On Wed, Jun 19, 2013 at 10:12 AM, Serban Constantinescu <[email protected]> wrote: > The Android userspace aligns the data written to the binder buffers to > 4bytes. Thus for 32bit platforms or 64bit platforms running an 32bit > Android userspace we can have a buffer looking like this: > > platform buffer(binder_cmd pointer) size > 32/32 32b 32b 8B > 64/32 32b 64b 12B > 64/64 32b 64b 12B > > Thus the kernel needs to check that the buffer size is aligned to 4bytes > not to (void *) that will be 8bytes on 64bit machines. > > The change does not affect existing 32bit ABI. > > Signed-off-by: Serban Constantinescu <[email protected]> > --- > drivers/staging/android/binder.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/staging/android/binder.c > b/drivers/staging/android/binder.c > index ce70909..7450d56 100644 > --- a/drivers/staging/android/binder.c > +++ b/drivers/staging/android/binder.c > @@ -1247,7 +1247,7 @@ static void binder_transaction_buffer_release(struct > binder_proc *proc, > struct flat_binder_object *fp; > if (*offp > buffer->data_size - sizeof(*fp) || > buffer->data_size < sizeof(*fp) || > - !IS_ALIGNED(*offp, sizeof(void *))) { > + !IS_ALIGNED(*offp, sizeof(u32))) { > pr_err("transaction release %d bad offset %zd, size > %zd\n", > debug_id, *offp, buffer->data_size); > continue; > @@ -1496,7 +1496,7 @@ static void binder_transaction(struct binder_proc *proc, > struct flat_binder_object *fp; > if (*offp > t->buffer->data_size - sizeof(*fp) || > t->buffer->data_size < sizeof(*fp) || > - !IS_ALIGNED(*offp, sizeof(void *))) { > + !IS_ALIGNED(*offp, sizeof(u32))) { > binder_user_error("%d:%d got transaction with invalid > offset, %zd\n", > proc->pid, thread->pid, *offp); > return_error = BR_FAILED_REPLY; > -- > 1.7.9.5 >
Acked-by: Arve Hjønnevåg <[email protected]> -- Arve Hjønnevåg -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
