From nobody Thu Nov 28 12:55:09 2024 Received: from smtp.cecloud.com (unknown [1.203.97.240]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 629371BC9F3; Tue, 1 Oct 2024 07:27:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=1.203.97.240 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1727767673; cv=none; b=DmBlzIRzgjtqkyPEfRr0IAyIINbEKVUcwwhuJs62kRLM00OWGhSyT9q/n9Gr+R3pSIP7bqSqPQ+i0olj7I3RMtpc04vCXUwue+RJoxnZol/kcp5UCDwyFzJ6rZVjvPqV2ezAF1eGtCLy4NL7rGt0Ux6Yt05yrLQh/PLhVuzMdsI= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1727767673; c=relaxed/simple; bh=MWIrzzbu8UDNEEj2AkbRYnFLNOGGcry28HItKz9w8ww=; h=From:To:Cc:Subject:Date:Message-Id:MIME-Version; b=H3ovyZY0DYlthEzUykGxG47U+ZEI3PWU+uJOjPZr2gS8ncx5wgRNWWqrJtE48/HehbX1H9nI8RMuinI7cbe7skgDmhp50CVNgkjHyhmMxNC0hR5zgAp19mbLIWpfLsQDv/390Dbg0qCVXduSAbDJ1vO4wDmOLJxE216m2dZaE6g= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=cestc.cn; spf=pass smtp.mailfrom=cestc.cn; arc=none smtp.client-ip=1.203.97.240 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=cestc.cn Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=cestc.cn Received: from localhost (localhost [127.0.0.1]) by smtp.cecloud.com (Postfix) with ESMTP id 6A392900112; Tue, 1 Oct 2024 15:21:17 +0800 (CST) X-MAIL-GRAY: 0 X-MAIL-DELIVERY: 1 X-SKE-CHECKED: 1 X-ANTISPAM-LEVEL: 2 Received: from localhost.localdomain.localdomain (unknown [115.193.80.205]) by smtp.cecloud.com (postfix) whith ESMTP id P1340312T281473089204592S1727767276687585_; Tue, 01 Oct 2024 15:21:17 +0800 (CST) X-IP-DOMAINF: 1 X-RL-SENDER: zhangyanjun@cestc.cn X-SENDER: zhangyanjun@cestc.cn X-LOGIN-NAME: zhangyanjun@cestc.cn X-FST-TO: trondmy@kernel.org X-RCPT-COUNT: 7 X-LOCAL-RCPT-COUNT: 1 X-MUTI-DOMAIN-COUNT: 0 X-SENDER-IP: 115.193.80.205 X-ATTACHMENT-NUM: 0 X-UNIQUE-TAG: X-System-Flag: 0 From: zhangyanjun@cestc.cn To: trondmy@kernel.org, anna@kernel.org, Markus.Elfring@web.de Cc: linux-nfs@vger.kernel.org, linux-kernel@vger.kernel.org, Yanjun Zhang , Trond Myklebust Subject: [PATCH v4] NFSv4: fix possible NULL-pointer dereference in nfs42_complete_copies() Date: Tue, 1 Oct 2024 15:21:01 +0800 Message-Id: <20241001072101.3556-1-zhangyanjun@cestc.cn> X-Mailer: git-send-email 2.31.1 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: Yanjun Zhang On the node of an NFS client, some files saved in the mountpoint of the NFS server were coping data within the same server. Accidentally, the=20 nfs42_complete_copies() got a NULL-pointer dereference crash with the=20 following syslog: [232064.838881] NFSv4: state recovery failed for open file nfs/pvc-12b5200d= -cd0f-46a3-b9f0-af8f4fe0ef64.qcow2, error =3D -116 [232064.839360] NFSv4: state recovery failed for open file nfs/pvc-12b5200d= -cd0f-46a3-b9f0-af8f4fe0ef64.qcow2, error =3D -116 [232066.588183] Unable to handle kernel NULL pointer dereference at virtual= address 0000000000000058 [232066.588586] Mem abort info: [232066.588701] ESR =3D 0x0000000096000007 [232066.588862] EC =3D 0x25: DABT (current EL), IL =3D 32 bits [232066.589084] SET =3D 0, FnV =3D 0 [232066.589216] EA =3D 0, S1PTW =3D 0 [232066.589340] FSC =3D 0x07: level 3 translation fault [232066.589559] Data abort info: [232066.589683] ISV =3D 0, ISS =3D 0x00000007 [232066.589842] CM =3D 0, WnR =3D 0 [232066.589967] user pgtable: 64k pages, 48-bit VAs, pgdp=3D00002000956ff400 [232066.590231] [0000000000000058] pgd=3D08001100ae100003, p4d=3D08001100ae= 100003, pud=3D08001100ae100003, pmd=3D08001100b3c00003, pte=3D0000000000000= 000 [232066.590757] Internal error: Oops: 96000007 [#1] SMP [232066.590958] Modules linked in: rpcsec_gss_krb5 auth_rpcgss nfsv4 dns_re= solver nfs lockd grace fscache netfs ocfs2_dlmfs ocfs2_stack_o2cb ocfs2_dlm= vhost_net