| Message ID | 20211118203712.1288866-1-keescook@chromium.org (mailing list archive) |
|---|---|
| State | Mainlined |
| Commit | 52a0cab35c568f896067641d8e07f798341954f5 |
| Headers | show |
| Series | drbd: Use struct_group() to zero algs | expand |
On Thu, Nov 18, 2021 at 12:37:12PM -0800, Kees Cook wrote: > In preparation for FORTIFY_SOURCE performing compile-time and run-time > field bounds checking for memset(), avoid intentionally writing across > neighboring fields. > > Add a struct_group() for the algs so that memset() can correctly reason > about the size. > > Signed-off-by: Kees Cook <keescook@chromium.org> Reviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org> Thanks -- Gustavo > --- > drivers/block/drbd/drbd_main.c | 3 ++- > drivers/block/drbd/drbd_protocol.h | 6 ++++-- > drivers/block/drbd/drbd_receiver.c | 3 ++- > 3 files changed, 8 insertions(+), 4 deletions(-) > > diff --git a/drivers/block/drbd/drbd_main.c b/drivers/block/drbd/drbd_main.c > index 53ba2dddba6e..feac72e323bd 100644 > --- a/drivers/block/drbd/drbd_main.c > +++ b/drivers/block/drbd/drbd_main.c > @@ -729,7 +729,8 @@ int drbd_send_sync_param(struct drbd_peer_device *peer_device) > cmd = apv >= 89 ? P_SYNC_PARAM89 : P_SYNC_PARAM; > > /* initialize verify_alg and csums_alg */ > - memset(p->verify_alg, 0, 2 * SHARED_SECRET_MAX); > + BUILD_BUG_ON(sizeof(p->algs) != 2 * SHARED_SECRET_MAX); > + memset(&p->algs, 0, sizeof(p->algs)); > > if (get_ldev(peer_device->device)) { > dc = rcu_dereference(peer_device->device->ldev->disk_conf); > diff --git a/drivers/block/drbd/drbd_protocol.h b/drivers/block/drbd/drbd_protocol.h > index dea59c92ecc1..a882b65ab5d2 100644 > --- a/drivers/block/drbd/drbd_protocol.h > +++ b/drivers/block/drbd/drbd_protocol.h > @@ -283,8 +283,10 @@ struct p_rs_param_89 { > > struct p_rs_param_95 { > u32 resync_rate; > - char verify_alg[SHARED_SECRET_MAX]; > - char csums_alg[SHARED_SECRET_MAX]; > + struct_group(algs, > + char verify_alg[SHARED_SECRET_MAX]; > + char csums_alg[SHARED_SECRET_MAX]; > + ); > u32 c_plan_ahead; > u32 c_delay_target; > u32 c_fill_target; > diff --git a/drivers/block/drbd/drbd_receiver.c b/drivers/block/drbd/drbd_receiver.c > index 1f740e42e457..6df2539e215b 100644 > --- a/drivers/block/drbd/drbd_receiver.c > +++ b/drivers/block/drbd/drbd_receiver.c > @@ -3921,7 +3921,8 @@ static int receive_SyncParam(struct drbd_connection *connection, struct packet_i > > /* initialize verify_alg and csums_alg */ > p = pi->data; > - memset(p->verify_alg, 0, 2 * SHARED_SECRET_MAX); > + BUILD_BUG_ON(sizeof(p->algs) != 2 * SHARED_SECRET_MAX); > + memset(&p->algs, 0, sizeof(p->algs)); > > err = drbd_recv_all(peer_device->connection, p, header_size); > if (err) > -- > 2.30.2 > > > >
On Thu, 18 Nov 2021 12:37:12 -0800, Kees Cook wrote: > In preparation for FORTIFY_SOURCE performing compile-time and run-time > field bounds checking for memset(), avoid intentionally writing across > neighboring fields. > > Add a struct_group() for the algs so that memset() can correctly reason > about the size. > > [...] Applied, thanks! [1/1] drbd: Use struct_group() to zero algs commit: 52a0cab35c568f896067641d8e07f798341954f5 Best regards,
diff --git a/drivers/block/drbd/drbd_main.c b/drivers/block/drbd/drbd_main.c index 53ba2dddba6e..feac72e323bd 100644 --- a/drivers/block/drbd/drbd_main.c +++ b/drivers/block/drbd/drbd_main.c @@ -729,7 +729,8 @@ int drbd_send_sync_param(struct drbd_peer_device *peer_device) cmd = apv >= 89 ? P_SYNC_PARAM89 : P_SYNC_PARAM; /* initialize verify_alg and csums_alg */ - memset(p->verify_alg, 0, 2 * SHARED_SECRET_MAX); + BUILD_BUG_ON(sizeof(p->algs) != 2 * SHARED_SECRET_MAX); + memset(&p->algs, 0, sizeof(p->algs)); if (get_ldev(peer_device->device)) { dc = rcu_dereference(peer_device->device->ldev->disk_conf); diff --git a/drivers/block/drbd/drbd_protocol.h b/drivers/block/drbd/drbd_protocol.h index dea59c92ecc1..a882b65ab5d2 100644 --- a/drivers/block/drbd/drbd_protocol.h +++ b/drivers/block/drbd/drbd_protocol.h @@ -283,8 +283,10 @@ struct p_rs_param_89 { struct p_rs_param_95 { u32 resync_rate; - char verify_alg[SHARED_SECRET_MAX]; - char csums_alg[SHARED_SECRET_MAX]; + struct_group(algs, + char verify_alg[SHARED_SECRET_MAX]; + char csums_alg[SHARED_SECRET_MAX]; + ); u32 c_plan_ahead; u32 c_delay_target; u32 c_fill_target; diff --git a/drivers/block/drbd/drbd_receiver.c b/drivers/block/drbd/drbd_receiver.c index 1f740e42e457..6df2539e215b 100644 --- a/drivers/block/drbd/drbd_receiver.c +++ b/drivers/block/drbd/drbd_receiver.c @@ -3921,7 +3921,8 @@ static int receive_SyncParam(struct drbd_connection *connection, struct packet_i /* initialize verify_alg and csums_alg */ p = pi->data; - memset(p->verify_alg, 0, 2 * SHARED_SECRET_MAX); + BUILD_BUG_ON(sizeof(p->algs) != 2 * SHARED_SECRET_MAX); + memset(&p->algs, 0, sizeof(p->algs)); err = drbd_recv_all(peer_device->connection, p, header_size); if (err)
In preparation for FORTIFY_SOURCE performing compile-time and run-time field bounds checking for memset(), avoid intentionally writing across neighboring fields. Add a struct_group() for the algs so that memset() can correctly reason about the size. Signed-off-by: Kees Cook <keescook@chromium.org> --- drivers/block/drbd/drbd_main.c | 3 ++- drivers/block/drbd/drbd_protocol.h | 6 ++++-- drivers/block/drbd/drbd_receiver.c | 3 ++- 3 files changed, 8 insertions(+), 4 deletions(-)