On Mon, 25 Jun 2018, Greg Kroah-Hartman wrote: > On Thu, Jun 14, 2018 at 09:29:11PM +0800, Zhouyang Jia wrote: > > When kcalloc fails, the lack of error-handling code may > > cause unexpected results. > > > > This patch adds error-handling code after calling kcalloc. > > > > Signed-off-by: Zhouyang Jia <jiazhouyang09@xxxxxxxxx> > > Acked-by: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx> > > --- > > v1->v2: > > - Remove pr_warn statement. > > --- > > drivers/usb/storage/alauda.c | 3 +++ > > 1 file changed, 3 insertions(+) > > > > diff --git a/drivers/usb/storage/alauda.c b/drivers/usb/storage/alauda.c > > index 900591d..4e17609 100644 > > --- a/drivers/usb/storage/alauda.c > > +++ b/drivers/usb/storage/alauda.c > > @@ -437,6 +437,9 @@ static int alauda_init_media(struct us_data *us) > > + MEDIA_INFO(us).blockshift + MEDIA_INFO(us).pageshift); > > MEDIA_INFO(us).pba_to_lba = kcalloc(num_zones, sizeof(u16*), GFP_NOIO); > > MEDIA_INFO(us).lba_to_pba = kcalloc(num_zones, sizeof(u16*), GFP_NOIO); > > + if ((MEDIA_INFO(us).pba_to_lba == NULL) > > + || (MEDIA_INFO(us).lba_to_pba == NULL)) > > + return USB_STOR_TRANSPORT_ERROR; > > You just leaked memory if only one of these succeeded :( That's not really true. The memory gets deallocated later on in any case, when alauda_info_destructor() calls alauda_free_maps() if not before. More troubling is the fact that this routine (i.e, alauda_init_media) gets called from only one place, in alauda_check_media, and the caller completely ignores the return value! Furthermore, the caller always returns USB_STOR_TRANSPORT_FAILED. So on the whole, I don't think this patch is going to make any difference to the driver's operation. Alan Stern -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
