Date: Sat, 26 Apr 2003 18:04:47 -0700 (PDT) From: Linus Torvalds To: Roland McGrath cc: linux-kernel@vger.kernel.org Subject: Re: [PATCH] allow ptrace and /proc/PID/mem to read fixmap pages In-Reply-To: <200304262346.h3QNkL129881@magilla.sf.frob.com> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org X-Spam-Status: No, hits=-23.8 required=5.0 tests=AWL,EMAIL_ATTRIBUTION,IN_REP_TO,QUOTED_EMAIL_TEXT, REPLY_WITH_QUOTES,USER_AGENT_PINE,X_MAILING_LIST autolearn=ham version=2.53-osdl_revision__1.4__ X-Spam-Level: X-Spam-Checker-Version: SpamAssassin 2.53-osdl_revision__1.4__ (1.174.2.15-2003-03-30-exp) On Sat, 26 Apr 2003, Roland McGrath wrote: > > This patch is i386-specific and should probably be done another way, but > it's what I am using now. It works and is well-tested. It looks to me like it will cause NULL pointer dereferences if the user asks for something that is inside a pmd isn't mapped. Maybe that won't happen for the FIXADDR range, but this is just not acceptable. We don't do code without error handling in the kernel. Linus -