user/sven/linux.git/include/linux/sunrpc, branch v4.20.13

sunrpc: use-after-free in svc_process_common()

2019-01-16T21:03:26Z

commit d4b09acf924b84bae77cad090a9d108e70b43643 upstream. if node have NFSv41+ mounts inside several net namespaces it can lead to use-after-free in svc_process_common() svc_process_common() /* Setup reply header */ rqstp->rq_xprt->xpt_ops->xpo_prep_reply_hdr(rqstp); <<< HERE svc_process_common() can use incorrect rqstp->rq_xprt, its caller function bc_svc_process() takes it from serv->sv_bc_xprt. The problem is that serv is global structure but sv_bc_xprt is assigned per-netnamespace. According to Trond, the whole "let's set up rqstp->rq_xprt for the back channel" is nothing but a giant hack in order to work around the fact that svc_process_common() uses it to find the xpt_ops, and perform a couple of (meaningless for the back channel) tests of xpt_flags. All we really need in svc_process_common() is to be able to run rqstp->rq_xprt->xpt_ops->xpo_prep_reply_hdr() Bruce J Fields points that this xpo_prep_reply_hdr() call is an awfully roundabout way just to do "svc_putnl(resv, 0);" in the tcp case. This patch does not initialiuze rqstp->rq_xprt in bc_svc_process(), now it calls svc_process_common() with rqstp->rq_xprt = NULL. To adjust reply header svc_process_common() just check rqstp->rq_prot and calls svc_tcp_prep_reply_hdr() for tcp case. To handle rqstp->rq_xprt = NULL case in functions called from svc_process_common() patch intruduces net namespace pointer svc_rqst->rq_bc_net and adjust SVC_NET() definition. Some other function was also adopted to properly handle described case. Signed-off-by: Vasily Averin Cc: stable@vger.kernel.org Fixes: 23c20ecd4475 ("NFS: callback up - users counting cleanup") Signed-off-by: J. Bruce Fields v2: added lost extern svc_tcp_prep_reply_hdr() Signed-off-by: Vasily Averin Signed-off-by: Greg Kroah-Hartman

SUNRPC: Fix a memory leak in call_encode()

2018-12-02T14:43:57Z

If we retransmit an RPC request, we currently end up clobbering the value of req->rq_rcv_buf.bvec that was allocated by the initial call to xprt_request_prepare(req). Signed-off-by: Trond Myklebust

Merge tag 'nfs-for-4.20-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs

2018-11-04T16:20:09Z

Pull NFS client bugfixes from Trond Myklebust: "Highlights include: Bugfix: - Fix build issues on architectures that don't provide 64-bit cmpxchg Cleanups: - Fix a spelling mistake" * tag 'nfs-for-4.20-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: NFS: fix spelling mistake, EACCESS -> EACCES SUNRPC: Use atomic(64)_t for seq_send(64)

SUNRPC: Use atomic(64)_t for seq_send(64)

2018-11-01T17:55:24Z

The seq_send & seq_send64 fields in struct krb5_ctx are used as atomically incrementing counters. This is implemented using cmpxchg() & cmpxchg64() to implement what amount to custom versions of atomic_fetch_inc() & atomic64_fetch_inc(). Besides the duplication, using cmpxchg64() has another major drawback in that some 32 bit architectures don't provide it. As such commit 571ed1fd2390 ("SUNRPC: Replace krb5_seq_lock with a lockless scheme") resulted in build failures for some architectures. Change seq_send to be an atomic_t and seq_send64 to be an atomic64_t, then use atomic(64)_* functions to manipulate the values. The atomic64_t type & associated functions are provided even on architectures which lack real 64 bit atomic memory access via CONFIG_GENERIC_ATOMIC64 which uses spinlocks to serialize access. This fixes the build failures for architectures lacking cmpxchg64(). A potential alternative that was raised would be to provide cmpxchg64() on the 32 bit architectures that currently lack it, using spinlocks. However this would provide a version of cmpxchg64() with semantics a little different to the implementations on architectures with real 64 bit atomics - the spinlock-based implementation would only work if all access to the memory used with cmpxchg64() is *always* performed using cmpxchg64(). That is not currently a requirement for users of cmpxchg64(), and making it one seems questionable. As such avoiding cmpxchg64() outside of architecture-specific code seems best, particularly in cases where atomic64_t seems like a better fit anyway. The CONFIG_GENERIC_ATOMIC64 implementation of atomic64_* functions will use spinlocks & so faces the same issue, but with the key difference that the memory backing an atomic64_t ought to always be accessed via the atomic64_* functions anyway making the issue moot. Signed-off-by: Paul Burton Fixes: 571ed1fd2390 ("SUNRPC: Replace krb5_seq_lock with a lockless scheme") Cc: Trond Myklebust Cc: Anna Schumaker Cc: J. Bruce Fields Cc: Jeff Layton Cc: David S. Miller Cc: linux-nfs@vger.kernel.org Cc: netdev@vger.kernel.org Signed-off-by: Trond Myklebust

