From 8e088a20dbe33919695a8082c0b32deb62d23b4a Mon Sep 17 00:00:00 2001 From: Olga Kornievskaia Date: Tue, 2 Apr 2024 14:41:38 -0400 Subject: [PATCH 1/2] SUNRPC: add a missing rpc_stat for TCP TLS Commit 1548036ef120 ("nfs: make the rpc_stat per net namespace") added functionality to specify rpc_stats function but missed adding it to the TCP TLS functionality. As the result, mounting with xprtsec=tls lead to the following kernel oops. [ 128.984192] Unable to handle kernel NULL pointer dereference at virtual address 000000000000001c [ 128.985058] Mem abort info: [ 128.985372] ESR = 0x0000000096000004 [ 128.985709] EC = 0x25: DABT (current EL), IL = 32 bits [ 128.986176] SET = 0, FnV = 0 [ 128.986521] EA = 0, S1PTW = 0 [ 128.986804] FSC = 0x04: level 0 translation fault [ 128.987229] Data abort info: [ 128.987597] ISV = 0, ISS = 0x00000004, ISS2 = 0x00000000 [ 128.988169] CM = 0, WnR = 0, TnD = 0, TagAccess = 0 [ 128.988811] GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0 [ 128.989302] user pgtable: 4k pages, 48-bit VAs, pgdp=0000000106c84000 [ 128.990048] [000000000000001c] pgd=0000000000000000, p4d=0000000000000000 [ 128.990736] Internal error: Oops: 0000000096000004 [#1] SMP [ 128.991168] Modules linked in: nfs_layout_nfsv41_files rpcsec_gss_krb5 auth_rpcgss nfsv4 dns_resolver nfs lockd grace netfs uinput dm_mod nft_fib_inet nft_fib_ipv4 nft_fib_ipv6 nft_fib nft_reject_inet nf_reject_ipv4 nf_reject_ipv6 nft_reject nft_ct nft_chain_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 rfkill ip_set nf_tables nfnetlink qrtr vsock_loopback vmw_vsock_virtio_transport_common vmw_vsock_vmci_transport vsock sunrpc vfat fat uvcvideo videobuf2_vmalloc videobuf2_memops uvc videobuf2_v4l2 videodev videobuf2_common mc vmw_vmci xfs libcrc32c e1000e crct10dif_ce ghash_ce sha2_ce vmwgfx nvme sha256_arm64 nvme_core sr_mod cdrom sha1_ce drm_ttm_helper ttm drm_kms_helper drm sg fuse [ 128.996466] CPU: 0 PID: 179 Comm: kworker/u4:26 Kdump: loaded Not tainted 6.8.0-rc6+ #12 [ 128.997226] Hardware name: VMware, Inc. VMware20,1/VBSA, BIOS VMW201.00V.21805430.BA64.2305221830 05/22/2023 [ 128.998084] Workqueue: xprtiod xs_tcp_tls_setup_socket [sunrpc] [ 128.998701] pstate: 81400005 (Nzcv daif +PAN -UAO -TCO +DIT -SSBS BTYPE=--) [ 128.999384] pc : call_start+0x74/0x138 [sunrpc] [ 128.999809] lr : __rpc_execute+0xb8/0x3e0 [sunrpc] [ 129.000244] sp : ffff8000832b3a00 [ 129.000508] x29: ffff8000832b3a00 x28: ffff800081ac79c0 x27: ffff800081ac7000 [ 129.001111] x26: 0000000004248060 x25: 0000000000000000 x24: ffff800081596008 [ 129.001757] x23: ffff80007b087240 x22: ffff00009a509d30 x21: 0000000000000000 [ 129.002345] x20: ffff000090075600 x19: ffff00009a509d00 x18: ffffffffffffffff [ 129.002912] x17: 733d4d4554535953 x16: 42555300312d746e x15: ffff8000832b3a88 [ 129.003464] x14: ffffffffffffffff x13: ffff8000832b3a7d x12: 0000000000000008 [ 129.004021] x11: 0101010101010101 x10: ffff8000150cb560 x9 : ffff80007b087c00 [ 129.004577] x8 : ffff00009a509de0 x7 : 0000000000000000 x6 : 00000000be8c4ee3 [ 129.005026] x5 : 0000000000000000 x4 : 0000000000000000 x3 : ffff000094d56680 [ 129.005425] x2 : ffff80007b0637f8 x1 : ffff000090075600 x0 : ffff00009a509d00 [ 129.005824] Call trace: [ 129.005967] call_start+0x74/0x138 [sunrpc] [ 129.006233] __rpc_execute+0xb8/0x3e0 [sunrpc] [ 129.006506] rpc_execute+0x160/0x1d8 [sunrpc] [ 129.006778] rpc_run_task+0x148/0x1f8 [sunrpc] [ 129.007204] tls_probe+0x80/0xd0 [sunrpc] [ 129.007460] rpc_ping+0x28/0x80 [sunrpc] [ 129.007715] rpc_create_xprt+0x134/0x1a0 [sunrpc] [ 129.007999] rpc_create+0x128/0x2a0 [sunrpc] [ 129.008264] xs_tcp_tls_setup_socket+0xdc/0x508 [sunrpc] [ 129.008583] process_one_work+0x174/0x3c8 [ 129.008813] worker_thread+0x2c8/0x3e0 [ 129.009033] kthread+0x100/0x110 [ 129.009225] ret_from_fork+0x10/0x20 [ 129.009432] Code: f0ffffc2 911fe042 aa1403e1 aa1303e0 (b9401c83) Fixes: 1548036ef120 ("nfs: make the rpc_stat per net namespace") Signed-off-by: Olga Kornievskaia Signed-off-by: Trond Myklebust --- net/sunrpc/xprtsock.c | 1 + 1 file changed, 1 insertion(+) diff --git a/net/sunrpc/xprtsock.c