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 A9CE1C433FE for ; Sun, 9 Oct 2022 23:54:41 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id B463310E5B2; Sun, 9 Oct 2022 23:54:39 +0000 (UTC) Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by gabe.freedesktop.org (Postfix) with ESMTPS id DE4FA10E5B1 for ; Sun, 9 Oct 2022 23:54:32 +0000 (UTC) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 66CF260C9B; Sun, 9 Oct 2022 23:54:32 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id AFF0EC433C1; Sun, 9 Oct 2022 23:54:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1665359671; bh=/FwXlzJ9Jrc8DAzVrT3nucKn/N+/4PYuU8ruKXauqMs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=SQr0BlAMxlNGb7JiSr9KT+1cLm1e1D5VANwR6OM/eYM/5Vfyo1zxtZCjZkmpjMZ90 KfUK1FOVgz+OcghEEmNzfZOb+m3Vplp9WurzfZEhSL5WRA1dS58UAZvx5O+ucDVsG7 T5frKe4YhoHXse/J352MxAKUcf8mHhD9HUJ5YGqyIcUXXVj9cAfPDU2kRnD916i/2g +1koX/RiqsHJiP+BcKf62UGyyWtIgx0iOuL4CS4AUCV3mqDgfHTz93RG4w544uWD0r epkL38fmBCNVc3QSKPd2SMWxlBDmHkI+6Xxt03alTJCtVCq2BdySJKeEq7F7Rn6uft S8klhIzx2B63A== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Subject: [PATCH AUTOSEL 5.15 03/25] drm: Prevent drm_copy_field() to attempt copying a NULL pointer Date: Sun, 9 Oct 2022 19:54:03 -0400 Message-Id: <20221009235426.1231313-3-sashal@kernel.org> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20221009235426.1231313-1-sashal@kernel.org> References: <20221009235426.1231313-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit 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: , Cc: Sasha Levin , dri-devel@lists.freedesktop.org, Javier Martinez Canillas , Peter Robinson , Thomas Zimmermann Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" From: Javier Martinez Canillas [ Upstream commit f6ee30407e883042482ad4ad30da5eaba47872ee ] There are some struct drm_driver fields that are required by drivers since drm_copy_field() attempts to copy them to user-space via DRM_IOCTL_VERSION. But it can be possible that a driver has a bug and did not set some of the fields, which leads to drm_copy_field() attempting to copy a NULL pointer: [ +10.395966] Unable to handle kernel access to user memory outside uaccess routines at virtual address 0000000000000000 [ +0.010955] Mem abort info: [ +0.002835] ESR = 0x0000000096000004 [ +0.003872] EC = 0x25: DABT (current EL), IL = 32 bits [ +0.005395] SET = 0, FnV = 0 [ +0.003113] EA = 0, S1PTW = 0 [ +0.003182] FSC = 0x04: level 0 translation fault [ +0.004964] Data abort info: [ +0.002919] ISV = 0, ISS = 0x00000004 [ +0.003886] CM = 0, WnR = 0 [ +0.003040] user pgtable: 4k pages, 48-bit VAs, pgdp=0000000115dad000 [ +0.006536] [0000000000000000] pgd=0000000000000000, p4d=0000000000000000 [ +0.006925] Internal error: Oops: 96000004 [#1] SMP ... [ +0.011113] pstate: 80400005 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ +0.007061] pc : __pi_strlen+0x14/0x150 [ +0.003895] lr : drm_copy_field+0x30/0x1a4 [ +0.004156] sp : ffff8000094b3a50 [ +0.003355] x29: ffff8000094b3a50 x28: ffff8000094b3b70 x27: 0000000000000040 [ +0.007242] x26: ffff443743c2ba00 x25: 0000000000000000 x24: 0000000000000040 [ +0.007243] x23: ffff443743c2ba00 x22: ffff8000094b3b70 x21: 0000000000000000 [ +0.007241] x20: 0000000000000000 x19: ffff8000094b3b90 x18: 0000000000000000 [ +0.007241] x17: 0000000000000000 x16: 0000000000000000 x15: 0000aaab14b9af40 [ +0.007241] x14: 0000000000000000 x13: 0000000000000000 x12: 0000000000000000 [ +0.007239] x11: 0000000000000000 x10: 0000000000000000 x9 : ffffa524ad67d4d8 [ +0.007242] x8 : 0101010101010101 x7 : 7f7f7f7f7f7f7f7f x6 : 6c6e6263606e7141 [ +0.007239] x5 : 0000000000000000 x4 : 0000000000000000 x3 : 0000000000000000 [ +0.007241] x2 : 0000000000000000 x1 : ffff8000094b3b90 x0 : 0000000000000000 [ +0.007240] Call trace: [ +0.002475] __pi_strlen+0x14/0x150 [ +0.003537] drm_version+0x84/0xac [ +0.003448] drm_ioctl_kernel+0xa8/0x16c [ +0.003975] drm_ioctl+0x270/0x580 [ +0.003448] __arm64_sys_ioctl+0xb8/0xfc [ +0.003978] invoke_syscall+0x78/0x100 [ +0.003799] el0_svc_common.constprop.0+0x4c/0xf4 [ +0.004767] do_el0_svc+0x38/0x4c [ +0.003357] el0_svc+0x34/0x100 [ +0.003185] el0t_64_sync_handler+0x11c/0x150 [ +0.004418] el0t_64_sync+0x190/0x194 [ +0.003716] Code: 92402c04 b200c3e8 f13fc09f 5400088c (a9400c02) [ +0.006180] ---[ end trace 0000000000000000 ]--- Reported-by: Peter Robinson Signed-off-by: Javier Martinez Canillas Acked-by: Thomas Zimmermann Link: https://patchwork.freedesktop.org/patch/msgid/20220705100215.572498-3-javierm@redhat.com Signed-off-by: Sasha Levin --- drivers/gpu/drm/drm_ioctl.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/gpu/drm/drm_ioctl.c b/drivers/gpu/drm/drm_ioctl.c index 5669c6cf7135..fb5e6f86dea2 100644 --- a/drivers/gpu/drm/drm_ioctl.c +++ b/drivers/gpu/drm/drm_ioctl.c @@ -474,6 +474,12 @@ static int drm_copy_field(char __user *buf, size_t *buf_len, const char *value) { size_t len; + /* don't attempt to copy a NULL pointer */ + if (WARN_ONCE(!value, "BUG: the value to copy was not set!")) { + *buf_len = 0; + return 0; + } + /* don't overflow userbuf */ len = strlen(value); if (len > *buf_len) -- 2.35.1 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6AC90C433FE for ; Mon, 10 Oct 2022 00:21:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232642AbiJJAVg (ORCPT ); Sun, 9 Oct 2022 20:21:36 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43574 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232419AbiJJAT7 (ORCPT ); Sun, 9 Oct 2022 20:19:59 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8A4FD2A7; Sun, 9 Oct 2022 16:54:34 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 1DF6EB80DEA; Sun, 9 Oct 2022 23:54:33 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id AFF0EC433C1; Sun, 9 Oct 2022 23:54:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1665359671; bh=/FwXlzJ9Jrc8DAzVrT3nucKn/N+/4PYuU8ruKXauqMs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=SQr0BlAMxlNGb7JiSr9KT+1cLm1e1D5VANwR6OM/eYM/5Vfyo1zxtZCjZkmpjMZ90 KfUK1FOVgz+OcghEEmNzfZOb+m3Vplp9WurzfZEhSL5WRA1dS58UAZvx5O+ucDVsG7 T5frKe4YhoHXse/J352MxAKUcf8mHhD9HUJ5YGqyIcUXXVj9cAfPDU2kRnD916i/2g +1koX/RiqsHJiP+BcKf62UGyyWtIgx0iOuL4CS4AUCV3mqDgfHTz93RG4w544uWD0r epkL38fmBCNVc3QSKPd2SMWxlBDmHkI+6Xxt03alTJCtVCq2BdySJKeEq7F7Rn6uft S8klhIzx2B63A== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Javier Martinez Canillas , Peter Robinson , Thomas Zimmermann , Sasha Levin , maarten.lankhorst@linux.intel.com, mripard@kernel.org, airlied@gmail.com, daniel@ffwll.ch, dri-devel@lists.freedesktop.org Subject: [PATCH AUTOSEL 5.15 03/25] drm: Prevent drm_copy_field() to attempt copying a NULL pointer Date: Sun, 9 Oct 2022 19:54:03 -0400 Message-Id: <20221009235426.1231313-3-sashal@kernel.org> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20221009235426.1231313-1-sashal@kernel.org> References: <20221009235426.1231313-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Javier