linux-dev/fs/nfsd, branch linus/master

Merge tag 'nfsd-5.19-1' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux

2022-06-11T00:28:43Z

Pull nfsd fixes from Chuck Lever: "Notable changes: - There is now a backup maintainer for NFSD Notable fixes: - Prevent array overruns in svc_rdma_build_writes() - Prevent buffer overruns when encoding NFSv3 READDIR results - Fix a potential UAF in nfsd_file_put()" * tag 'nfsd-5.19-1' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux: SUNRPC: Remove pointer type casts from xdr_get_next_encode_buffer() SUNRPC: Clean up xdr_get_next_encode_buffer() SUNRPC: Clean up xdr_commit_encode() SUNRPC: Optimize xdr_reserve_space() SUNRPC: Fix the calculation of xdr->end in xdr_get_next_encode_buffer() SUNRPC: Trap RDMA segment overflows NFSD: Fix potential use-after-free in nfsd_file_put() MAINTAINERS: reciprocal co-maintainership for file locking and nfsd

NFSD: Fix potential use-after-free in nfsd_file_put()

2022-06-02T17:05:58Z

nfsd_file_put_noref() can free @nf, so don't dereference @nf immediately upon return from nfsd_file_put_noref(). Suggested-by: Trond Myklebust Fixes: 999397926ab3 ("nfsd: Clean up nfsd_file_put()") Signed-off-by: Chuck Lever

Merge tag 'nfsd-5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux

2022-05-27T03:52:24Z

Pull nfsd updates from Chuck Lever: "We introduce 'courteous server' in this release. Previously NFSD would purge open and lock state for an unresponsive client after one lease period (typically 90 seconds). Now, after one lease period, another client can open and lock those files and the unresponsive client's lease is purged; otherwise if the unresponsive client's open and lock state is uncontended, the server retains that open and lock state for up to 24 hours, allowing the client's workload to resume after a lengthy network partition. A longstanding issue with NFSv4 file creation is also addressed. Previously a file creation can fail internally, returning an error to the client, but leave the newly created file in place as an artifact. The file creation code path has been reorganized so that internal failures and race conditions are less likely to result in an unwanted file creation. A fault injector has been added to help exercise paths that are run during kernel metadata cache invalidation. These caches contain information maintained by user space about exported filesystems. Many of our test workloads do not trigger cache invalidation. There is one patch that is needed to support PREEMPT_RT and a fix for an ancient 'sleep while spin-locked' splat that seems to have become easier to hit since v5.18-rc3" * tag 'nfsd-5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux: (36 commits) NFSD: nfsd_file_put() can sleep NFSD: Add documenting comment for nfsd4_release_lockowner() NFSD: Modernize nfsd4_release_lockowner() NFSD: Fix possible sleep during nfsd4_release_lockowner() nfsd: destroy percpu stats counters after reply cache shutdown nfsd: Fix null-ptr-deref in nfsd_fill_super() nfsd: Unregister the cld notifier when laundry_wq create failed SUNRPC: Use RMW bitops in single-threaded hot paths NFSD: Clean up the show_nf_flags() macro NFSD: Trace filecache opens NFSD: Move documenting comment for nfsd4_process_open2() NFSD: Fix whitespace NFSD: Remove dprintk call sites from tail of nfsd4_open() NFSD: Instantiate a struct file when creating a regular NFSv4 file NFSD: Clean up nfsd_open_verified() NFSD: Remove do_nfsd_create() NFSD: Refactor NFSv4 OPEN(CREATE) NFSD: Refactor NFSv3 CREATE NFSD: Refactor nfsd_create_setattr() NFSD: Avoid calling fh_drop_write() twice in do_nfsd_create() ...

