svcauth_gss: Close connection when dropping an incoming message

S5.3.3.1 of RFC 2203 requires that an incoming GSS-wrapped message
whose sequence number lies outside the current window i

svcauth_gss: Close connection when dropping an incoming message

S5.3.3.1 of RFC 2203 requires that an incoming GSS-wrapped message
whose sequence number lies outside the current window is dropped.
The rationale is:

The reason for discarding requests silently is that the server
is unable to determine if the duplicate or out of range request
was due to a sequencing problem in the client, network, or the
operating system, or due to some quirk in routing, or a replay
attack by an intruder. Discarding the request allows the client
to recover after timing out, if indeed the duplication was
unintentional or well intended.

However, clients may rely on the server dropping the connection to
indicate that a retransmit is needed. Without a connection reset, a
client can wait forever without retransmitting, and the workload
just stops dead. I've reproduced this behavior by running xfstests
generic/323 on an NFSv4.0 mount with proto=rdma and sec=krb5i.

To address this issue, have the server close the connection when it
silently discards an incoming message due to a GSS sequence number
problem.

There are a few other places where the server will never reply.
Change those spots in a similar fashion.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

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sunrpc: don't pass on-stack memory to sg_set_buf

As of ac4e97abce9b "scatterlist: sg_set_buf() argument must be in linear
mapping", sg_set_buf hits a BUG when make_checksum_v2->xdr_proce

sunrpc: don't pass on-stack memory to sg_set_buf

As of ac4e97abce9b "scatterlist: sg_set_buf() argument must be in linear
mapping", sg_set_buf hits a BUG when make_checksum_v2->xdr_process_buf,
among other callers, passes it memory on the stack.

We only need a scatterlist to pass this to the crypto code, and it seems
like overkill to require kmalloc'd memory just to encrypt a few bytes,
but for now this seems the best fix.

Many of these callers are in the NFS write paths, so we allocate with
GFP_NOFS. It might be possible to do without allocations here entirely,
but that would probably be a bigger project.

Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

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cred: simpler, 1D supplementary groups

Current supplementary groups code can massively overallocate memory and
is implemented in a way so that access to individual gid is done via 2D

cred: simpler, 1D supplementary groups

Current supplementary groups code can massively overallocate memory and
is implemented in a way so that access to individual gid is done via 2D
array.

If number of gids is <= 32, memory allocation is more or less tolerable
(140/148 bytes). But if it is not, code allocates full page (!)
regardless and, what's even more fun, doesn't reuse small 32-entry
array.

2D array means dependent shifts, loads and LEAs without possibility to
optimize them (gid is never known at compile time).

All of the above is unnecessary. Switch to the usual
trailing-zero-len-array scheme. Memory is allocated with
kmalloc/vmalloc() and only as much as needed. Accesses become simpler
(LEA 8(gi,idx,4) or even without displacement).

Maximum number of gids is 65536 which translates to 256KB+8 bytes. I
think kernel can handle such allocation.

On my usual desktop system with whole 9 (nine) aux groups, struct
group_info shrinks from 148 bytes to 44 bytes, yay!

Nice side effects:

- "gi->gid[i]" is shorter than "GROUP_AT(gi, i)", less typing,

- fix little mess in net/ipv4/ping.c
should have been using GROUP_AT macro but this point becomes moot,

- aux group allocation is persistent and should be accounted as such.

Link: http://lkml.kernel.org/r/20160817201927.GA2096@p183.telecom.by
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Vasily Kulikov <segoon@openwall.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

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svcauth_gss: Revert 64c59a3726f2 ("Remove unnecessary allocation")

rsc_lookup steals the passed-in memory to avoid doing an allocation of
its own, so we can't just pass in a pointer to m

svcauth_gss: Revert 64c59a3726f2 ("Remove unnecessary allocation")

rsc_lookup steals the passed-in memory to avoid doing an allocation of
its own, so we can't just pass in a pointer to memory that someone else
is using.

If we really want to avoid allocation there then maybe we should
preallocate somwhere, or reference count these handles.

For now we should revert.

