From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 45E5A3806C6; Sat, 12 Sep 2026 07:15:00 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789197302; cv=none; b=aMozEw3mQucldouLKZtMhK2uBIrydsgLIXMEDJTujZawOu6Hp3/h5/V0caP49hfnlhWghCbwrkPrTPvaWhHTpqfA/vSZ9lsvlYjOHdsdyMplv7/nKaXeHx5dM8WaZjeV1Cev9lFrxBKVqp4QbgvLcWx2zCZR5I6/n9/JfY2pCAU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789197302; c=relaxed/simple; bh=NeJfzOtMfdjXrBTUhAOaKrw3lHkIKWz8S9MVi2kYGQw=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=nrfKy+L77dubsINelaSpsvZ5JLhW6KpoNc+FqKZsqe5tVKaLM7jNY9yJkvC2HprCOjL63ziKqrCblFntpC8NEtQgWjvDdJDTsFt1XDQyor+lZp9C/AxY+jJcF2xyG+SvYDt1MRuX4Sekf1NGRKXS3rFwfHSqdZ0PcLwSViSc9fE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=I2tE0zMz; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="I2tE0zMz" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8D3A61F000FF; Sat, 12 Sep 2026 07:14:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1789197300; bh=PCVCOaobXX4+jkI+acusowJ5IPRJ+MKrIMF1bOe3iEE=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=I2tE0zMzSsaYSc6Or8UYZVjnqFsckE9SGOAkQs+Z6EMcU9JJZBJCRLe+3+7RE8epq osUJV/Le4tzARh3m9kFwJ0LiFA2nTAQtcIuc4SXOlaafev6kYN8w4JOmr7Fi10zuRh /GoRGSDU+LnBjDWhh6J7V0Qta0jGIfLbVsjmQ8d8= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Evgenii Burenchev , "Mario Limonciello (AMD)" , Mario Limonciello , Alex Deucher , Sasha Levin Subject: [PATCH 7.2 0147/1815] drm/amd/display: Fix dangling pointer in plane reset function Date: Sat, 12 Sep 2026 08:31:37 +0200 Message-ID: <20260912065652.467091127@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260912065648.999753832@linuxfoundation.org> References: <20260912065648.999753832@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 7.2-stable review patch. If anyone has any objections, please let me know. ------------------ From: Evgenii Burenchev [ Upstream commit 98cad4bd1443975d972f4c7f705980da03722a22 ] amdgpu_dm_plane_drm_plane_reset() frees the old state before allocating a new one. If kzalloc() 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. Found by Linux Verification Center (linuxtesting.org) with SVACE. Fixes: 5d945cbcd4b1 ("drm/amd/display: Create a file dedicated to planes") Signed-off-by: Evgenii Burenchev Reviewed-by: Mario Limonciello (AMD) Link: https://patch.msgid.link/20260629090435.9729-3-evg28bur@yandex.ru [adjust for movement around current amd-staging-drm-next] Signed-off-by: Mario Limonciello Signed-off-by: Alex Deucher Signed-off-by: Sasha Levin --- .../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_plane.c | 10 ++++------ 1 file changed, 4 insertions(+), 6 deletions(-) diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_plane.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_plane.c index c7f8e08feaf4b..cfd76c54f652b 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_plane.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_plane.c @@ -1488,17 +1488,15 @@ static const struct drm_plane_helper_funcs dm_primary_plane_helper_funcs = { static void amdgpu_dm_plane_drm_plane_reset(struct drm_plane *plane) { - struct dm_plane_state *amdgpu_state = NULL; - - if (plane->state) - plane->funcs->atomic_destroy_state(plane, plane->state); + struct dm_plane_state *amdgpu_state; amdgpu_state = kzalloc_obj(*amdgpu_state); - WARN_ON(amdgpu_state == NULL); - if (!amdgpu_state) return; + if (plane->state) + plane->funcs->atomic_destroy_state(plane, plane->state); + __drm_atomic_helper_plane_reset(plane, &amdgpu_state->base); amdgpu_state->degamma_tf = AMDGPU_TRANSFER_FUNCTION_DEFAULT; amdgpu_state->hdr_mult = AMDGPU_HDR_MULT_DEFAULT; -- 2.53.0