From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pj1-f43.google.com (mail-pj1-f43.google.com [209.85.216.43]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 632BD378D9C for ; Sun, 12 Jul 2026 22:00:43 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.216.43 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783893644; cv=none; b=ou+mb0NHD+1G5NwZ1jwcm+yRZdyEvQvc2SKoXRewlNdj8cqCFMGpfjdcUm2wcALlkvkgMq7pkIrby2PCVxc3YDcGbNeOTd6fn4ak/FPxjZJ30H2KPhbBHcgUwLBzb+f/UQnbwJi6CmttqG52hacuTW44x8wJPmHQXRoxhbzxH14= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783893644; c=relaxed/simple; bh=XB/FXyBc5Jaregb9hd8KLGeQNU5RAms9ksjPvVxmUe8=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=tBlgQcosKbIfKvzbJtmBoOYLrJoJh06YkTzGgf7DOai8wKa/5NvbisUWcz9szPKhWhTvE57t2/GxdZjbeGO4xQLYwYbe2WjKGclI4e5Puphwphhp+Gpex8ZZDHSIvQiszUZlPXlokotSdJQbg09xxferwXBgt5eOemMpMMKt5KI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=g68vZbOW; arc=none smtp.client-ip=209.85.216.43 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="g68vZbOW" Received: by mail-pj1-f43.google.com with SMTP id 98e67ed59e1d1-38dfe7eb825so125690a91.0 for ; Sun, 12 Jul 2026 15:00:43 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1783893643; x=1784498443; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to:content-type; bh=RIRKxzKpxKWrf9QwtK6Xlt/4yAtQNiP0hgI5FE3Urag=; b=g68vZbOWHuExJvNrqF7s8VcamZ1I01pKUZTiwYVI2CoqoxJuTVNGxgpngwq8NMWBw8 xoIxA2Zij8YDYCR8I8Ge2ID8JOH8NN0VVpcG/45uaC167DzalqNcNIAoT80SXRph+Ibj smcUIxAYBqbqk21pxF8VHnm//z8Mq1gx0O61lGTpOcxGchQOC6WVjrcIYTt57bgNzHIS 1WUuxczZUjG3GlYV2UFbWf0AMMU7ZHM2kgYCSnvUMd5Lsm2vypn0ZrsejdbO8RoMmPOO tTQecUB0naKAE1l7K4cAu2OK0MkXwUcW+kTdtuEU8ydgx/3gdR0IFqETkSd0l/Bmr2eH dwsQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1783893643; x=1784498443; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-gg:x-gm-message-state:from :to:cc:subject:date:message-id:reply-to:content-type; bh=RIRKxzKpxKWrf9QwtK6Xlt/4yAtQNiP0hgI5FE3Urag=; b=q/qtag0ZhnkBE2RQ/0oKdb88LxIOVjmmkgKUT3XMy/GZYYQE1vlLNCvhDaYCAydqI2 dA9zc5i+ioj4UoRrhmwcTrpuFUlgLWzqLGTt6fPwl07bhQvuGCMk+XW26MBrJWIMnpAi +KnQGj5979SEbdQFSo3cI0nYXMqvQcJv34gvh3xj6xuG4UCIC97uQPAshcsiqM13Ug7s AQvoES5wmHsJrg9UudONH3fV0YZRLLLLvJ+lr6e3NeL4OJSy/UHkkpjBFpZmR+pFicdw N8ZrZSo7MJRp14Bw+h2a297zgCNw2fWccVNFHyaPBLnH89BA7+8vHRhbZhYUcUfZrk82 sXyw== X-Forwarded-Encrypted: i=1; AHgh+Rp/2ZjSaHczG7k1gsBMarKApB8W98+aoWeWBHG9Gckq4E4qT7BYB4b2S137iLYD7F3ljJSxP4qJivv4M6vz1pc=@vger.kernel.org X-Gm-Message-State: AOJu0YzLO/sLd1t5MuC9UW0A3FjUlAmw55ZEXwpVfQIDiFQmNRfT5iU8 olwSWKUY66yO2jMDsPgLwLeBr4Wyh/ctkPp7Ra54FOXw3sFMTqvFzEKD X-Gm-Gg: AfdE7cmuQwWPC56hk7NzOYmWouF/HaGfj6W9ydF0NQ/2W+wbjCV/d5Q1CPMcj7on6g0 nc1mcWuefiTrLFdHOw2AquBiMprCVnGfhG546WxUErjm7aLaTz7uaw3qOi25Uz4w0X4yrLfTFrw SAmOrV8DuR+Lcb3z88VosEwAtaB+Nl7d/HdjqxxYWfpsxOBeh+We7pPcqrHjl8GGfJiuKnIdras dJIbGn3c/QGD8nLowlqNduDTziEc+prNAdXKTiooNAre2SWu4aPAXK6vvPpVcdUc75Kduleh1xk YMgy4mRq4BUzNNvn5p/gD8UydPdloh766mQblmv0c6NgodpDNOXefVK4kwZ3mKjeGtM7jbvTjF/ 7rfHBmIWIKNG7BKqtLZ0HqniaQR5+wYAy52K4m2FXw2kZDdTLLBG/U7/XxgUiwO+Hoe3NQuWt7N 6CQVHLyWna5pQ8493WEjNjXPou40dpsf+6xFT5C4UNA8E8iPovvihuOf8+d5idsc4NaIv20jDB8 JTRnEIY7y0dmxUtg7ZU0fEqmGkSXC6Blfsl3kVe4jikoR64t3CHMmJE23eBAfR1KltfF/vYSumn X-Received: by 2002:a17:90b:2884:b0:387:e0db:bc22 with SMTP id 98e67ed59e1d1-38dc77b3846mr7049245a91.34.1783893642805; Sun, 12 Jul 2026 15:00:42 -0700 (PDT) Received: from ryzen.lan ([2601:644:8000:7a86::e35]) by smtp.gmail.com with ESMTPSA id 5a478bee46e88-313cb804197sm14856305eec.13.2026.07.12.15.00.41 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 12 Jul 2026 15:00:42 -0700 (PDT) From: Rosen Penev To: dmaengine@vger.kernel.org Cc: Andy Shevchenko , Vinod Koul , Frank Li , Kees Cook , "Gustavo A. R. Silva" , linux-kernel@vger.kernel.org (open list), linux-hardening@vger.kernel.org (open list:KERNEL HARDENING (not covered by other areas):Keyword:\b__counted_by(_le|_be|_ptr)?