See commit b317006a3f1 ("docs/secure-coding-practices: Describe how
to use 'null-co' block driver") for rationale.
Signed-off-by: Philippe Mathieu-Daudé <phi...@redhat.com>
---
block/null.c | 8 ++++++++
1 file changed, 8 insertions(+)
diff --git a/block/null.c b/block/null.c
index cc9b1d4ea72..11e428f3cc2 100644
--- a/block/null.c
+++ b/block/null.c
@@ -99,6 +99,13 @@ static int null_file_open(BlockDriverState *bs, QDict
*options, int flags,
return ret;
}
+static bool null_taints_security_policy(BlockDriverState *bs)
+{
+ BDRVNullState *s = bs->opaque;
+
+ return !s->read_zeroes;
+}
+
static int64_t null_getlength(BlockDriverState *bs)
{
BDRVNullState *s = bs->opaque;
@@ -283,6 +290,7 @@ static BlockDriver bdrv_null_co = {
.bdrv_parse_filename = null_co_parse_filename,
.bdrv_getlength = null_getlength,
.bdrv_get_allocated_file_size = null_allocated_file_size,
+ .bdrv_taints_security_policy = null_taints_security_policy,
.bdrv_co_preadv = null_co_preadv,
.bdrv_co_pwritev = null_co_pwritev,
--
2.31.1
