From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 E03A8101D4; Mon, 18 Dec 2023 13:58:12 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="igi7kQL/" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1758BC433C7; Mon, 18 Dec 2023 13:58:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1702907892; bh=rv0f392ADzGv4+tHISvNcSBxPP5h2yuT96wOaZiQbOs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=igi7kQL/jdv0zTfvGiJ1uaGrePdFNJKF75kKYxtEYItrfT9vK1Hhinyf3M20LtQj2 pwPbEaxnEKqa/+3iPII7IK1BVpcqR5bz7Xnz22JGvs+k6JRd7DPCwH3xLKKm2LbTuv qveu4bWPKeECGVIP7uMPuNmjcnDb4A2/r6ppjfZc= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Arnd Bergmann , Amelie Delaunay , kernel test robot , Vinod Koul Subject: [PATCH 6.1 084/106] dmaengine: stm32-dma: avoid bitfield overflow assertion Date: Mon, 18 Dec 2023 14:51:38 +0100 Message-ID: <20231218135058.662094090@linuxfoundation.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20231218135055.005497074@linuxfoundation.org> References: <20231218135055.005497074@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Amelie Delaunay commit 54bed6bafa0f38daf9697af50e3aff5ff1354fe1 upstream. stm32_dma_get_burst() returns a negative error for invalid input, which gets turned into a large u32 value in stm32_dma_prep_dma_memcpy() that in turn triggers an assertion because it does not fit into a two-bit field: drivers/dma/stm32-dma.c: In function 'stm32_dma_prep_dma_memcpy': include/linux/compiler_types.h:354:38: error: call to '__compiletime_assert_282' declared with attribute error: FIELD_PREP: value too large for the field _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__) ^ include/linux/compiler_types.h:335:4: note: in definition of macro '__compiletime_assert' prefix ## suffix(); \ ^~~~~~ include/linux/compiler_types.h:354:2: note: in expansion of macro '_compiletime_assert' _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__) ^~~~~~~~~~~~~~~~~~~ include/linux/build_bug.h:39:37: note: in expansion of macro 'compiletime_assert' #define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg) ^~~~~~~~~~~~~~~~~~ include/linux/bitfield.h:68:3: note: in expansion of macro 'BUILD_BUG_ON_MSG' BUILD_BUG_ON_MSG(__builtin_constant_p(_val) ? \ ^~~~~~~~~~~~~~~~ include/linux/bitfield.h:114:3: note: in expansion of macro '__BF_FIELD_CHECK' __BF_FIELD_CHECK(_mask, 0ULL, _val, "FIELD_PREP: "); \ ^~~~~~~~~~~~~~~~ drivers/dma/stm32-dma.c:1237:4: note: in expansion of macro 'FIELD_PREP' FIELD_PREP(STM32_DMA_SCR_PBURST_MASK, dma_burst) | ^~~~~~~~~~ As an easy workaround, assume the error can happen, so try to handle this by failing stm32_dma_prep_dma_memcpy() before the assertion. It replicates what is done in stm32_dma_set_xfer_param() where stm32_dma_get_burst() is also used. Fixes: 1c32d6c37cc2 ("dmaengine: stm32-dma: use bitfield helpers") Fixes: a2b6103b7a8a ("dmaengine: stm32-dma: Improve memory burst management") Signed-off-by: Arnd Bergmann Signed-off-by: Amelie Delaunay Cc: stable@vger.kernel.org Reported-by: kernel test robot Closes: https://lore.kernel.org/oe-kbuild-all/202311060135.Q9eMnpCL-lkp@intel.com/ Link: https://lore.kernel.org/r/20231106134832.1470305-1-amelie.delaunay@foss.st.com Signed-off-by: Vinod Koul Signed-off-by: Greg Kroah-Hartman --- drivers/dma/stm32-dma.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) --- a/drivers/dma/stm32-dma.c +++ b/drivers/dma/stm32-dma.c @@ -1249,8 +1249,8 @@ static struct dma_async_tx_descriptor *s enum dma_slave_buswidth max_width; struct stm32_dma_desc *desc; size_t xfer_count, offset; - u32 num_sgs, best_burst, dma_burst, threshold; - int i; + u32 num_sgs, best_burst, threshold; + int dma_burst, i; num_sgs = DIV_ROUND_UP(len, STM32_DMA_ALIGNED_MAX_DATA_ITEMS); desc = kzalloc(struct_size(desc, sg_req, num_sgs), GFP_NOWAIT); @@ -1268,6 +1268,10 @@ static struct dma_async_tx_descriptor *s best_burst = stm32_dma_get_best_burst(len, STM32_DMA_MAX_BURST, threshold, max_width); dma_burst = stm32_dma_get_burst(chan, best_burst); + if (dma_burst < 0) { + kfree(desc); + return NULL; + } stm32_dma_clear_reg(&desc->sg_req[i].chan_reg); desc->sg_req[i].chan_reg.dma_scr =