| Message ID | 20200603233203.1695403-3-keescook@chromium.org (mailing list archive) |
|---|---|
| State | Not Applicable, archived |
| Headers | show |
| Series | Remove uninitialized_var() macro | expand |
On Wed, Jun 3, 2020 at 4:32 PM Kees Cook <keescook@chromium.org> wrote: > > Using uninitialized_var() is dangerous as it papers over real bugs[1] > (or can in the future), and suppresses unrelated compiler warnings (e.g. > "unused variable"). If the compiler thinks it is uninitialized, either > simply initialize the variable or make compiler changes. As a precursor > to removing[2] this[3] macro[4], just initialize this variable to NULL. > > [1] https://lore.kernel.org/lkml/20200603174714.192027-1-glider@google.com/ > [2] https://lore.kernel.org/lkml/CA+55aFw+Vbj0i=1TGqCR5vQkCzWJ0QxK6CernOU6eedsudAixw@mail.gmail.com/ > [3] https://lore.kernel.org/lkml/CA+55aFwgbgqhbp1fkxvRKEpzyR5J8n1vKT1VZdz9knmPuXhOeg@mail.gmail.com/ > [4] https://lore.kernel.org/lkml/CA+55aFz2500WfbKXAx8s67wrm9=yVJu65TpLgN_ybYNv0VEOKA@mail.gmail.com/ > > Signed-off-by: Kees Cook <keescook@chromium.org> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Fixes: a29728463b25 ("drbd: Backport the "events2" command") > --- > drivers/block/drbd/drbd_state.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/block/drbd/drbd_state.c b/drivers/block/drbd/drbd_state.c > index eeaa3b49b264..0067d328f0b5 100644 > --- a/drivers/block/drbd/drbd_state.c > +++ b/drivers/block/drbd/drbd_state.c > @@ -1604,7 +1604,7 @@ static void broadcast_state_change(struct drbd_state_change *state_change) > unsigned int n_device, n_connection, n_peer_device, n_peer_devices; > void (*last_func)(struct sk_buff *, unsigned int, void *, > enum drbd_notification_type) = NULL; > - void *uninitialized_var(last_arg); > + void *last_arg = NULL; > > #define HAS_CHANGED(state) ((state)[OLD] != (state)[NEW]) > #define FINAL_STATE_CHANGE(type) \ > -- > 2.25.1 > > -- > You received this message because you are subscribed to the Google Groups "Clang Built Linux" group. > To unsubscribe from this group and stop receiving emails from it, send an email to clang-built-linux+unsubscribe@googlegroups.com. > To view this discussion on the web visit https://groups.google.com/d/msgid/clang-built-linux/20200603233203.1695403-3-keescook%40chromium.org.
diff --git a/drivers/block/drbd/drbd_state.c b/drivers/block/drbd/drbd_state.c index eeaa3b49b264..0067d328f0b5 100644 --- a/drivers/block/drbd/drbd_state.c +++ b/drivers/block/drbd/drbd_state.c @@ -1604,7 +1604,7 @@ static void broadcast_state_change(struct drbd_state_change *state_change) unsigned int n_device, n_connection, n_peer_device, n_peer_devices; void (*last_func)(struct sk_buff *, unsigned int, void *, enum drbd_notification_type) = NULL; - void *uninitialized_var(last_arg); + void *last_arg = NULL; #define HAS_CHANGED(state) ((state)[OLD] != (state)[NEW]) #define FINAL_STATE_CHANGE(type) \
Using uninitialized_var() is dangerous as it papers over real bugs[1] (or can in the future), and suppresses unrelated compiler warnings (e.g. "unused variable"). If the compiler thinks it is uninitialized, either simply initialize the variable or make compiler changes. As a precursor to removing[2] this[3] macro[4], just initialize this variable to NULL. [1] https://lore.kernel.org/lkml/20200603174714.192027-1-glider@google.com/ [2] https://lore.kernel.org/lkml/CA+55aFw+Vbj0i=1TGqCR5vQkCzWJ0QxK6CernOU6eedsudAixw@mail.gmail.com/ [3] https://lore.kernel.org/lkml/CA+55aFwgbgqhbp1fkxvRKEpzyR5J8n1vKT1VZdz9knmPuXhOeg@mail.gmail.com/ [4] https://lore.kernel.org/lkml/CA+55aFz2500WfbKXAx8s67wrm9=yVJu65TpLgN_ybYNv0VEOKA@mail.gmail.com/ Signed-off-by: Kees Cook <keescook@chromium.org> --- drivers/block/drbd/drbd_state.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)