Commit Graph

139 Commits

Author SHA1 Message Date
Vakul Garg
a88c26f671 net/tls: Replace kfree_skb() with consume_skb()
To free the skb in normal course of processing, consume_skb() should be
used. Only for failure paths, skb_free() is intended to be used.

https://www.kernel.org/doc/htmldocs/networking/API-consume-skb.html

Signed-off-by: Vakul Garg <vakul.garg@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-03-21 10:14:26 -07:00
Vakul Garg
f295b3ae9f net/tls: Add support of AES128-CCM based ciphers
Added support for AES128-CCM based record encryption. AES128-CCM is
similar to AES128-GCM. Both of them have same salt/iv/mac size. The
notable difference between the two is that while invoking AES128-CCM
operation, the salt||nonce (which is passed as IV) has to be prefixed
with a hardcoded value '2'. Further, CCM implementation in kernel
requires IV passed in crypto_aead_request() to be full '16' bytes.
Therefore, the record structure 'struct tls_rec' has been modified to
reserve '16' bytes for IV. This works for both GCM and CCM based cipher.

Signed-off-by: Vakul Garg <vakul.garg@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-03-20 11:02:05 -07:00
Vakul Garg
4504ab0e6e net/tls: Inform user space about send buffer availability
A previous fix ("tls: Fix write space handling") assumed that
user space application gets informed about the socket send buffer
availability when tls_push_sg() gets called. Inside tls_push_sg(), in
case do_tcp_sendpages() returns 0, the function returns without calling
ctx->sk_write_space. Further, the new function tls_sw_write_space()
did not invoke ctx->sk_write_space. This leads to situation that user
space application encounters a lockup always waiting for socket send
buffer to become available.

Rather than call ctx->sk_write_space from tls_push_sg(), it should be
called from tls_write_space. So whenever tcp stack invokes
sk->sk_write_space after freeing socket send buffer, we always declare
the same to user space by the way of invoking ctx->sk_write_space.

Fixes: 7463d3a2db ("tls: Fix write space handling")
Signed-off-by: Vakul Garg <vakul.garg@nxp.com>
Reviewed-by: Boris Pismenny <borisp@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-03-13 14:16:44 -07:00
Boris Pismenny
d069b780e3 tls: Fix tls_device receive
Currently, the receive function fails to handle records already
decrypted by the device due to the commit mentioned below.

This commit advances the TLS record sequence number and prepares the context
to handle the next record.

Fixes: fedf201e12 ("net: tls: Refactor control message handling on recv")
Signed-off-by: Boris Pismenny <borisp@mellanox.com>
Reviewed-by: Eran Ben Elisha <eranbe@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-03-03 22:10:16 -08:00
Eran Ben Elisha
7754bd63ed tls: Fix mixing between async capable and async
Today, tls_sw_recvmsg is capable of using asynchronous mode to handle
application data TLS records. Moreover, it assumes that if the cipher
can be handled asynchronously, then all packets will be processed
asynchronously.

However, this assumption is not always true. Specifically, for AES-GCM
in TLS1.2, it causes data corruption, and breaks user applications.

This patch fixes this problem by separating the async capability from
the decryption operation result.

Fixes: c0ab4732d4 ("net/tls: Do not use async crypto for non-data records")
Signed-off-by: Eran Ben Elisha <eranbe@mellanox.com>
Reviewed-by: Boris Pismenny <borisp@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-03-03 22:10:16 -08:00
Boris Pismenny
7463d3a2db tls: Fix write space handling
TLS device cannot use the sw context. This patch returns the original
tls device write space handler and moves the sw/device specific portions
to the relevant files.

Also, we remove the write_space call for the tls_sw flow, because it
handles partial records in its delayed tx work handler.

Fixes: a42055e8d2 ("net/tls: Add support for async encryption of records for performance")
Signed-off-by: Boris Pismenny <borisp@mellanox.com>
Reviewed-by: Eran Ben Elisha <eranbe@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-03-03 22:10:16 -08:00
Boris Pismenny
94850257cf tls: Fix tls_device handling of partial records
Cleanup the handling of partial records while fixing a bug where the
tls_push_pending_closed_record function is using the software tls
context instead of the hardware context.

