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 9303F376A00; Wed, 10 Jun 2026 19:53:02 +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=1781121183; cv=none; b=hKiiZhjB8D4FEn+xffO2NXkReXanTBaQe02SvrZ1Hhl+v6e9vBLJichEoj9iFswtTZz9Ef+BytLiyJtxfPobvHZXh4IvJ7Cwx8OVwvn+HWOY3evt6qwq329tkEyp2bM8yPv+HkQ1rEF/RCzJnIZdI/6JqQwQX9cqeRqihSX2AlI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781121183; c=relaxed/simple; bh=6DHaEesU1HxcBe7IAQEFvPynqatqgSNZg56hKrmfej4=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=CuVyu/ePuyBpJztGBbNJbxCaZM15IMo4vdDpt59HYa1jpi/9yrx+ckFgUqtCmW7Q3afVLp+yRx2x2H8vsT9pr35R6KuwA47AGJtjxYjNxO2kk62pB2lKVU5qvCYp8ZbCg5MmC43IYKTtKzu4GazJUVlkPs7c369s6K80kfImHm4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=B5uGVixj; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="B5uGVixj" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B08EA1F00898; Wed, 10 Jun 2026 19:52:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1781121182; bh=1eyHbE/wfY3LRfOLgcFHF0JQRUUcUvxj8aZs9j1miaY=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=B5uGVixjX+YkK17ml0NvvzSl3VT3mLSpNWuXkW5LmJCbbY6oIgTZ+fTppAf7X29zp KhbijCJSQhrTXKDZcmb1dSGEei6OEQwMpis3x+94uwC5DVvcnFqZ5RXZvK7mEv5+ph OM/kkyII4yQ1Ks0IC8cwPgxHgC74uierLjwroUdZEWVRHyUv1MvR9br1qzL95wVQfm URRL+p9DJPZmQEjOKkD49kONLJV2xbjSpgip/NXVzUZdSMS1OIi5HrubaKZkjJY8lO gU2Nddfn0zQv71qanN0jiDvQj4vl+bsDkwaI2deVR6kYk+j910X5H/Ion6CM0rToD2 +GEe01/yHaSCw== From: Arnaldo Carvalho de Melo To: Namhyung Kim Cc: Ingo Molnar , Thomas Gleixner , James Clark , Jiri Olsa , Ian Rogers , Adrian Hunter , Clark Williams , linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, Arnaldo Carvalho de Melo , sashiko-bot , "Claude Opus 4.6" Subject: [PATCH 11/23] perf hwmon: Fix parse_hwmon_filename() strlcpy buffer overflow Date: Wed, 10 Jun 2026 16:51:44 -0300 Message-ID: <20260610195157.2091137-12-acme@kernel.org> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20260610195157.2091137-1-acme@kernel.org> References: <20260610195157.2091137-1-acme@kernel.org> Precedence: bulk X-Mailing-List: linux-perf-users@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Arnaldo Carvalho de Melo parse_hwmon_filename() strips the "_alarm" suffix from event names by copying into a 24-byte stack buffer: strlcpy(fn_type, fn_item, fn_item_len - 5); The third argument is the source length minus the suffix, not the destination buffer capacity. A long event name ending in "_alarm" can have fn_item_len - 5 > sizeof(fn_type), causing strlcpy() to write past the 24-byte fn_type[] array. The assert() only validates that the longest *valid* hwmon item fits, but does not protect against crafted input. Clamp the strlcpy size to min(fn_item_len - 5, sizeof(fn_type)). Fixes: 4810b761f812da3c ("perf hwmon_pmu: Add hwmon filename parser") Reported-by: sashiko-bot Cc: Ian Rogers Assisted-by: Claude Opus 4.6 Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/util/hwmon_pmu.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/tools/perf/util/hwmon_pmu.c b/tools/perf/util/hwmon_pmu.c index fbfb872ceb1826d8..bdcbe887579a1f08 100644 --- a/tools/perf/util/hwmon_pmu.c +++ b/tools/perf/util/hwmon_pmu.c @@ -202,7 +202,8 @@ bool parse_hwmon_filename(const char *filename, fn_item_len = strlen(fn_item); if (fn_item_len > 6 && !strcmp(&fn_item[fn_item_len - 6], "_alarm")) { assert(strlen(LONGEST_HWMON_ITEM_STR) < sizeof(fn_type)); - strlcpy(fn_type, fn_item, fn_item_len - 5); + /* fn_item_len - 5 strips "_alarm"; clamp to buffer size */ + strlcpy(fn_type, fn_item, min_t(size_t, fn_item_len - 5, sizeof(fn_type))); fn_item = fn_type; *alarm = true; } -- 2.54.0