vhost vhost_iotlb tap tun ipt_rpfilter xt_multiport ip_set_hash_= ip ip_set_hash_net xfrm_interface xfrm6_tunnel tunnel4 tunnel6 esp4 ah4 wir= eguard libcurve25519_generic veth xt_addrtype xt_set nf_conntrack_netlink i= p_set_hash_ipportnet ip_set_hash_ipportip ip_set_bitmap_port ip_set_hash_ip= port dummy ip_set ip_vs_sh ip_vs_wrr ip_vs_rr ip_vs iptable_filter sch_ingr= ess nfnetlink_cttimeout vport_gre ip_gre ip_tunnel gre vport_geneve geneve = vport_vxlan vxlan ip6_udp_tunnel udp_tunnel openvswitch nf_conncount dm_rou= nd_robin dm_service_time dm_multipath xt_nat xt_MASQUERADE nft_chain_nat nf= _nat xt_mark xt_conntrack xt_comment nft_compat nft_counter nf_tables nfnet= link ocfs2 ocfs2_nodemanager ocfs2_stackglue iscsi_tcp libiscsi_tcp libiscs= i scsi_transport_iscsi ipmi_ssif nbd overlay 8021q garp mrp bonding tls rfk= ill sunrpc ext4 mbcache jbd2 [232066.591052] vfat fat cas_cache cas_disk ses enclosure scsi_transport_s= as sg acpi_ipmi ipmi_si ipmi_devintf ipmi_msghandler ip_tables vfio_pci vfi= o_pci_core vfio_virqfd vfio_iommu_type1 vfio dm_mirror dm_region_hash dm_lo= g dm_mod nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 br_netfilter bridge stp= llc fuse xfs libcrc32c ast drm_vram_helper qla2xxx drm_kms_helper syscopya= rea crct10dif_ce sysfillrect ghash_ce sysimgblt sha2_ce fb_sys_fops cec sha= 256_arm64 sha1_ce drm_ttm_helper ttm nvme_fc igb sbsa_gwdt nvme_fabrics drm= nvme_core i2c_algo_bit i40e scsi_transport_fc megaraid_sas aes_neon_bs [232066.596953] CPU: 6 PID: 4124696 Comm: 10.253.166.125- Kdump: loaded Not= tainted 5.15.131-9.cl9_ocfs2.aarch64 #1 [232066.597356] Hardware name: Great Wall .\x93\x8e...RF6260 V5/GWMSSE2GL1T= , BIOS T656FBE_V3.0.18 2024-01-06 [232066.597721] pstate: 20400009 (nzCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE= =3D--) [232066.598034] pc : nfs4_reclaim_open_state+0x220/0x800 [nfsv4] [232066.598327] lr : nfs4_reclaim_open_state+0x12c/0x800 [nfsv4] [232066.598595] sp : ffff8000f568fc70 [232066.598731] x29: ffff8000f568fc70 x28: 0000000000001000 x27: ffff21003d= b33000 [232066.599030] x26: ffff800005521ae0 x25: ffff0100f98fa3f0 x24: 0000000000= 000001 [232066.599319] x23: ffff800009920008 x22: ffff21003db33040 x21: ffff21003d= b33050 [232066.599628] x20: ffff410172fe9e40 x19: ffff410172fe9e00 x18: 0000000000= 000000 [232066.599914] x17: 0000000000000000 x16: 0000000000000004 x15: 0000000000= 000000 [232066.600195] x14: 0000000000000000 x13: ffff800008e685a8 x12: 00000000ea= c0c6e6 [232066.600498] x11: 0000000000000000 x10: 0000000000000008 x9 : ffff800005= 4e5828 [232066.600784] x8 : 00000000ffffffbf x7 : 0000000000000001 x6 : 000000000a= 9eb14a [232066.601062] x5 : 0000000000000000 x4 : ffff70ff8a14a800 x3 : 0000000000= 000058 [232066.601348] x2 : 0000000000000001 x1 : 54dce46366daa6c6 x0 : 0000000000= 000000 [232066.601636] Call trace: [232066.601749] nfs4_reclaim_open_state+0x220/0x800 [nfsv4] [232066.601998] nfs4_do_reclaim+0x1b8/0x28c [nfsv4] [232066.602218] nfs4_state_manager+0x928/0x10f0 [nfsv4] [232066.602455] nfs4_run_state_manager+0x78/0x1b0 [nfsv4] [232066.602690] kthread+0x110/0x114 [232066.602830] ret_from_fork+0x10/0x20 [232066.602985] Code: 1400000d f9403f20 f9402e61 91016003 (f9402c00) [232066.603284] SMP: stopping secondary CPUs [232066.606936] Starting crashdump kernel... [232066.607146] Bye! Analysing the vmcore, we know that nfs4_copy_state listed by destination nfs_server->ss_copies was added by the field copies in handle_async_copy(), and we found a waiting copy process with the stack as: PID: 3511963 TASK: ffff710028b47e00 CPU: 0 COMMAND: "cp" #0 [ffff8001116ef740] __switch_to at ffff8000081b92f4 #1 [ffff8001116ef760] __schedule at ffff800008dd0650 #2 [ffff8001116ef7c0] schedule