Re: [PATCH] vhost/crypto: fix descriptor processing

[Maxime Coquelin]

On 6/22/22 17:30, David Marchand wrote:

copy_data was returning a pointer to an increased (off by one) descriptor.
Subsequent calls to copy_data in the library were then failing.
Fix this by incrementing the descriptor only if there is some left data
to copy.

Fixes: 7287660a21e0 ("vhost/crypto: fix build with GCC 12")

Reported-by: Jakub Poczatek <jakub.pocza...@intel.com>
Signed-off-by: David Marchand <david.march...@redhat.com>

Reviewed-by: Maxime Coquelin <maxime.coque...@redhat.com>

And also, from discussions on the faulty commit thread, we can add:
Tested-by: Jakub Poczatek <jakub.pocza...@intel.com>

Thanks Jakub for the quick testing,
Maxime

---
  lib/vhost/vhost_crypto.c | 3 +--
  1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/lib/vhost/vhost_crypto.c b/lib/vhost/vhost_crypto.c
index 96ffb82a5d..54946f46d9 100644
--- a/lib/vhost/vhost_crypto.c
+++ b/lib/vhost/vhost_crypto.c
@@ -610,8 +610,7 @@ copy_data(void *data, struct vhost_crypto_data_req *vc_req,
                        return -1;
                left -= copied;
                data = RTE_PTR_ADD(data, copied);
-               desc++;
-       } while (desc < head + max_n_descs && left != 0);
+       } while (left != 0 && ++desc < head + max_n_descs);

if (unlikely(left != 0))

                return -1;