From nobody Mon Jul 27 23:14:56 2026 X-Original-To: dev-commits-src-main@mlmmj.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mlmmj.nyi.freebsd.org (Postfix) with ESMTP id 4h8Dvj2dtbz6m2Yf for ; Mon, 27 Jul 2026 23:14:57 +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 "YR1" (not verified)) by mx1.freebsd.org (Postfix) with ESMTPS id 4h8Dvj0Dv6z3MnR for ; Mon, 27 Jul 2026 23:14:57 +0000 (UTC) (envelope-from git@FreeBSD.org) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1785194097; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=ZSIIGkETRLZRlEIW3QFcRu/NLvSg7K+Dlyx9Yk0OOPI=; b=j3nWJJVah1OSNbdcunW4H1r3P3rCs8/HCglRjnhwAr8mBkdNpTiO1TeIJ42UzJNg8YwHUQ E5DJZRGaOCgTCygwusmeApuQc5B838UVz6HR0YyIpaqOqnpT6dlfURpExYJ746WTwJd5nU H5iIGAOpYhbhoyTXE2tXZxPUJEQU5on5XU7bjEFjpSXLJsvXhSEqqn6W9/2BOFstymdULA bUFGU1wpJ75FhVFyuCNUgX3Fhe9G7+GP4FH7wYhFJprTqyK67aTLJiZT7d7Mn/xkFdfcZE dqEliwpNZbSDoWLYDwypesviI6squzURoVE4x79T1mz0K85KvOPTJQdVkmsLSA== ARC-Seal: i=1; s=dkim; d=freebsd.org; t=1785194097; a=rsa-sha256; cv=none; b=GLaBiygf/FUKLFyqTaNLnY6dose3A7BnxlyuqK14hxinVJokq/p4NF0HvHaswZgndCgotf EBvojdTrVQl3BnHyzP8PwzVv9UmOIEoy6+0I3vptsJ5ggVvnM3KzJ3UIxSxT1ayAJEopKv cy2DTnJSu9G5d6PRNagzysh3oepaf7u5yW3oS0rvOz/L9jQ2jp0krbYPiMOdPDoBoFWf94 dDL6Jjmpy6pa7p3P2Hbd2PRxtTgQDqL75NRva0Cgxjd8r749M76CY0+OQ2s1grLbxuWIeJ qRbJG0RXQTHhrcsPldWSrDJg0HzSOJxDR+SgaUXqrbfx+GknFPtvemSiYR9pbg== ARC-Authentication-Results: i=1; mx1.freebsd.org; none ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1785194097; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=ZSIIGkETRLZRlEIW3QFcRu/NLvSg7K+Dlyx9Yk0OOPI=; b=ZxT9DGPIxcDtvklAyyeO2o8XbA75c39xhfrBWzq/d9O9kSdh2nh+8GRCKHBKQxOIp0wYwG bO+awHAe8e1sxbtQLy+DAkBnrNTMQUoTllXGr4YG5zKXJwzu63Boo7rk8sm0jvnTK0OOcg hgeu0HLyA0higoyh2y6UhbCU50PDQf+4f3fAwWRjP0qdcZYNV8pG1LU8Z0AiSZZUOTLPAX 5Lnlv7hlY6CxiA69o6Iw5tHk3IN8j28xHFEgqJYekDFD4z96M/QKLs5UEGCv2hBA02Uefw kW1yxiJSuZjM/Ihufe5eR4YJKCloJrX7/cdoZIkYj5KLAo5zP/hc71hY3HMPDA== Received: from gitrepo.freebsd.org (gitrepo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:5]) by mxrelay.nyi.freebsd.org (Postfix) with ESMTP id 4h8Dvh5tyLz1S0n for ; Mon, 27 Jul 2026 23:14:56 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from git (uid 1279) (envelope-from git@FreeBSD.org) id 306ef by gitrepo.freebsd.org (DragonFly Mail Agent v0.13+ on gitrepo.freebsd.org); Mon, 27 Jul 2026 23:14:56 +0000 To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-main@FreeBSD.org From: Mark Johnston Subject: git: 75be70064483 - main - umtx: Do not make an exiting thread the owner of a PI mutex List-Id: Commit messages for the main branch of the src repository List-Archive: https://lists.freebsd.org/archives/dev-commits-src-main List-Help: List-Post: List-Subscribe: List-Unsubscribe: X-BeenThere: dev-commits-src-main@freebsd.org Sender: owner-dev-commits-src-main@FreeBSD.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list 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: 75be70064483158da2b89ab412f83a4694560e58 Auto-Submitted: auto-generated Date: Mon, 27 Jul 2026 23:14:56 +0000 Message-Id: <6a67e670.306ef.5fc3393b@gitrepo.freebsd.org> The branch main has been updated by markj: URL: https://cgit.FreeBSD.org/src/commit/?id=75be70064483158da2b89ab412f83a4694560e58 commit 75be70064483158da2b89ab412f83a4694560e58 Author: Mark Johnston AuthorDate: 2026-07-27 23:12:37 +0000 Commit: Mark Johnston CommitDate: 2026-07-27 23:12:37 +0000 umtx: Do not make an exiting thread the owner of a PI mutex Otherwise an assertion in umtx_thread_alloc() (TAILQ_EMPTY(&uq->uq_pi_contested)) is violated. This use of TDB_EXIT is hacky, but I cannot see another way to check for an exiting thread without adding some more overhead to kern_thr_exit(). Fixes: 2a339d9e3dc1 Reported by: Maik Muench of Secfault Security Reviewed by: kib MFC after: 1 week Sponsored by: The FreeBSD Foundation Differential Revision: https://reviews.freebsd.org/D58447 --- sys/kern/kern_umtx.c | 21 +++++++++++++++------ 1 file changed, 15 insertions(+), 6 deletions(-) diff --git a/sys/kern/kern_umtx.c b/sys/kern/kern_umtx.c index ab6e578ab380..4f6e2b339ba6 100644 --- a/sys/kern/kern_umtx.c +++ b/sys/kern/kern_umtx.c @@ -2028,7 +2028,7 @@ int umtxq_sleep_pi(struct umtx_q *uq, struct umtx_pi *pi, uint32_t owner, const char *wmesg, struct umtx_abs_timeout *timo, bool shared) { - struct thread *td, *td1; + struct thread *td; struct umtx_q *uq1; int error, pri; #ifdef INVARIANTS @@ -2044,13 +2044,22 @@ umtxq_sleep_pi(struct umtx_q *uq, struct umtx_pi *pi, uint32_t owner, umtxq_insert(uq); mtx_lock(&umtx_lock); if (pi->pi_owner == NULL) { + struct thread *ownertd; + mtx_unlock(&umtx_lock); - td1 = tdfind(owner, shared ? -1 : td->td_proc->p_pid); + ownertd = tdfind(owner, shared ? -1 : td->td_proc->p_pid); mtx_lock(&umtx_lock); - if (td1 != NULL) { - if (pi->pi_owner == NULL) - umtx_pi_setowner(pi, td1); - PROC_UNLOCK(td1->td_proc); + if (ownertd != NULL) { + /* + * An exiting thread that has already called + * umtx_thread_exit() must not be made the owner of a + * shared mutex. + */ + if ((ownertd->td_proc->p_flag & P_WEXIT) == 0 && + (ownertd->td_dbgflags & TDB_EXIT) == 0 && + pi->pi_owner == NULL) + umtx_pi_setowner(pi, ownertd); + PROC_UNLOCK(ownertd->td_proc); } }