at ffff800008dd0a00 #3 [ffff8001116ef7e0] schedule_timeout at ffff800008dd6aa0 #4 [ffff8001116ef860] __wait_for_common at ffff800008dd166c #5 [ffff8001116ef8e0] wait_for_completion_interruptible at ffff800008dd1898 #6 [ffff8001116ef8f0] handle_async_copy at ffff8000055142f4 [nfsv4] #7 [ffff8001116ef970] _nfs42_proc_copy at ffff8000055147c8 [nfsv4] #8 [ffff8001116efa80] nfs42_proc_copy at ffff800005514cf0 [nfsv4] #9 [ffff8001116efc50] __nfs4_copy_file_range.constprop.0 at ffff8000054ed6= 94 [nfsv4] The NULL-pointer dereference was due to nfs42_complete_copies() listed the nfs_server->ss_copies by the field ss_copies of nfs4_copy_state. So the nfs4_copy_state address ffff0100f98fa3f0 was offset by 0x10 and the data accessed through this pointer was also incorrect. Generally, the ordered list nfs4_state_owner->so_states indicate open(O_RDWR) or open(O_WRITE) states are reclaimed firstly by nfs4_reclaim_open_state(). When destination state reclaim is failed with NFS_STATE_RECOVERY_FAILED and copies are not deleted in nfs_server->ss_copies, the source state may be passed to the nfs42_complete_copies() process earlier, resulting in this crash scene finally. To solve this issue, we add a list_head nfs_server->ss_src_copies for a server-to-server copy specially. Fixes: 0e65a32c8a56 ("NFS: handle source server reboot") Signed-off-by: Yanjun Zhang Reviewed-by: Trond Myklebust --- v2: - add an initialiser for the new list in nfs_alloc_server(). - change the new list name from ds_copies to ss_src_copies. v3: - correct the commit ID of Fixes tags. - append parentheses to any function names. - modify the title and text to get smaller line lengths. v4: - add Reviewed-by tags and patch changelogs. - adjust the patch description more accurately. fs/nfs/client.c | 1 + fs/nfs/nfs42proc.c | 2 +- fs/nfs/nfs4state.c | 2 +- include/linux/nfs_fs_sb.h | 1 + 4 files changed, 4 insertions(+), 2 deletions(-) diff --git a/fs/nfs/client.c b/fs/nfs/client.c index 8286edd60..c49d5cce5 100644 --- a/fs/nfs/client.c +++ b/fs/nfs/client.c @@ -983,6 +983,7 @@ struct nfs_server *nfs_alloc_server(void) INIT_LIST_HEAD(&server->layouts); INIT_LIST_HEAD(&server->state_owners_lru); INIT_LIST_HEAD(&server->ss_copies); + INIT_LIST_HEAD(&server->ss_src_copies); =20 atomic_set(&server->active, 0); =20 diff --git a/fs/nfs/nfs42proc.c b/fs/nfs/nfs42proc.c index 28704f924..531c9c20e 100644 --- a/fs/nfs/nfs42proc.c +++ b/fs/nfs/nfs42proc.c @@ -218,7 +218,7 @@ static int handle_async_copy(struct nfs42_copy_res *res, =20 if (dst_server !=3D src_server) { spin_lock(&src_server->nfs_client->cl_lock); - list_add_tail(©->src_copies, &src_server->ss_copies); + list_add_tail(©->src_copies, &src_server->ss_src_copies); spin_unlock(&src_server->nfs_client->cl_lock); } =20 diff --git a/fs/nfs/nfs4state.c b/fs/nfs/nfs4state.c index 877f682b4..00516982b 100644 --- a/fs/nfs/nfs4state.c +++ b/fs/nfs/nfs4state.c @@ -1596,7 +1596,7 @@ static void nfs42_complete_copies(struct nfs4_state_o= wner *sp, struct nfs4_state complete(©->completion); } } - list_for_each_entry(copy, &sp->so_server->ss_copies, src_copies) { + list_for_each_entry(copy, &sp->so_server->ss_src_copies, src_copies) { if ((test_bit(NFS_CLNT_SRC_SSC_COPY_STATE, &state->flags) && !nfs4_stateid_match_other(&state->stateid, ©->parent_src_state->stateid))) diff --git a/include/linux/nfs_fs_sb.h b/include/linux/nfs_fs_sb.h index 1df86ab98..793a4a610 100644 --- a/include/linux/nfs_fs_sb.h +++ b/include/linux/nfs_fs_sb.h @@ -240,6 +240,7 @@ struct nfs_server { struct list_head layouts; struct list_head delegations; struct list_head ss_copies; + struct list_head ss_src_copies; =20 unsigned long delegation_gen; unsigned long mig_gen; --=20 2.31.1