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 7E699501285; Wed, 30 Sep 2026 17:29:00 +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=1790789341; cv=none; b=FPOcT7orqqd28I/kHG5QdqZkD8KAhXU2EeYUfJClOr9slvPgsSjetSpDkXkx3LWsfWrmkx7ojFFK3GH6Ll4eq3eK37t+u9T3ICVRMyrso8ICnFntEwRGtGz6PcYZGg60BvwuOy2PpPaXCZlt+IV+BJrjCHsxQVJemfQzfbLUmkE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790789341; c=relaxed/simple; bh=vOyWTzL73bkXTVvyuOtfFYyfda5CWpDoqJhC3pkI7kI=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=biOIoYnQXaqvlaB/hYepQUJhZ19SbaexJEeAqb2Nz4Aph/t9338i57KkeU42LbBn+kIcjS9NaBFKQmJk5qiUjSQsMzrUXEYXdDeuyHozOmsiY0p2tbG72O/C6LGFLG1ULRLIBwj8Fo0bnD3m+VHq6kWpX1XGlheMKIJiifUvH2c= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=QlFcM9bF; 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="QlFcM9bF" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C96751F000FF; Wed, 30 Sep 2026 17:28:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1790789340; bh=YejwSgJrkUw4qYgj1Ju7L+wCkiF6KznSiKA0q9rPmcg=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=QlFcM9bFfHjvcgoDDlNPj+pWgxB5vrvSoFHGddOQOFePF7oxNIiN6MbZgyk0vZRNZ EPlT9i7OzY7CDsKNnVfwP4J5h/yG5l6tZPWysAfDBhDnguKZUiax5q47/7LcdsejfJ XL6LhqdHy8hy7xfpny/dO2ZnlBCnv+BBFDUHbUWE= 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 6.12 441/877] net/smc: fix UAF on lgr list traversal in smcr_port_err() Date: Wed, 30 Sep 2026 17:22:32 +0200 Message-ID: <20260930152424.198856472@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260930152414.738996857@linuxfoundation.org> References: <20260930152414.738996857@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 6.12-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 ed0027ba66c75..e0bf348bd812e 100644 --- a/net/smc/smc_core.c +++ b/net/smc/smc_core.c @@ -1830,6 +1830,7 @@ 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)) @@ -1844,6 +1845,7 @@ 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 fc07fc4ed9986..0cca7b9ca044e 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