From owner-svn-src-head@freebsd.org Mon May 11 22:38:33 2020 Return-Path: Delivered-To: svn-src-head@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id 29C782D8C0A; Mon, 11 May 2020 22:38:33 +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 TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) server-signature RSA-PSS (4096 bits) client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "mxrelay.nyi.freebsd.org", Issuer "Let's Encrypt Authority X3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 49LbSS6t3lz4JyM; Mon, 11 May 2020 22:38:32 +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 C8E5925BFD; Mon, 11 May 2020 22:38:32 +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 04BMcWaT084431; Mon, 11 May 2020 22:38:32 GMT (envelope-from kib@FreeBSD.org) Received: (from kib@localhost) by repo.freebsd.org (8.15.2/8.15.2/Submit) id 04BMcWBV084430; Mon, 11 May 2020 22:38:32 GMT (envelope-from kib@FreeBSD.org) Message-Id: <202005112238.04BMcWBV084430@repo.freebsd.org> X-Authentication-Warning: repo.freebsd.org: kib set sender to kib@FreeBSD.org using -f From: Konstantin Belousov Date: Mon, 11 May 2020 22:38:32 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r360940 - head/sys/kern X-SVN-Group: head X-SVN-Commit-Author: kib X-SVN-Commit-Paths: head/sys/kern X-SVN-Commit-Revision: 360940 X-SVN-Commit-Repository: base MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-BeenThere: svn-src-head@freebsd.org X-Mailman-Version: 2.1.33 Precedence: list List-Id: SVN commit messages for the src tree for head/-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 11 May 2020 22:38:33 -0000 Author: kib Date: Mon May 11 22:38:32 2020 New Revision: 360940 URL: https://svnweb.freebsd.org/changeset/base/360940 Log: sigfastblock: fix delivery of the pending signals in single-threaded processes. If single-threaded process receives a signal during critical section established by sigfastblock(2) word, unblock did not caused signal delivery because sigfastblock(SIGFASTBLOCK_UNBLOCK) failed to request ast handling of the pending signals. Set TDF_ASTPENDING | TDF_NEEDSIGCHK on unblock or when kernel forces end of sigfastblock critical section, to cause syscall exit to recheck and deliver any signal pending. Reported by: corydoras@ridiculousfish.com PR: 246385 Sponsored by: The FreeBSD Foundation Modified: head/sys/kern/kern_sig.c Modified: head/sys/kern/kern_sig.c ============================================================================== --- head/sys/kern/kern_sig.c Mon May 11 22:26:39 2020 (r360939) +++ head/sys/kern/kern_sig.c Mon May 11 22:38:32 2020 (r360940) @@ -3976,6 +3976,22 @@ sigfastblock_fetch_sig(struct thread *td, bool sendsig return (true); } +static void +sigfastblock_resched(struct thread *td, bool resched) +{ + struct proc *p; + + if (resched) { + p = td->td_proc; + PROC_LOCK(p); + reschedule_signals(p, td->td_sigmask, 0); + PROC_UNLOCK(p); + } + thread_lock(td); + td->td_flags |= TDF_ASTPENDING | TDF_NEEDSIGCHK; + thread_unlock(td); +} + int sys_sigfastblock(struct thread *td, struct sigfastblock_args *uap) { @@ -4046,11 +4062,8 @@ sys_sigfastblock(struct thread *td, struct sigfastbloc * signals to current thread. But notify others about * fake unblock. */ - if (error == 0 && p->p_numthreads != 1) { - PROC_LOCK(p); - reschedule_signals(p, td->td_sigmask, 0); - PROC_UNLOCK(p); - } + sigfastblock_resched(td, error == 0 && p->p_numthreads != 1); + break; case SIGFASTBLOCK_UNSETPTR: @@ -4079,7 +4092,6 @@ sys_sigfastblock(struct thread *td, struct sigfastbloc void sigfastblock_clear(struct thread *td) { - struct proc *p; bool resched; if ((td->td_pflags & TDP_SIGFASTBLOCK) == 0) @@ -4088,12 +4100,7 @@ sigfastblock_clear(struct thread *td) resched = (td->td_pflags & TDP_SIGFASTPENDING) != 0 || SIGPENDING(td); td->td_pflags &= ~(TDP_SIGFASTBLOCK | TDP_SIGFASTPENDING); - if (resched) { - p = td->td_proc; - PROC_LOCK(p); - reschedule_signals(p, td->td_sigmask, 0); - PROC_UNLOCK(p); - } + sigfastblock_resched(td, resched); } void