Martinez Canillas [ Upstream commit f6ee30407e883042482ad4ad30da5eaba47872ee ] There are some struct drm_driver fields that are required by drivers since drm_copy_field() attempts to copy them to user-space via DRM_IOCTL_VERSION. But it can be possible that a driver has a bug and did not set some of the fields, which leads to drm_copy_field() attempting to copy a NULL pointer: [ +10.395966] Unable to handle kernel access to user memory outside uaccess routines at virtual address 0000000000000000 [ +0.010955] Mem abort info: [ +0.002835] ESR = 0x0000000096000004 [ +0.003872] EC = 0x25: DABT (current EL), IL = 32 bits [ +0.005395] SET = 0, FnV = 0 [ +0.003113] EA = 0, S1PTW = 0 [ +0.003182] FSC = 0x04: level 0 translation fault [ +0.004964] Data abort info: [ +0.002919] ISV = 0, ISS = 0x00000004 [ +0.003886] CM = 0, WnR = 0 [ +0.003040] user pgtable: 4k pages, 48-bit VAs, pgdp=0000000115dad000 [ +0.006536] [0000000000000000] pgd=0000000000000000, p4d=0000000000000000 [ +0.006925] Internal error: Oops: 96000004 [#1] SMP ... [ +0.011113] pstate: 80400005 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ +0.007061] pc : __pi_strlen+0x14/0x150 [ +0.003895] lr : drm_copy_field+0x30/0x1a4 [ +0.004156] sp : ffff8000094b3a50 [ +0.003355] x29: ffff8000094b3a50 x28: ffff8000094b3b70 x27: 0000000000000040 [ +0.007242] x26: ffff443743c2ba00 x25: 0000000000000000 x24: 0000000000000040 [ +0.007243] x23: ffff443743c2ba00 x22: ffff8000094b3b70 x21: 0000000000000000 [ +0.007241] x20: 0000000000000000 x19: ffff8000094b3b90 x18: 0000000000000000 [ +0.007241] x17: 0000000000000000 x16: 0000000000000000 x15: 0000aaab14b9af40 [ +0.007241] x14: 0000000000000000 x13: 0000000000000000 x12: 0000000000000000 [ +0.007239] x11: 0000000000000000 x10: 0000000000000000 x9 : ffffa524ad67d4d8 [ +0.007242] x8 : 0101010101010101 x7 : 7f7f7f7f7f7f7f7f x6 : 6c6e6263606e7141 [ +0.007239] x5 : 0000000000000000 x4 : 0000000000000000 x3 : 0000000000000000 [ +0.007241] x2 : 0000000000000000 x1 : ffff8000094b3b90 x0 : 0000000000000000 [ +0.007240] Call trace: [ +0.002475] __pi_strlen+0x14/0x150 [ +0.003537] drm_version+0x84/0xac [ +0.003448] drm_ioctl_kernel+0xa8/0x16c [ +0.003975] drm_ioctl+0x270/0x580 [ +0.003448] __arm64_sys_ioctl+0xb8/0xfc [ +0.003978] invoke_syscall+0x78/0x100 [ +0.003799] el0_svc_common.constprop.0+0x4c/0xf4 [ +0.004767] do_el0_svc+0x38/0x4c [ +0.003357] el0_svc+0x34/0x100 [ +0.003185] el0t_64_sync_handler+0x11c/0x150 [ +0.004418] el0t_64_sync+0x190/0x194 [ +0.003716] Code: 92402c04 b200c3e8 f13fc09f 5400088c (a9400c02) [ +0.006180] ---[ end trace 0000000000000000 ]--- Reported-by: Peter Robinson Signed-off-by: Javier Martinez Canillas Acked-by: Thomas Zimmermann Link: https://patchwork.freedesktop.org/patch/msgid/20220705100215.572498-3-javierm@redhat.com Signed-off-by: Sasha Levin --- drivers/gpu/drm/drm_ioctl.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/gpu/drm/drm_ioctl.c b/drivers/gpu/drm/drm_ioctl.c index 5669c6cf7135..fb5e6f86dea2 100644 --- a/drivers/gpu/drm/drm_ioctl.c +++ b/drivers/gpu/drm/drm_ioctl.c @@ -474,6 +474,12 @@ static int drm_copy_field(char __user *buf, size_t *buf_len, const char *value) { size_t len; + /* don't attempt to copy a NULL pointer */ + if (WARN_ONCE(!value, "BUG: the value to copy was not set!")) { + *buf_len = 0; + return 0; + } + /* don't overflow userbuf */ len = strlen(value); if (len > *buf_len) -- 2.35.1