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Biederman" , Florian Weimer , Christian Brauner , Dmitry Safonov <0x7f454c46@gmail.com>, linux-kernel@vger.kernel.org, linux-mm@kvack.org, Kees Cook Subject: Re: Potentially undesirable interactions between vfork() and time namespaces Message-ID: References: <87czcfhsme.fsf@email.froward.int.ebiederm.org> MIME-Version: 1.0 Content-Type: text/plain; charset=koi8-r Content-Disposition: inline In-Reply-To: ARC-Authentication-Results: i=1; imf06.hostedemail.com; dkim=pass header.d=gmail.com header.s=20210112 header.b=MfnMsa7b; spf=pass (imf06.hostedemail.com: domain of avagin@gmail.com designates 209.85.210.178 as permitted sender) smtp.mailfrom=avagin@gmail.com; dmarc=pass (policy=none) header.from=gmail.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1662139713; a=rsa-sha256; cv=none; b=fEs+JvFJfu3Q7H2hWNRsgTInqitLzWSFWbTQfOPsXUdIEzeMr9mtI76zSUIjIrmGLJjFbj StDndjnPa6be5/O/lbszE7WhcjihuEZ+ncxHgivyjfAcIfitPANKkgwnc/79awpfP53Tj5 hhSssdaiTxeIJp+E271z7StNlKmCjV4= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1662139713; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=KFNnGC2cvtFaF/K+nfKIMIDR7T43wT0YbieooabzRXA=; b=h/L93gecwpl+QKwTddbCOWfI0aWvHP4jvZZQQcrhgIVD0mIR9yJ1LDg0gN5K2DeY0AtlK4 dTANk9HYFYSuAY72MRx0v+zeb1K64DmLrcHK7tJCG+GKOowbGoFsf6BF/RnLIckDqAfZtx JcPINpYmGeP3CRuJrVFm++ExlWS0wuU= X-Rspamd-Queue-Id: F39BA180055 X-Rspam-User: Authentication-Results: imf06.hostedemail.com; dkim=pass header.d=gmail.com header.s=20210112 header.b=MfnMsa7b; spf=pass (imf06.hostedemail.com: domain of avagin@gmail.com designates 209.85.210.178 as permitted sender) smtp.mailfrom=avagin@gmail.com; dmarc=pass (policy=none) header.from=gmail.com X-Rspamd-Server: rspam09 X-Stat-Signature: uzs1bo79rig1sotowyyngdeqxu7k63hg X-HE-Tag: 1662139712-233134 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Fri, Sep 02, 2022 at 08:01:57PM +0300, Alexey Izbyshev wrote: > On 2022-09-01 21:11, Eric W. Biederman wrote: > > static int check_setns_flags(unsigned long flags) > > { > > if (!flags || (flags & ~(CLONE_NEWNS | CLONE_NEWUTS | CLONE_NEWIPC | > > > > > > > > To keep things from being too confusing it probably makes sense to > > rename the nsproxy variable from time_ns_for_children to > > time_ns_for_new_mm. Likewise timens_on_fork can be renamed > > timens_on_new_mm. > > > Do you imply renaming "/proc/[pid]/ns/time_for_children" as well, or will it > be preserved for compatibility? I don't think this is possible. It is used by a few tools already.