From patchwork Fri Dec 1 09:46:33 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yafang Shao X-Patchwork-Id: 13475575 X-Patchwork-Delegate: paul@paul-moore.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="KMkI7FMU" Received: from mail-pl1-x636.google.com (mail-pl1-x636.google.com [IPv6:2607:f8b0:4864:20::636]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D1FE910F3; Fri, 1 Dec 2023 01:47:11 -0800 (PST) Received: by mail-pl1-x636.google.com with SMTP id d9443c01a7336-1d04c097e34so2721845ad.0; Fri, 01 Dec 2023 01:47:11 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1701424031; x=1702028831; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=+x2gW85qXpDm39JWWNR8xOYWTSjKi1NE52O+Y4CVIzE=; b=KMkI7FMU9Atz0ySZLeHG7OtdPqYVZis4QBNf0frUQoGNdhT6sqbkwyH+I3xrPDBrVa HS1358VQ834+DAkw0itc5MoM377WJumHC6uz/ZVxOqXXj8xSnAQ17cL5F7n1aU9Tcdq4 qKJ8gVoaQaIdb2lEGWVwXyguZKANvWRyn9az2TGeY29yKTiN7WHYWFamkIGSzAMFki0B oWHOhFBB/njSUdLAFwLIveWR/XfGCQDTQ//PTBlW6aYsoKnQkzHdzM+C2rKcmjaaL8GT LE+vNg0LiN6eGDnYdrePZ2sabdRT7cDkDZmWf0KFwzT3dU5hEZf+2iw/mau7oCIWEKDe wYyg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1701424031; x=1702028831; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=+x2gW85qXpDm39JWWNR8xOYWTSjKi1NE52O+Y4CVIzE=; b=rgl6yFHal3ZhwgieBT8jPzUsLrmVzBCu9ljf37d4I4JPeQNoL4ETFL1/NLkvk/Jc3W fdhZZ9VM2CILg599Ra0PuhiPS5Fl2IdinSRIdgCFasitoRglBWWXRWfZ6zXGnV2Bb5Yn LTG9b8E25gxp3z9iB5+whdaWunKGiFxnBAirb2YpXrs5A98MUVfOh9gsd+QZ+lrkUrdw uInpUBxONjZmcBR2S4GZtWJcpxmBgwHTdpr//jOWqAACl+g8epCtFQ9hW9wlanRo4G50 GSzkPeetrrsbhW3vhH75wrNuIEcRUYbTdOc638WF+8NAAKaJ9HecDVc5RRcMfCtUq00g G4gA== X-Gm-Message-State: AOJu0YxwYsi8lx+xQViLVA2G2u3mC10dbEbhgE0SnM8NhwMRU6AlX1Sb IwaF4d6Ov23xaBogtdWqwh8= X-Google-Smtp-Source: AGHT+IEfi8CntkWgmrNALbbEki4QUlWGaiYFcUK8uZQCNPbFfdkSpNYq2ORQNXwcZZsO/tOOLRY9fA== X-Received: by 2002:a17:903:447:b0:1d0:5302:4642 with SMTP id iw7-20020a170903044700b001d053024642mr1803858plb.16.1701424031283; Fri, 01 Dec 2023 01:47:11 -0800 (PST) Received: from vultr.guest ([149.28.194.201]) by smtp.gmail.com with ESMTPSA id e6-20020a170902b78600b001bdd7579b5dsm2875534pls.240.2023.12.01.01.47.10 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 01 Dec 2023 01:47:10 -0800 (PST) From: Yafang Shao To: akpm@linux-foundation.org, paul@paul-moore.com, jmorris@namei.org, serge@hallyn.com, omosnace@redhat.com, mhocko@suse.com, ying.huang@intel.com Cc: linux-mm@kvack.org, linux-security-module@vger.kernel.org, bpf@vger.kernel.org, ligang.bdlg@bytedance.com, Yafang Shao Subject: [PATCH v3 4/7] mm, security: Add lsm hook for memory policy adjustment Date: Fri, 1 Dec 2023 09:46:33 +0000 Message-Id: <20231201094636.19770-5-laoar.shao@gmail.com> X-Mailer: git-send-email 2.39.3 In-Reply-To: <20231201094636.19770-1-laoar.shao@gmail.com> References: <20231201094636.19770-1-laoar.shao@gmail.com> Precedence: bulk X-Mailing-List: linux-security-module@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 In a containerized environment, independent memory binding by a user can lead to unexpected system issues or disrupt tasks being run by other users on the same server. If a user genuinely requires memory binding, we will allocate dedicated servers to them by leveraging kubelet deployment. At present, users have the capability to bind their memory to a specific node without explicit agreement or authorization