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commit 9c2ece6ef67e9d376f32823086169b489c422ed0 upstream.
nfsd4_readdir_rsize restricts rd_maxcount to svc_max_payload when
estimating the size of the readdir reply, but nfsd_encode_readdir
restricts it to INT_MAX when encoding the reply. This can result in log
messages like "kernel: RPC request reserved 32896 but used 1049444".
Restrict rd_dircount similarly (no reason it should be larger than
svc_max_payload).
Signed-off-by: Scott Mayhew <smayhew@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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commit fc788f64f1f3eb31e87d4f53bcf1ab76590d5838 upstream.
When processing an NFSv4 WRITE operation, argp->end should never
point past the end of the data in the final page of the page list.
Otherwise, nfsd4_decode_compound can walk into uninitialized memory.
More critical, nfsd4_decode_write is failing to increment argp->pagelen
when it increments argp->pagelist. This can cause later xdr decoders
to assume more data is available than really is, which can cause server
crashes on malformed requests.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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commit 4aed9c46afb80164401143aa0fdcfe3798baa9d5 upstream.
A number of spots in the xdr decoding follow a pattern like
n = be32_to_cpup(p++);
READ_BUF(n + 4);
where n is a u32. The only bounds checking is done in READ_BUF itself,
but since it's checking (n + 4), it won't catch cases where n is very
large, (u32)(-4) or higher. I'm not sure exactly what the consequences
are, but we've seen crashes soon after.
Instead, just break these up into two READ_BUF()s.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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commit c2227a39a078473115910512aa0f8d53bd915e60 upstream.
On an absent filesystem (one served by another server), we need to be
able to handle requests for certain attributest (like fs_locations, so
the client can find out which server does have the filesystem), but
others we can't.
We forgot to take that into account when adding another attribute
bitmask work for the SECURITY_LABEL attribute.
There an export entry with the "refer" option can result in:
[ 88.414272] kernel BUG at fs/nfsd/nfs4xdr.c:2249!
[ 88.414828] invalid opcode: 0000 [#1] SMP
[ 88.415368] Modules linked in: rpcsec_gss_krb5 nfsv4 dns_resolver nfs fscache nfsd xfs libcrc32c iscsi_tcp libiscsi_tcp libiscsi scsi_transport_iscsi iosf_mbi ppdev btrfs coretemp crct10dif_pclmul crc32_pclmul crc32c_intel xor ghash_clmulni_intel raid6_pq vmw_balloon parport_pc parport i2c_piix4 shpchp vmw_vmci acpi_cpufreq auth_rpcgss nfs_acl lockd grace sunrpc vmwgfx drm_kms_helper ttm drm mptspi mptscsih serio_raw mptbase e1000 scsi_transport_spi ata_generic pata_acpi [last unloaded: nfsd]
[ 88.417827] CPU: 0 PID: 2116 Comm: nfsd Not tainted 4.0.7-300.fc22.x86_64 #1
[ 88.418448] Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 05/20/2014
[ 88.419093] task: ffff880079146d50 ti: ffff8800785d8000 task.ti: ffff8800785d8000
[ 88.419729] RIP: 0010:[<ffffffffa04b3c10>] [<ffffffffa04b3c10>] nfsd4_encode_fattr+0x820/0x1f00 [nfsd]
[ 88.420376] RSP: 0000:ffff8800785db998 EFLAGS: 00010206
[ 88.421027] RAX: 0000000000000001 RBX: 000000000018091a RCX: ffff88006668b980
[ 88.421676] RDX: 00000000fffef7fc RSI: 0000000000000000 RDI: ffff880078d05000
[ 88.422315] RBP: ffff8800785dbb58 R08: ffff880078d043f8 R09: ffff880078d4a000
