From owner-svn-src-all@freebsd.org Tue Nov 27 19:50:59 2018 Return-Path: Delivered-To: svn-src-all@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 063CB1159F56; Tue, 27 Nov 2018 19:50:59 +0000 (UTC) (envelope-from kib@FreeBSD.org) Received: from mxrelay.nyi.freebsd.org (mxrelay.nyi.freebsd.org [IPv6:2610:1c1:1:606c::19:3]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "mxrelay.nyi.freebsd.org", Issuer "Let's Encrypt Authority X3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id A174E69F37; Tue, 27 Nov 2018 19:50:58 +0000 (UTC) (envelope-from kib@FreeBSD.org) Received: from repo.freebsd.org (repo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:0]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id 828C11FFB5; Tue, 27 Nov 2018 19:50:58 +0000 (UTC) (envelope-from kib@FreeBSD.org) Received: from repo.freebsd.org ([127.0.1.37]) by repo.freebsd.org (8.15.2/8.15.2) with ESMTP id wARJowJA041215; Tue, 27 Nov 2018 19:50:58 GMT (envelope-from kib@FreeBSD.org) Received: (from kib@localhost) by repo.freebsd.org (8.15.2/8.15.2/Submit) id wARJowtQ041214; Tue, 27 Nov 2018 19:50:58 GMT (envelope-from kib@FreeBSD.org) Message-Id: <201811271950.wARJowtQ041214@repo.freebsd.org> X-Authentication-Warning: repo.freebsd.org: kib set sender to kib@FreeBSD.org using -f From: Konstantin Belousov Date: Tue, 27 Nov 2018 19:50:58 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r341094 - head/sys/kern X-SVN-Group: head X-SVN-Commit-Author: kib X-SVN-Commit-Paths: head/sys/kern X-SVN-Commit-Revision: 341094 X-SVN-Commit-Repository: base MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Rspamd-Queue-Id: A174E69F37 X-Spamd-Result: default: False [1.32 / 15.00]; local_wl_from(0.00)[FreeBSD.org]; NEURAL_SPAM_LONG(0.47)[0.465,0]; NEURAL_SPAM_MEDIUM(0.64)[0.643,0]; ASN(0.00)[asn:11403, ipnet:2610:1c1:1::/48, country:US]; NEURAL_SPAM_SHORT(0.21)[0.213,0] X-Rspamd-Server: mx1.freebsd.org X-BeenThere: svn-src-all@freebsd.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: "SVN commit messages for the entire src tree \(except for " user" and " projects" \)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 27 Nov 2018 19:50:59 -0000 Author: kib Date: Tue Nov 27 19:50:58 2018 New Revision: 341094 URL: https://svnweb.freebsd.org/changeset/base/341094 Log: Improve sigonstack(). Avoid relying on unsigned overflow for the test. Simplify expressions to avoid duplicate check for the range. Style. Add herald comment. Reviewed by: jhb Sponsored by: The FreeBSD Foundation MFC after: 1 week Differential revision: https://reviews.freebsd.org/D18361 Modified: head/sys/kern/kern_sig.c Modified: head/sys/kern/kern_sig.c ============================================================================== --- head/sys/kern/kern_sig.c Tue Nov 27 19:45:25 2018 (r341093) +++ head/sys/kern/kern_sig.c Tue Nov 27 19:50:58 2018 (r341094) @@ -615,20 +615,25 @@ signotify(struct thread *td) } } +/* + * Returns 1 (true) if altstack is configured for the thread, and the + * passed stack bottom address falls into the altstack range. Handles + * the 43 compat special case where the alt stack size is zero. + */ int sigonstack(size_t sp) { - struct thread *td = curthread; + struct thread *td; - return ((td->td_pflags & TDP_ALTSTACK) ? + td = curthread; + if ((td->td_pflags & TDP_ALTSTACK) == 0) + return (0); #if defined(COMPAT_43) - ((td->td_sigstk.ss_size == 0) ? - (td->td_sigstk.ss_flags & SS_ONSTACK) : - ((sp - (size_t)td->td_sigstk.ss_sp) < td->td_sigstk.ss_size)) -#else - ((sp - (size_t)td->td_sigstk.ss_sp) < td->td_sigstk.ss_size) + if (td->td_sigstk.ss_size == 0) + return ((td->td_sigstk.ss_flags & SS_ONSTACK) != 0); #endif - : 0); + return (sp >= (size_t)td->td_sigstk.ss_sp && + sp < td->td_sigstk.ss_size + (size_t)td->td_sigstk.ss_sp); } static __inline int