b/net/sunrpc/xprtsock.c index bb81050c870e..ea7bf1b4172d 100644 --- a/net/sunrpc/xprtsock.c +++ b/net/sunrpc/xprtsock.c @@ -2664,6 +2664,7 @@ static void xs_tcp_tls_setup_socket(struct work_struct *work) .xprtsec = { .policy = RPC_XPRTSEC_NONE, }, + .stats = upper_clnt->cl_stats, }; unsigned int pflags = current->flags; struct rpc_clnt *lower_clnt; From 24457f1be29f1e7042e50a7749f5c2dde8c433c8 Mon Sep 17 00:00:00 2001 From: Kuniyuki Iwashima Date: Thu, 4 Apr 2024 15:12:00 -0700 Subject: [PATCH 2/2] nfs: Handle error of rpc_proc_register() in nfs_net_init(). syzkaller reported a warning [0] triggered while destroying immature netns. rpc_proc_register() was called in init_nfs_fs(), but its error has been ignored since at least the initial commit 1da177e4c3f4 ("Linux-2.6.12-rc2"). Recently, commit d47151b79e32 ("nfs: expose /proc/net/sunrpc/nfs in net namespaces") converted the procfs to per-netns and made the problem more visible. Even when rpc_proc_register() fails, nfs_net_init() could succeed, and thus nfs_net_exit() will be called while destroying the netns. Then, remove_proc_entry() will be called for non-existing proc directory and trigger the warning below. Let's handle the error of rpc_proc_register() properly in nfs_net_init(). [0]: name 'nfs' WARNING: CPU: 1 PID: 1710 at fs/proc/generic.c:711 remove_proc_entry+0x1bb/0x2d0 fs/proc/generic.c:711 Modules linked in: CPU: 1 PID: 1710 Comm: syz-executor.2 Not tainted 6.8.0-12822-gcd51db110a7e #12 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014 RIP: 0010:remove_proc_entry+0x1bb/0x2d0 fs/proc/generic.c:711 Code: 41 5d 41 5e c3 e8 85 09 b5 ff 48 c7 c7 88 58 64 86 e8 09 0e 71 02 e8 74 09 b5 ff 4c 89 e6 48 c7 c7 de 1b 80 84 e8 c5 ad 97 ff <0f> 0b eb b1 e8 5c 09 b5 ff 48 c7 c7 88 58 64 86 e8 e0 0d 71 02 eb RSP: 0018:ffffc9000c6d7ce0 EFLAGS: 00010286 RAX: 0000000000000000 RBX: ffff8880422b8b00 RCX: ffffffff8110503c RDX: ffff888030652f00 RSI: ffffffff81105045 RDI: 0000000000000001 RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000001 R11: ffffffff81bb62cb R12: ffffffff84807ffc R13: ffff88804ad6fcc0 R14: ffffffff84807ffc R15: ffffffff85741ff8 FS: 00007f30cfba8640(0000) GS:ffff88807dd00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ff51afe8000 CR3: 000000005a60a005 CR4: 0000000000770ef0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 PKRU: 55555554 Call Trace: rpc_proc_unregister+0x64/0x70 net/sunrpc/stats.c:310 nfs_net_exit+0x1c/0x30 fs/nfs/inode.c:2438 ops_exit_list+0x62/0xb0 net/core/net_namespace.c:170 setup_net+0x46c/0x660 net/core/net_namespace.c:372 copy_net_ns+0x244/0x590 net/core/net_namespace.c:505 create_new_namespaces+0x2ed/0x770 kernel/nsproxy.c:110 unshare_nsproxy_namespaces+0xae/0x160 kernel/nsproxy.c:228 ksys_unshare+0x342/0x760 kernel/fork.c:3322 __do_sys_unshare kernel/fork.c:3393 [inline] __se_sys_unshare kernel/fork.c:3391 [inline] __x64_sys_unshare+0x1f/0x30 kernel/fork.c:3391 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0x4f/0x110 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x46/0x4e RIP: 0033:0x7f30d0febe5d Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 73 9f 1b 00 f7 d8 64 89 01 48 RSP: 002b:00007f30cfba7cc8 EFLAGS: 00000246 ORIG_RAX: 0000000000000110 RAX: ffffffffffffffda RBX: 00000000004bbf80 RCX: 00007f30d0febe5d RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000000006c020600 RBP: 00000000004bbf80 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000002 R13: 000000000000000b R14: 00007f30d104c530 R15: 0000000000000000 Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reported-by: syzkaller Signed-off-by: Kuniyuki Iwashima Signed-off-by: Trond Myklebust --- fs/nfs/inode.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c index 91b4d811958a..6fe4b47c3928 100644 --- a/fs/nfs/inode.c +++ b/fs/nfs/inode.c @@ -2429,7 +2429,12 @@ static int nfs_net_init(struct net *net) struct nfs_net *nn = net_generic(net, nfs_net_id); nfs_clients_init(net); - rpc_proc_register(net, &nn->rpcstats); + + if (!rpc_proc_register(net, &nn->rpcstats)) { + nfs_clients_exit(net); + return -ENOMEM; + } + return nfs_fs_proc_net_init(net); }