kernel.git/fs/nfsd, branch linux-6.10.y

NFSD: Limit the number of concurrent async COPY operations

2024-10-10T10:01:11Z

[ Upstream commit aadc3bbea163b6caaaebfdd2b6c4667fbc726752 ] Nothing appears to limit the number of concurrent async COPY operations that clients can start. In addition, AFAICT each async COPY can copy an unlimited number of 4MB chunks, so can run for a long time. Thus IMO async COPY can become a DoS vector. Add a restriction mechanism that bounds the number of concurrent background COPY operations. Start simple and try to be fair -- this patch implements a per-namespace limit. An async COPY request that occurs while this limit is exceeded gets NFS4ERR_DELAY. The requesting client can choose to send the request again after a delay or fall back to a traditional read/write style copy. If there is need to make the mechanism more sophisticated, we can visit that in future patches. Cc: stable@vger.kernel.org Reviewed-by: Jeff Layton Signed-off-by: Chuck Lever Signed-off-by: Sasha Levin

NFSD: Async COPY result needs to return a write verifier

2024-10-10T10:01:10Z

[ Upstream commit 9ed666eba4e0a2bb8ffaa3739d830b64d4f2aaad ] Currently, when NFSD handles an asynchronous COPY, it returns a zero write verifier, relying on the subsequent CB_OFFLOAD callback to pass the write verifier and a stable_how4 value to the client. However, if the CB_OFFLOAD never arrives at the client (for example, if a network partition occurs just as the server sends the CB_OFFLOAD operation), the client will never receive this verifier. Thus, if the client sends a follow-up COMMIT, there is no way for the client to assess the COMMIT result. The usual recovery for a missing CB_OFFLOAD is for the client to send an OFFLOAD_STATUS operation, but that operation does not carry a write verifier in its result. Neither does it carry a stable_how4 value, so the client /must/ send a COMMIT in this case -- which will always fail because currently there's still no write verifier in the COPY result. Thus the server needs to return a normal write verifier in its COPY result even if the COPY operation is to be performed asynchronously. If the server recognizes the callback stateid in subsequent OFFLOAD_STATUS operations, then obviously it has not restarted, and the write verifier the client received in the COPY result is still valid and can be used to assess a COMMIT of the copied data, if one is needed. Reviewed-by: Jeff Layton Signed-off-by: Chuck Lever Stable-dep-of: aadc3bbea163 ("NFSD: Limit the number of concurrent async COPY operations") Signed-off-by: Sasha Levin

sunrpc: change sp_nrthreads from atomic_t to unsigned int.

2024-10-10T10:01:10Z

[ Upstream commit 60749cbe3d8ae572a6c7dda675de3e8b25797a18 ] sp_nrthreads is only ever accessed under the service mutex nlmsvc_mutex nfs_callback_mutex nfsd_mutex so these is no need for it to be an atomic_t. The fact that all code using it is single-threaded means that we can simplify svc_pool_victim and remove the temporary elevation of sp_nrthreads. Signed-off-by: NeilBrown Signed-off-by: Chuck Lever Stable-dep-of: aadc3bbea163 ("NFSD: Limit the number of concurrent async COPY operations") Signed-off-by: Sasha Levin

NFSD: Fix NFSv4's PUTPUBFH operation

2024-10-10T10:00:58Z

commit 202f39039a11402dcbcd5fece8d9fa6be83f49ae upstream. According to RFC 8881, all minor versions of NFSv4 support PUTPUBFH. Replace the XDR decoder for PUTPUBFH with a "noop" since we no longer want the minorversion check, and PUTPUBFH has no arguments to decode. (Ideally nfsd4_decode_noop should really be called nfsd4_decode_void). PUTPUBFH should now behave just like PUTROOTFH. Reported-by: Cedric Blancher Fixes: e1a90ebd8b23 ("NFSD: Combine decode operations for v4 and v4.1") Cc: Dan Shelton Cc: Roland Mainz Cc: stable@vger.kernel.org Signed-off-by: Chuck Lever Signed-off-by: Greg Kroah-Hartman