The bug resulted in the following crash:
[   88.791229] BUG: unable to handle kernel NULL pointer dereference at 0000000000000000
[   88.793271] #PF error: [normal kernel read fault]
[   88.794449] PGD 800000022a426067 P4D 800000022a426067 PUD 22a156067 PMD 0
[   88.795958] Oops: 0000 [#1] SMP PTI
[   88.796884] CPU: 2 PID: 4973 Comm: openssl Not tainted 5.0.0-rc4+ #3
[   88.798314] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
[   88.800067] RIP: 0010:tls_tx_records+0xef/0x1d0 [tls]
[   88.801256] Code: 00 02 48 89 43 08 e8 a0 0b 96 d9 48 89 df e8 48 dd
4d d9 4c 89 f8 4d 8b bf 98 00 00 00 48 05 98 00 00 00 48 89 04 24 49 39
c7 <49> 8b 1f 4d 89 fd 0f 84 af 00 00 00 41 8b 47 10 85 c0 0f 85 8d 00
[   88.805179] RSP: 0018:ffffbd888186fca8 EFLAGS: 00010213
[   88.806458] RAX: ffff9af1ed657c98 RBX: ffff9af1e88a1980 RCX: 0000000000000000
[   88.808050] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff9af1e88a1980
[   88.809724] RBP: ffff9af1e88a1980 R08: 0000000000000017 R09: ffff9af1ebeeb700
[   88.811294] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
[   88.812917] R13: ffff9af1e88a1980 R14: ffff9af1ec13f800 R15: 0000000000000000
[   88.814506] FS:  00007fcad2240740(0000) GS:ffff9af1f7880000(0000) knlGS:0000000000000000
[   88.816337] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   88.817717] CR2: 0000000000000000 CR3: 0000000228b3e000 CR4: 00000000001406e0
[   88.819328] Call Trace:
[   88.820123]  tls_push_data+0x628/0x6a0 [tls]
[   88.821283]  ? remove_wait_queue+0x20/0x60
[   88.822383]  ? n_tty_read+0x683/0x910
[   88.823363]  tls_device_sendmsg+0x53/0xa0 [tls]
[   88.824505]  sock_sendmsg+0x36/0x50
[   88.825492]  sock_write_iter+0x87/0x100
[   88.826521]  __vfs_write+0x127/0x1b0
[   88.827499]  vfs_write+0xad/0x1b0
[   88.828454]  ksys_write+0x52/0xc0
[   88.829378]  do_syscall_64+0x5b/0x180
[   88.830369]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
[   88.831603] RIP: 0033:0x7fcad1451680

[ 1248.470626] BUG: unable to handle kernel NULL pointer dereference at 0000000000000000
[ 1248.472564] #PF error: [normal kernel read fault]
[ 1248.473790] PGD 0 P4D 0
[ 1248.474642] Oops: 0000 [#1] SMP PTI
[ 1248.475651] CPU: 3 PID: 7197 Comm: openssl Tainted: G           OE 5.0.0-rc4+ #3
[ 1248.477426] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
[ 1248.479310] RIP: 0010:tls_tx_records+0x110/0x1f0 [tls]
[ 1248.480644] Code: 00 02 48 89 43 08 e8 4f cb 63 d7 48 89 df e8 f7 9c
1b d7 4c 89 f8 4d 8b bf 98 00 00 00 48 05 98 00 00 00 48 89 04 24 49 39
c7 <49> 8b 1f 4d 89 fd 0f 84 af 00 00 00 41 8b 47 10 85 c0 0f 85 8d 00
[ 1248.484825] RSP: 0018:ffffaa0a41543c08 EFLAGS: 00010213
[ 1248.486154] RAX: ffff955a2755dc98 RBX: ffff955a36031980 RCX: 0000000000000006
[ 1248.487855] RDX: 0000000000000000 RSI: 000000000000002b RDI: 0000000000000286
[ 1248.489524] RBP: ffff955a36031980 R08: 0000000000000000 R09: 00000000000002b1
[ 1248.491394] R10: 0000000000000003 R11: 00000000ad55ad55 R12: 0000000000000000
[ 1248.493162] R13: 0000000000000000 R14: ffff955a2abe6c00 R15: 0000000000000000
[ 1248.494923] FS:  0000000000000000(0000) GS:ffff955a378c0000(0000) knlGS:0000000000000000
[ 1248.496847] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 1248.498357] CR2: 0000000000000000 CR3: 000000020c40e000 CR4: 00000000001406e0
[ 1248.500136] Call Trace:
[ 1248.500998]  ? tcp_check_oom+0xd0/0xd0
[ 1248.502106]  tls_sk_proto_close+0x127/0x1e0 [tls]
[ 1248.503411]  inet_release+0x3c/0x60
[ 1248.504530]  __sock_release+0x3d/0xb0
[ 1248.505611]  sock_close+0x11/0x20
[ 1248.506612]  __fput+0xb4/0x220
[ 1248.507559]  task_work_run+0x88/0xa0
[ 1248.508617]  do_exit+0x2cb/0xbc0
[ 1248.509597]  ? core_sys_select+0x17a/0x280
[ 1248.510740]  do_group_exit+0x39/0xb0
[ 1248.511789]  get_signal+0x1d0/0x630
[ 1248.512823]  do_signal+0x36/0x620
[ 1248.513822]  exit_to_usermode_loop+0x5c/0xc6
[ 1248.515003]  do_syscall_64+0x157/0x180
[ 1248.516094]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
[ 1248.517456] RIP: 0033:0x7fb398bd3f53
[ 1248.518537] Code: Bad RIP value.