On occasion I see this on my server:

kernel: kernel BUG at /home/cel/src/linux/linux-2.6/mm/slub.c:3851!
kernel: invalid opcode: 0000 [#1] SMP
kernel: Modules linked in: cts rpcsec_gss_krb5 sb_edac edac_core x86_pkg_temp_thermal intel_powerclamp coretemp kvm_intel kvm irqbypass crct10dif_pclmul crc32_pclmul ghash_clmulni_intel aesni_intel lrw gf128mul glue_helper ablk_helper cryptd btrfs xor iTCO_wdt iTCO_vendor_support raid6_pq pcspkr i2c_i801 i2c_smbus lpc_ich mfd_core mei_me sg mei shpchp wmi ioatdma ipmi_si ipmi_msghandler acpi_pad acpi_power_meter rpcrdma ib_ipoib rdma_ucm ib_ucm ib_uverbs ib_umad rdma_cm ib_cm iw_cm nfsd nfs_acl lockd grace auth_rpcgss sunrpc ip_tables xfs libcrc32c mlx4_ib mlx4_en ib_core sr_mod cdrom sd_mod ast drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops ttm drm crc32c_intel igb mlx4_core ahci libahci libata ptp pps_core dca i2c_algo_bit i2c_core dm_mirror dm_region_hash dm_log dm_mod
kernel: CPU: 7 PID: 145 Comm: kworker/7:2 Not tainted 4.8.0-rc4-00006-g9d06b0b #15
kernel: Hardware name: Supermicro Super Server/X10SRL-F, BIOS 1.0c 09/09/2015
kernel: Workqueue: events do_cache_clean [sunrpc]
kernel: task: ffff8808541d8000 task.stack: ffff880854344000
kernel: RIP: 0010:[<ffffffff811e7075>] [<ffffffff811e7075>] kfree+0x155/0x180
kernel: RSP: 0018:ffff880854347d70 EFLAGS: 00010246
kernel: RAX: ffffea0020fe7660 RBX: ffff88083f9db064 RCX: 146ff0f9d5ec5600
kernel: RDX: 000077ff80000000 RSI: ffff880853f01500 RDI: ffff88083f9db064
kernel: RBP: ffff880854347d88 R08: ffff8808594ee000 R09: ffff88087fdd8780
kernel: R10: 0000000000000000 R11: ffffea0020fe76c0 R12: ffff880853f01500
kernel: R13: ffffffffa013cf76 R14: ffffffffa013cff0 R15: ffffffffa04253a0
kernel: FS: 0000000000000000(0000) GS:ffff88087fdc0000(0000) knlGS:0000000000000000
kernel: CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
kernel: CR2: 00007fed60b020c3 CR3: 0000000001c06000 CR4: 00000000001406e0
kernel: Stack:
kernel: ffff8808589f2f00 ffff880853f01500 0000000000000001 ffff880854347da0
kernel: ffffffffa013cf76 ffff8808589f2f00 ffff880854347db8 ffffffffa013d006
kernel: ffff8808589f2f20 ffff880854347e00 ffffffffa0406f60 0000000057c7044f
kernel: Call Trace:
kernel: [<ffffffffa013cf76>] rsc_free+0x16/0x90 [auth_rpcgss]
kernel: [<ffffffffa013d006>] rsc_put+0x16/0x30 [auth_rpcgss]
kernel: [<ffffffffa0406f60>] cache_clean+0x2e0/0x300 [sunrpc]
kernel: [<ffffffffa04073ee>] do_cache_clean+0xe/0x70 [sunrpc]
kernel: [<ffffffff8109a70f>] process_one_work+0x1ff/0x3b0
kernel: [<ffffffff8109b15c>] worker_thread+0x2bc/0x4a0
kernel: [<ffffffff8109aea0>] ? rescuer_thread+0x3a0/0x3a0
kernel: [<ffffffff810a0ba4>] kthread+0xe4/0xf0
kernel: [<ffffffff8169c47f>] ret_from_fork+0x1f/0x40
kernel: [<ffffffff810a0ac0>] ? kthread_stop+0x110/0x110
kernel: Code: f7 ff ff eb 3b 65 8b 05 da 30 e2 7e 89 c0 48 0f a3 05 a0 38 b8 00 0f 92 c0 84 c0 0f 85 d1 fe ff ff 0f 1f 44 00 00 e9 f5 fe ff ff <0f> 0b 49 8b 03 31 f6 f6 c4 40 0f 85 62 ff ff ff e9 61 ff ff ff
kernel: RIP [<ffffffff811e7075>] kfree+0x155/0x180
kernel: RSP <ffff880854347d70>
kernel: ---[ end trace 3fdec044969def26 ]---

