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[71.184.117.43]) by smtp.gmail.com with ESMTPSA id n19sm16273215qkn.52.2020.01.03.04.48.48 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 03 Jan 2020 04:48:48 -0800 (PST) Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: quoted-printable From: Qian Cai Mime-Version: 1.0 (1.0) Subject: Re: [PATCH] slub: call BUG if next_object is not valid Date: Fri, 3 Jan 2020 07:48:47 -0500 Message-Id: <19578131-DF7A-486F-9198-B9294E04D450@lca.pw> References: Cc: Christoph Lameter , Pekka Enberg , David Rientjes , Joonsoo Kim , Andrew Morton , lijiazi , linux-mm@kvack.org In-Reply-To: To: lijiazi X-Mailer: iPhone Mail (17C54) X-Bogosity: Ham, tests=bogofilter, spamicity=0.000001, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: > On Jan 3, 2020, at 6:17 AM, lijiazi wrote: >=20 > If current object's memory is corrupted, there is a high > probability that next_objext stored in it will be rewritten as an > illegal value. It's better to check next_object this time than to > encounter a illegal pointer in next slub alloc like the following: Rather than papering over the issue, the key to figure out is how was the cu= rrent object memory corrupted?=