On 07/02/2018 07:33 AM, Nikolay Shirokovskiy wrote:
> virCopyLastError is intended to be used after last error is set.
> However due to virLastErrorObject failures (very unlikely through
> as thread local error is allocated on first use) we can have zero
> fields in a copy as a result. In particular code field can be set
> to VIR_ERR_OK.
>
> In some places (qemu monitor, qemu agent and qemu migaration code
> for example) we use copy result as a flag and this leads to bugs.
>
> Let's set OOM-like error in copy in case of virLastErrorObject failures.
>
> Signed-off-by: Nikolay Shirokovskiy <nshirokovskiy@xxxxxxxxxxxxx>
> ---
>
> Changes from v1:
> - check @to
> - set OMM error instead of using virErrorGenericFailure
>
> src/util/virerror.c | 16 +++++++++++-----
> 1 file changed, 11 insertions(+), 5 deletions(-)
>
> diff --git a/src/util/virerror.c b/src/util/virerror.c
> index f198f27..737ea92 100644
> --- a/src/util/virerror.c
> +++ b/src/util/virerror.c
> @@ -366,19 +366,25 @@ virSetError(virErrorPtr newerr)
> *
> * One will need to free the result with virResetError()
> *
> - * Returns 0 if no error was found and the error code otherwise and -1 in case
> - * of parameter error.
> + * Returns error code or -1 in case of parameter error.
> */
> int
> virCopyLastError(virErrorPtr to)
> {
> virErrorPtr err = virLastErrorObject();
> +
> + if (!to)
> + return -1;
> +
> /* We can't guarantee caller has initialized it to zero */
> memset(to, 0, sizeof(*to));
> - if (err)
> + if (err) {
> virCopyError(err, to);
> - else
> - virResetError(to);
> + } else {
> + to->code = VIR_ERR_NO_MEMORY;
> + to->domain = VIR_FROM_NONE;
> + to->level = VIR_ERR_ERROR;
Should we do a VIR_FREE(to->message); so that nothing that was there
before somehow remains... I don't think either agent or monitor
"lastError" is reset until Dispose time.
Beyond that, I think this works for this edge/odd/bad case...
Reviewed-by: John Ferlan <jferlan@xxxxxxxxxx>
John
> + }
> return to->code;
> }
>
>
--
libvir-list mailing list
libvir-list@xxxxxxxxxx
https://www.redhat.com/mailman/listinfo/libvir-list