It seems to be most common after a server reboot where a client has been
using a Kerberos mount, and reconnects to continue its workload.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Cc: stable@vger.kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

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sunrpc: add gss minor status to svcauth_gss_proxy_init

GSS-Proxy doesn't produce very much debug logging at all. Printing out
the gss minor status will aid in troubleshooting if the

sunrpc: add gss minor status to svcauth_gss_proxy_init

GSS-Proxy doesn't produce very much debug logging at all. Printing out
the gss minor status will aid in troubleshooting if the
GSS_Accept_sec_context upcall fails.

Signed-off-by: Scott Mayhew <smayhew@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

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sunrpc: fix stripping of padded MIC tokens

The length of the GSS MIC token need not be a multiple of four bytes.
It is then padded by XDR to a multiple of 4 B, but unwrap_integ_data()

sunrpc: fix stripping of padded MIC tokens

The length of the GSS MIC token need not be a multiple of four bytes.
It is then padded by XDR to a multiple of 4 B, but unwrap_integ_data()
would previously only trim mic.len + 4 B. The remaining up to three
bytes would then trigger a check in nfs4svc_decode_compoundargs(),
leading to a "garbage args" error and mount failure:

nfs4svc_decode_compoundargs: compound not properly padded!
nfsd: failed to decode arguments!

This would prevent older clients using the pre-RFC 4121 MIC format
(37-byte MIC including a 9-byte OID) from mounting exports from v3.9+
servers using krb5i.

The trimming was introduced by commit 4c190e2f913f ("sunrpc: trim off
trailing checksum before returning decrypted or integrity authenticated
buffer").

Fixes: 4c190e2f913f "unrpc: trim off trailing checksum..."
Signed-off-by: Tomáš Trnka <ttrnka@mail.muni.cz>
Cc: stable@vger.kernel.org
Acked-by: Jeff Layton <jlayton@poochiereds.net>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

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Remove unnecessary allocation

Reported-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

sunrpc: integer underflow in rsc_parse()

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

sunrpc: integer underflow in rsc_parse()

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>

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sunrpc: move rq_splice_ok flag into rq_flags

Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

sunrpc: eliminate RPC_DEBUG

It's always set to whatever CONFIG_SUNRPC_DEBUG is, so just use that.

Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: Trond Mykle

sunrpc: eliminate RPC_DEBUG

It's always set to whatever CONFIG_SUNRPC_DEBUG is, so just use that.

Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>

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SUNRPC/NFSD: Change to type of bool for rq_usedeferral and rq_splice_ok

rq_usedeferral and rq_splice_ok are used as 0 and 1, just defined to bool.

Signed-off-by: Kinglong Mee <kingl

SUNRPC/NFSD: Change to type of bool for rq_usedeferral and rq_splice_ok

rq_usedeferral and rq_splice_ok are used as 0 and 1, just defined to bool.

Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

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nfsd4: better reservation of head space for krb5

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

nfsd4: better reservation of head space for krb5

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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minor svcauth_gss.c cleanup

sunrpc: get rid of use_gssp_lock

We can achieve the same result with a cmpxchg(). This also fixes a
potential race in use_gss_proxy(). The value of sn->use_gss_proxy could
go from -1

sunrpc: get rid of use_gssp_lock

We can achieve the same result with a cmpxchg(). This also fixes a
potential race in use_gss_proxy(). The value of sn->use_gss_proxy could
go from -1 to 1 just after we check it in use_gss_proxy() but before we
acquire the spinlock. The procfile write would end up returning success
but the value would flip to 0 soon afterward. With this method we not
only avoid locking but the first "setter" always wins.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

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sunrpc: fix potential race between setting use_gss_proxy and the upcall rpc_clnt

An nfsd thread can call use_gss_proxy and find it set to '1' but find
gssp_clnt still NULL, so that when

sunrpc: fix potential race between setting use_gss_proxy and the upcall rpc_clnt

An nfsd thread can call use_gss_proxy and find it set to '1' but find
gssp_clnt still NULL, so that when it attempts the upcall the result
will be an unnecessary -EIO.

