Refuse to try mapping zero bytes as this may cause a fault on some configurations / platforms and it seems the prev. attempt is not enough and we need to be more explicit. Signed-off-by: Gilad Ben-Yossef <gilad@xxxxxxxxxxxxx> Reported-by: Corentin Labbe <clabbe.montjoie@xxxxxxxxx> Fixes: ce0fc6db38de ("crypto: ccree - protect against empty or NULL scatterlists") --- drivers/crypto/ccree/cc_buffer_mgr.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/drivers/crypto/ccree/cc_buffer_mgr.c b/drivers/crypto/ccree/cc_buffer_mgr.c index a5e041d9d2cf..11e0278c8631 100644 --- a/drivers/crypto/ccree/cc_buffer_mgr.c +++ b/drivers/crypto/ccree/cc_buffer_mgr.c @@ -258,6 +258,13 @@ static int cc_map_sg(struct device *dev, struct scatterlist *sg, { int ret = 0; + if (!nbytes) { + *mapped_nents = 0; + *lbytes = 0; + *nents = 0; + return 0; + } + *nents = cc_get_sgl_nents(dev, sg, nbytes, lbytes); if (*nents > max_sg_nents) { *nents = 0; -- 2.25.1