From nobody Fri Oct 23 18:12:10 2026 X-Original-To: dev-commits-src-branches@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 4jBB1k6X9Wz6xPkn for ; Fri, 23 Oct 2026 18:12:10 +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) (No client certificate requested) by mx1.freebsd.org (Postfix) with ESMTPS id 4jBB1k4XQcz3JHg for ; Fri, 23 Oct 2026 18:12:10 +0000 (UTC) (envelope-from git@FreeBSD.org) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1792779130; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=meFFIZz5vmxjcW39GZB71kSTEyKDTP7InHzpy2WOJDg=; b=uz4ToUO4XnIEmtXSsIJwjSdbvHB3H8HXwBcgXXG+J+e/YmGPWcP6oRD8dKFcsfuvVQ4Lqe qn5ohe//JlJdmgvN1JNmEPgcqdt5yw13KCTb1tqPPPqnwRaGEO1aRWXP2cWwgZBH16XaPU Ml09KhuT/Pj99KLhRR1JL8/sfPwpkWDTkKASJjxHQY6E5RmwlQsBZ2BdhW/GECVRJ6cN1F rvTK5sLys6ZtyN5tzMYXFCScF55N94OQuBMv5YQ8GXCFUDMLXVfoN0yHIxc+9wYvqu4dU2 XAqUYfkhnoq0U8vWr6KkN0SseP2+NgVt9NctGPF0zmev3wNmaNJzZiQCbn5GQw== ARC-Seal: i=1; a=rsa-sha256; d=freebsd.org; s=dkim; cv=none; t=1792779130; b=ofFnm9NXFaCnGG65fRp18aYtqakgHC0110BA1a22y6Rwb8N+i9B9UVBcF/a9wBdwXPDTty r/JbbwCdK77hpV7xRIXueNJFq4idaQOdtniaRzv/BSwmM+NOmC38R4pPYTJMVx89aSpAkf RW2+i2KFSryZ5qyCJcnRqXisNqU9/BsCNZGyhsWXq630GGZ2559oEK6/Vge51yNQvo9pg7 ca6D5kVHqoTT+sEFeYLIudZ1qj8hXHw88ClHNYGCZhC8Z2k4MKGavARvo88IR4BGGdu75Y j/tzgNgBgSjAQ8lCn7arwZbEujYgEERhGaQw6HD31WYUFsySb4gLtiEER0/Bww== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1792779130; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=meFFIZz5vmxjcW39GZB71kSTEyKDTP7InHzpy2WOJDg=; b=m4IUkzGctDSIENyt28TBd6dShuSWAEKrtkYf7gy5KLXNDWdauCDH+w8A1Egj2PzV06QSMz ZP9sYpmg6a50sQCn6hFaP64sMniPq+/QAFcIiDbamVpPzj68OvdJXMEpP4bg1izPhK2Fak xP8+/qedC6WU4KwO5iVEZgTba1CB4Z4Lu0Xdcf6NuY2xAvvKPvjqqFCoNsgf0rrmgktqXh z0vXL/38ukC/CObwwuxMzWFpCWLlzBdpoyPMR32si1ib+yem0dM0mdAKmu2H19NVl6TPJc 7H35cYXK/v99DjW4ls2x/IfQh7ROHHqVJzMIzS5xrHIijdLKW/zJ4Q5lsrYlTg== ARC-Authentication-Results: i=1; mx1.freebsd.org; none Received: from gitrepo.freebsd.org (gitrepo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:5]) by mxrelay.nyi.freebsd.org (Postfix) with ESMTP id 4jBB1k3wYnzhjW for ; Fri, 23 Oct 2026 18:12:10 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from git (uid 1279) (envelope-from git@FreeBSD.org) id 1dc18 by gitrepo.freebsd.org (DragonFly Mail Agent v0.13+ on gitrepo.freebsd.org); Fri, 23 Oct 2026 18:12:10 +0000 To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-branches@FreeBSD.org Cc: Lukas Book From: Michael Tuexen Subject: git: 0b3f85d53e29 - stable/15 - sctp: hold tcp lock when calling sctp_calc_rwnd() List-Archive: https://lists.freebsd.org/archives/dev-commits-src-branches X-BeenThere: dev-commits-src-branches@freebsd.org Sender: owner-dev-commits-src-branches@FreeBSD.org List-Id: Commits to the stable branches of the FreeBSD src repository 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: tuexen X-Git-Repository: src X-Git-Refname: refs/heads/stable/15 X-Git-Reftype: branch X-Git-Commit: 0b3f85d53e2914c5ae167cada0c04f8dd65be71e Auto-Submitted: auto-generated Date: Fri, 23 Oct 2026 18:12:10 +0000 Message-Id: <6adba37a.1dc18.60f3b6b4@gitrepo.freebsd.org> The branch stable/15 has been updated by tuexen: URL: https://cgit.FreeBSD.org/src/commit/?id=0b3f85d53e2914c5ae167cada0c04f8dd65be71e commit 0b3f85d53e2914c5ae167cada0c04f8dd65be71e Author: Lukas Book AuthorDate: 2026-10-11 20:00:06 +0000 Commit: Michael Tuexen CommitDate: 2026-10-23 18:11:00 +0000 sctp: hold tcp lock when calling sctp_calc_rwnd() This was done in all code paths except one. Fix this to avoid race conditions. Reported by: syzbot+2e2dc35c0e24a74663a7@syzkaller.appspotmail.com Reviewed by: tuexen (cherry picked from commit 429f2fb48b92011d07798e681d96aa628fd8e387) --- sys/netinet/sctputil.c | 35 ++++++++++++++--------------------- 1 file changed, 14 insertions(+), 21 deletions(-) diff --git a/sys/netinet/sctputil.c b/sys/netinet/sctputil.c index ddfa71d5c7ed..119fad13c3f0 100644 --- a/sys/netinet/sctputil.c +++ b/sys/netinet/sctputil.c @@ -5452,9 +5452,20 @@ sctp_user_rcvd(struct sctp_tcb *stcb, uint32_t *freed_so_far, int hold_rlock, goto out; } atomic_add_int(&stcb->freed_by_sorcv_sincelast, *freed_so_far); - /* Have you have freed enough to look */ *freed_so_far = 0; - /* Yep, its worth a look and the lock overhead */ + if (hold_rlock) { + SCTP_INP_READ_UNLOCK(stcb->sctp_ep); + r_unlocked = 1; + } + if (stcb->asoc.state & SCTP_STATE_ABOUT_TO_BE_FREED) { + goto out; + } + SCTP_TCB_LOCK(stcb); + if (stcb->asoc.state & SCTP_STATE_ABOUT_TO_BE_FREED) { + /* No reports here */ + SCTP_TCB_UNLOCK(stcb); + goto out; + } /* Figure out what the rwnd would be */ rwnd = sctp_calc_rwnd(stcb, &stcb->asoc); @@ -5464,24 +5475,6 @@ sctp_user_rcvd(struct sctp_tcb *stcb, uint32_t *freed_so_far, int hold_rlock, dif = 0; } if (dif >= rwnd_req) { - if (hold_rlock) { - SCTP_INP_READ_UNLOCK(stcb->sctp_ep); - r_unlocked = 1; - } - if (stcb->asoc.state & SCTP_STATE_ABOUT_TO_BE_FREED) { - /* - * One last check before we allow the guy possibly - * to get in. There is a race, where the guy has not - * reached the gate. In that case - */ - goto out; - } - SCTP_TCB_LOCK(stcb); - if (stcb->asoc.state & SCTP_STATE_ABOUT_TO_BE_FREED) { - /* No reports here */ - SCTP_TCB_UNLOCK(stcb); - goto out; - } SCTP_STAT_INCR(sctps_wu_sacks_sent); NET_EPOCH_ENTER(et); sctp_send_sack(stcb, SCTP_SO_LOCKED); @@ -5492,11 +5485,11 @@ sctp_user_rcvd(struct sctp_tcb *stcb, uint32_t *freed_so_far, int hold_rlock, NET_EPOCH_EXIT(et); sctp_timer_stop(SCTP_TIMER_TYPE_RECV, stcb->sctp_ep, stcb, NULL, SCTP_FROM_SCTPUTIL + SCTP_LOC_6); - SCTP_TCB_UNLOCK(stcb); } else { /* Update how much we have pending */ stcb->freed_by_sorcv_sincelast = dif; } + SCTP_TCB_UNLOCK(stcb); out: if (so && r_unlocked && hold_rlock) { SCTP_INP_READ_LOCK(stcb->sctp_ep);