From nobody Wed Oct 1 23:27:54 2025 Received: from mail-lj1-f178.google.com (mail-lj1-f178.google.com [209.85.208.178]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 55B1321E091 for ; Thu, 25 Sep 2025 16:28:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.208.178 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1758817736; cv=none; b=GPkvPDP6vyAz72iYb+Lb71MTVID5SNJEOrLXRH6DjIXraGZot1oi+9CAWyvLVxXLXVeosvAr2XOsiEgORvAHETUUYpnkUsJE7BmZKVn08stfzYA44noc3TUpZvMh2P3/AtrearoJoQ3Q9Vpor87wq1bOsJq22hUq/mysGzuyv2A= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1758817736; c=relaxed/simple; bh=yVeHh1fU0YWUnblDCmkhki4+QgyK1imp/E2+6A4Pn4s=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=qY+5IYZ+qeD5NBd/LwydG+aQWs9BFXC8NmypPIwNaP9c3GjwodSrXa2ZIzF+so0dSl3Or2NLCU61rJyQOqDuFMrjF5ROE1Oj9TOQhiqGgtVk8VU+2GIIt9tyhp7EIHHPO4FENEjX+Q5L7IKBKuh4tkIDzSFvcJeb3bDhCqlVnj8= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=nrDpMXmO; arc=none smtp.client-ip=209.85.208.178 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="nrDpMXmO" Received: by mail-lj1-f178.google.com with SMTP id 38308e7fff4ca-368348d30e0so12202041fa.1 for ; Thu, 25 Sep 2025 09:28:55 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1758817733; x=1759422533; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc:subject:date:message-id:reply-to; bh=HnKoWYkEWH2fw2AAVRtHV79ItoxRJrbqLAVJ4MFNxIk=; b=nrDpMXmO7xA3w1Clr8JUDJiFyYr1fyhwu8EjeLJRnFuNHhliYTIH5LeKdLahi/JI8P yzeanFKkhPL3a+K7nJzIRVH3sJu56xdoiBYcPY/KVxL7H6088S5oYTZePVnF/vcagEoB /rroMFrxAOEn3lxVNbTWFsnh99VIm+M0Fbrd0v4V/J8ztR3YJgBKXVbd9BbNx08X8Q2r vwU8NyHttxsezGQnfgKTnMEXv5zIEiscC4M2hPjHL+IpY3STqJ7iCfJJ9/ORjk0esIqS mwOG6B/ovWTkZ8F5gPo1UiKQw3C7i6XQN6nLl06nsB9yMJP/RGAd3lupJrpwHU2o7jXu kY+g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1758817733; x=1759422533; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=HnKoWYkEWH2fw2AAVRtHV79ItoxRJrbqLAVJ4MFNxIk=; b=ciq/qYi0PfTJvKQdCKFZOlajbJcptSXmwLgpl7oOkoSJwcUTqhwVXEzejkiacA/Fzz xsWwfIS/LlHbsWgxtuCuLpiJ244wdmALnuSp4eWgzT8Omsauh1oeXBumGJpFNpY3wFsx 0vQmGB2cuOQIdSSOShm2D2IAkOjKf1UiEHr9AjvdW5nI8ZHd4gXRdsfjz9kUy+s67abA topDG1gC5FgiRVrQjTKBueLdmQHGmH62r01acRNhlURP4ZmklhPWsciojh9FGs8HvPqX f0Rz7/KvIwbbPDY65wW+RDAaV70n/5GqsA48ecxYggGFCRXaM0Lko9s0N6TWWTZOHYpb jF4w== X-Forwarded-Encrypted: i=1; AJvYcCXt3D0za/xmhyfWFhC7W82k60Bn4+Om6FUWtaDUVb4QMa1Me89qWRvrAMo3Qxxerdk9qn69KeFUg6l1ma4=@vger.kernel.org X-Gm-Message-State: AOJu0YyWKZ59AJX5JnwpVaq6M2chDYDG/HP6LkngESTXQf4tAIsgts5+ iniMcZpMAOfWDxd2VVxitDDOrkd/htEZwbyI5mb8rbr0mk8yuUnlGHu/ X-Gm-Gg: ASbGncshi9cQIlWcI54+zirWpxZCNaysM8q8wn6G9R98SLTuZyGWw363hF5IvCBnzos qLk6qPxTzVgemy8Ys2wkOt6h9jYBquWbuOasPy0DwkJNkVuhcxAUxWska1/GT5CTZAwd2ul7avN Va3ftegDgOfFllzhSaG202WT6eP2FkRSi4O3E4W/p8B0/VEGUABdIbhzUlWFBBGugLRVrafUECz