Fixes: a42055e8d2 ("net/tls: Add support for async encryption of records for performance")
Signed-off-by: Boris Pismenny <borisp@mellanox.com>
Signed-off-by: Eran Ben Elisha <eranbe@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-03-03 22:10:16 -08:00
Vakul Garg
2b794c4098 tls: Return type of non-data records retrieved using MSG_PEEK in recvmsg
The patch enables returning 'type' in msghdr for records that are
retrieved with MSG_PEEK in recvmsg. Further it prevents records peeked
from socket from getting clubbed with any other record of different
type when records are subsequently dequeued from strparser.

For each record, we now retain its type in sk_buff's control buffer
cb[]. Inside control buffer, record's full length and offset are already
stored by strparser in 'struct strp_msg'. We store record type after
'struct strp_msg' inside 'struct tls_msg'. For tls1.2, the type is
stored just after record dequeue. For tls1.3, the type is stored after
record has been decrypted.

Inside process_rx_list(), before processing a non-data record, we check
that we must be able to return back the record type to the user
application. If not, the decrypted records in tls context's rx_list is
left there without consuming any data.

Fixes: 692d7b5d1f ("tls: Fix recvmsg() to be able to peek across multiple records")
Signed-off-by: Vakul Garg <vakul.garg@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-24 21:58:38 -08:00
Vakul Garg
4509de1468 net/tls: Move protocol constants from cipher context to tls context
Each tls context maintains two cipher contexts (one each for tx and rx
directions). For each tls session, the constants such as protocol
version, ciphersuite, iv size, associated data size etc are same for
both the directions and need to be stored only once per tls context.
Hence these are moved from 'struct cipher_context' to 'struct
tls_prot_info' and stored only once in 'struct tls_context'.

Signed-off-by: Vakul Garg <vakul.garg@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-19 10:40:36 -08:00
Vakul Garg
c0ab4732d4 net/tls: Do not use async crypto for non-data records
Addition of tls1.3 support broke tls1.2 handshake when async crypto
accelerator is used. This is because the record type for non-data
records is not propagated to user application. Also when async
decryption happens, the decryption does not stop when two different
types of records get dequeued and submitted for decryption. To address
it, we decrypt tls1.2 non-data records in synchronous way. We check
whether the record we just processed has same type as the previous one
before checking for async condition and jumping to dequeue next record.

Fixes: 130b392c6c ("net: tls: Add tls 1.3 support")
Signed-off-by: Vakul Garg <vakul.garg@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-12 12:35:14 -05:00
Vakul Garg
8497ded2d1 net/tls: Disable async decrytion for tls1.3
Function tls_sw_recvmsg() dequeues multiple records from stream parser
and decrypts them. In case the decryption is done by async accelerator,
the records may get submitted for decryption while the previous ones may
not have been decryted yet. For tls1.3, the record type is known only
after decryption. Therefore, for tls1.3, tls_sw_recvmsg() may submit
records for decryption even if it gets 'handshake' records after 'data'
records. These intermediate 'handshake' records may do a key updation.
By the time new keys are given to ktls by userspace, it is possible that
ktls has already submitted some records i(which are encrypted with new
keys) for decryption using old keys. This would lead to decrypt failure.
Therefore, async decryption of records should be disabled for tls1.3.