NFSD: nfsd_file_put() can sleep

2022-05-26T14:50:51Z

Now that there are no more callers of nfsd_file_put() that might hold a spin lock, ensure the lockdep infrastructure can catch newly introduced calls to nfsd_file_put() made while a spinlock is held. Link: https://lore.kernel.org/linux-nfs/ece7fd1d-5fb3-5155-54ba-347cfc19bd9a@oracle.com/T/#mf1855552570cf9a9c80d1e49d91438cd9085aada Signed-off-by: Chuck Lever Reviewed-by: Jeff Layton

NFSD: Add documenting comment for nfsd4_release_lockowner()

2022-05-26T14:50:50Z

And return explicit nfserr values that match what is documented in the new comment / API contract. Signed-off-by: Chuck Lever

NFSD: Modernize nfsd4_release_lockowner()

2022-05-26T14:50:50Z

Refactor: Use existing helpers that other lock operations use. This change removes several automatic variables, so re-organize the variable declarations for readability. Signed-off-by: Chuck Lever

NFSD: Fix possible sleep during nfsd4_release_lockowner()

2022-05-26T14:50:49Z

nfsd4_release_lockowner() holds clp->cl_lock when it calls check_for_locks(). However, check_for_locks() calls nfsd_file_get() / nfsd_file_put() to access the backing inode's flc_posix list, and nfsd_file_put() can sleep if the inode was recently removed. Let's instead rely on the stateowner's reference count to gate whether the release is permitted. This should be a reliable indication of locks-in-use since file lock operations and ->lm_get_owner take appropriate references, which are released appropriately when file locks are removed. Reported-by: Dai Ngo Signed-off-by: Chuck Lever Cc: stable@vger.kernel.org

nfsd: destroy percpu stats counters after reply cache shutdown

2022-05-23T19:22:17Z

Upon nfsd shutdown any pending DRC cache is freed. DRC cache use is tracked via a percpu counter. In the current code the percpu counter is destroyed before. If any pending cache is still present, percpu_counter_add is called with a percpu counter==NULL. This causes a kernel crash. The solution is to destroy the percpu counter after the cache is freed. Fixes: e567b98ce9a4b (“nfsd: protect concurrent access to nfsd stats counters”) Signed-off-by: Julian Schroeder Signed-off-by: Chuck Lever

nfsd: Fix null-ptr-deref in nfsd_fill_super()

2022-05-23T15:06:29Z

KASAN report null-ptr-deref as follows: BUG: KASAN: null-ptr-deref in nfsd_fill_super+0xc6/0xe0 [nfsd] Write of size 8 at addr 000000000000005d by task a.out/852 CPU: 7 PID: 852 Comm: a.out Not tainted 5.18.0-rc7-dirty #66 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-1.fc33 04/01/2014 Call Trace: dump_stack_lvl+0x34/0x44 kasan_report+0xab/0x120 ? nfsd_mkdir+0x71/0x1c0 [nfsd] ? nfsd_fill_super+0xc6/0xe0 [nfsd] nfsd_fill_super+0xc6/0xe0 [nfsd] ? nfsd_mkdir+0x1c0/0x1c0 [nfsd] get_tree_keyed+0x8e/0x100 vfs_get_tree+0x41/0xf0 __do_sys_fsconfig+0x590/0x670 ? fscontext_read+0x180/0x180 ? anon_inode_getfd+0x4f/0x70 do_syscall_64+0x35/0x80 entry_SYSCALL_64_after_hwframe+0x44/0xae This can be reproduce by concurrent operations: 1. fsopen(nfsd)/fsconfig 2. insmod/rmmod nfsd Since the nfsd file system is registered before than nfsd_net allocated, the caller may get the file_system_type and use the nfsd_net before it allocated, then null-ptr-deref occurred. So init_nfsd() should call register_filesystem() last. Fixes: bd5ae9288d64 ("nfsd: register pernet ops last, unregister first") Signed-off-by: Zhang Xiaoxu Signed-off-by: Chuck Lever

nfsd: Unregister the cld notifier when laundry_wq create failed

2022-05-23T15:06:29Z

If laundry_wq create failed, the cld notifier should be unregistered. Signed-off-by: Zhang Xiaoxu Signed-off-by: Chuck Lever