[libvirt] [PATCHv2] virnetserver: handle sigaction correctly

[Eric Blake]

On 04/19/2012 09:45 PM, Eric Blake wrote:
> POSIX says that sa_sigaction is only safe to use if sa_flags
> includes SA_SIGINFO; conversely, sa_handler is only safe to
> use when flags excludes that bit.  Gnulib doesn't guarantee
> an implementation of SA_SIGINFO, but does guarantee that
> if SA_SIGINFO is undefined, we can safely define it to 0 as
> long as we don't dereference the 2nd or 3rd argument of
> any handler otherwise registered via sa_sigaction.
> 
> Based on a report by Wen Congyang.
> 
> * src/rpc/virnetserver.c (SA_SIGINFO): Stub for mingw.
> (virNetServerSignalHandler): Avoid bogus dereference.
> (virNetServerFatalSignal, virNetServerNew): Set flags properly.
> ---

> +static void
> +virNetServerSignalHandler(int sig, siginfo_t * siginfo ATTRIBUTE_UNUSED,
> +                          void* context ATTRIBUTE_UNUSED)
>  {
>      int origerrno;
>      int r;
> +    siginfo_t tmp;
> +
> +    if (SA_SIGINFO)
> +        tmp = *siginfo;
> +    else
> +        memset(&tmp, 0, sizeof(tmp));
> 
>      /* set the sig num in the struct */
> -    siginfo->si_signo = sig;
> +    tmp->si_signo = sig;

I typo'd that (serves me right for sending before one last compile
test); it should be tmp.si_signo.

-- 
Eric Blake   eblake at redhat.com    +1-919-301-3266
Libvirt virtualization library http://libvirt.org

-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 620 bytes
Desc: OpenPGP digital signature
URL: <http://listman.redhat.com/archives/libvir-list/attachments/20120419/2aab745f/attachment-0001.sig>