\b) Subject: [PATCHv2 1/2] dmaengine: idma64: use kzalloc_flex Date: Sun, 12 Jul 2026 15:00:38 -0700 Message-ID: <20260712220039.924958-2-rosenp@gmail.com> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260712220039.924958-1-rosenp@gmail.com> References: <20260712220039.924958-1-rosenp@gmail.com> Precedence: bulk X-Mailing-List: linux-hardening@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Simplifies allocations by using a flexible array member in this struct. Remove idma64_alloc_desc. It now offers no readability advantages in this single usage. Add __counted_by to get extra runtime analysis. Apply the exact same treatment to struct idma64_dma and devm_kzalloc. Signed-off-by: Rosen Penev Reviewed-by: Frank Li --- drivers/dma/idma64.c | 30 ++++-------------------------- drivers/dma/idma64.h | 4 ++-- 2 files changed, 6 insertions(+), 28 deletions(-) diff --git a/drivers/dma/idma64.c b/drivers/dma/idma64.c index 5fcd1befc92d..d914f50ec309 100644 --- a/drivers/dma/idma64.c +++ b/drivers/dma/idma64.c @@ -192,23 +192,6 @@ static irqreturn_t idma64_irq(int irq, void *dev) /* ---------------------------------------------------------------------- */ -static struct idma64_desc *idma64_alloc_desc(unsigned int ndesc) -{ - struct idma64_desc *desc; - - desc = kzalloc_obj(*desc, GFP_NOWAIT); - if (!desc) - return NULL; - - desc->hw = kzalloc_objs(*desc->hw, ndesc, GFP_NOWAIT); - if (!desc->hw) { - kfree(desc); - return NULL; - } - - return desc; -} - static void idma64_desc_free(struct idma64_chan *idma64c, struct idma64_desc *desc) { @@ -223,7 +206,6 @@ static void idma64_desc_free(struct idma64_chan *idma64c, } while (i); } - kfree(desc->hw); kfree(desc); } @@ -307,10 +289,12 @@ static struct dma_async_tx_descriptor *idma64_prep_slave_sg( struct scatterlist *sg; unsigned int i; - desc = idma64_alloc_desc(sg_len); + desc = kzalloc_flex(*desc, hw, sg_len, GFP_NOWAIT); if (!desc) return NULL; + desc->ndesc = sg_len; + for_each_sg(sgl, sg, sg_len, i) { struct idma64_hw_desc *hw = &desc->hw[i]; @@ -326,7 +310,6 @@ static struct dma_async_tx_descriptor *idma64_prep_slave_sg( hw->len = sg_dma_len(sg); } - desc->ndesc = sg_len; desc->direction = direction; desc->status = DMA_IN_PROGRESS; @@ -541,18 +524,13 @@ static int idma64_probe(struct idma64_chip *chip) unsigned short i; int ret; - idma64 = devm_kzalloc(chip->dev, sizeof(*idma64), GFP_KERNEL); + idma64 = devm_kzalloc(chip->dev, struct_size(idma64, chan, nr_chan), GFP_KERNEL); if (!idma64) return -ENOMEM; idma64->regs = chip->regs; chip->idma64 = idma64; - idma64->chan = devm_kcalloc(chip->dev, nr_chan, sizeof(*idma64->chan), - GFP_KERNEL); - if (!idma64->chan) - return -ENOMEM; - idma64->all_chan_mask = (1 << nr_chan) - 1; /* Turn off iDMA controller */ diff --git a/drivers/dma/idma64.h b/drivers/dma/idma64.h index d013b54356aa..1a67dbb24db5 100644 --- a/drivers/dma/idma64.h +++ b/drivers/dma/idma64.h @@ -113,10 +113,10 @@ struct idma64_hw_desc { struct idma64_desc { struct virt_dma_desc vdesc; enum dma_transfer_direction direction; - struct idma64_hw_desc *hw; unsigned int ndesc; size_t length; enum dma_status status; + struct idma64_hw_desc hw[] __counted_by(ndesc); }; static inline struct idma64_desc *to_idma64_desc(struct virt_dma_desc *vdesc) @@ -187,7 +187,7 @@ struct idma64 { /* channels */ unsigned short all_chan_mask; - struct idma64_chan *chan; + struct idma64_chan chan[]; }; static inline struct idma64 *to_idma64(struct dma_device *ddev) -- 2.55.0