Re: [Qemu-devel] [Qemu-block] [PATCH for-2.6] crypto: Avoid memory leak on failure

[Max Reitz <mreitz@redhat.com>]

[-- Attachment #1.1: Type: text/plain, Size: 1057 bytes --]

On 01.04.2016 17:57, Eric Blake wrote:
> Commit 7836857 introduced a memory leak due to invalid use of
> Error vs. visit_type_end().  If visiting the intermediate
> members fails, we clear the error and unconditionally use
> visit_end_struct() on the same error object; but if that
> cleanup succeeds, we then skip the qapi_free call.

It's not really a memleak. Due to skipping those conditional branches
after the "out" label, a non-null value will be returned. In order to
determine whether the function call failed, the callers of these
functions do not use the errp value but the return value. Therefore,
they will think the call succeeded when actually it did not.

> 
> Until a later patch adds visit_check_struct(), the only safe
> approach is to use two separate error objects.
> 
> Signed-off-by: Eric Blake <eblake@redhat.com>
> ---
>  block/crypto.c | 12 ++++++------
>  1 file changed, 6 insertions(+), 6 deletions(-)

Anyway, thanks, applied to my block branch:

https://github.com/XanClic/qemu/commits/block

Max


[-- Attachment #2: OpenPGP digital signature --]
[-- Type: application/pgp-signature, Size: 473 bytes --]