So, ensure that gssp_clnt is created first, and set the use_gss_proxy
variable only if that succeeds.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

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sunrpc: don't wait for write before allowing reads from use-gss-proxy file

It doesn't make much sense to make reads from this procfile hang. As
far as I can tell, only gssproxy itself wi

sunrpc: don't wait for write before allowing reads from use-gss-proxy file

It doesn't make much sense to make reads from this procfile hang. As
far as I can tell, only gssproxy itself will open this file and it
never reads from it. Change it to just give the present setting of
sn->use_gss_proxy without waiting for anything.

Note that we do not want to call use_gss_proxy() in this codepath
since an inopportune read of this file could cause it to be disabled
prematurely.

Cc: stable@vger.kernel.org
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

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svcrpc: fix error-handling on badd gssproxy downcall

For every other problem here we bail out with an error, but here for
some reason we're setting a negative cache entry (with, note, an

svcrpc: fix error-handling on badd gssproxy downcall

For every other problem here we bail out with an error, but here for
some reason we're setting a negative cache entry (with, note, an
undefined expiry).

It seems simplest just to bail out in the same way as we do in other
cases.

Cc: Simo Sorce <simo@redhat.com>
Reported-by: Andi Kleen <andi@firstfloor.org>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

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svcrpc: set cr_gss_mech from gss-proxy as well as legacy upcall

The change made to rsc_parse() in
0dc1531aca7fd1440918bd55844a054e9c29acad "svcrpc: store gss mech in
svc_cred" should

svcrpc: set cr_gss_mech from gss-proxy as well as legacy upcall

The change made to rsc_parse() in
0dc1531aca7fd1440918bd55844a054e9c29acad "svcrpc: store gss mech in
svc_cred" should also have been propagated to the gss-proxy codepath.
This fixes a crash in the gss-proxy case.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>

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Merge branch 'for-3.11' of git://linux-nfs.org/~bfields/linux

Pull nfsd changes from Bruce Fields:
"Changes this time include:

- 4.1 enabled on the server by default: the la

Merge branch 'for-3.11' of git://linux-nfs.org/~bfields/linux

Pull nfsd changes from Bruce Fields:
"Changes this time include:

- 4.1 enabled on the server by default: the last 4.1-specific issues
I know of are fixed, so we're not going to find the rest of the
bugs without more exposure.
- Experimental support for NFSv4.2 MAC Labeling (to allow running
selinux over NFS), from Dave Quigley.
- Fixes for some delicate cache/upcall races that could cause rare
server hangs; thanks to Neil Brown and Bodo Stroesser for extreme
debugging persistence.
- Fixes for some bugs found at the recent NFS bakeathon, mostly v4
and v4.1-specific, but also a generic bug handling fragmented rpc
calls"

* 'for-3.11' of git://linux-nfs.org/~bfields/linux: (31 commits)
nfsd4: support minorversion 1 by default
nfsd4: allow destroy_session over destroyed session
svcrpc: fix failures to handle -1 uid's
sunrpc: Don't schedule an upcall on a replaced cache entry.
net/sunrpc: xpt_auth_cache should be ignored when expired.
sunrpc/cache: ensure items removed from cache do not have pending upcalls.
sunrpc/cache: use cache_fresh_unlocked consistently and correctly.
sunrpc/cache: remove races with queuing an upcall.
nfsd4: return delegation immediately if lease fails
nfsd4: do not throw away 4.1 lock state on last unlock
nfsd4: delegation-based open reclaims should bypass permissions
svcrpc: don't error out on small tcp fragment
svcrpc: fix handling of too-short rpc's
nfsd4: minor read_buf cleanup
nfsd4: fix decoding of compounds across page boundaries
nfsd4: clean up nfs4_open_delegation
NFSD: Don't give out read delegations on creates
nfsd4: allow client to send no cb_sec flavors
nfsd4: fail attempts to request gss on the backchannel
nfsd4: implement minimal SP4_MACH_CRED
...

