
             unlock_user_struct(target_stfs, arg2, 1);
         }
         break;
@@ -6557,6 +6559,8 @@ abi_long do_syscall(void *cpu_env, int num, abi_long arg1,
             __put_user(stfs.f_fsid.__val[0], &target_stfs->f_fsid.val[0]);
             __put_user(stfs.f_fsid.__val[1], &target_stfs->f_fsid.val[1]);
             __put_user(stfs.f_namelen, &target_stfs->f_namelen);
+            __put_user(stfs.f_frsize, &target_stfs->f_frsize);
+            memset(target_stfs->f_spare, 0, sizeof(target_stfs->f_spare));
             unlock_user_struct(target_stfs, arg3, 1);
         }
         break;