From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 7EB58C83F17 for ; Wed, 23 Jul 2025 16:09:29 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id EE28C10E813; Wed, 23 Jul 2025 16:09:28 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=gmail.com header.i=@gmail.com header.b="mPxdatdv"; dkim-atps=neutral Received: from mail-vs1-f45.google.com (mail-vs1-f45.google.com [209.85.217.45]) by gabe.freedesktop.org (Postfix) with ESMTPS id E8BC010E813 for ; Wed, 23 Jul 2025 16:09:26 +0000 (UTC) Received: by mail-vs1-f45.google.com with SMTP id ada2fe7eead31-4ecd5e83bf5so10397137.2 for ; Wed, 23 Jul 2025 09:09:26 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1753286966; x=1753891766; darn=lists.freedesktop.org; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:from:to:cc:subject:date :message-id:reply-to; bh=jiqvICJjX31b+xDIjisgqgN7QHL9poDjF7NeTkSy/Yw=; b=mPxdatdvuzwtPUS28IoVbcI4X6wJ0JdBPFSnYgnu0/1nsqtCzb9tZ0hTJ9HmI0hkO+ NJpTkMbgTElvY1BByAHM+mXvUyiQtBkdb7v8AOojOGovyS8Md2MYG0H4NxbERuVzDmIZ fJppnNfd2Z+uwNJv57D/Le9h01KvcVXz6T1y3RwueqzFkhj4ouSP2kO//KyvJJXckmb4 E0uQl8MkCrU2bZ06UUFb7W+YJMFDsivSISkgNJsLrBeYtzSncW7I78mP73ZRFngHpa5w 17iS8NWtYe6OkxAJ9bZcVsVtkvXpIrWYr7AdD5QPdRxj6dmPVlSZJlkOpjr5ItS1UgGg d2Hw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1753286966; x=1753891766; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=jiqvICJjX31b+xDIjisgqgN7QHL9poDjF7NeTkSy/Yw=; b=SEENvwhwiORQuQZg5bs4vPwmth6VP9dgK/S5TYSUAluOJR9Mf+VEMHXGldckR5CqoK IgVysb57K5FXqlzf8vf9nvFhTPHH17xcOhfv797O/RULoxCwElU5PjCcb1dQAxolv9pd KNQbeMqU6v4APH/j3y1VIhPOirwK224129WeXTFY/KuVyl3sct46ZcRN0xaW59/C7s20 m9Nh1Kj7K8s2QpJsijrPVM8yZbtUsQnEK7uHWfMF2MHV4ae9pay9e15Vf7UZKBg72ruP ubpibrkppODjl1eVgPi3f6C7d3X2P3GieOHDW+Lr2+JGWr97c3OrYrLEk2z+t1tDZ2zS 9ozA== X-Forwarded-Encrypted: i=1; AJvYcCW6oy1UZy0h8Mv9WlWwzwTN4fLQT3gAIxP2zk7uqnmEsWNlv4hv4JuteluUcOpB9ciI+C0h+1ch65A=@lists.freedesktop.org X-Gm-Message-State: AOJu0Yz9hEXY6IwXT3+DZ/X0/ZNPYgvGOl05UCM1tCOYAWCr7Wg3Sk7i owERLdz1HacdpfjWrxT8e4XxoFjmqsm3t2Cz50ZeYrFz6ICVHHsv+oLf+LVxqa3zE5ThKWIjQ0N sWKu7PJyX6YIElpS4YNhQjAo2j22zAw== X-Gm-Gg: ASbGncuVLL2b2jbRfCk9KS8t1Mb3sF885MzO4aQLtVmznufivXpesCrPRSASCaVzBdV G3PMHk43kt3W44UJpOb+OQ/64NQwtZOxZiSQMyMr6TlApVC1KCHatZDPR4pWDJP32+0Qhlo/EgG UO0CvZGbxhbuUaBBbtzo4y+Nhv8OjXIVUxEBz33MqaBPphsmvzPRahYBSd+bCArjUx79UFMREP3 9PFwg== X-Google-Smtp-Source: AGHT+IHLoLIi9Sn5t7UcwQDFfNGKZYmYTYj7fcHTonbPWflJFuRM2pCYd005+IusGSZWW9aDNPoyaalzfB6mYcmmYqg= X-Received: by 2002:a05:6122:d0e:b0:537:3398:e3dc with SMTP id 71dfb90a1353d-537af65b97emr575987e0c.2.1753286965800; Wed, 23 Jul 2025 09:09:25 -0700 (PDT) MIME-Version: 1.0 References: <20250722204114.3340516-1-chenyuan0y@gmail.com> <20250723-gigantic-wrasse-of-warranty-dc70d7@houat> In-Reply-To: <20250723-gigantic-wrasse-of-warranty-dc70d7@houat> From: Chenyuan Yang Date: Wed, 23 Jul 2025 09:09:14 -0700 