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svcrpc: store gss mech in svc_cred

Store a pointer to the gss mechanism used in the rq_cred and cl_cred.
This will make it easier to enforce SP4_MACH_CRED, which needs to
compare the

svcrpc: store gss mech in svc_cred

Store a pointer to the gss mechanism used in the rq_cred and cl_cred.
This will make it easier to enforce SP4_MACH_CRED, which needs to
compare the mechanism used on the exchange_id with that used on
protected operations.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>

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svcrpc: introduce init_svc_cred

Common helper to zero out fields of the svc_cred.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>

more open-coded file_inode() calls

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

svcrpc: implement O_NONBLOCK behavior for use-gss-proxy

Somebody noticed LTP was complaining about O_NONBLOCK opens of
/proc/net/rpc/use-gss-proxy succeeding and then a following read

svcrpc: implement O_NONBLOCK behavior for use-gss-proxy

Somebody noticed LTP was complaining about O_NONBLOCK opens of
/proc/net/rpc/use-gss-proxy succeeding and then a following read
hanging.

I'm not convinced LTP really has any business opening random proc files
and expecting them to behave a certain way. Maybe this isn't really a
bug.

But in any case the O_NONBLOCK behavior could be useful for someone that
wants to test whether gss-proxy is up without waiting.

Reported-by: Jan Stancek <jstancek@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

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svcauth_gss: fix error code in use_gss_proxy()

This should return zero on success and -EBUSY on error so the type
needs to be int instead of bool.

Signed-off-by: Dan Carpenter <

svcauth_gss: fix error code in use_gss_proxy()

This should return zero on success and -EBUSY on error so the type
needs to be int instead of bool.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

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Merge branch 'for-3.10' of git://linux-nfs.org/~bfields/linux

Pull nfsd changes from J Bruce Fields:
"Highlights include:

- Some more DRC cleanup and performance work from J

Merge branch 'for-3.10' of git://linux-nfs.org/~bfields/linux

Pull nfsd changes from J Bruce Fields:
"Highlights include:

- Some more DRC cleanup and performance work from Jeff Layton

- A gss-proxy upcall from Simo Sorce: currently krb5 mounts to the
server using credentials from Active Directory often fail due to
limitations of the svcgssd upcall interface. This replacement
lifts those limitations. The existing upcall is still supported
for backwards compatibility.

- More NFSv4.1 support: at this point, if a user with a current
client who upgrades from 4.0 to 4.1 should see no regressions. In
theory we do everything a 4.1 server is required to do. Patches
for a couple minor exceptions are ready for 3.11, and with those
and some more testing I'd like to turn 4.1 on by default in 3.11."

Fix up semantic conflict as per Stephen Rothwell and linux-next:

Commit 030d794bf498 ("SUNRPC: Use gssproxy upcall for server RPCGSS
authentication") adds two new users of "PDE(inode)->data", but we're
supposed to use "PDE_DATA(inode)" instead since commit d9dda78bad87
("procfs: new helper - PDE_DATA(inode)").

The old PDE() macro is no longer available since commit c30480b92cf4
("proc: Make the PROC_I() and PDE() macros internal to procfs")

* 'for-3.10' of git://linux-nfs.org/~bfields/linux: (60 commits)
NFSD: SECINFO doesn't handle unsupported pseudoflavors correctly
NFSD: Simplify GSS flavor encoding in nfsd4_do_encode_secinfo()
nfsd: make symbol nfsd_reply_cache_shrinker static
svcauth_gss: fix error return code in rsc_parse()
nfsd4: don't remap EISDIR errors in rename
svcrpc: fix gss-proxy to respect user namespaces
SUNRPC: gssp_procedures[] can be static
SUNRPC: define {create,destroy}_use_gss_proxy_proc_entry in !PROC case
nfsd4: better error return to indicate SSV non-support
nfsd: fix EXDEV checking in rename
SUNRPC: Use gssproxy upcall for server RPCGSS authentication.
SUNRPC: Add RPC based upcall mechanism for RPCGSS auth
SUNRPC: conditionally return endtime from import_sec_context
SUNRPC: allow disabling idle timeout
SUNRPC: attempt AF_LOCAL connect on setup
nfsd: Decode and send 64bit time values
nfsd4: put_client_renew_locked can be static
nfsd4: remove unused macro
nfsd4: remove some useless code
nfsd4: implement SEQ4_STATUS_RECALLABLE_STATE_REVOKED
...

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