block/vhdx: Don't take address of fields in packed structs

Taking the address of a field in a packed struct is a bad idea, because
it might not be actually aligned enough for that pointer type (and
thus cause a crash on dereference on some host architectures). Newer
versions of clang warn about this. Avoid the bug by not using the
"modify in place" byte swapping functions.

There are a few places where the in-place swap function is
used on something other than a packed struct field; we convert
those anyway, for consistency.

Patch produced with scripts/coccinelle/inplace-byteswaps.cocci.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

1 files changed, 2 insertions, 2 deletions

diff --git a/block/vhdx-log.c b/block/vhdx-log.c
index d2f1b98..ecd6426 100644
--- a/block/vhdx-log.c
+++ b/block/vhdx-log.c
@@ -835,11 +835,11 @@ static void vhdx_log_raw_to_le_sector(VHDXLogDescriptor *desc,
     /* 8 + 4084 + 4 = 4096, 1 log sector */
     memcpy(&desc->leading_bytes, data, 8);
     data += 8;
-    cpu_to_le64s(&desc->leading_bytes);
+    desc->leading_bytes = cpu_to_le64(desc->leading_bytes);
     memcpy(sector->data, data, 4084);
     data += 4084;
     memcpy(&desc->trailing_bytes, data, 4);
-    cpu_to_le32s(&desc->trailing_bytes);
+    desc->trailing_bytes = cpu_to_le32(desc->trailing_bytes);
     data += 4;
 
     sector->sequence_high  = (uint32_t) (seq >> 32);