From nobody Sun Oct 11 20:05:21 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 4j2s5y6THfz6vrh6 for ; Sun, 11 Oct 2026 20:05:26 +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 "YR2" (not verified)) by mx1.freebsd.org (Postfix) with ESMTPS id 4j2s5y4Qn4z4jJX for ; Sun, 11 Oct 2026 20:05:26 +0000 (UTC) (envelope-from git@FreeBSD.org) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1791749126; 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=llUEAtJttdsWzm9pfTCOuoRalXszuRiTES6g5x0RqGw=; b=H385rJq0u1Vl3aVtGGJyBpeR/KZqtIu+Jdl+A72pmnhBrQAk0ZI/g295Tqc4nXh5/GqVJI /xb7VUEipwJ9M3glK7zEeFhBQy+6Jp5xFQSvBdaLt+nLHfMQ1JqmJekarCPWcmZ35Kyh5L gmnmUtTJ7H48XhtnwNDwNVP8RHLlkSXY8fHCmTXKf6S0xHV900dA2FwFWRo8CzkXlZ4QZR Sr5L7ycg5a0hpLBqmcvPcdOylJUPHwIZGfEKRrMHAKypxLgsx9pkifmG12ghvoUMuqbWY1 MnhpxtXKf8Zvdzjl2eN7sOCjv6lslWVZfIa2Tb7H2qBYM1IEmXl532zRC4afXQ== ARC-Seal: i=1; a=rsa-sha256; d=freebsd.org; s=dkim; cv=none; t=1791749126; b=vM2BpnG7yeGvh3GlY177CuAX3FmtRUy39BhqDNFR3IwQ7j+zfUu+YHGr8zLn4Azl2J0o3Y Em7Sivnq4xZCscJKrMo3mt6MTtJxm/sAFIMLEyUqHDI/P6gS9lvDr5aNfQh3LM3n3mD+To c86eHKeXX4ZR+UMthj8Qh99cRjO2ccB7rFk/hu5EhXv5KJe++HKpUKLvRT4iXWYTVPasgU 927jClO5JT+cfg2SJyYSsOEkyCuvlx7oeG+j5oW3/wDLFG3fqS7q0+Eux7kpoX05aVNUXu T5acOCZr+mQ8VK5S6yBj0TsvWC1sJJos9KE+q6GCmSUjmB26eK8Ou0lTagzm1A== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1791749126; 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=llUEAtJttdsWzm9pfTCOuoRalXszuRiTES6g5x0RqGw=; b=jaX0MbG/17kBx/tzkh5zbO2I2j4fD18uzF9SaE0AikCSKkjorN/qMC04TsJdQjEfc/xLj7 KGCgcb4O1KSOjKdQupkChbbTFjEZgUfl2Xoni6LVXTe3iuOIxGM7kRxeOTtkJe0U4XoA5r sv2+nDxLuuPaoHQnMJVhA1/Uhx5Kx4fQBehLI82XhJjavO7GgfcHKgG7sYdUnotUSlBulL 0UQYide8CeIYyKFnaArWdTfDxGs2YhMPEtAU1ATr5QOFpTdYESzz+JnIVLbstEJo+ydzN0 PyAI92WWo9ZcV1AtU4KeIqO6V+uSB+GiEo8sS+lr/ujHKZKKUMsbYKbcuWbI1A== 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 4j2s5y3Ffbzwfq for ; Sun, 11 Oct 2026 20:05:26 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from git (uid 1279) (envelope-from git@FreeBSD.org) id 3f2da by gitrepo.freebsd.org (DragonFly Mail Agent v0.13+ on gitrepo.freebsd.org); Sun, 11 Oct 2026 20:05:21 +0000 To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-main@FreeBSD.org Cc: Lukas Book From: Michael Tuexen Subject: git: 429f2fb48b92 - main - sctp: hold tcp lock when calling sctp_calc_rwnd() List-Archive: https://lists.freebsd.org/archives/dev-commits-src-all X-BeenThere: dev-commits-src-all@freebsd.org Sender: owner-dev-commits-src-all@FreeBSD.org List-Id: Commit messages for all branches of the 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/main X-Git-Reftype: branch X-Git-Commit: 429f2fb48b92011d07798e681d96aa628fd8e387 Auto-Submitted: auto-generated Date: Sun, 11 Oct 2026 20:05:21 +0000 Message-Id: <6acbec01.3f2da.79b52d63@gitrepo.freebsd.org> The branch main has been updated by tuexen: URL: https://cgit.FreeBSD.org/src/commit/?id=429f2fb48b92011d07798e681d96aa628fd8e387 commit 429f2fb48b92011d07798e681d96aa628fd8e387 Author: Lukas Book AuthorDate: 2026-10-11 20:00:06 +0000 Commit: Michael Tuexen CommitDate: 2026-10-11 20:00:06 +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 MFC after: 1 week MFC to: stable/14 MFC to: stable/15 --- 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);