From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D733C4E01FA; Wed, 30 Sep 2026 18:33:43 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790793225; cv=none; b=K0An7ZPgAqUtz/t+kZr/0laRmBz4qWBDWsZEd8lLM0K7Rgtk7H6MzPh/P6/9dJSR8NFZKNJU/ml8/Mf5tjxwE5H2GaQt/2VqrEEfTletv9ijb/RmTnYN+CDDYOAwFxBkDuUTv98HrX7b4rDXBs//3ZAW0MOKqrxgi94/q87MySI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790793225; c=relaxed/simple; bh=AImmCSMpa1OIqTTOUZ4FijSieeBv23jsFznx5wwVFRM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=a5m/WFCb+TeCuhTCuAnv0ZYrbSpqp6QxLrD16d4R3J28YDdtuwN8fKI5bkilT3jk/0vwUbZ1S09cD41pp6osRn94fbQvIUX4Q8/CzXFb3jX2DtBvUSv6mo0tqUdAEdYr2RLHpO8i0bLmx9mFeooRCFSWnc+K0xFemmO+ffYdZdo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=aOuUHcQL; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="aOuUHcQL" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 02D5E1F000FF; Wed, 30 Sep 2026 18:33:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1790793223; bh=Mpwa38OOO1NxaQbLZV5VvMDvkZnAz2ooNNEXXq4gtpU=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=aOuUHcQLaLChn5caV5ReO0CScwkWye4/oPdNp/EG4LWBDuHcYFrD8f/SS0TPdIzuc SVaZvDKiXavYdGbIsWOhWho+9AUkjk6oat5OWKdRcRKs+9+MvUtA6H9xET+//5rzG2 MSQxk+FPQS2N7xiQ8XWiUwZH4SQiPykmgJ7czI7k= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Mahanta Jambigi , Sidraya Jayagond , Dust Li , Jakub Kicinski , Sasha Levin Subject: [PATCH 6.18 180/395] net/smc: fix UAF on lgr list traversal in smcr_port_err() Date: Wed, 30 Sep 2026 17:27:22 +0200 Message-ID: <20260930152344.557178992@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260930152340.591469096@linuxfoundation.org> References: <20260930152340.591469096@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Sidraya Jayagond [ Upstream commit 61cb282fe97b3b0ba32ca09417a693162bf4ae3f ] smcr_port_err() traverses smc_lgr_list.list without holding smc_lgr_list.lock, allowing a concurrent smc_lgr_terminate_sched() to free an lgr while it is still being dereferenced. Hold smc_lgr_list.lock across the traversal. Update smc_ib_gid_check() to call smcr_port_err() after releasing the lock. Fixes: 541afa10c126 ("net/smc: add smcr_port_err() and smcr_link_down() processing") Reviewed-by: Mahanta Jambigi Signed-off-by: Sidraya Jayagond Reviewed-by: Dust Li Link: https://patch.msgid.link/20260922073149.474762-1-sidraya@linux.ibm.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- net/smc/smc_core.c | 2 ++ net/smc/smc_ib.c | 10 ++++++++-- 2 files changed, 10 insertions(+), 2 deletions(-) diff --git a/net/smc/smc_core.c b/net/smc/smc_core.c index 34fa809e95047..fff84df00cab3 100644 --- a/net/smc/smc_core.c +++ b/net/smc/smc_core.c @@ -1835,6 +1835,7 @@ void smcr_port_err(struct smc_ib_device *smcibdev, u8 ibport) struct smc_link_group *lgr, *n; int i; + spin_lock_bh(&smc_lgr_list.lock); list_for_each_entry_safe(lgr, n, &smc_lgr_list.list, list) { if (strncmp(smcibdev->pnetid[ibport - 1], lgr->pnet_id, SMC_MAX_PNETID_LEN)) @@ -1849,6 +1850,7 @@ void smcr_port_err(struct smc_ib_device *smcibdev, u8 ibport) smcr_link_down_cond_sched(lnk); } } + spin_unlock_bh(&smc_lgr_list.lock); } static void smc_link_down_work(struct work_struct *work) diff --git a/net/smc/smc_ib.c b/net/smc/smc_ib.c index 0052f02756ebb..845f15ed06bf1 100644 --- a/net/smc/smc_ib.c +++ b/net/smc/smc_ib.c @@ -333,6 +333,7 @@ static bool smc_ib_check_link_gid(u8 gid[SMC_GID_SIZE], bool smcrv2, static void smc_ib_gid_check(struct smc_ib_device *smcibdev, u8 ibport) { struct smc_link_group *lgr; + bool stale_gid = false; int i; spin_lock_bh(&smc_lgr_list.lock); @@ -348,11 +349,16 @@ static void smc_ib_gid_check(struct smc_ib_device *smcibdev, u8 ibport) continue; if (!smc_ib_check_link_gid(lgr->lnk[i].gid, lgr->smc_version == SMC_V2, - smcibdev, ibport)) - smcr_port_err(smcibdev, ibport); + smcibdev, ibport)) { + stale_gid = true; + goto out; + } } } +out: spin_unlock_bh(&smc_lgr_list.lock); + if (stale_gid) + smcr_port_err(smcibdev, ibport); } static int smc_ib_remember_port_attr(struct smc_ib_device *smcibdev, u8 ibport) -- 2.53.0