[ 88.422968] R10: 0000000000010000 R11: 0000000000000002 R12: 0000000000b0a23a
[ 88.423612] R13: ffff880078d05000 R14: ffff880078683100 R15: ffff88006668b980
[ 88.424295] FS: 0000000000000000(0000) GS:ffff88007c600000(0000) knlGS:0000000000000000
[ 88.424944] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 88.425597] CR2: 00007f40bc370f90 CR3: 0000000035af5000 CR4: 00000000001407f0
[ 88.426285] Stack:
[ 88.426921] ffff8800785dbaa8 ffffffffa049e4af ffff8800785dba08 ffffffff813298f0
[ 88.427585] ffff880078683300 ffff8800769b0de8 0000089d00000001 0000000087f805e0
[ 88.428228] ffff880000000000 ffff880079434a00 0000000000000000 ffff88006668b980
[ 88.428877] Call Trace:
[ 88.429527] [<ffffffffa049e4af>] ? exp_get_by_name+0x7f/0xb0 [nfsd]
[ 88.430168] [<ffffffff813298f0>] ? inode_doinit_with_dentry+0x210/0x6a0
[ 88.430807] [<ffffffff8123833e>] ? d_lookup+0x2e/0x60
[ 88.431449] [<ffffffff81236133>] ? dput+0x33/0x230
[ 88.432097] [<ffffffff8123f214>] ? mntput+0x24/0x40
[ 88.432719] [<ffffffff812272b2>] ? path_put+0x22/0x30
[ 88.433340] [<ffffffffa049ac87>] ? nfsd_cross_mnt+0xb7/0x1c0 [nfsd]
[ 88.433954] [<ffffffffa04b54e0>] nfsd4_encode_dirent+0x1b0/0x3d0 [nfsd]
[ 88.434601] [<ffffffffa04b5330>] ? nfsd4_encode_getattr+0x40/0x40 [nfsd]
[ 88.435172] [<ffffffffa049c991>] nfsd_readdir+0x1c1/0x2a0 [nfsd]
[ 88.435710] [<ffffffffa049a530>] ? nfsd_direct_splice_actor+0x20/0x20 [nfsd]
[ 88.436447] [<ffffffffa04abf30>] nfsd4_encode_readdir+0x120/0x220 [nfsd]
[ 88.437011] [<ffffffffa04b58cd>] nfsd4_encode_operation+0x7d/0x190 [nfsd]
[ 88.437566] [<ffffffffa04aa6dd>] nfsd4_proc_compound+0x24d/0x6f0 [nfsd]
[ 88.438157] [<ffffffffa0496103>] nfsd_dispatch+0xc3/0x220 [nfsd]
[ 88.438680] [<ffffffffa006f0cb>] svc_process_common+0x43b/0x690 [sunrpc]
[ 88.439192] [<ffffffffa0070493>] svc_process+0x103/0x1b0 [sunrpc]
[ 88.439694] [<ffffffffa0495a57>] nfsd+0x117/0x190 [nfsd]
[ 88.440194] [<ffffffffa0495940>] ? nfsd_destroy+0x90/0x90 [nfsd]
[ 88.440697] [<ffffffff810bb728>] kthread+0xd8/0xf0
[ 88.441260] [<ffffffff810bb650>] ? kthread_worker_fn+0x180/0x180
[ 88.441762] [<ffffffff81789e58>] ret_from_fork+0x58/0x90
[ 88.442322] [<ffffffff810bb650>] ? kthread_worker_fn+0x180/0x180
[ 88.442879] Code: 0f 84 93 05 00 00 83 f8 ea c7 85 a0 fe ff ff 00 00 27 30 0f 84 ba fe ff ff 85 c0 0f 85 a5 fe ff ff e9 e3 f9 ff ff 0f 1f 44 00 00 <0f> 0b 66 0f 1f 44 00 00 be 04 00 00 00 4c 89 ef 4c 89 8d 68 fe
[ 88.444052] RIP [<ffffffffa04b3c10>] nfsd4_encode_fattr+0x820/0x1f00 [nfsd]
[ 88.444658] RSP <ffff8800785db998>
[ 88.445232] ---[ end trace 6cb9d0487d94a29f ]---
Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
[ luis: backported to 3.16: adjusted context ]
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
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commit bf7491f1be5e125eece2ec67e0f79d513caa6c7e upstream.
Fix a bug where nfsd4_encode_components_esc() incorrectly calculates the
length of server array in fs_location4--note that it is a count of the
number of array elements, not a length in bytes.
Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Fixes: 082d4bd72a45 (nfsd4: "backfill" using write_bytes_to_xdr_buf)
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
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commit 5a64e56976f1ba98743e1678c0029a98e9034c81 upstream.
Fix a bug where nfsd4_encode_components_esc() includes the esc_end char as
an additional string encoding.
Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Fixes: e7a0444aef4a "nfsd: add IPv6 addr escaping to fs_location hosts"
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
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commit f7b43d0c992c3ec3e8d9285c3fb5e1e0eb0d031a upstream.
As of 8c7424cff6 "nfsd4: don't try to encode conflicting owner if low
on space", we permit the server to process a LOCK operation even if
there might not be space to return the conflicting lockowner, because
we've made returning the conflicting lockowner optional.
However, the rpc server still wants to know the most we might possibly
return, so we need to take into account the possible conflicting
lockowner in the svc_reserve_space() call here.
Symptoms were log messages like "RPC request reserved 88 but used 108".
Fixes: 8c7424cff6 "nfsd4: don't try to encode conflicting owner if low on space"
Reported-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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commit 15b23ef5d348ea51c5e7573e2ef4116fbc7cb099 upstream.
The calculation of page_ptr here is wrong in the case the read doesn't
start at an offset that is a multiple of a page.
The result is that nfs4svc_encode_compoundres sets rq_next_page to a
value one too small, and then the loop in svc_free_res_pages may
incorrectly fail to clear a page pointer in rq_respages[].
Pages left in rq_respages[] are available for the next rpc request to
use, so xdr data may be written to that page, which may hold data still
waiting to be transmitted to the client or data in the page cache.
The observed result was silent data corruption seen on an NFSv4 client.
We tag this as "fixing" 05638dc73af2 because that commit exposed this
bug, though the incorrect calculation predates it.
Particular thanks to Andrea Arcangeli and David Gilbert for analysis and
testing.
Fixes: 05638dc73af2 "nfsd4: simplify server xdr->next_page use"
Reported-by: Andrea Arcangeli <aarcange@redhat.com>
Tested-by: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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commit aee3776441461c14ba6d8ed9e2149933e65abb6e upstream.
Commit 3b299709091b "nfsd4: enforce rd_dircount" totally misunderstood
rd_dircount; it refers to total non-attribute bytes returned, not number
of directory entries returned.
Bring the code into agreement with RFC 3530 section 14.2.24.
Fixes: 3b299709091b "nfsd4: enforce rd_dircount"
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Commit 8c7424cff6 "nfsd4: don't try to encode conflicting owner if low
on space" forgot to free conf->data in nfsd4_encode_lockt and before
sign conf->data to NULL in nfsd4_encode_lock_denied, causing a leak.
Worse, kfree() can be called on an uninitialized pointer in the case of
a succesful lock (or one that fails for a reason other than a conflict).
(Note that lock->lk_denied.ld_owner.data appears it should be zero here,
until you notice that it's one arm of a union the other arm of which is
written to in the succesful case by the
memcpy(&lock->lk_resp_stateid, &lock_stp->st_stid.sc_stateid,
sizeof(stateid_t));
in nfsd4_lock(). In the 32-bit case this overwrites ld_owner.data.)
Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Fixes: 8c7424cff6 ""nfsd4: don't try to encode conflicting owner if low on space"
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
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Introduced by commit 561f0ed498 (nfsd4: allow large readdirs).
Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
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XDR requires 4-byte alignment; nfs4d READLINK reply writes out the padding,
but truncates the packet to the padding-less size.
Fix by taking the padding into consideration when truncating the packet.
Symptoms:
# ll /mnt/
ls: cannot read symbolic link /mnt/test: Input/output error
total 4
-rw-r--r--. 1 root root 0 Jun 14 01:21 123456
lrwxrwxrwx. 1 root root 6 Jul 2 03:33 test
drwxr-xr-x. 1 root root 0 Jul 2 23:50 tmp
drwxr-xr-x. 1 root root 60 Jul 2 23:44 tree
Signed-off-by: Avi Kivity <avi@cloudius-systems.com>
Fixes: 476a7b1f4b2c (nfsd4: don't treat readlink like a zero-copy operation)
Reviewed-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
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An NFS operation that creates a new symlink includes the symlink data,
which is xdr-encoded as a length followed by the data plus 0 to 3 bytes
of zero-padding as required to reach a 4-byte boundary.
The vfs, on the other hand, wants null-terminated data.
The simple way to handle this would be by copying the data into a newly
allocated buffer with space for the final null.