X-Gm-Features: Ac12FXym4TiBdgoqhdHCo4mS7HgWJgQ8vXuIRZKZN-9W5bm3rxYkRm6h2V9wc34 Message-ID: Subject: Re: [PATCH] drm/bridge: Add null pointer check for ITE IT6263 To: Maxime Ripard Cc: victor.liu@nxp.com, andrzej.hajda@intel.com, neil.armstrong@linaro.org, rfoss@kernel.org, laurent.pinchart@ideasonboard.com, jonas@kwiboo.se, jernej.skrabec@gmail.com, maarten.lankhorst@linux.intel.com, tzimmermann@suse.de, airlied@gmail.com, simona@ffwll.ch, lumag@kernel.org, biju.das.jz@bp.renesas.com, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" Apologies for the second email. I am resending this message as the formatting in the previous version was incorrect On Tue, Jul 22, 2025 at 11:57=E2=80=AFPM Maxime Ripard = wrote: > > On Tue, Jul 22, 2025 at 03:41:14PM -0500, Chenyuan Yang wrote: > > drm_atomic_get_new_connector_for_encoder and > > drm_atomic_get_new_connector_state could return Null. > > They can, but not in that scenario. atomic_enable will never be called > if either would return NULL. > > In which situation did you trigger this bug? This is found by our static analysis tool based on the fact that drm_atomic_get_new_connector_state() could return NULL. We also noticed that under the same dir, the ITE IT6505 transmitter has such checks. Thus, we assume it would be good to have similar checks here. > > Thus, add the null pointer check for them with a similar format with > > it6505_bridge_atomic_enable in ITE IT6505. > > > > Signed-off-by: Chenyuan Yang > > Fixes: 049723628716 ("drm/bridge: Add ITE IT6263 LVDS to HDMI converter= ") > > --- > > drivers/gpu/drm/bridge/ite-it6263.c | 15 ++++++++++++++- > > 1 file changed, 14 insertions(+), 1 deletion(-) > > > > diff --git a/drivers/gpu/drm/bridge/ite-it6263.c b/drivers/gpu/drm/brid= ge/ite-it6263.c > > index a3a63a977b0a..3a20b2088bf9 100644 > > --- a/drivers/gpu/drm/bridge/ite-it6263.c > > +++ b/drivers/gpu/drm/bridge/ite-it6263.c > > @@ -590,15 +590,28 @@ static void it6263_bridge_atomic_enable(struct dr= m_bridge *bridge, > > struct drm_connector *connector; > > bool is_stable =3D false; > > struct drm_crtc *crtc; > > + struct drm_connector_state *conn_state; > > unsigned int val; > > bool pclk_high; > > int i, ret; > > > > connector =3D drm_atomic_get_new_connector_for_encoder(state, > > bridge->enco= der); > > - crtc =3D drm_atomic_get_new_connector_state(state, connector)->cr= tc; > > + if (WARN_ON(!connector)) > > + return; > > + > > + conn_state =3D drm_atomic_get_new_connector_state(state, connecto= r); > > + if (WARN_ON(!conn_state)) > > + return; > > + > > + crtc =3D conn_state->crtc; > > crtc_state =3D drm_atomic_get_new_crtc_state(state, crtc); > > + if (WARN_ON(!crtc_state)) > > + return; > > + > > mode =3D &crtc_state->adjusted_mode; > > + if (WARN_ON(!mode)) > > + return; > > And that condition can never be true. > > Maxime