MIZ1A92eOXt0nOKAvgwZQnU0/R/fzhjd++NLsovmmxAwrMpTPHhOmDymR++uF9ZGipjTEx0fN2G Hkwsl/9Pyh/n5EB3qHho9doXDvXK+JDHZBwIayzquECoELErt5VifGaV20fB23niEwHRDJes/67 4UHblzia2h99RzjGi0FAgkvNZp76MHwqclckI8AmVAz1UES4wEmAaLALlih7lxurYpAbMvi0aO1 9WBotigPO2+xjNuHQn X-Google-Smtp-Source: AGHT+IH0F4IcWkrWVCR3Qs2WUMHWwcPaxX4SRtmDCxFKqMOqVSiVXerIdiqRjKIypJnd8h3S0hrFDQ== X-Received: by 2002:a05:651c:154c:b0:36e:6146:673c with SMTP id 38308e7fff4ca-36f7dda4c6emr12606361fa.15.1758817733208; Thu, 25 Sep 2025 09:28:53 -0700 (PDT) Received: from localhost.localdomain (broadband-109-173-93-221.ip.moscow.rt.ru. [109.173.93.221]) by smtp.gmail.com with ESMTPSA id 38308e7fff4ca-36fb7fe7ba2sm6541231fa.64.2025.09.25.09.28.52 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 25 Sep 2025 09:28:52 -0700 (PDT) From: Alexandr Sapozhnkiov To: Neil Brown , Chuck Lever , Jeff Layton , Olga Kornievskaia , Dai Ngo , Tom Talpey , linux-nfs@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Alexandr Sapozhnikov , lvc-project@linuxtesting.org Subject: [PATCH] nfsd: fix arithmetic expression overflow in decode_saddr() Date: Thu, 25 Sep 2025 19:28:46 +0300 Message-ID: <20250925162848.11-1-alsp705@gmail.com> X-Mailer: git-send-email 2.43.0 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" From: Alexandr Sapozhnikov The value of an arithmetic expression tmp2 * NSEC_PER_USEC=20 is a subject to overflow because its operands are not cast=20 to a larger data type before performing arithmetic. If tmp2 =3D=3D 17,000,000 then the expression tmp2 * NSEC_PER_USEC will overflow because expression is of type u32. If tmp2 > 1,000,000 then tv_nsec will give be greater=20 than 1 second. Found by Linux Verification Center (linuxtesting.org) with SVACE. Signed-off-by: Alexandr Sapozhnikov --- fs/nfsd/nfsxdr.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/fs/nfsd/nfsxdr.c b/fs/nfsd/nfsxdr.c index 5777f40c7353..df62ed5099de 100644 --- a/fs/nfsd/nfsxdr.c +++ b/fs/nfsd/nfsxdr.c @@ -172,6 +172,8 @@ svcxdr_decode_sattr(struct svc_rqst *rqstp, struct xdr_= stream *xdr, tmp1 =3D be32_to_cpup(p++); tmp2 =3D be32_to_cpup(p++); if (tmp1 !=3D (u32)-1 && tmp2 !=3D (u32)-1) { + if (tmp2 > 999999) + tmp2 =3D 999999; iap->ia_valid |=3D ATTR_ATIME | ATTR_ATIME_SET; iap->ia_atime.tv_sec =3D tmp1; iap->ia_atime.tv_nsec =3D tmp2 * NSEC_PER_USEC; @@ -180,6 +182,8 @@ svcxdr_decode_sattr(struct svc_rqst *rqstp, struct xdr_= stream *xdr, tmp1 =3D be32_to_cpup(p++); tmp2 =3D be32_to_cpup(p++); if (tmp1 !=3D (u32)-1 && tmp2 !=3D (u32)-1) { + if (tmp2 > 1000000) + tmp2 =3D 999999; iap->ia_valid |=3D ATTR_MTIME | ATTR_MTIME_SET; iap->ia_mtime.tv_sec =3D tmp1; iap->ia_mtime.tv_nsec =3D tmp2 * NSEC_PER_USEC; --=20 2.43.0