From: Kevin Wolf <m...@kevin-wolf.de> Allocation and deallocation of bs->opaque is not in the control of a block driver. Therefore it should not set bs->opaque to a data structure used by another bs, or closing the image will lead to a double free.
Signed-off-by: Kevin Wolf <m...@kevin-wolf.de> --- block/vvfat.c | 7 ++++--- 1 files changed, 4 insertions(+), 3 deletions(-) diff --git a/block/vvfat.c b/block/vvfat.c index 5898d66..0772037 100644 --- a/block/vvfat.c +++ b/block/vvfat.c @@ -2768,12 +2768,12 @@ static int vvfat_is_allocated(BlockDriverState *bs, static int write_target_commit(BlockDriverState *bs, int64_t sector_num, const uint8_t* buffer, int nb_sectors) { - BDRVVVFATState* s = bs->opaque; + BDRVVVFATState* s = *((BDRVVVFATState**) bs->opaque); return try_commit(s); } static void write_target_close(BlockDriverState *bs) { - BDRVVVFATState* s = bs->opaque; + BDRVVVFATState* s = *((BDRVVVFATState**) bs->opaque); bdrv_delete(s->qcow); free(s->qcow_filename); } @@ -2816,7 +2816,8 @@ static int enable_write_target(BDRVVVFATState *s) s->bs->backing_hd = calloc(sizeof(BlockDriverState), 1); s->bs->backing_hd->drv = &vvfat_write_target; - s->bs->backing_hd->opaque = s; + s->bs->backing_hd->opaque = qemu_malloc(sizeof(void*)); + *(void**)s->bs->backing_hd->opaque = s; return 0; } -- 1.7.2.2