nfsd: map the EBADMSG to nfserr_io to avoid warning

2024-10-10T10:00:58Z

commit 340e61e44c1d2a15c42ec72ade9195ad525fd048 upstream. Ext4 will throw -EBADMSG through ext4_readdir when a checksum error occurs, resulting in the following WARNING. Fix it by mapping EBADMSG to nfserr_io. nfsd_buffered_readdir iterate_dir // -EBADMSG -74 ext4_readdir // .iterate_shared ext4_dx_readdir ext4_htree_fill_tree htree_dirblock_to_tree ext4_read_dirblock __ext4_read_dirblock ext4_dirblock_csum_verify warn_no_space_for_csum __warn_no_space_for_csum return ERR_PTR(-EFSBADCRC) // -EBADMSG -74 nfserrno // WARNING [ 161.115610] ------------[ cut here ]------------ [ 161.116465] nfsd: non-standard errno: -74 [ 161.117315] WARNING: CPU: 1 PID: 780 at fs/nfsd/nfsproc.c:878 nfserrno+0x9d/0xd0 [ 161.118596] Modules linked in: [ 161.119243] CPU: 1 PID: 780 Comm: nfsd Not tainted 5.10.0-00014-g79679361fd5d #138 [ 161.120684] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qe mu.org 04/01/2014 [ 161.123601] RIP: 0010:nfserrno+0x9d/0xd0 [ 161.124676] Code: 0f 87 da 30 dd 00 83 e3 01 b8 00 00 00 05 75 d7 44 89 ee 48 c7 c7 c0 57 24 98 89 44 24 04 c6 05 ce 2b 61 03 01 e8 99 20 d8 00 <0f> 0b 8b 44 24 04 eb b5 4c 89 e6 48 c7 c7 a0 6d a4 99 e8 cc 15 33 [ 161.127797] RSP: 0018:ffffc90000e2f9c0 EFLAGS: 00010286 [ 161.128794] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 [ 161.130089] RDX: 1ffff1103ee16f6d RSI: 0000000000000008 RDI: fffff520001c5f2a [ 161.131379] RBP: 0000000000000022 R08: 0000000000000001 R09: ffff8881f70c1827 [ 161.132664] R10: ffffed103ee18304 R11: 0000000000000001 R12: 0000000000000021 [ 161.133949] R13: 00000000ffffffb6 R14: ffff8881317c0000 R15: ffffc90000e2fbd8 [ 161.135244] FS: 0000000000000000(0000) GS:ffff8881f7080000(0000) knlGS:0000000000000000 [ 161.136695] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 161.137761] CR2: 00007fcaad70b348 CR3: 0000000144256006 CR4: 0000000000770ee0 [ 161.139041] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 161.140291] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 161.141519] PKRU: 55555554 [ 161.142076] Call Trace: [ 161.142575] ? __warn+0x9b/0x140 [ 161.143229] ? nfserrno+0x9d/0xd0 [ 161.143872] ? report_bug+0x125/0x150 [ 161.144595] ? handle_bug+0x41/0x90 [ 161.145284] ? exc_invalid_op+0x14/0x70 [ 161.146009] ? asm_exc_invalid_op+0x12/0x20 [ 161.146816] ? nfserrno+0x9d/0xd0 [ 161.147487] nfsd_buffered_readdir+0x28b/0x2b0 [ 161.148333] ? nfsd4_encode_dirent_fattr+0x380/0x380 [ 161.149258] ? nfsd_buffered_filldir+0xf0/0xf0 [ 161.150093] ? wait_for_concurrent_writes+0x170/0x170 [ 161.151004] ? generic_file_llseek_size+0x48/0x160 [ 161.151895] nfsd_readdir+0x132/0x190 [ 161.152606] ? nfsd4_encode_dirent_fattr+0x380/0x380 [ 161.153516] ? nfsd_unlink+0x380/0x380 [ 161.154256] ? override_creds+0x45/0x60 [ 161.155006] nfsd4_encode_readdir+0x21a/0x3d0 [ 161.155850] ? nfsd4_encode_readlink+0x210/0x210 [ 161.156731] ? write_bytes_to_xdr_buf+0x97/0xe0 [ 161.157598] ? __write_bytes_to_xdr_buf+0xd0/0xd0 [ 161.158494] ? lock_downgrade+0x90/0x90 [ 161.159232] ? nfs4svc_decode_voidarg+0x10/0x10 [ 161.160092] nfsd4_encode_operation+0x15a/0x440 [ 161.160959] nfsd4_proc_compound+0x718/0xe90 [ 161.161818] nfsd_dispatch+0x18e/0x2c0 [ 161.162586] svc_process_common+0x786/0xc50 [ 161.163403] ? nfsd_svc+0x380/0x380 [ 161.164137] ? svc_printk+0x160/0x160 [ 161.164846] ? svc_xprt_do_enqueue.part.0+0x365/0x380 [ 161.165808] ? nfsd_svc+0x380/0x380 [ 161.166523] ? rcu_is_watching+0x23/0x40 [ 161.167309] svc_process+0x1a5/0x200 [ 161.168019] nfsd+0x1f5/0x380 [ 161.168663] ? nfsd_shutdown_threads+0x260/0x260 [ 161.169554] kthread+0x1c4/0x210 [ 161.170224] ? kthread_insert_work_sanity_check+0x80/0x80 [ 161.171246] ret_from_fork+0x1f/0x30 Signed-off-by: Li Lingfeng Reviewed-by: Jeff Layton Cc: stable@vger.kernel.org Signed-off-by: Chuck Lever Signed-off-by: Greg Kroah-Hartman

