From 091901841af285f963ea80cd18d616fd0350ddbc Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Tue, 16 Oct 2018 18:25:03 +0100 Subject: [PATCH] block/vdi: 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. There are other places where we take the address of a packed member in this file for other purposes than passing it to a byteswap function (all the calls to qemu_uuid_*()); we leave those for now. Signed-off-by: Peter Maydell Reviewed-by: Stefan Hajnoczi Signed-off-by: Kevin Wolf --- block/vdi.c | 64 ++++++++++++++++++++++++++--------------------------- 1 file changed, 32 insertions(+), 32 deletions(-) diff --git a/block/vdi.c b/block/vdi.c index 6555cffb88..0ff1ead736 100644 --- a/block/vdi.c +++ b/block/vdi.c @@ -187,22 +187,22 @@ typedef struct { static void vdi_header_to_cpu(VdiHeader *header) { - le32_to_cpus(&header->signature); - le32_to_cpus(&header->version); - le32_to_cpus(&header->header_size); - le32_to_cpus(&header->image_type); - le32_to_cpus(&header->image_flags); - le32_to_cpus(&header->offset_bmap); - le32_to_cpus(&header->offset_data); - le32_to_cpus(&header->cylinders); - le32_to_cpus(&header->heads); - le32_to_cpus(&header->sectors); - le32_to_cpus(&header->sector_size); - le64_to_cpus(&header->disk_size); - le32_to_cpus(&header->block_size); - le32_to_cpus(&header->block_extra); - le32_to_cpus(&header->blocks_in_image); - le32_to_cpus(&header->blocks_allocated); + header->signature = le32_to_cpu(header->signature); + header->version = le32_to_cpu(header->version); + header->header_size = le32_to_cpu(header->header_size); + header->image_type = le32_to_cpu(header->image_type); + header->image_flags = le32_to_cpu(header->image_flags); + header->offset_bmap = le32_to_cpu(header->offset_bmap); + header->offset_data = le32_to_cpu(header->offset_data); + header->cylinders = le32_to_cpu(header->cylinders); + header->heads = le32_to_cpu(header->heads); + header->sectors = le32_to_cpu(header->sectors); + header->sector_size = le32_to_cpu(header->sector_size); + header->disk_size = le64_to_cpu(header->disk_size); + header->block_size = le32_to_cpu(header->block_size); + header->block_extra = le32_to_cpu(header->block_extra); + header->blocks_in_image = le32_to_cpu(header->blocks_in_image); + header->blocks_allocated = le32_to_cpu(header->blocks_allocated); qemu_uuid_bswap(&header->uuid_image); qemu_uuid_bswap(&header->uuid_last_snap); qemu_uuid_bswap(&header->uuid_link); @@ -211,22 +211,22 @@ static void vdi_header_to_cpu(VdiHeader *header) static void vdi_header_to_le(VdiHeader *header) { - cpu_to_le32s(&header->signature); - cpu_to_le32s(&header->version); - cpu_to_le32s(&header->header_size); - cpu_to_le32s(&header->image_type); - cpu_to_le32s(&header->image_flags); - cpu_to_le32s(&header->offset_bmap); - cpu_to_le32s(&header->offset_data); - cpu_to_le32s(&header->cylinders); - cpu_to_le32s(&header->heads); - cpu_to_le32s(&header->sectors); - cpu_to_le32s(&header->sector_size); - cpu_to_le64s(&header->disk_size); - cpu_to_le32s(&header->block_size); - cpu_to_le32s(&header->block_extra); - cpu_to_le32s(&header->blocks_in_image); - cpu_to_le32s(&header->blocks_allocated); + header->signature = cpu_to_le32(header->signature); + header->version = cpu_to_le32(header->version); + header->header_size = cpu_to_le32(header->header_size); + header->image_type = cpu_to_le32(header->image_type); + header->image_flags = cpu_to_le32(header->image_flags); + header->offset_bmap = cpu_to_le32(header->offset_bmap); + header->offset_data = cpu_to_le32(header->offset_data); + header->cylinders = cpu_to_le32(header->cylinders); + header->heads = cpu_to_le32(header->heads); + header->sectors = cpu_to_le32(header->sectors); + header->sector_size = cpu_to_le32(header->sector_size); + header->disk_size = cpu_to_le64(header->disk_size); + header->block_size = cpu_to_le32(header->block_size); + header->block_extra = cpu_to_le32(header->block_extra); + header->blocks_in_image = cpu_to_le32(header->blocks_in_image); + header->blocks_allocated = cpu_to_le32(header->blocks_allocated); qemu_uuid_bswap(&header->uuid_image); qemu_uuid_bswap(&header->uuid_last_snap); qemu_uuid_bswap(&header->uuid_link);