Fixes: 130b392c6c ("net: tls: Add tls 1.3 support")
Signed-off-by: Vakul Garg <vakul.garg@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-09 09:27:49 -08:00
Dave Watson
5b053e121f net: tls: Set async_capable for tls zerocopy only if we see EINPROGRESS
Currently we don't zerocopy if the crypto framework async bit is set.
However some crypto algorithms (such as x86 AESNI) support async,
but in the context of sendmsg, will never run asynchronously.  Instead,
check for actual EINPROGRESS return code before assuming algorithm is
async.

Signed-off-by: Dave Watson <davejwatson@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-01 15:05:07 -08:00
Dave Watson
130b392c6c net: tls: Add tls 1.3 support
TLS 1.3 has minor changes from TLS 1.2 at the record layer.

* Header now hardcodes the same version and application content type in
  the header.
* The real content type is appended after the data, before encryption (or
  after decryption).
* The IV is xored with the sequence number, instead of concatinating four
  bytes of IV with the explicit IV.
* Zero-padding:  No exlicit length is given, we search backwards from the
  end of the decrypted data for the first non-zero byte, which is the
  content type.  Currently recv supports reading zero-padding, but there
  is no way for send to add zero padding.

Signed-off-by: Dave Watson <davejwatson@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-01 15:00:55 -08:00
Dave Watson
fedf201e12 net: tls: Refactor control message handling on recv
For TLS 1.3, the control message is encrypted.  Handle control
message checks after decryption.

Signed-off-by: Dave Watson <davejwatson@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-01 15:00:55 -08:00
Dave Watson
a2ef9b6a22 net: tls: Refactor tls aad space size calculation
TLS 1.3 has a different AAD size, use a variable in the code to
make TLS 1.3 support easy.

Signed-off-by: Dave Watson <davejwatson@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-01 15:00:55 -08:00
Dave Watson
fb99bce712 net: tls: Support 256 bit keys
Wire up support for 256 bit keys from the setsockopt to the crypto
framework

Signed-off-by: Dave Watson <davejwatson@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-01 15:00:55 -08:00
David S. Miller
eaf2a47f40 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2019-01-29 21:18:54 -08:00
Dave Watson
1023121375 net: tls: Fix deadlock in free_resources tx
If there are outstanding async tx requests (when crypto returns EINPROGRESS),
there is a potential deadlock: the tx work acquires the lock, while we
cancel_delayed_work_sync() while holding the lock.  Drop the lock while waiting
for the work to complete.

Fixes: a42055e8d2 ("Add support for async encryption of records...")
Signed-off-by: Dave Watson <davejwatson@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-28 23:07:08 -08:00
Dave Watson
32eb67b93c net: tls: Save iv in tls_rec for async crypto requests
aead_request_set_crypt takes an iv pointer, and we change the iv
soon after setting it.  Some async crypto algorithms don't save the iv,
so we need to save it in the tls_rec for async requests.

Found by hardcoding x64 aesni to use async crypto manager (to test the async
codepath), however I don't think this combination can happen in the wild.
Presumably other hardware offloads will need this fix, but there have been
no user reports.

Fixes: a42055e8d2 ("Add support for async encryption of records...")
Signed-off-by: Dave Watson <davejwatson@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-28 23:05:55 -08:00
Atul Gupta
76f7164d02 net/tls: free ctx in sock destruct
free tls context in sock destruct. close may not be the last
call to free sock but force releasing the ctx in close
will result in GPF when ctx referred again in tcp_done

[  515.330477] general protection fault: 0000 [#1] SMP PTI
[  515.330539] CPU: 5 PID: 0 Comm: swapper/5 Not tainted 4.20.0-rc7+ #10
[  515.330657] Hardware name: Supermicro X8ST3/X8ST3, BIOS 2.0b
11/07/2013
[  515.330844] RIP: 0010:tls_hw_unhash+0xbf/0xd0
[
[  515.332220] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  515.332340] CR2: 00007fab32c55000 CR3: 000000009261e000 CR4:
00000000000006e0
[  515.332519] Call Trace:
[  515.332632]  <IRQ>
[  515.332793]  tcp_set_state+0x5a/0x190
[  515.332907]  ? tcp_update_metrics+0xe3/0x350
[  515.333023]  tcp_done+0x31/0xd0
[  515.333130]  tcp_rcv_state_process+0xc27/0x111a
[  515.333242]  ? __lock_is_held+0x4f/0x90
[  515.333350]  ? tcp_v4_do_rcv+0xaf/0x1e0
[  515.333456]  tcp_v4_do_rcv+0xaf/0x1e0