The current nfsd_symlink code tries to be more clever by skipping that
step in the (likely) case where the byte following the string is already
0.
But that assumes that the byte following the string is ours to look at.
In fact, it might be the first byte of a page that we can't read, or of
some object that another task might modify.
Worse, the NFSv4 code tries to fix the problem by actually writing to
that byte.
In the NFSv2/v3 cases this actually appears to be safe:
- nfs3svc_decode_symlinkargs explicitly null-terminates the data
(after first checking its length and copying it to a new
page).
- NFSv2 limits symlinks to 1k. The buffer holding the rpc
request is always at least a page, and the link data (and
previous fields) have maximum lengths that prevent the request
from reaching the end of a page.
In the NFSv4 case the CREATE op is potentially just one part of a long
compound so can end up on the end of a page if you're unlucky.
The minimal fix here is to copy and null-terminate in the NFSv4 case.
The nfsd_symlink() interface here seems too fragile, though. It should
really either do the copy itself every time or just require a
null-terminated string.
Reported-by: Jeff Layton <jlayton@primarydata.com>
Cc: stable@vger.kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
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Commit 561f0ed498ca (nfsd4: allow large readdirs) introduces a bug
about readdir the root of pseudofs.
Call xdr_truncate_encode() revert encoded name when skipping.
Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
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Signed-off-by: J. Bruce Fields <bfields@redhat.com>
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While we're here, let's kill off a couple of the read-side macros.
Leaving the more complicated ones alone for now.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
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sparse says:
CHECK fs/nfsd/nfs4xdr.c
fs/nfsd/nfs4xdr.c:2043:1: warning: symbol 'nfsd4_encode_fattr' was not declared. Should it be static?
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
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Note nobody's ever noticed because the typical client probably never
requests FILES_AVAIL without also requesting something else on the list.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: stable@vger.kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
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Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
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RPC_MAX_AUTH_SIZE is scattered around several places. Better to set it
once in the auth code, where this kind of estimate should be made. And
while we're at it we can leave it zero when we're not using krb5i or
krb5p.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
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And switch a couple other functions from the encode(&p,...) convention
to the p = encode(p,...) convention mostly used elsewhere.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
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Signed-off-by: J. Bruce Fields <bfields@redhat.com>
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Signed-off-by: J. Bruce Fields <bfields@redhat.com>
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These macros just obscure what's going on. Adopt the convention of the
client-side code.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
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encode_getattr, for example, can return nfserr_resource to indicate it
ran out of buffer space. That's not a legal error in the 4.1 case.
And in the 4.1 case, if we ran out of buffer space, we should have
exceeded a session limit too.
(Note in 1bc49d83c37cfaf46be357757e592711e67f9809 "nfsd4: fix
nfs4err_resource in 4.1 case" we originally tried fixing this error
return before fixing the problem that we could error out while we still
had lots of available space. The result was to trade one illegal error
for another in those cases. We decided that was helpful, so reverted
the change in fc208d026be0c7d60db9118583fc62f6ca97743d, and are only
reinstating it now that we've elimited almost all of those cases.)
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
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I'm not sure why a client would want to stuff multiple reads in a
single compound rpc, but it's legal for them to do it, and we should
really support it.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
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More cleanup, no change in functionality.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
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Trivial cleanup, no change in functionality.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
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The splice and readv cases are actually quite different--for example the
former case ignores the array of vectors we build up for the latter.
It is probably clearer to separate the two cases entirely.
There's some code duplication between the split out encoders, but this
is only temporary and will be fixed by a later patch.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
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We currently allow only one read per compound, with operations before
and after whose responses will require no more than about a page to
encode.
While we don't expect clients to violate those limits any time soon,
this limitation isn't really condoned by the spec, so to future proof
the server we should lift the limitation.
At the same time we'd like to continue to support zero-copy reads.
Supporting multiple zero-copy-reads per compound would require a new
data structure to replace struct xdr_buf, which can represent only one
set of included pages.
So for now we plan to modify encode_read() to support either zero-copy
or non-zero-copy reads, and use some heuristics at the start of the
compound processing to decide whether a zero-copy read will work.
This will allow us to support more exotic compounds without introducing
a performance regression in the normal case.
