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[209.132.180.67]) by mx.google.com with ESMTP id q8-v6si2494805pgf.293.2018.05.11.04.29.02; Fri, 11 May 2018 04:29:17 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; dkim=pass header.i=@gmail.com header.s=20161025 header.b=Zfp00NHj; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=QUARANTINE dis=NONE) header.from=gmail.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752857AbeEKL1Y (ORCPT + 99 others); Fri, 11 May 2018 07:27:24 -0400 Received: from mail-pg0-f68.google.com ([74.125.83.68]:39149 "EHLO mail-pg0-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752394AbeEKL1W (ORCPT ); Fri, 11 May 2018 07:27:22 -0400 Received: by mail-pg0-f68.google.com with SMTP id e1-v6so2323839pga.6 for ; Fri, 11 May 2018 04:27:22 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=OUlEL0M7hcpsTac2UaxxrGerde/seQ7VORYb75gg0qA=; b=Zfp00NHjb/gw8i7aeeK6eYBHaKEqc5m2N0x44t2444UxRJsBEeSWtf/HuIloUiwo0C j9uGF+ZjRIv/8G9Y+kKx6+qUGt1LrizIocpC+AuV8RzNfnIBq6sY2Aqh7apIK5qRSeXG Uji7Zea8Kt/ksLbfEZZDnc3ZWj9ji8qoaeTLbSloR+d8aRTrQSnAs27Xo4wkgJ4SIFNF jvSfGHde44RoObY6ImO6KNEl6//1KebDqSx6gbQDUIS6Js7Bj4cBJfOkKV2/yNfD7h+m 2HlbTTvsEjSn0K/+Y77riJl6naNUd1G+I2ZaI7C+GZyL5Iwi2MfIYVm7zY3PPN9pY8FG rXCQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=OUlEL0M7hcpsTac2UaxxrGerde/seQ7VORYb75gg0qA=; b=Co06V6tiozWLl5GPdW4rHrGKM4ZE5eN/NVlqR3PYy72k0pLMgaReAdW5mJFJLKU8Zg TPLP0l7ordL3ad1Jg+Fd6synLvXXAgesnDHJID9+e1ersuMn9OgXotTuXlO9VrApWqne hgCO54ZfSVlhuy7PawL4JK3Bh6uJh1wx23INgrjAIr6VBdnHblcGg3LmY7DEBwvBLArz kmnkyp2faoH7q8JD9X6HbfZjWbvGz3BIsi8LBtU3aTLHe02OZiLaDIIjoP6JOFQoU67y J6xW8NPWNk5nIlXkjtCYBEqxJ65qyFjGBogyhXCt/ATo2D+t4bR2CIlh2FXIfa841Uyd ukew== X-Gm-Message-State: ALKqPwcrQIHQ4WQOz+1T4LqqG/N3TYbKxk6NeKsI0CmPFvuMxCLzAKGf U91PDuuOdyz00/DVwGyxKxs= X-Received: by 2002:a63:6703:: with SMTP id b3-v6mr4062798pgc.176.1526038042504; Fri, 11 May 2018 04:27:22 -0700 (PDT) Received: from localhost ([211.246.69.73]) by smtp.gmail.com with ESMTPSA id t14-v6sm8004662pfh.109.2018.05.11.04.27.20 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Fri, 11 May 2018 04:27:21 -0700 (PDT) Date: Fri, 11 May 2018 20:27:18 +0900 From: Sergey Senozhatsky To: Tetsuo Handa Cc: sergey.senozhatsky.work@gmail.com, pmladek@suse.com, dvyukov@google.com, sergey.senozhatsky@gmail.com, syzkaller@googlegroups.com, rostedt@goodmis.org, fengguang.wu@intel.com, linux-kernel@vger.kernel.org, peterz@infradead.org Subject: Re: [PATCH] printk: fix possible reuse of va_list variable Message-ID: <20180511112718.GA17477@jagdpanzerIV> References: <201805102350.JJH73950.tVJHQLFSOMOOFF@I-love.SAKURA.ne.jp> <20180511014515.GA895@jagdpanzerIV> <201805110238.w4B2cIGH079602@www262.sakura.ne.jp> <20180511062151.GA18160@jagdpanzerIV> <201805112002.GIF21216.OFVHFOMLJtQFSO@I-love.SAKURA.ne.jp> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <201805112002.GIF21216.OFVHFOMLJtQFSO@I-love.SAKURA.ne.jp> User-Agent: Mutt/1.9.5 (2018-04-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On (05/11/18 20:02), Tetsuo Handa wrote: > I noticed that there is a possibility that printk_safe_log_store() causes > kernel oops because "args" parameter is passed to vsnprintf() again when > atomic_cmpxchg() detected that we raced. Fix this by using va_copy(). > > Signed-off-by: Tetsuo Handa > Fixes: 42a0bb3f71383b45 ("printk/nmi: generic solution for safe printk in NMI") > Cc: Sergey Senozhatsky > Cc: Petr Mladek > Cc: Peter Zijlstra > Cc: Steven Rostedt Reviewed-by: Sergey Senozhatsky -ss