From nobody Mon Aug 24 16:30:03 2026 X-Original-To: dev-commits-src-all@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 4hTGbb58Vpz6pbSF for ; Mon, 24 Aug 2026 16:30:03 +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 "YR2" (not verified)) by mx1.freebsd.org (Postfix) with ESMTPS id 4hTGbb2hZLz41Xh for ; Mon, 24 Aug 2026 16:30:03 +0000 (UTC) (envelope-from git@FreeBSD.org) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1787589003; 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=xVO0yASGypHUhl2TFK1lBTygPaokYE1EDZvvfEZB7uU=; b=ghJlgOuoUpPSZR9fZ7+LppgDIPRtmquAasB3NtZ/CiZ6yRDTlQIEu7Rps7QC1+HX3ZpBi0 2al+l4HYPe8UjHKyE1lbGJUA8HV40OqvM+fpMLmLjXurZB6rMl6x9sq0Ed8kwSaoTPKHbI DQ1OAIbI5qk0IxqgGIvWkKokBfeBPANrUgg2oYRBcQe+2NS4SVbUYk20o5zwRL9idb23qX B0HtXBsM4cM7gWXYpSdkMLABpcv+9GvSGu6of1ZgGLGNowAx8aQpPV65yPf1EIsPMcXH8O UXOIjcG+GrRQ8/dvAAQbj8WS80YUOhoGf5Nxn2vF11BHu2N5FlsuHBXfY8GW4w== ARC-Seal: i=1; s=dkim; d=freebsd.org; t=1787589003; a=rsa-sha256; cv=none; b=j17VFkJFVQmtgTnptIaxL6Zy17K2aMoe28ICKsMbQMjqUjrn42oX6PhOReK4B6gb0B/QD3 Z99ycIsvyLStPthBObZ5IS+2Nvi0lBNXvSplHuMimw356ArXmIwB1Lt3WIGLGCZ8wLLhjJ b+HfEU1cS/LFyLi/+3dWH4ZhlgzkikOC1HDZLYJhGtJ7wsAYANxik+rPOLufP1hzaxytpu CXDm8gUL9ailMu2FjLFbK4gL2K8axcjD+ESlGq82MNW9o85scF9O3PJstg//oG2UD1ixT5 W2ZjJgGgHnc7QR/Oef84KZP5v74rDgZWZjuFKCFOg+edU8kY3WZnF7yh6tJ0FA== 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=1787589003; 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=xVO0yASGypHUhl2TFK1lBTygPaokYE1EDZvvfEZB7uU=; b=GqdZSZ6EZk5f5gl46/s0KZ8AoXxEOcK1IgqzW/JFjNLMdmxWEaUweLIVwkCSXxy62nEVbi gxtbu1Hvs3Q4XPi1ehIQfaqC3J+zglQ1WQrL+IbyORZn/2SQ8qPrlCqrwJz9bq4csh9KxQ yXjDr4+PfFutzi5EjWtwRYv88WSyKrkRjW2rZH5M9ErilQOoIIBftrIWW68HJMi0t05ZQD Ab4dvRjuoTvHBbas1Maik31sKJ8x9wQ1X9qWdeUfs4xHUr22kJlf/Rw0JxCFXBm//PzuQa zhYBMIw3sM9oPRn24mMxP90nyoqdzIf8QLcorzdjUXC6gzoARgGgbUmLPwR0zw== Received: from gitrepo.freebsd.org (gitrepo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:5]) by mxrelay.nyi.freebsd.org (Postfix) with ESMTP id 4hTGbb1Y2Nz19rR for ; Mon, 24 Aug 2026 16:30:03 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from git (uid 1279) (envelope-from git@FreeBSD.org) id 22257 by gitrepo.freebsd.org (DragonFly Mail Agent v0.13+ on gitrepo.freebsd.org); Mon, 24 Aug 2026 16:30:03 +0000 To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-branches@FreeBSD.org From: Mark Johnston Subject: git: 6edbfb48fc1a - stable/15 - uma: Enqueue full buckets in FIFO order when KASAN is configured List-Id: Commit messages for all branches of the src repository List-Archive: https://lists.freebsd.org/archives/dev-commits-src-all List-Help: List-Post: List-Subscribe: List-Unsubscribe: X-BeenThere: dev-commits-src-all@freebsd.org Sender: owner-dev-commits-src-all@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/stable/15 X-Git-Reftype: branch X-Git-Commit: 6edbfb48fc1ac02ef12b3ae9e0955ff317c286a3 Auto-Submitted: auto-generated Date: Mon, 24 Aug 2026 16:30:03 +0000 Message-Id: <6a8c718b.22257.5ea21e20@gitrepo.freebsd.org> The branch stable/15 has been updated by markj: URL: https://cgit.FreeBSD.org/src/commit/?id=6edbfb48fc1ac02ef12b3ae9e0955ff317c286a3 commit 6edbfb48fc1ac02ef12b3ae9e0955ff317c286a3 Author: Mark Johnston AuthorDate: 2026-07-24 21:12:33 +0000 Commit: Mark Johnston CommitDate: 2026-08-24 15:17:55 +0000 uma: Enqueue full buckets in FIFO order when KASAN is configured We want to defer reuse of free objects, and this is a trivial way to promote that. Suggested by: rlibby Reviewed by: rlibby, alc MFC after: 1 month Sponsored by: The FreeBSD Foundation Differential Revision: https://reviews.freebsd.org/D58312 (cherry picked from commit 492cfbe9e2f831fff290e019dae66345146978bd) --- sys/vm/uma_core.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) diff --git a/sys/vm/uma_core.c b/sys/vm/uma_core.c index e5bbb63776e8..30d1c1d1ac79 100644 --- a/sys/vm/uma_core.c +++ b/sys/vm/uma_core.c @@ -864,6 +864,8 @@ zone_put_bucket(uma_zone_t zone, int domain, uma_bucket_t bucket, void *udata, */ zdom->uzd_nitems += bucket->ub_cnt; if (__predict_true(zdom->uzd_nitems < zone->uz_bucket_max)) { + bool head; + if (ws) { zone_domain_imax_set(zdom, zdom->uzd_nitems); } else { @@ -882,8 +884,14 @@ zone_put_bucket(uma_zone_t zone, int domain, uma_bucket_t bucket, void *udata, /* * Try to promote reuse of recently used items. For items * protected by SMR, try to defer reuse to minimize polling. + * If KASAN is configured, try to defer reuse to improve UAF + * detection. */ - if (bucket->ub_seq == SMR_SEQ_INVALID) + head = bucket->ub_seq == SMR_SEQ_INVALID; +#ifdef KASAN + head = head && (zone->uz_flags & UMA_ZONE_NOKASAN) != 0; +#endif + if (head) STAILQ_INSERT_HEAD(&zdom->uzd_buckets, bucket, ub_link); else STAILQ_INSERT_TAIL(&zdom->uzd_buckets, bucket, ub_link);