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 59B52531B0B; Wed, 23 Sep 2026 14:26:16 +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=1790173577; cv=none; b=AygBk6t3x4ZppF3XxxEwCpspAQy1Wg1v+CqmfljJUOvPihemBkT0UC1P6OC8MWRpX4TsSYQZZNremPQH/RE2WnUQqVccT61EqUAsmhHoAinpZm/DHk043CBy503fVMJqnm21TaHAwW0thGsAVBYe5OIE5OK6CVblhCmML5by0n4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790173577; c=relaxed/simple; bh=XIt0UITC05guK+pJBtcboaTWxtX0Ow530YPGjxJEPqc=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=d3auGOSiHGr8C9eUQIJzqbH4u4E+cZEteZEr9LH53eri6LqH6kwPo2MJpteJJKsZ7lz6h/qkT348Fnhbfut1H5Nxc0p3A0y0VXW5IJaWM65XnDhgTgtXrKBtVuoyl82N9r0ElJblM+ZptD29KZRgVlCajoxMNDbXO4NhFZ/X3kw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=EMiQ0oGQ; 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="EMiQ0oGQ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id ADA7F1F00893; Wed, 23 Sep 2026 14:26:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1790173576; bh=PZS5UUAyuquj0mKrlebK5JAIfoe6h/ALEl/Li1muPVc=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=EMiQ0oGQKKNHMFcRrh8pOnj4kxo28FFw/nJATlIK8m4RtBlFBf0LegzUG2DZx1HM3 8q4bluDjjAqbDMrhPb1Vqprj1ydXlRc24AAxCCz1w92Mqfx4slycpduW1yvokWoIHO Erdgn7DeyC47r9TNsvSjlN8AZc0IM6p9ittFbJhc= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Christian Lugnberg , Frank Li , Vinod Koul Subject: [PATCH 7.2 289/438] dmaengine: sun6i: fix undefined behaviour in sun6i_dma_tx_status Date: Wed, 23 Sep 2026 16:05:10 +0200 Message-ID: <20260923140652.267194649@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260923140644.756254324@linuxfoundation.org> References: <20260923140644.756254324@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: Christian Lugnberg commit 9096bdc8d930147f7c39a493a859acbd3a8485d8 upstream. sun6i_dma_tx_status() calls vchan_find_desc() to look up the virtual descriptor for a given cookie, before checking whether the pointer vd is NULL: vd = vchan_find_desc(&vchan->vc, cookie); txd = to_sun6i_desc(&vd->tx); /* vd may be NULL here */ if (vd) { for (lli = txd->v_lli; ...) vchan_find_desc() returns NULL when the descriptor has already been completed or is in-flight on a physical channel and no longer present in the virtual channel's descriptor list. When vd is NULL, to_sun6i_desc() is called unconditionally on &vd->tx before the NULL check, which is undefined behaviour. Move the call inside the if (vd) guard to ensure it is only reached with a valid pointer. vd = vchan_find_desc(&vchan->vc, cookie); if (vd) { struct sun6i_desc *txd = to_sun6i_desc(&vd->tx); for (lli = txd->v_lli; ...) Fixes: 555859308723 ("dmaengine: sun6i: Add driver for the Allwinner A31 DMA controller") Cc: stable@vger.kernel.org Assisted-by: Claude:claude-sonnet-4-6 Signed-off-by: Christian Lugnberg Reviewed-by: Frank Li Link: https://patch.msgid.link/20260817135723.12807-3-christian.lugnberg@soundtrack.io Signed-off-by: Vinod Koul Signed-off-by: Greg Kroah-Hartman --- drivers/dma/sun6i-dma.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) --- a/drivers/dma/sun6i-dma.c +++ b/drivers/dma/sun6i-dma.c @@ -981,7 +981,6 @@ static enum dma_status sun6i_dma_tx_stat struct sun6i_pchan *pchan = vchan->phy; struct sun6i_dma_lli *lli; struct virt_dma_desc *vd; - struct sun6i_desc *txd; enum dma_status ret; unsigned long flags; size_t bytes = 0; @@ -993,9 +992,9 @@ static enum dma_status sun6i_dma_tx_stat spin_lock_irqsave(&vchan->vc.lock, flags); vd = vchan_find_desc(&vchan->vc, cookie); - txd = to_sun6i_desc(&vd->tx); if (vd) { + struct sun6i_desc *txd = to_sun6i_desc(&vd->tx); for (lli = txd->v_lli; lli != NULL; lli = lli->v_lli_next) bytes += lli->len; } else if (!pchan || !pchan->desc) {