From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from forward100d.mail.yandex.net (forward100d.mail.yandex.net [178.154.239.211]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id CFF693F0747; Mon, 29 Jun 2026 09:11:15 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=178.154.239.211 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782724277; cv=none; b=S/GgI26vGzMBrlaKeqs0xoPPfR4M8pqs+LqumKuTuXtpt0El0dePQ6itY9SeLwPIFDLb3emKRqKoxcdxGhRRjM4upuyyxszBRNbvLM/zLEgsq7MHrxOyZR98rZKejuxrKOQai2BOd6Q2iOKAkeRcLG5XiTRhU/jufKtfdOyvrgI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782724277; c=relaxed/simple; bh=OxAfcyH+8Zv1fFuZDzh0c3Nh09c0gOk2dNXllQCCaxc=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=rhtzXwAfljuccDfE36AwOKV9E0SBh3HfrsRN9eAgIu3231sIAPpRDlhsUGdrwIMvxr6ZHIBPjjpwjWpGxc9BY6HN5s40Wt5XkZGI4fBOlFSd+xDzL1akn32wQsQ2jse05faSlIu6OY6pwgVgj7ubE+a8Usmc2N2LbuTz2+1xnPU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=yandex.ru; spf=pass smtp.mailfrom=yandex.ru; dkim=pass (1024-bit key) header.d=yandex.ru header.i=@yandex.ru header.b=oFEeQzkK; arc=none smtp.client-ip=178.154.239.211 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=yandex.ru Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=yandex.ru Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=yandex.ru header.i=@yandex.ru header.b="oFEeQzkK" Received: from mail-nwsmtp-smtp-production-main-73.iva.yp-c.yandex.net (mail-nwsmtp-smtp-production-main-73.iva.yp-c.yandex.net [IPv6:2a02:6b8:c0c:bb8b:0:640:6ac7:0]) by forward100d.mail.yandex.net (postfix) with ESMTPS id D4A69C00F9; Mon, 29 Jun 2026 12:11:07 +0300 (MSK) Received: by mail-nwsmtp-smtp-production-main-73.iva.yp-c.yandex.net (smtp) with ESMTPSA id ZAZXGGsiDOs0-SYImwU3y; Mon, 29 Jun 2026 12:11:06 +0300 X-Yandex-Fwd: 1 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=yandex.ru; s=mail; t=1782724266; bh=sM6D1HOqQeLKlOUIzQLXH1KXbMCFiNY+40aRY6mi29w=; h=Message-ID:Date:In-Reply-To:Cc:Subject:References:To:From; b=oFEeQzkKKDg2nhmtrxaFqL4852a639s7Ts1woroD9xE/zhNNnF9HDiEQ5/f3CkZHc xJvdTg3+k9RBR+I/FXG040mgTNws4BKM7LoceYpE4ZyXobGmqK3+IEZTymrp9SIGHH ZufbMbECzuPkDrasku8yNbM4DbKK4k8uVi/wDfRA= Authentication-Results: mail-nwsmtp-smtp-production-main-73.iva.yp-c.yandex.net; dkim=pass header.i=@yandex.ru From: Evgenii Burenchev To: stable@vger.kernel.org, Greg Kroah-Hartman Cc: Evgenii Burenchev , harry.wentland@amd.com, sunpeng.li@amd.com, siqueira@igalia.com, alexander.deucher@amd.com, christian.koenig@amd.com, airlied@gmail.com, simona@ffwll.ch, mario.limonciello@amd.com, alex.hung@amd.com, superm1@kernel.org, timur.kristof@gmail.com, ivan.lipski@amd.com, ray.wu@amd.com, aurabindo.pillai@amd.com, chen-yu.chen@amd.com, mripard@kernel.org, Dillon.Varone@amd.com, mwen@igalia.com, chiahsuan.chung@amd.com, kenneth.feng@amd.com, srinivasan.shanmugam@amd.com, tzimmermann@suse.de, Alvin.Lee2@amd.com, dmitry.baryshkov@oss.qualcomm.com, chaitanya.kumar.borah@intel.com, ekurzinger@gmail.com, pierre-eric.pelloux-prayer@amd.com, HaoPing.Liu@amd.com, Tony.Cheng@amd.com, amd-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, lvc-project@linuxtesting.org Subject: [PATCH v4 3/3] drm/amd/display: Fix dangling pointer in connector reset function Date: Mon, 29 Jun 2026 12:04:31 +0300 Message-ID: <20260629090435.9729-5-evg28bur@yandex.ru> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260629090435.9729-2-evg28bur@yandex.ru> References: <20260629090435.9729-2-evg28bur@yandex.ru> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit amdgpu_dm_connector_funcs_reset() frees the old state before allocating a new one. If kzalloc_obj() fails, the function returns without updating the state pointer, leaving a dangling pointer to already freed memory. Fix this by allocating the new state first. On allocation failure, the old state remains untouched and the function safely returns. Additionally restore the explicit kfree(old_state) which was lost when the function was refactored, as __drm_atomic_helper_connector_destroy_state() only frees resources but not the state structure itself. Fixes: e7b07ceef2a6 ("drm/amd/display: Merge amdgpu_dm_types and amdgpu_dm") Signed-off-by: Evgenii Burenchev --- .../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 39 ++++++++++--------- 1 file changed, 20 insertions(+), 19 deletions(-) diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c index d3a8d681227a..b1f91dd0ab61 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c @@ -8151,33 +8151,34 @@ static void amdgpu_dm_connector_destroy(struct drm_connector *connector) void amdgpu_dm_connector_funcs_reset(struct drm_connector *connector) { - struct dm_connector_state *state = + struct dm_connector_state *old_state = to_dm_connector_state(connector->state); + struct dm_connector_state *state; + + state = kzalloc_obj(*state); + if (!state) + return; if (connector->state) __drm_atomic_helper_connector_destroy_state(connector->state); - kfree(state); + kfree(old_state); - state = kzalloc_obj(*state); + __drm_atomic_helper_connector_reset(connector, &state->base); - if (state) { - state->scaling = RMX_OFF; - state->underscan_enable = false; - state->underscan_hborder = 0; - state->underscan_vborder = 0; - state->base.max_requested_bpc = 8; - state->vcpi_slots = 0; - state->pbn = 0; - - if (connector->connector_type == DRM_MODE_CONNECTOR_eDP) { - if (amdgpu_dm_abm_level <= 0) - state->abm_level = ABM_LEVEL_IMMEDIATE_DISABLE; - else - state->abm_level = amdgpu_dm_abm_level; - } + state->scaling = RMX_OFF; + state->underscan_enable = false; + state->underscan_hborder = 0; + state->underscan_vborder = 0; + state->base.max_requested_bpc = 8; + state->vcpi_slots = 0; + state->pbn = 0; - __drm_atomic_helper_connector_reset(connector, &state->base); + if (connector->connector_type == DRM_MODE_CONNECTOR_eDP) { + if (amdgpu_dm_abm_level <= 0) + state->abm_level = ABM_LEVEL_IMMEDIATE_DISABLE; + else + state->abm_level = amdgpu_dm_abm_level; } } -- 2.43.0