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 82CE63EDAB8; Mon, 17 Aug 2026 13:40:20 +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=1786974022; cv=none; b=UWQFVfnTya8qouhtIQTt3+N9iZI6DdtNTyJnJvEdFsagqDOvInPNTi2eisF9FXawOe4q6ty1KdrpQc63PSfYwDxOboAF0r+E5eZn5Leb0QQsrIZndcmwlOqcgkaqsee0D5an9eux7wxCeOm4gm5Si9ikSHTjAjJOy0xYlu/MxNM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786974022; c=relaxed/simple; bh=PhXZlyzaWuZ373VjolGptz1V1t/Ghwect2Px/eciTqo=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=nrcHFLHr4aS6omxwWTn5fftbjbgMYS6mgfgPjjiI1vsbuneuz4oZuyLtV5yuTm/sH3lVRh5yhfKPe2B/oO3YTjTbCV/mlxKqPPL3/fv1DH7h+N5ZLMCtu2oA9lZnjmLLSAC3a4LLwU/WNWMGAkMFfaxe7A2vt33/7yoxN7FYsYg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=XMzj6n0p; 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="XMzj6n0p" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7D75F1F00A3A; Mon, 17 Aug 2026 13:40:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1786974020; bh=9GnYvIaZ5CdhG+Q/hexAfWN97+DN11LyIWHZJwuh3Mk=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=XMzj6n0pc73v99KewODVCqZXZoRJboQFtFOqFOrGiMXSveyhtHvmXFBgIxSg/vYhj /HUqCCVFxyA2vCSs9wc8zPgqItmgNopOOhkoorycN/WBw5WUyhoAfO8Yy3/gn8k8ch US7yuGOCRlNOCODpsGUqXx0KDXomZ3SpoB7cQx7U= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Babanpreet Singh , Joshua Crofts , William Breathitt Gray , Sasha Levin Subject: [PATCH 7.1 061/271] counter: microchip-tcb-capture: Fix DT channel validation Date: Mon, 17 Aug 2026 15:29:46 +0200 Message-ID: <20260817132539.255551955@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260817132536.752504388@linuxfoundation.org> References: <20260817132536.752504388@linuxfoundation.org> User-Agent: quilt/0.69 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 7.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Babanpreet Singh [ Upstream commit f1a3a9946aab611dd2200c01ff122f64b033dad2 ] mchp_tc_probe() reads the devicetree "reg" cell - a u32, per the API contract of of_property_read_u32_index() - into a signed int, so the bounds check "channel > 2" fails to reject cell values at or above 0x80000000: reinterpreted as a negative int, they compare below 2 and pass validation. A malformed devicetree can therefore drive a negative channel into the ATMEL_TC_REG() offset arithmetic, making the driver access syscon regmap offsets outside the TC block's register window, and into the "t%d_clk" clock-name formatting, where it truncates clk_name (sized for "t0_clk".."t2_clk"). Declare channel as u32, matching the API contract; the unsigned comparison then rejects everything except channels 0..2. Adjust the format specifier to %u accordingly, which also resolves the W=1 warning that exposed the gap: microchip-tcb-capture.c:520:56: warning: '%d' directive output may be truncated writing between 1 and 11 bytes into a region of size 6 [-Wformat-truncation=] note: directive argument in the range [-2147483648, 2] No behavior change for well-formed devicetrees: channels 0..2 take identical paths before and after. Fixes: 106b104137fd ("counter: Add microchip TCB capture counter") Assisted-by: Claude:claude-fable-5 [gcc W=1] Signed-off-by: Babanpreet Singh Reviewed-by: Joshua Crofts Link: https://lore.kernel.org/r/20260714042910.7-1-bbnpreetsingh@gmail.com Signed-off-by: William Breathitt Gray Signed-off-by: Sasha Levin --- drivers/counter/microchip-tcb-capture.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/counter/microchip-tcb-capture.c b/drivers/counter/microchip-tcb-capture.c index 19d457ae4c3bb..e53a8390756b7 100644 --- a/drivers/counter/microchip-tcb-capture.c +++ b/drivers/counter/microchip-tcb-capture.c @@ -483,7 +483,7 @@ static int mchp_tc_probe(struct platform_device *pdev) char clk_name[7]; struct regmap *regmap; struct clk *clk[3]; - int channel; + u32 channel; int ret, i; counter = devm_counter_alloc(&pdev->dev, sizeof(*priv)); @@ -517,7 +517,7 @@ static int mchp_tc_probe(struct platform_device *pdev) priv->channel[i] = channel; - snprintf(clk_name, sizeof(clk_name), "t%d_clk", channel); + snprintf(clk_name, sizeof(clk_name), "t%u_clk", channel); clk[i] = of_clk_get_by_name(np->parent, clk_name); if (IS_ERR(clk[i])) { -- 2.53.0