Signed-off-by: Atul Gupta <atul.gupta@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-22 11:30:54 -08:00
Atul Gupta
63a6b3fee4 net/tls: build_protos moved to common routine
build protos is required for tls_hw_prot also hence moved to
'tls_build_proto' and called as required from tls_init
and tls_hw_proto. This is required since build_protos
for v4 is moved from tls_register to tls_init in
commit <28cb6f1eaffdc5a6a9707cac55f4a43aa3fd7895>

Signed-off-by: Atul Gupta <atul.gupta@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-22 11:30:54 -08:00
Vakul Garg
692d7b5d1f tls: Fix recvmsg() to be able to peek across multiple records
This fixes recvmsg() to be able to peek across multiple tls records.
Without this patch, the tls's selftests test case
'recv_peek_large_buf_mult_recs' fails. Each tls receive context now
maintains a 'rx_list' to retain incoming skb carrying tls records. If a
tls record needs to be retained e.g. for peek case or for the case when
the buffer passed to recvmsg() has a length smaller than decrypted
record length, then it is added to 'rx_list'. Additionally, records are
added in 'rx_list' if the crypto operation runs in async mode. The
records are dequeued from 'rx_list' after the decrypted data is consumed
by copying into the buffer passed to recvmsg(). In case, the MSG_PEEK
flag is used in recvmsg(), then records are not consumed or removed
from the 'rx_list'.

Signed-off-by: Vakul Garg <vakul.garg@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-17 14:20:40 -08:00
YueHaibing
01cb8a1a64 net/tls: Make function tls_sw_do_sendpage static
Fixes the following sparse warning:

 net/tls/tls_sw.c:1023:5: warning:
 symbol 'tls_sw_do_sendpage' was not declared. Should it be static?

Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-17 11:45:21 -08:00
YueHaibing
f3de19af0f net/tls: remove unused function tls_sw_sendpage_locked
There are no in-tree callers.

Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-17 11:44:58 -08:00
David S. Miller
ce28bb4453 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-12-21 15:06:20 -08:00
Vakul Garg
65a10e28ae tls: Do not call sk_memcopy_from_iter with zero length
In some conditions e.g. when tls_clone_plaintext_msg() returns -ENOSPC,
the number of bytes to be copied using subsequent function
sk_msg_memcopy_from_iter() becomes zero. This causes function
sk_msg_memcopy_from_iter() to fail which in turn causes tls_sw_sendmsg()
to return failure. To prevent it, do not call sk_msg_memcopy_from_iter()
when number of bytes to copy (indicated by 'try_to_copy') is zero.

Fixes: d829e9c411 ("tls: convert to generic sk_msg interface")
Signed-off-by: Vakul Garg <vakul.garg@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-12-21 10:26:54 -08:00
David S. Miller
339bbff2d6 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Daniel Borkmann says:

====================
pull-request: bpf-next 2018-12-21

The following pull-request contains BPF updates for your *net-next* tree.

There is a merge conflict in test_verifier.c. Result looks as follows:

        [...]
        },
        {
                "calls: cross frame pruning",
                .insns = {
                [...]
                .prog_type = BPF_PROG_TYPE_SOCKET_FILTER,
                .errstr_unpriv = "function calls to other bpf functions are allowed for root only",
                .result_unpriv = REJECT,
                .errstr = "!read_ok",
                .result = REJECT,
	},
        {
                "jset: functional",
                .insns = {
        [...]
        {
                "jset: unknown const compare not taken",
                .insns = {
                        BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
                                     BPF_FUNC_get_prandom_u32),
                        BPF_JMP_IMM(BPF_JSET, BPF_REG_0, 1, 1),
                        BPF_LDX_MEM(BPF_B, BPF_REG_8, BPF_REG_9, 0),
                        BPF_EXIT_INSN(),
                },
                .prog_type = BPF_PROG_TYPE_SOCKET_FILTER,
                .errstr_unpriv = "!read_ok",
                .result_unpriv = REJECT,
                .errstr = "!read_ok",
                .result = REJECT,
        },
        [...]
        {
                "jset: range",
                .insns = {
                [...]
                },
                .prog_type = BPF_PROG_TYPE_SOCKET_FILTER,
                .result_unpriv = ACCEPT,
                .result = ACCEPT,
        },

The main changes are:

1) Various BTF related improvements in order to get line info
   working. Meaning, verifier will now annotate the corresponding
   BPF C code to the error log, from Martin and Yonghong.

