From owner-dev-commits-src-all@freebsd.org Sat Aug 28 19:55:26 2021 Return-Path: Delivered-To: dev-commits-src-all@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 699A46791A2; Sat, 28 Aug 2021 19:55:26 +0000 (UTC) (envelope-from git@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) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "mxrelay.nyi.freebsd.org", Issuer "R3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4GxnPV27Sbz4f6f; Sat, 28 Aug 2021 19:55:26 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from gitrepo.freebsd.org (gitrepo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:5]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id 2C46A1CE74; Sat, 28 Aug 2021 19:55:26 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from gitrepo.freebsd.org ([127.0.1.44]) by gitrepo.freebsd.org (8.16.1/8.16.1) with ESMTP id 17SJtQPq060405; Sat, 28 Aug 2021 19:55:26 GMT (envelope-from git@gitrepo.freebsd.org) Received: (from git@localhost) by gitrepo.freebsd.org (8.16.1/8.16.1/Submit) id 17SJtQTQ060404; Sat, 28 Aug 2021 19:55:26 GMT (envelope-from git) Date: Sat, 28 Aug 2021 19:55:26 GMT Message-Id: <202108281955.17SJtQTQ060404@gitrepo.freebsd.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-main@FreeBSD.org From: Mark Johnston Subject: git: 7326e8589cc2 - main - fsetown: Avoid process group lock recursion MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Git-Committer: markj X-Git-Repository: src X-Git-Refname: refs/heads/main X-Git-Reftype: branch X-Git-Commit: 7326e8589cc21431d62f25802eac7c5dd6f74122 Auto-Submitted: auto-generated X-BeenThere: dev-commits-src-all@freebsd.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: Commit messages for all branches of the src repository List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 28 Aug 2021 19:55:26 -0000 The branch main has been updated by markj: URL: https://cgit.FreeBSD.org/src/commit/?id=7326e8589cc21431d62f25802eac7c5dd6f74122 commit 7326e8589cc21431d62f25802eac7c5dd6f74122 Author: Mark Johnston AuthorDate: 2021-08-28 19:50:44 +0000 Commit: Mark Johnston CommitDate: 2021-08-28 19:50:44 +0000 fsetown: Avoid process group lock recursion Restore the pre-1d874ba4f8ba behaviour of disassociating the current SIGIO recipient before looking up the specified process or process group. This avoids a lock recursion in the scenario where a process group is configured to receive SIGIO for an fd when it has already been so configured. Reported by: pho Tested by: pho Reviewed by: kib MFC after: 3 days --- sys/kern/kern_descrip.c | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-) diff --git a/sys/kern/kern_descrip.c b/sys/kern/kern_descrip.c index f78e999ab3b5..ed7fe83cf02f 100644 --- a/sys/kern/kern_descrip.c +++ b/sys/kern/kern_descrip.c @@ -1158,14 +1158,12 @@ fsetown(pid_t pgid, struct sigio **sigiop) sigio->sio_ucred = crhold(curthread->td_ucred); sigio->sio_myref = sigiop; - osigio = NULL; ret = 0; if (pgid > 0) { ret = pget(pgid, PGET_NOTWEXIT | PGET_NOTID | PGET_HOLD, &proc); SIGIO_LOCK(); + osigio = funsetown_locked(*sigiop); if (ret == 0) { - osigio = funsetown_locked(*sigiop); - PROC_LOCK(proc); _PRELE(proc); if ((proc->p_flag & P_WEXIT) != 0) { @@ -1191,12 +1189,11 @@ fsetown(pid_t pgid, struct sigio **sigiop) } else /* if (pgid < 0) */ { sx_slock(&proctree_lock); SIGIO_LOCK(); + osigio = funsetown_locked(*sigiop); pgrp = pgfind(-pgid); if (pgrp == NULL) { ret = ESRCH; } else { - osigio = funsetown_locked(*sigiop); - if (pgrp->pg_session != curthread->td_proc->p_session) { /* * Policy - Don't allow a process to FSETOWN a