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 9A64225DCFA; Tue, 11 Mar 2025 15:29:24 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741706964; cv=none; b=KhvAPSn80of3GBTHltYmc/qAdz2JhFuLh7XdVVmD+CQVAbiVOnBmTky7JkpaKbnwdkOPkvYGWFTrO7dMU8+NnmPrHIge7r/fkNlxT9xm6TdFsUPRHC84Q6lPMPjWQUxUEWZrTQDeqLLcsT2/8rRqQswjTkx3fP5jD2rtrsbbPhI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741706964; c=relaxed/simple; bh=lAmmVv3XdMEtAcqCkvN/o2/MFSTDUnSIb8abyR2vz1E=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=buusgM+KiLImqGurKuKFVGiaIvIXH4soHMl0j4zAf6BkqnIc1Jo6JjI23CHrGPhg/aV8gdG0ytSBMhLZkCHcdxnYx/Ltjb8CFSx/A917ZY65ml0N+kEh3ltQKdcW5y1C4rklo7RQwyTjzSlWseg70QXosg8bXlMws4NLt7iMEd8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=z0ucV9Xw; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="z0ucV9Xw" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 220D1C4CEE9; Tue, 11 Mar 2025 15:29:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1741706964; bh=lAmmVv3XdMEtAcqCkvN/o2/MFSTDUnSIb8abyR2vz1E=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=z0ucV9XwD+8Q/FyOYTfUKauU4ij+pGA5CayVmKK+pxi3WI6WpdhdFb3jMp5jorTY0 fwXVQQKocaiaWFQvsdSWWJkHC0g0y06rTMSTIIxHk2yc0EGnE0+G/tDXCZ3L7oYSkj lUM0n9PS953AILTqFyFrJMLRlSH15Nlu9T+g68kU= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Jennifer Berringer , Srinivas Kandagatla Subject: [PATCH 5.10 211/462] nvmem: core: improve range check for nvmem_cell_write() Date: Tue, 11 Mar 2025 15:57:57 +0100 Message-ID: <20250311145806.698257779@linuxfoundation.org> X-Mailer: git-send-email 2.48.1 In-Reply-To: <20250311145758.343076290@linuxfoundation.org> References: <20250311145758.343076290@linuxfoundation.org> User-Agent: quilt/0.68 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 5.10-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jennifer Berringer commit 31507fc2ad36e0071751a710449db19c85d82a7f upstream. When __nvmem_cell_entry_write() is called for an nvmem cell that does not need bit shifting, it requires that the len parameter exactly matches the nvmem cell size. However, when the nvmem cell has a nonzero bit_offset, it was skipping this check. Accepting values of len larger than the cell size results in nvmem_cell_prepare_write_buffer() trying to write past the end of a heap buffer that it allocates. Add a check to avoid that problem and instead return -EINVAL when len doesn't match the number of bits expected by the nvmem cell when bit_offset is nonzero. This check uses cell->nbits in order to allow providing the smaller size to cells that are shifted into another byte by bit_offset. For example, a cell with nbits=8 and nonzero bit_offset would have bytes=2 but should accept a 1-byte write here, although no current callers depend on this. Fixes: 69aba7948cbe ("nvmem: Add a simple NVMEM framework for consumers") Cc: stable@vger.kernel.org Signed-off-by: Jennifer Berringer Signed-off-by: Srinivas Kandagatla Link: https://lore.kernel.org/r/20241230141901.263976-7-srinivas.kandagatla@linaro.org Signed-off-by: Greg Kroah-Hartman Signed-off-by: Greg Kroah-Hartman --- drivers/nvmem/core.c | 2 ++ 1 file changed, 2 insertions(+) --- a/drivers/nvmem/core.c +++ b/drivers/nvmem/core.c @@ -1362,6 +1362,8 @@ int nvmem_cell_write(struct nvmem_cell * return -EINVAL; if (cell->bit_offset || cell->nbits) { + if (len != BITS_TO_BYTES(cell->nbits) && len != cell->bytes) + return -EINVAL; buf = nvmem_cell_prepare_write_buffer(cell, buf, len); if (IS_ERR(buf)) return PTR_ERR(buf);