from us. Consequently, a new LSM hook is introduced to mitigate this. This implementation allows us to exercise fine-grained control over memory policy adjustments within our container environment Signed-off-by: Yafang Shao --- include/linux/lsm_hook_defs.h | 3 +++ include/linux/security.h | 9 +++++++++ mm/mempolicy.c | 8 ++++++++ security/security.c | 13 +++++++++++++ 4 files changed, 33 insertions(+) diff --git a/include/linux/lsm_hook_defs.h b/include/linux/lsm_hook_defs.h index ff217a5ce552..558012719f98 100644 --- a/include/linux/lsm_hook_defs.h +++ b/include/linux/lsm_hook_defs.h @@ -419,3 +419,6 @@ LSM_HOOK(int, 0, uring_override_creds, const struct cred *new) LSM_HOOK(int, 0, uring_sqpoll, void) LSM_HOOK(int, 0, uring_cmd, struct io_uring_cmd *ioucmd) #endif /* CONFIG_IO_URING */ + +LSM_HOOK(int, 0, set_mempolicy, unsigned long mode, unsigned short mode_flags, + nodemask_t *nmask, unsigned int flags) diff --git a/include/linux/security.h b/include/linux/security.h index 1d1df326c881..cc4a19a0888c 100644 --- a/include/linux/security.h +++ b/include/linux/security.h @@ -484,6 +484,8 @@ int security_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen); int security_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen); int security_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen); int security_locked_down(enum lockdown_reason what); +int security_set_mempolicy(unsigned long mode, unsigned short mode_flags, + nodemask_t *nmask, unsigned int flags); #else /* CONFIG_SECURITY */ static inline int call_blocking_lsm_notifier(enum lsm_event event, void *data) @@ -1395,6 +1397,13 @@ static inline int security_locked_down(enum lockdown_reason what) { return 0; } + +static inline int +security_set_mempolicy(unsigned long mode, unsigned short mode_flags, + nodemask_t *nmask, unsigned int flags) +{ + return 0; +} #endif /* CONFIG_SECURITY */ #if defined(CONFIG_SECURITY) && defined(CONFIG_WATCH_QUEUE) diff --git a/mm/mempolicy.c b/mm/mempolicy.c index 1eafe81d782e..9a260dd24a4b 100644 --- a/mm/mempolicy.c +++ b/mm/mempolicy.c @@ -1495,6 +1495,10 @@ static long kernel_mbind(unsigned long start, unsigned long len, if (err) return err; + err = security_set_mempolicy(lmode, mode_flags, &nodes, flags); + if (err) + return err; + return do_mbind(start, len, lmode, mode_flags, &nodes, flags); } @@ -1589,6 +1593,10 @@ static long kernel_set_mempolicy(int mode, const unsigned long __user *nmask, if (err) return err; + err = security_set_mempolicy(lmode, mode_flags, &nodes, 0); + if (err) + return err; + return do_set_mempolicy(lmode, mode_flags, &nodes); } diff --git a/security/security.c b/security/security.c index dcb3e7014f9b..685ad7993753 100644 --- a/security/security.c +++ b/security/security.c @@ -5337,3 +5337,16 @@ int security_uring_cmd(struct io_uring_cmd *ioucmd) return call_int_hook(uring_cmd, 0, ioucmd); } #endif /* CONFIG_IO_URING */ + +/** + * security_set_mempolicy() - Check if memory policy can be adjusted + * @mode: The memory policy mode to be set + * @mode_flags: optional mode flags + * @nmask: modemask to which the mode applies + * @flags: mode flags for mbind(2) only + */ +int security_set_mempolicy(unsigned long mode, unsigned short mode_flags, + nodemask_t *nmask, unsigned int flags) +{ + return call_int_hook(set_mempolicy, 0, mode, mode_flags, nmask, flags); +}