On Fri, Feb 01, 2019 at 04:30:12PM +0000, Will Deacon wrote:
> On Thu, Jan 17, 2019 at 01:40:14PM +0100, Anisse Astier wrote:
> > GCC 8.2 gives this warning:
> >
> > virtio/9p.c: In function ‘virtio_p9_create’:
> > virtio/9p.c:335:21: error: passing argument 1 to restrict-qualified parameter aliases with argument 4 [-Werror=restrict]
> > ret = snprintf(dfid->path, size, "%s/%s", dfid->path, name);
> > ~~~~^~~~~~ ~~~~~~~~~~
> >
> > Fix it by allocating a temporary string with dfid->path content instead
> > of overwriting it in-place, which is limited in glibc snprintf with the
> > __restrict qualifier.
> >
> > Signed-off-by: Anisse Astier <aastier@xxxxxxxxxx>
> > ---
> > virtio/9p.c | 9 ++++++++-
> > 1 file changed, 8 insertions(+), 1 deletion(-)
> >
> > diff --git a/virtio/9p.c b/virtio/9p.c
> > index 69fdc4b..6ae1999 100644
> > --- a/virtio/9p.c
> > +++ b/virtio/9p.c
> > @@ -322,6 +322,7 @@ static void virtio_p9_create(struct p9_dev *p9dev,
> > struct p9_qid qid;
> > struct p9_fid *dfid;
> > char full_path[PATH_MAX];
> > + char *tmp_path;
> > u32 dfid_val, flags, mode, gid;
> >
> > virtio_p9_pdu_readf(pdu, "dsddd", &dfid_val,
> > @@ -332,7 +333,13 @@ static void virtio_p9_create(struct p9_dev *p9dev,
> > goto err_out;
> >
> > size = sizeof(dfid->abs_path) - (dfid->path - dfid->abs_path);
> > - ret = snprintf(dfid->path, size, "%s/%s", dfid->path, name);
> > + tmp_path = strdup(dfid->path);
> > + if (!tmp_path) {
> > + errno = ENOMEM;
>
> Won't errno already be set by the failing strdup?
>
> Will
Indeed, I didn't know it would. I'll send an updated version.
Thanks,
Anisse
