From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 77987C433FE for ; Wed, 30 Nov 2022 18:30:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229901AbiK3SaM (ORCPT ); Wed, 30 Nov 2022 13:30:12 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35610 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229978AbiK3SaB (ORCPT ); Wed, 30 Nov 2022 13:30:01 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 09AE08D673 for ; Wed, 30 Nov 2022 10:30:00 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id BE604B81CA3 for ; Wed, 30 Nov 2022 18:29:58 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2394AC433C1; Wed, 30 Nov 2022 18:29:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1669832997; bh=bQNqP7z+aHLa8KRBrxIYdiutNdROFHNEvXybjt2pv4s=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=sC/KEGLDRviLLRI/Wq1+D9inDbjK/l4rEFTkZSIjq42ABJLsBHno5DRI5Cq+WFmyE NusMm5tUmz1dPbAWz9nE1kHtWzQmYstuOOI5jF8CybNx9wATvU0k/UZ3epHLLWD/vS AaSn73bt8GFKFBj36Uje1EDRuIffFShRgwAbB5Mo= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Xiubo Li , Ilya Dryomov , Sasha Levin Subject: [PATCH 5.10 115/162] ceph: fix NULL pointer dereference for req->r_session Date: Wed, 30 Nov 2022 19:23:16 +0100 Message-Id: <20221130180531.607652634@linuxfoundation.org> X-Mailer: git-send-email 2.38.1 In-Reply-To: <20221130180528.466039523@linuxfoundation.org> References: <20221130180528.466039523@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Xiubo Li [ Upstream commit 5bd76b8de5b74fa941a6eafee87728a0fe072267 ] The request's r_session maybe changed when it was forwarded or resent. Both the forwarding and resending cases the requests will be protected by the mdsc->mutex. Cc: stable@vger.kernel.org Link: https://bugzilla.redhat.com/show_bug.cgi?id=2137955 Signed-off-by: Xiubo Li Reviewed-by: Ilya Dryomov Signed-off-by: Ilya Dryomov Signed-off-by: Sasha Levin --- fs/ceph/caps.c | 48 ++++++++++++------------------------------------ 1 file changed, 12 insertions(+), 36 deletions(-) diff --git a/fs/ceph/caps.c b/fs/ceph/caps.c index 668be87ffee6..51562d36fa83 100644 --- a/fs/ceph/caps.c +++ b/fs/ceph/caps.c @@ -2297,7 +2297,6 @@ static int unsafe_request_wait(struct inode *inode) struct ceph_mds_client *mdsc = ceph_sb_to_client(inode->i_sb)->mdsc; struct ceph_inode_info *ci = ceph_inode(inode); struct ceph_mds_request *req1 = NULL, *req2 = NULL; - unsigned int max_sessions; int ret, err = 0; spin_lock(&ci->i_unsafe_lock); @@ -2315,28 +2314,24 @@ static int unsafe_request_wait(struct inode *inode) } spin_unlock(&ci->i_unsafe_lock); - /* - * The mdsc->max_sessions is unlikely to be changed - * mostly, here we will retry it by reallocating the - * sessions array memory to get rid of the mdsc->mutex - * lock. - */ -retry: - max_sessions = mdsc->max_sessions; - /* * Trigger to flush the journal logs in all the relevant MDSes * manually, or in the worst case we must wait at most 5 seconds * to wait the journal logs to be flushed by the MDSes periodically. */ - if ((req1 || req2) && likely(max_sessions)) { - struct ceph_mds_session **sessions = NULL; - struct ceph_mds_session *s; + if (req1 || req2) { struct ceph_mds_request *req; + struct ceph_mds_session **sessions; + struct ceph_mds_session *s; + unsigned int max_sessions; int i; + mutex_lock(&mdsc->mutex); + max_sessions = mdsc->max_sessions; + sessions = kcalloc(max_sessions, sizeof(s), GFP_KERNEL); if (!sessions) { + mutex_unlock(&mdsc->mutex); err = -ENOMEM; goto out; } @@ -2348,16 +2343,6 @@ static int unsafe_request_wait(struct inode *inode) s = req->r_session; if (!s) continue; - if (unlikely(s->s_mds >= max_sessions)) { - spin_unlock(&ci->i_unsafe_lock); - for (i = 0; i < max_sessions; i++) { - s = sessions[i]; - if (s) - ceph_put_mds_session(s); - } - kfree(sessions); - goto retry; - } if (!sessions[s->s_mds]) { s = ceph_get_mds_session(s); sessions[s->s_mds] = s; @@ -2370,16 +2355,6 @@ static int unsafe_request_wait(struct inode *inode) s = req->r_session; if (!s) continue; - if (unlikely(s->s_mds >= max_sessions)) { - spin_unlock(&ci->i_unsafe_lock); - for (i = 0; i < max_sessions; i++) { - s = sessions[i]; - if (s) - ceph_put_mds_session(s); - } - kfree(sessions); - goto retry; - } if (!sessions[s->s_mds]) { s = ceph_get_mds_session(s); sessions[s->s_mds] = s; @@ -2391,11 +2366,12 @@ static int unsafe_request_wait(struct inode *inode) /* the auth MDS */ spin_lock(&ci->i_ceph_lock); if (ci->i_auth_cap) { - s = ci->i_auth_cap->session; - if (!sessions[s->s_mds]) - sessions[s->s_mds] = ceph_get_mds_session(s); + s = ci->i_auth_cap->session; + if (!sessions[s->s_mds]) + sessions[s->s_mds] = ceph_get_mds_session(s); } spin_unlock(&ci->i_ceph_lock); + mutex_unlock(&mdsc->mutex); /* send flush mdlog request to MDSes */ for (i = 0; i < max_sessions; i++) { -- 2.35.1