From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:38560) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gP9PZ-0000IO-OL for qemu-devel@nongnu.org; Tue, 20 Nov 2018 12:02:06 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1gP9PV-00083s-Mu for qemu-devel@nongnu.org; Tue, 20 Nov 2018 12:02:05 -0500 References: <20181120152753.10463-1-marcandre.lureau@redhat.com> <20181120152753.10463-3-marcandre.lureau@redhat.com> From: Eric Blake Message-ID: <03454b5c-f889-9401-f502-5b14eaab40c8@redhat.com> Date: Tue, 20 Nov 2018 11:01:24 -0600 MIME-Version: 1.0 In-Reply-To: <20181120152753.10463-3-marcandre.lureau@redhat.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: quoted-printable Subject: Re: [Qemu-devel] [PATCH for-3.1? 2/3] migration: fix stringop-truncation warning List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: =?UTF-8?Q?Marc-Andr=c3=a9_Lureau?= , qemu-devel@nongnu.org Cc: Kevin Wolf , qemu-block@nongnu.org, Juan Quintela , Jeff Cody , "Michael S. Tsirkin" , "Dr. David Alan Gilbert" , Max Reitz , Igor Mammedov , Liu Yuan On 11/20/18 9:27 AM, Marc-Andr=C3=A9 Lureau wrote: > Adding an assert is enough to silence GCC. >=20 > ~/src/qemu/migration/global_state.c: In function 'global_state_store_ru= nning': > ~/src/qemu/migration/global_state.c:45:5: error: 'strncpy' specified bo= und 100 equals destination size [-Werror=3Dstringop-truncation] > strncpy((char *)global_state.runstate, > ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > state, sizeof(global_state.runstate)); > ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > cc1: all warnings being treated as errors >=20 > (alternatively, we could hard-code "running") >=20 > Signed-off-by: Marc-Andr=C3=A9 Lureau > --- > migration/global_state.c | 1 + > 1 file changed, 1 insertion(+) Reviewed-by: Eric Blake I think this is safe for 3.1, but I know the migration code is=20 particularly wary of assert()s, even when they are non-triggerable (a=20 100-byte buffer at global_state.runstate is big enough for ALL of the=20 run states, not just RUN_STATE_RUNNING). >=20 > diff --git a/migration/global_state.c b/migration/global_state.c > index 8e8ab5c51e..01805c567a 100644 > --- a/migration/global_state.c > +++ b/migration/global_state.c > @@ -42,6 +42,7 @@ int global_state_store(void) > void global_state_store_running(void) > { > const char *state =3D RunState_str(RUN_STATE_RUNNING); > + assert(strlen(state) < sizeof(global_state.runstate)); > strncpy((char *)global_state.runstate, > state, sizeof(global_state.runstate)); > } >=20 --=20 Eric Blake, Principal Software Engineer Red Hat, Inc. +1-919-301-3266 Virtualization: qemu.org | libvirt.org