We currently have a problem that SELinux policy is being enforced when
creating debugfs files. If a debugfs file is created as a side effect of
doing some syscall, then that creation can fail if the SELinux policy
for that process prevents it.
This seems wrong. We don't do that for files under /proc, for instance,
so Bruce has proposed a patch to fix that.
While discussing that patch however, Greg K.H. stated:
"No kernel code should care / fail if a debugfs function fails, so
please fix up the sunrpc code first."
This patch converts all of the sunrpc debugfs setup code to be void
return functins, and the callers to not look for errors from those
functions.
This should allow rpc_clnt and rpc_xprt creation to work, even if the
kernel fails to create debugfs files for some reason.
Symptoms were failing krb5 mounts on systems using gss-proxy and
selinux.
Fixes: 388f0c7767 "sunrpc: add a debugfs rpc_xprt directory..."
Cc: stable@vger.kernel.org
Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Pull NFS client bugfixes from Trond Myklebust:
"Highlights include:
- Fix a regression in the NFSv4 open state recovery code
- Fix a regression in the NFSv4 close code
- Fix regressions and side-effects of the loop-back mounted NFS fixes
in 3.18, that cause the NFS read() syscall to return EBUSY.
- Fix regressions around the readdirplus code and how it interacts
with the VFS lazy unmount changes that went into v3.18.
- Fix issues with out-of-order RPC call replies replacing updated
attributes with stale ones (particularly after a truncate()).
- Fix an underflow checking issue with RPC/RDMA credits
- Fix a number of issues with the NFSv4 delegation return/free code.
- Fix issues around stale NFSv4.1 leases when doing a mount"
* tag 'nfs-for-4.0-3' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (24 commits)
NFSv4.1: Clear the old state by our client id before establishing a new lease
NFSv4: Fix a race in NFSv4.1 server trunking discovery
NFS: Don't write enable new pages while an invalidation is proceeding
NFS: Fix a regression in the read() syscall
NFSv4: Ensure we skip delegations that are already being returned
NFSv4: Pin the superblock while we're returning the delegation
NFSv4: Ensure we honour NFS_DELEGATION_RETURNING in nfs_inode_set_delegation()
NFSv4: Ensure that we don't reap a delegation that is being returned
NFS: Fix stateid used for NFS v4 closes
NFSv4: Don't call put_rpccred() under the rcu_read_lock()
NFS: Don't require a filehandle to refresh the inode in nfs_prime_dcache()
NFSv3: Use the readdir fileid as the mounted-on-fileid
NFS: Don't invalidate a submounted dentry in nfs_prime_dcache()
NFSv4: Set a barrier in the update_changeattr() helper
NFS: Fix nfs_post_op_update_inode() to set an attribute barrier
NFS: Remove size hack in nfs_inode_attrs_need_update()
NFSv4: Add attribute update barriers to delegreturn and pNFS layoutcommit
NFS: Add attribute update barriers to NFS writebacks
NFS: Set an attribute barrier on all updates
NFS: Add attribute update barriers to nfs_setattr_update_inode()
...
Pull nfsd fixes from Bruce Fields:
"Three miscellaneous bugfixes, most importantly the clp->cl_revoked
bug, which we've seen several reports of people hitting"
* 'for-4.0' of git://linux-nfs.org/~bfields/linux:
sunrpc: integer underflow in rsc_parse()
nfsd: fix clp->cl_revoked list deletion causing softlock in nfsd
svcrpc: fix memory leak in gssp_accept_sec_context_upcall
If we call groups_alloc() with invalid values then it's might lead to
memory corruption. For example, with a negative value then we might not
allocate enough for sizeof(struct group_info).
(We're doing this in the caller for consistency with other callers of
groups_alloc(). The other alternative might be to move the check out of
all the callers into groups_alloc().)
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Simo Sorce <simo@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
NFS: RDMA Client Sparse Fix#2
This patch fixes another sparse fix found by Dan Carpenter's tool.
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
* tag 'nfs-rdma-for-4.0-3' of git://git.linux-nfs.org/projects/anna/nfs-rdma:
xprtrdma: Store RDMA credits in unsigned variables
Dan Carpenter's static checker pointed out:
net/sunrpc/xprtrdma/rpc_rdma.c:879 rpcrdma_reply_handler()
warn: can 'credits' be negative?
"credits" is defined as an int. The credits value comes from the
server as a 32-bit unsigned integer.
A malicious or broken server can plant a large unsigned integer in
that field which would result in an underflow in the following
logic, potentially triggering a deadlock of the mount point by
blocking the client from issuing more RPC requests.
net/sunrpc/xprtrdma/rpc_rdma.c:
876 credits = be32_to_cpu(headerp->rm_credit);
877 if (credits == 0)
878 credits = 1; /* don't deadlock */
879 else if (credits > r_xprt->rx_buf.rb_max_requests)
880 credits = r_xprt->rx_buf.rb_max_requests;
881
882 cwnd = xprt->cwnd;
883 xprt->cwnd = credits << RPC_CWNDSHIFT;
884 if (xprt->cwnd > cwnd)
885 xprt_release_rqst_cong(rqst->rq_task);
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Fixes: eba8ff660b ("xprtrdma: Move credit update to RPC . . .")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Merge cleanups requested by Linus.
