From nobody Thu Apr 2 20:22:18 2026 Received: from forward102b.mail.yandex.net (forward102b.mail.yandex.net [178.154.239.149]) (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 063D035C1AD; Thu, 12 Feb 2026 12:56:41 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=178.154.239.149 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770901004; cv=none; b=uwOBmjEl0+/STPk7Xp7lK+Ni/eEPfGj7HrLj+I+07VN6dPULSB0AAWVGCgDeRBZHrrHYefllUMO6syjD7jeg613D0f2LZ3vvZI32bXD0linUSkk7UwqSTrKUZ9NScjeWK8VJmkWFJmWBOqG6OcrS7xOu6t7iVlsBZfCakHYmbp0= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770901004; c=relaxed/simple; bh=mnKuLEH8BfjkEMBC9cWgyEAo0Be6SXc3cyw+vkboY2w=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=j7UMkzr4BQ4xR6GM5CbSjJ27i1zusA/HUbQqavBds1pGyxheq+EQqXAdY4zXrf0IIA2afBe6iYrYOOuJk+c8DFdtqwE4+e070q0RalHbvqZyLrLfnG3JKwz/l5hSBtLwrn0NFxzGueQJK/QeJnmcEkaMuXmhuG8TNJtha3abAB0= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=yandex.ru; spf=pass smtp.mailfrom=yandex.ru; dkim=pass (1024-bit key) header.d=yandex.ru header.i=@yandex.ru header.b=Nqi6viXC; arc=none smtp.client-ip=178.154.239.149 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=yandex.ru Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=yandex.ru Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=yandex.ru header.i=@yandex.ru header.b="Nqi6viXC" Received: from mail-nwsmtp-smtp-production-main-70.sas.yp-c.yandex.net (mail-nwsmtp-smtp-production-main-70.sas.yp-c.yandex.net [IPv6:2a02:6b8:c11:e97:0:640:f294:0]) by forward102b.mail.yandex.net (Yandex) with ESMTPS id 2FFF2C0102; Thu, 12 Feb 2026 15:56:34 +0300 (MSK) Received: by mail-nwsmtp-smtp-production-main-70.sas.yp-c.yandex.net (smtp/Yandex) with ESMTPSA id VuTjuXAGI4Y0-yXnszrB9; Thu, 12 Feb 2026 15:56:33 +0300 X-Yandex-Fwd: 1 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=yandex.ru; s=mail; t=1770900993; bh=bUSYSYWj4dObYpG0McIjHrOKuumKhZrreSa3eiSsy1k=; h=Message-ID:Date:In-Reply-To:Cc:Subject:References:To:From; b=Nqi6viXC11Fa2rMq15n8chAksHUfXjGoSFL0T3C2NBu+Wpn0RzHmQAiFqikWz2ojm 8KkmqPXPY/1qOedErE5KL6rR9OT6YlyJwZULQq4zjSt/AiedNTRovSOE87KjXGkjhm +XsW9wlnoFeT9NJeyOaKyjRvIwiMUlBz+fim906g= Authentication-Results: mail-nwsmtp-smtp-production-main-70.sas.yp-c.yandex.net; dkim=pass header.i=@yandex.ru From: Dmitry Antipov To: Andy Shevchenko , Andrew Morton Cc: David Laight , Kees Cook , "Darrick J . Wong" , linux-hardening@vger.kernel.org, linux-kernel@vger.kernel.org, Dmitry Antipov Subject: [PATCH v7 2/5] lib: fix memparse() to handle overflow Date: Thu, 12 Feb 2026 15:56:25 +0300 Message-ID: <20260212125628.739276-3-dmantipov@yandex.ru> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260212125628.739276-1-dmantipov@yandex.ru> References: <20260212125628.739276-1-dmantipov@yandex.ru> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Since '_parse_integer_limit()' (and so 'simple_strtoull()') is now capable to handle overflow, adjust 'memparse()' to handle overflow (denoted by ULLONG_MAX) returned from 'simple_strtoull()'. Also use 'check_shl_overflow()' to catch an overflow possibly caused by processing size suffix and denote it with ULLONG_MAX as well. Signed-off-by: Dmitry Antipov Reviewed-by: Andy Shevchenko --- v7: do not double-adjust endptr and drop redundant check against ULLONG_MAX v6: handle valid-suffix-only string like "k" as unrecognized, minor style adjustments v5: initial version to join the series --- lib/cmdline.c | 27 +++++++++++++++++++-------- 1 file changed, 19 insertions(+), 8 deletions(-) diff --git a/lib/cmdline.c b/lib/cmdline.c index 90ed997d9570..32da6f5a9cdb 100644 --- a/lib/cmdline.c +++ b/lib/cmdline.c @@ -150,39 +150,50 @@ EXPORT_SYMBOL(get_options); unsigned long long memparse(const char *ptr, char **retptr) { char *endptr; /* local pointer to end of parsed string */ - unsigned long long ret =3D simple_strtoull(ptr, &endptr, 0); + unsigned int shl =3D 0; =20 + /* Consume valid suffix even in case of overflow. */ switch (*endptr) { case 'E': case 'e': - ret <<=3D 10; + shl +=3D 10; fallthrough; case 'P': case 'p': - ret <<=3D 10; + shl +=3D 10; fallthrough; case 'T': case 't': - ret <<=3D 10; + shl +=3D 10; fallthrough; case 'G': case 'g': - ret <<=3D 10; + shl +=3D 10; fallthrough; case 'M': case 'm': - ret <<=3D 10; + shl +=3D 10; fallthrough; case 'K': case 'k': - ret <<=3D 10; - endptr++; + shl +=3D 10; fallthrough; default: break; } =20 + if (shl && likely(ptr !=3D endptr)) { + /* Have valid suffix with preceding number. */ + unsigned long long val; + + if (unlikely(check_shl_overflow(ret, shl, &val))) + ret =3D ULLONG_MAX; + else + ret =3D val; + endptr++; + } + if (retptr) *retptr =3D endptr; =20 --=20 2.53.0