2) Implement support for raw BPF tracepoints in modules, from Matt.

3) Add several improvements to verifier state logic, namely speeding
   up stacksafe check, optimizations for stack state equivalence
   test and safety checks for liveness analysis, from Alexei.

4) Teach verifier to make use of BPF_JSET instruction, add several
   test cases to kselftests and remove nfp specific JSET optimization
   now that verifier has awareness, from Jakub.

5) Improve BPF verifier's slot_type marking logic in order to
   allow more stack slot sharing, from Jiong.

6) Add sk_msg->size member for context access and add set of fixes
   and improvements to make sock_map with kTLS usable with openssl
   based applications, from John.

7) Several cleanups and documentation updates in bpftool as well as
   auto-mount of tracefs for "bpftool prog tracelog" command,
   from Quentin.

8) Include sub-program tags from now on in bpf_prog_info in order to
   have a reliable way for user space to get all tags of the program
   e.g. needed for kallsyms correlation, from Song.

9) Add BTF annotations for cgroup_local_storage BPF maps and
   implement bpf fs pretty print support, from Roman.

10) Fix bpftool in order to allow for cross-compilation, from Ivan.

11) Update of bpftool license to GPLv2-only + BSD-2-Clause in order
    to be compatible with libbfd and allow for Debian packaging,
    from Jakub.

12) Remove an obsolete prog->aux sanitation in dump and get rid of
    version check for prog load, from Daniel.

13) Fix a memory leak in libbpf's line info handling, from Prashant.

14) Fix cpumap's frame alignment for build_skb() so that skb_shared_info
    does not get unaligned, from Jesper.

15) Fix test_progs kselftest to work with older compilers which are less
    smart in optimizing (and thus throwing build error), from Stanislav.

16) Cleanup and simplify AF_XDP socket teardown, from Björn.

17) Fix sk lookup in BPF kselftest's test_sock_addr with regards
    to netns_id argument, from Andrey.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-12-20 17:31:36 -08:00
John Fastabend
28cb6f1eaf bpf: tls_sw, init TLS ULP removes BPF proto hooks
The existing code did not expect users would initialize the TLS ULP
without subsequently calling the TLS TX enabling socket option.
If the application tries to send data after the TLS ULP enable op
but before the TLS TX enable op the BPF sk_msg verdict program is
skipped. This patch resolves this by converting the ipv4 sock ops
to be calculated at init time the same way ipv6 ops are done. This
pulls in any changes to the sock ops structure that have been made
after the socket was created including the changes from adding the
socket to a sock{map|hash}.

This was discovered by running OpenSSL master branch which calls
the TLS ULP setsockopt early in TLS handshake but only enables
the TLS TX path once the handshake has completed. As a result the
datapath missed the initial handshake messages.

Fixes: 02c558b2d5 ("bpf: sockmap, support for msg_peek in sk_msg with redirect ingress")
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-12-20 23:47:09 +01:00
John Fastabend
0608c69c9a bpf: sk_msg, sock{map|hash} redirect through ULP
A sockmap program that redirects through a kTLS ULP enabled socket
will not work correctly because the ULP layer is skipped. This
fixes the behavior to call through the ULP layer on redirect to
ensure any operations required on the data stream at the ULP layer
continue to be applied.

To do this we add an internal flag MSG_SENDPAGE_NOPOLICY to avoid
calling the BPF layer on a redirected message. This is
required to avoid calling the BPF layer multiple times (possibly
recursively) which is not the current/expected behavior without
ULPs. In the future we may add a redirect flag if users _do_
want the policy applied again but this would need to work for both
ULP and non-ULP sockets and be opt-in to avoid breaking existing
programs.