Merge tag 'nfsd-4.20' of git://linux-nfs.org/~bfields/linux

2018-10-30T20:03:29Z

Pull nfsd updates from Bruce Fields: "Olga added support for the NFSv4.2 asynchronous copy protocol. We already supported COPY, by copying a limited amount of data and then returning a short result, letting the client resend. The asynchronous protocol should offer better performance at the expense of some complexity. The other highlight is Trond's work to convert the duplicate reply cache to a red-black tree, and to move it and some other server caches to RCU. (Previously these have meant taking global spinlocks on every RPC) Otherwise, some RDMA work and miscellaneous bugfixes" * tag 'nfsd-4.20' of git://linux-nfs.org/~bfields/linux: (30 commits) lockd: fix access beyond unterminated strings in prints nfsd: Fix an Oops in free_session() nfsd: correctly decrement odstate refcount in error path svcrdma: Increase the default connection credit limit svcrdma: Remove try_module_get from backchannel svcrdma: Remove ->release_rqst call in bc reply handler svcrdma: Reduce max_send_sges nfsd: fix fall-through annotations knfsd: Improve lookup performance in the duplicate reply cache using an rbtree knfsd: Further simplify the cache lookup knfsd: Simplify NFS duplicate replay cache knfsd: Remove dead code from nfsd_cache_lookup SUNRPC: Simplify TCP receive code SUNRPC: Replace the cache_detail->hash_lock with a regular spinlock SUNRPC: Remove non-RCU protected lookup NFS: Fix up a typo in nfs_dns_ent_put NFS: Lockless DNS lookups knfsd: Lockless lookup of NFSv4 identities. SUNRPC: Lockless server RPCSEC_GSS context lookup knfsd: Allow lockless lookups of the exports ...

svcrdma: Increase the default connection credit limit

2018-10-29T20:58:04Z

Reduce queuing on clients by allowing more credits by default. 64 is the default NFSv4.1 slot table size on Linux clients. This size prevents the credit limit from putting RPC requests to sleep again after they have already slept waiting for a session slot. Signed-off-by: Chuck Lever Reviewed-by: Sagi Grimberg Signed-off-by: J. Bruce Fields

SUNRPC: Replace the cache_detail->hash_lock with a regular spinlock

2018-10-29T20:58:04Z

Now that the reader functions are all RCU protected, use a regular spinlock rather than a reader/writer lock. Signed-off-by: Trond Myklebust Signed-off-by: J. Bruce Fields

SUNRPC: Remove non-RCU protected lookup

2018-10-29T20:58:04Z

Clean up the cache code by removing the non-RCU protected lookup. Signed-off-by: Trond Myklebust Signed-off-by: J. Bruce Fields

SUNRPC: Allow cache lookups to use RCU protection rather than the r/w spinlock

2018-10-29T20:57:59Z

Instead of the reader/writer spinlock, allow cache lookups to use RCU for looking up entries. This is more efficient since modifications can occur while other entries are being looked up. Note that for now, we keep the reader/writer spinlock until all users have been converted to use RCU-safe freeing of their cache entries. Signed-off-by: Trond Myklebust Signed-off-by: J. Bruce Fields

Merge tag 'nfs-for-4.20-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs

2018-10-26T20:05:26Z

Pull NFS client updates from Trond Myklebust: "Highlights include: Stable fixes: - Fix the NFSv4.1 r/wsize sanity checking - Reset the RPC/RDMA credit grant properly after a disconnect - Fix a missed page unlock after pg_doio() Features and optimisations: - Overhaul of the RPC client socket code to eliminate a locking bottleneck and reduce the latency when transmitting lots of requests in parallel. - Allow parallelisation of the RPCSEC_GSS encoding of an RPC request. - Convert the RPC client socket receive code to use iovec_iter() for improved efficiency. - Convert several NFS and RPC lookup operations to use RCU instead of taking global locks. - Avoid the need for BH-safe locks in the RPC/RDMA back channel. Bugfixes and cleanups: - Fix lock recovery during NFSv4 delegation recalls - Fix the NFSv4 + NFSv4.1 "lookup revalidate + open file" case. - Fixes for the RPC connection metrics - Various RPC client layer cleanups to consolidate stream based sockets - RPC/RDMA connection cleanups - Simplify the RPC/RDMA cleanup after memory operation failures - Clean ups for NFS v4.2 copy completion and NFSv4 open state reclaim" * tag 'nfs-for-4.20-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (97 commits) SUNRPC: Convert the auth cred cache to use refcount_t SUNRPC: Convert auth creds to use refcount_t SUNRPC: Simplify lookup code SUNRPC: Clean up the AUTH cache code NFS: change sign of nfs_fh length sunrpc: safely reallow resvport min/max inversion nfs: remove redundant call to nfs_context_set_write_error() nfs: Fix a missed page unlock after pg_doio() SUNRPC: Fix a compile warning for cmpxchg64() NFSv4.x: fix lock recovery during delegation recall SUNRPC: use cmpxchg64() in gss_seq_send64_fetch_and_inc() xprtrdma: Squelch a sparse warning xprtrdma: Clean up xprt_rdma_disconnect_inject xprtrdma: Add documenting comments xprtrdma: Report when there were zero posted Receives xprtrdma: Move rb_flags initialization xprtrdma: Don't disable BH's in backchannel server xprtrdma: Remove memory address of "ep" from an error message xprtrdma: Rename rpcrdma_qp_async_error_upcall xprtrdma: Simplify RPC wake-ups on connect ...