Later patches handle those "exotic compounds", this one just makes sure
zero-copy is turned off in those cases.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
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There's no advantage to this zero-copy-style readlink encoding, and it
unnecessarily limits the kinds of compounds we can handle. (In practice
I can't see why a client would want e.g. multiple readlink calls in a
comound, but it's probably a spec violation for us not to handle it.)
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
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As long as we're here, let's enforce the protocol's limit on the number
of directory entries to return in a readdir.
I don't think anyone's ever noticed our lack of enforcement, but maybe
there's more of a chance they will now that we allow larger readdirs.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
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Currently we limit readdir results to a single page. This can result in
a performance regression compared to NFSv3 when reading large
directories.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
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We can simplify session limit enforcement by restricting the xdr buflen
to the session size.
Also fix a preexisting bug: we should really have been taking into
account the auth-required space when comparing against session limits,
which are limits on the size of the entire rpc reply, including any krb5
overhead.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
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We don't necessarily want to assume that the buflen is the same
as the number of bytes available in the pages. We may have some reason
to set it to something less (for example, later patches will use a
smaller buflen to enforce session limits).
So, calculate the buflen relative to the previous buflen instead of
recalculating it from scratch.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
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Signed-off-by: J. Bruce Fields <bfields@redhat.com>
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Signed-off-by: J. Bruce Fields <bfields@redhat.com>
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It will turn out to be useful to have a more accurate estimate of reply
size; so, piggyback on the existing op reply-size estimators.
Also move nfsd4_max_reply to nfs4proc.c to get easier access to struct
nfsd4_operation and friends. (Thanks to Christoph Hellwig for pointing
out that simplification.)
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
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I ran into this corner case in testing: in theory clients can provide
state owners up to 1024 bytes long. In the sessions case there might be
a risk of this pushing us over the DRC slot size.
The conflicting owner isn't really that important, so let's humor a
client that provides a small maxresponsize_cached by allowing ourselves
to return without the conflicting owner instead of outright failing the
operation.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
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Limits on maxresp_sz mean that we only ever need to replay rpc's that
are contained entirely in the head.
The one exception is very small zero-copy reads. That's an odd corner
case as clients wouldn't normally ask those to be cached.
in any case, this seems a little more robust.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
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After this we can handle for example getattr of very large ACLs.
Read, readdir, readlink are still special cases with their own limits.
Also we can't handle a new operation starting close to the end of a
page.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
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Better variable name, some comments, etc.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
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Now that all op encoders can handle running out of space, we no longer
need to check the remaining size for every operation; only nonidempotent
operations need that check, and that can be done by
nfsd4_check_resp_size.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
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We're keeping the length updated as we go now, so there's no need for
the extra calculation here.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
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Once we've included page-cache pages in the encoding it's difficult to
remove them and restart encoding. (xdr_truncate_encode doesn't handle
that case.) So, make sure we'll have adequate space to finish the
operation first.
For now COMPOUND_SLACK_SPACE checks should prevent this case happening,
but we want to remove those checks.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
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We've tried to prevent running out of space with COMPOUND_SLACK_SPACE
and special checking in those operations (getattr) whose result can vary
enormously.
However:
- COMPOUND_SLACK_SPACE may be difficult to maintain as we add
more protocol.
- BUG_ON or page faulting on failure seems overly fragile.
- Especially in the 4.1 case, we prefer not to fail compounds
just because the returned result came *close* to session
limits. (Though perfect enforcement here may be difficult.)
- I'd prefer encoding to be uniform for all encoders instead of
having special exceptions for encoders containing, for
example, attributes.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
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Normally xdr encoding proceeds in a single pass from start of a buffer
to end, but sometimes we have to write a few bytes to an earlier
position.
Use write_bytes_to_xdr_buf for these cases rather than saving a pointer
to write to. We plan to rewrite xdr_reserve_space to handle encoding
across page boundaries using a scratch buffer, and don't want to risk
writing to a pointer that was contained in a scratch buffer.
Also it will no longer be safe to calculate lengths by subtracting two
pointers, so use xdr_buf offsets instead.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
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Now that lengths are reliable, we can use xdr_truncate instead of
open-coding it everywhere.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
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Signed-off-by: J. Bruce Fields <bfields@redhat.com>
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xdr_reserve_space should now be calculating the length correctly as we
go, so there's no longer any need to fix it up here.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
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