Also to avoid polluting the flag space with an internal flag we
reuse the flag space overlapping MSG_SENDPAGE_NOPOLICY with
MSG_WAITFORONE. Here WAITFORONE is specific to recv path and
SENDPAGE_NOPOLICY is only used for sendpage hooks. The last thing
to verify is user space API is masked correctly to ensure the flag
can not be set by user. (Note this needs to be true regardless
because we have internal flags already in-use that user space
should not be able to set). But for completeness we have two UAPI
paths into sendpage, sendfile and splice.

In the sendfile case the function do_sendfile() zero's flags,

./fs/read_write.c:
 static ssize_t do_sendfile(int out_fd, int in_fd, loff_t *ppos,
		   	    size_t count, loff_t max)
 {
   ...
   fl = 0;
#if 0
   /*
    * We need to debate whether we can enable this or not. The
    * man page documents EAGAIN return for the output at least,
    * and the application is arguably buggy if it doesn't expect
    * EAGAIN on a non-blocking file descriptor.
    */
    if (in.file->f_flags & O_NONBLOCK)
	fl = SPLICE_F_NONBLOCK;
#endif
    file_start_write(out.file);
    retval = do_splice_direct(in.file, &pos, out.file, &out_pos, count, fl);
 }

In the splice case the pipe_to_sendpage "actor" is used which
masks flags with SPLICE_F_MORE.

./fs/splice.c:
 static int pipe_to_sendpage(struct pipe_inode_info *pipe,
			    struct pipe_buffer *buf, struct splice_desc *sd)
 {
   ...
   more = (sd->flags & SPLICE_F_MORE) ? MSG_MORE : 0;
   ...
 }

Confirming what we expect that internal flags  are in fact internal
to socket side.

Fixes: d3b18ad31f ("tls: add bpf support to sk_msg handling")
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-12-20 23:47:09 +01:00
David S. Miller
2be09de7d6 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Lots of conflicts, by happily all cases of overlapping
changes, parallel adds, things of that nature.

Thanks to Stephen Rothwell, Saeed Mahameed, and others
for their guidance in these resolutions.

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-12-20 11:53:36 -08:00
Ganesh Goudar
c6ec179a00 net/tls: allocate tls context using GFP_ATOMIC
create_ctx can be called from atomic context, hence use
GFP_ATOMIC instead of GFP_KERNEL.

[  395.962599] BUG: sleeping function called from invalid context at mm/slab.h:421
[  395.979896] in_atomic(): 1, irqs_disabled(): 0, pid: 16254, name: openssl
[  395.996564] 2 locks held by openssl/16254:
[  396.010492]  #0: 00000000347acb52 (sk_lock-AF_INET){+.+.}, at: do_tcp_setsockopt.isra.44+0x13b/0x9a0
[  396.029838]  #1: 000000006c9552b5 (device_spinlock){+...}, at: tls_init+0x1d/0x280
[  396.047675] CPU: 5 PID: 16254 Comm: openssl Tainted: G           O      4.20.0-rc6+ #25
[  396.066019] Hardware name: Supermicro X10SRA-F/X10SRA-F, BIOS 2.0c 09/25/2017
[  396.083537] Call Trace:
[  396.096265]  dump_stack+0x5e/0x8b
[  396.109876]  ___might_sleep+0x216/0x250
[  396.123940]  kmem_cache_alloc_trace+0x1b0/0x240
[  396.138800]  create_ctx+0x1f/0x60
[  396.152504]  tls_init+0xbd/0x280
[  396.166135]  tcp_set_ulp+0x191/0x2d0
[  396.180035]  ? tcp_set_ulp+0x2c/0x2d0
[  396.193960]  do_tcp_setsockopt.isra.44+0x148/0x9a0
[  396.209013]  __sys_setsockopt+0x7c/0xe0
[  396.223054]  __x64_sys_setsockopt+0x20/0x30
[  396.237378]  do_syscall_64+0x4a/0x180
[  396.251200]  entry_SYSCALL_64_after_hwframe+0x49/0xbe

Fixes: df9d4a1780 ("net/tls: sleeping function from invalid context")
Signed-off-by: Ganesh Goudar <ganeshgr@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-12-19 16:28:50 -08:00
Atul Gupta
df9d4a1780 net/tls: sleeping function from invalid context
HW unhash within mutex for registered tls devices cause sleep
when called from tcp_set_state for TCP_CLOSE. Release lock and
re-acquire after function call with ref count incr/dec.
defined kref and fp release for tls_device to ensure device
is not released outside lock.