nfsd: fix delegation_blocked() to block correctly for at least 30 seconds

2024-10-10T10:00:57Z

commit 45bb63ed20e02ae146336412889fe5450316a84f upstream. The pair of bloom filtered used by delegation_blocked() was intended to block delegations on given filehandles for between 30 and 60 seconds. A new filehandle would be recorded in the "new" bit set. That would then be switch to the "old" bit set between 0 and 30 seconds later, and it would remain as the "old" bit set for 30 seconds. Unfortunately the code intended to clear the old bit set once it reached 30 seconds old, preparing it to be the next new bit set, instead cleared the *new* bit set before switching it to be the old bit set. This means that the "old" bit set is always empty and delegations are blocked between 0 and 30 seconds. This patch updates bd->new before clearing the set with that index, instead of afterwards. Reported-by: Olga Kornievskaia Cc: stable@vger.kernel.org Fixes: 6282cd565553 ("NFSD: Don't hand out delegations for 30 seconds after recalling them.") Signed-off-by: NeilBrown Reviewed-by: Benjamin Coddington Reviewed-by: Jeff Layton Signed-off-by: Chuck Lever Signed-off-by: Greg Kroah-Hartman

nfsd: fix initial getattr on write delegation

2024-10-04T14:33:14Z

[ Upstream commit bf92e5008b17f935a6de8b708551e02c2294121c ] At this point in compound processing, currentfh refers to the parent of the file, not the file itself. Get the correct dentry from the delegation stateid instead. Fixes: c5967721e106 ("NFSD: handle GETATTR conflict with write delegation") Signed-off-by: Jeff Layton Signed-off-by: Chuck Lever Signed-off-by: Sasha Levin

nfsd: untangle code in nfsd4_deleg_getattr_conflict()

2024-10-04T14:33:13Z

[ Upstream commit a078a7dc0eaa9db288ae45319f7f7503968af546 ] The code in nfsd4_deleg_getattr_conflict() is convoluted and buggy. With this patch we: - properly handle non-nfsd leases. We must not assume flc_owner is a delegation unless fl_lmops == &nfsd_lease_mng_ops - move the main code out of the for loop - have a single exit which calls nfs4_put_stid() (and other exits which don't need to call that) [ jlayton: refactored on top of Neil's other patch: nfsd: fix nfsd4_deleg_getattr_conflict in presence of third party lease ] Fixes: c5967721e106 ("NFSD: handle GETATTR conflict with write delegation") Signed-off-by: NeilBrown Signed-off-by: Jeff Layton Signed-off-by: Chuck Lever Signed-off-by: Sasha Levin