* cleanups: (3 commits)
pnfs: Refactor the *_layout_mark_request_commit to use pnfs_layout_mark_request_commit
nfs: Can call nfs_clear_page_commit() instead
nfs: Provide and use helper functions for marking a page as unstable
Our UC-KLEE tool found a kernel memory leak of 512 bytes (on x86_64) for
each call to gssp_accept_sec_context_upcall()
(net/sunrpc/auth_gss/gss_rpc_upcall.c). Since it appears that this call
can be triggered by remote connections (at least, from a cursory a
glance at the call chain), it may be exploitable to cause kernel memory
exhaustion. We found the bug in kernel 3.16.3, but it appears to date
back to commit 9dfd87da1a (2013-08-20).
The gssp_accept_sec_context_upcall() function performs a pair of calls
to gssp_alloc_receive_pages() and gssp_free_receive_pages(). The first
allocates memory for arg->pages. The second then frees the pages
pointed to by the arg->pages array, but not the array itself.
Reported-by: David A. Ramos <daramos@stanford.edu>
Fixes: 9dfd87da1a ("rpc: fix huge kmalloc's in gss-proxy”)
Signed-off-by: David A. Ramos <daramos@stanford.edu>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Other code that accesses rq_bc_pa_list holds xprt->bc_pa_lock.
xprt_complete_bc_request() should do the same.
Fixes: 2ea24497a1 ("SUNRPC: RPC callbacks may be split . . .")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Pull nfsd updates from Bruce Fields:
"The main change is the pNFS block server support from Christoph, which
allows an NFS client connected to shared disk to do block IO to the
shared disk in place of NFS reads and writes. This also requires xfs
patches, which should arrive soon through the xfs tree, barring
unexpected problems. Support for other filesystems is also possible
if there's interest.
Thanks also to Chuck Lever for continuing work to get NFS/RDMA into
shape"
* 'for-3.20' of git://linux-nfs.org/~bfields/linux: (32 commits)
nfsd: default NFSv4.2 to on
nfsd: pNFS block layout driver
exportfs: add methods for block layout exports
nfsd: add trace events
nfsd: update documentation for pNFS support
nfsd: implement pNFS layout recalls
nfsd: implement pNFS operations
nfsd: make find_any_file available outside nfs4state.c
nfsd: make find/get/put file available outside nfs4state.c
nfsd: make lookup/alloc/unhash_stid available outside nfs4state.c
nfsd: add fh_fsid_match helper
nfsd: move nfsd_fh_match to nfsfh.h
fs: add FL_LAYOUT lease type
fs: track fl_owner for leases
nfs: add LAYOUT_TYPE_MAX enum value
nfsd: factor out a helper to decode nfstime4 values
sunrpc/lockd: fix references to the BKL
nfsd: fix year-2038 nfs4 state problem
svcrdma: Handle additional inline content
svcrdma: Move read list XDR round-up logic
...
xs_tcp_close() is now just a call to xs_tcp_shutdown(), so remove it,
and replace the entry in xs_tcp_ops.
Suggested-by: Anna Schumaker <anna.schumaker@netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Now that the linger code is gone, the xs_tcp_fin_timeout variable has
no real function. Keep it for now, since it is part of the /proc
interface, but only define it if that /proc interface is enabled.
Suggested-by: Anna Schumaker <Anna.Schumaker@netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
If the connection reset is due to an active call on our side, then
the state change is sometimes not reported. Catch those instances
using xs_error_report() instead.
Also remove the xs_tcp_shutdown() call in xs_tcp_send_request() as
the change in behaviour makes it redundant.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Use of socket shutdown() means that we monitor the shutdown process
through the xs_tcp_state_change() callback, so it is preferable to
a full close in all cases unless we're destroying the transport.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
The previous behaviour left the connection half-open in order to try
to scrape the last replies from the socket. Now that we have more reliable
reconnection, change the behaviour to close down the socket faster.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Now that we no longer use the partial shutdown code when closing the
socket, we no longer need to worry about the TCP linger2 state.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Instead we rely on SO_REUSEPORT to provide the reconnection semantics
that we need for NFSv2/v3.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
It is not safe to call xs_reset_transport() from inside xs_udp_setup_socket()
or xs_tcp_setup_socket(), since they do not own the correct locks. Instead,
do it in xs_connect().
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
The socket lock is currently held by the task that is requesting the
connection be established. While that is efficient in the case where
the connection happens quickly, it is racy in the case where it doesn't.
What we really want is for the connect helper to be able to block access
to the socket while it is being set up.
This patch does so by arranging to transfer the socket lock from the
task that is requesting the connect attempt, and then releasing that
lock once everything is done.
This scheme also gives us automatic protection against collisions with
the RPC close code, so we can kill the cancel_delayed_work_sync()
call in xs_close().
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Now that we can reuse bound ports after a close, we never really want to
clear the transport's source port after it has been set. Doing so really
messes up the NFSv3 DRC on the server.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Jeff Layton
Al Viro
Linus Torvalds
Dan Carpenter
Trond Myklebust
Chuck Lever
David Ramos