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 EA12FC433FE for ; Fri, 14 Oct 2022 08:48:20 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 5B76910EAB3; Fri, 14 Oct 2022 08:48:11 +0000 (UTC) Received: from mga04.intel.com (mga04.intel.com [192.55.52.120]) by gabe.freedesktop.org (Postfix) with ESMTPS id 89CE810EAB3 for ; Fri, 14 Oct 2022 08:48:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1665737286; x=1697273286; h=date:from:to:cc:subject:message-id:references: mime-version:in-reply-to; bh=7m3l5eZsKluQ98GTvDHF2LQuTgIiOEZa9D2sn6IOCyM=; b=em/kl8m7W5bkn+8hvuJqKB1ASTBBHPhVSvgkyudSoEpNt/PqothWM7lH wO0ZHP4RPNejgNqL7OcX+kiZ6o1xH8g8im/abrq3NnjtWWZtAVpQLg902 2zN13oNIZnv3+eLKUSBoHDb2ksc70QnOX3KILjUlu8bw+gCpLSUF7Caw7 ICR6+ubaoCCFbsVF73+5jhb1AHlYQOnNyQYmibcu17xs6U89mu9wW/Whl GPKoz7poMzy2AaYCXp0W2qBev96mAMovjZPvXcf/0TosYv1CDnAK8tEau 3yZGcuI2+WvDkaVtFuLxOPh+xdJcTfuok1Yl5/6kANUINUQCOJbzirtvC Q==; X-IronPort-AV: E=McAfee;i="6500,9779,10499"; a="304065847" X-IronPort-AV: E=Sophos;i="5.95,182,1661842800"; d="scan'208";a="304065847" Received: from orsmga006.jf.intel.com ([10.7.209.51]) by fmsmga104.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 14 Oct 2022 01:48:06 -0700 X-IronPort-AV: E=McAfee;i="6500,9779,10499"; a="605303605" X-IronPort-AV: E=Sophos;i="5.95,182,1661842800"; d="scan'208";a="605303605" Received: from mknizews-mobl.ger.corp.intel.com (HELO intel.com) ([10.213.26.40]) by orsmga006-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 14 Oct 2022 01:48:03 -0700 Date: Fri, 14 Oct 2022 10:47:58 +0200 From: Andi Shyti To: Jonathan Cavitt Message-ID: References: <20221013175650.1769399-1-jonathan.cavitt@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20221013175650.1769399-1-jonathan.cavitt@intel.com> Subject: Re: [Intel-gfx] [PATCH] drm/i915/ttm: Fix access_memory null pointer exception X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: intel-gfx@lists.freedesktop.org, matthew.auld@intel.com, andrzej.hajda@intel.com, nirmoy.das@intel.com Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" Hi Jonathan, On Thu, Oct 13, 2022 at 10:56:50AM -0700, Jonathan Cavitt wrote: > i915_ttm_to_gem can return a NULL pointer, which is > dereferenced in i915_ttm_access_memory without first > checking if it is NULL. Inspecting > i915_ttm_io_mem_reserve, it appears the correct > behavior in this case is to return -EINVAL. > > Fixes: 26b15eb0 ("drm/i915/ttm: implement access_memory") > Signed-off-by: Jonathan Cavitt > Suggested-by: John C Harrison > CC: Matthew Auld > CC: Andrzej Hajda > CC: Nirmoy Das > CC: Andi Shyti Reviewed-by: Andi Shyti Thanks, Andi > --- > drivers/gpu/drm/i915/gem/i915_gem_ttm.c | 9 +++++++-- > 1 file changed, 7 insertions(+), 2 deletions(-) > > diff --git a/drivers/gpu/drm/i915/gem/i915_gem_ttm.c b/drivers/gpu/drm/i915/gem/i915_gem_ttm.c > index d63f30efd631..b569624f2ed9 100644 > --- a/drivers/gpu/drm/i915/gem/i915_gem_ttm.c > +++ b/drivers/gpu/drm/i915/gem/i915_gem_ttm.c > @@ -704,11 +704,16 @@ static int i915_ttm_access_memory(struct ttm_buffer_object *bo, > int len, int write) > { > struct drm_i915_gem_object *obj = i915_ttm_to_gem(bo); > - resource_size_t iomap = obj->mm.region->iomap.base - > - obj->mm.region->region.start; > + resource_size_t iomap; > unsigned long page = offset >> PAGE_SHIFT; > unsigned long bytes_left = len; > > + if (!obj) > + return -EINVAL; > + > + iomap = obj->mm.region->iomap.base - > + obj->mm.region->region.start; > + > /* > * TODO: For now just let it fail if the resource is non-mappable, > * otherwise we need to perform the memcpy from the gpu here, without > -- > 2.25.1