nfsd: return -EINVAL when namelen is 0

2024-10-04T14:33:13Z

[ Upstream commit 22451a16b7ab7debefce660672566be887db1637 ] When we have a corrupted main.sqlite in /var/lib/nfs/nfsdcld/, it may result in namelen being 0, which will cause memdup_user() to return ZERO_SIZE_PTR. When we access the name.data that has been assigned the value of ZERO_SIZE_PTR in nfs4_client_to_reclaim(), null pointer dereference is triggered. [ T1205] ================================================================== [ T1205] BUG: KASAN: null-ptr-deref in nfs4_client_to_reclaim+0xe9/0x260 [ T1205] Read of size 1 at addr 0000000000000010 by task nfsdcld/1205 [ T1205] [ T1205] CPU: 11 PID: 1205 Comm: nfsdcld Not tainted 5.10.0-00003-g2c1423731b8d #406 [ T1205] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ?-20190727_073836-buildvm-ppc64le-16.ppc.fedoraproject.org-3.fc31 04/01/2014 [ T1205] Call Trace: [ T1205] dump_stack+0x9a/0xd0 [ T1205] ? nfs4_client_to_reclaim+0xe9/0x260 [ T1205] __kasan_report.cold+0x34/0x84 [ T1205] ? nfs4_client_to_reclaim+0xe9/0x260 [ T1205] kasan_report+0x3a/0x50 [ T1205] nfs4_client_to_reclaim+0xe9/0x260 [ T1205] ? nfsd4_release_lockowner+0x410/0x410 [ T1205] cld_pipe_downcall+0x5ca/0x760 [ T1205] ? nfsd4_cld_tracking_exit+0x1d0/0x1d0 [ T1205] ? down_write_killable_nested+0x170/0x170 [ T1205] ? avc_policy_seqno+0x28/0x40 [ T1205] ? selinux_file_permission+0x1b4/0x1e0 [ T1205] rpc_pipe_write+0x84/0xb0 [ T1205] vfs_write+0x143/0x520 [ T1205] ksys_write+0xc9/0x170 [ T1205] ? __ia32_sys_read+0x50/0x50 [ T1205] ? ktime_get_coarse_real_ts64+0xfe/0x110 [ T1205] ? ktime_get_coarse_real_ts64+0xa2/0x110 [ T1205] do_syscall_64+0x33/0x40 [ T1205] entry_SYSCALL_64_after_hwframe+0x67/0xd1 [ T1205] RIP: 0033:0x7fdbdb761bc7 [ T1205] Code: 0f 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b7 0f 1f 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 514 [ T1205] RSP: 002b:00007fff8c4b7248 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 [ T1205] RAX: ffffffffffffffda RBX: 000000000000042b RCX: 00007fdbdb761bc7 [ T1205] RDX: 000000000000042b RSI: 00007fff8c4b75f0 RDI: 0000000000000008 [ T1205] RBP: 00007fdbdb761bb0 R08: 0000000000000000 R09: 0000000000000001 [ T1205] R10: 0000000000000000 R11: 0000000000000246 R12: 000000000000042b [ T1205] R13: 0000000000000008 R14: 00007fff8c4b75f0 R15: 0000000000000000 [ T1205] ================================================================== Fix it by checking namelen. Signed-off-by: Li Lingfeng Fixes: 74725959c33c ("nfsd: un-deprecate nfsdcld") Reviewed-by: Jeff Layton Reviewed-by: Scott Mayhew Tested-by: Scott Mayhew Signed-off-by: Chuck Lever Signed-off-by: Sasha Levin

nfsd: call cache_put if xdr_reserve_space returns NULL

2024-10-04T14:33:13Z

[ Upstream commit d078cbf5c38de83bc31f83c47dcd2184c04a50c7 ] If not enough buffer space available, but idmap_lookup has triggered lookup_fn which calls cache_get and returns successfully. Then we missed to call cache_put here which pairs with cache_get. Fixes: ddd1ea563672 ("nfsd4: use xdr_reserve_space in attribute encoding") Signed-off-by: Guoqing Jiang Reviwed-by: Jeff Layton Signed-off-by: Chuck Lever Signed-off-by: Sasha Levin