BUG: sleeping function called from invalid context at
kernel/locking/mutex.c:748
in_atomic(): 1, irqs_disabled(): 0, pid: 0, name: swapper/7
INFO: lockdep is turned off.
CPU: 7 PID: 0 Comm: swapper/7 Tainted: G        W  O
Call Trace:
 <IRQ>
 dump_stack+0x5e/0x8b
 ___might_sleep+0x222/0x260
 __mutex_lock+0x5c/0xa50
 ? vprintk_emit+0x1f3/0x440
 ? kmem_cache_free+0x22d/0x2a0
 ? tls_hw_unhash+0x2f/0x80
 ? printk+0x52/0x6e
 ? tls_hw_unhash+0x2f/0x80
 tls_hw_unhash+0x2f/0x80
 tcp_set_state+0x5f/0x180
 tcp_done+0x2e/0xe0
 tcp_rcv_state_process+0x92c/0xdd3
 ? lock_acquire+0xf5/0x1f0
 ? tcp_v4_rcv+0xa7c/0xbe0
 ? tcp_v4_do_rcv+0x70/0x1e0

Signed-off-by: Atul Gupta <atul.gupta@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-12-14 13:39:39 -08:00
Atul Gupta
6c0563e442 net/tls: Init routines in create_ctx
create_ctx is called from tls_init and tls_hw_prot
hence initialize function pointers in common routine.

Signed-off-by: Atul Gupta <atul.gupta@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-12-14 13:39:39 -08:00
John Fastabend
7246d8ed4d bpf: helper to pop data from messages
This adds a BPF SK_MSG program helper so that we can pop data from a
msg. We use this to pop metadata from a previous push data call.

Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-11-28 22:07:57 +01:00
Linus Torvalds
9931a07d51 Merge branch 'work.afs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull AFS updates from Al Viro:
 "AFS series, with some iov_iter bits included"

* 'work.afs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (26 commits)
  missing bits of "iov_iter: Separate type from direction and use accessor functions"
  afs: Probe multiple fileservers simultaneously
  afs: Fix callback handling
  afs: Eliminate the address pointer from the address list cursor
  afs: Allow dumping of server cursor on operation failure
  afs: Implement YFS support in the fs client
  afs: Expand data structure fields to support YFS
  afs: Get the target vnode in afs_rmdir() and get a callback on it
  afs: Calc callback expiry in op reply delivery
  afs: Fix FS.FetchStatus delivery from updating wrong vnode
  afs: Implement the YFS cache manager service
  afs: Remove callback details from afs_callback_break struct
  afs: Commit the status on a new file/dir/symlink
  afs: Increase to 64-bit volume ID and 96-bit vnode ID for YFS
  afs: Don't invoke the server to read data beyond EOF
  afs: Add a couple of tracepoints to log I/O errors
  afs: Handle EIO from delivery function
  afs: Fix TTL on VL server and address lists
  afs: Implement VL server rotation
  afs: Improve FS server rotation error handling
  ...
2018-11-01 19:58:52 -07:00
David Howells
aa563d7bca iov_iter: Separate type from direction and use accessor functions
In the iov_iter struct, separate the iterator type from the iterator
direction and use accessor functions to access them in most places.

Convert a bunch of places to use switch-statements to access them rather
then chains of bitwise-AND statements.  This makes it easier to add further
iterator types.  Also, this can be more efficient as to implement a switch
of small contiguous integers, the compiler can use ~50% fewer compare
instructions than it has to use bitwise-and instructions.

Further, cease passing the iterator type into the iterator setup function.
The iterator function can set that itself.  Only the direction is required.

Signed-off-by: David Howells <dhowells@redhat.com>
2018-10-24 00:41:07 +01:00
David Howells
00e2370744 iov_iter: Use accessor function
Use accessor functions to access an iterator's type and direction.  This
allows for the possibility of using some other method of determining the
type of iterator than if-chains with bitwise-AND conditions.

Signed-off-by: David Howells <dhowells@redhat.com>
2018-10-24 00:40:44 +01:00
Daniel Borkmann
c16ee04c9b ulp: remove uid and user_visible members
They are not used anymore and therefore should be removed.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-10-20 23:13:32 -07:00
John Fastabend
02c558b2d5 bpf: sockmap, support for msg_peek in sk_msg with redirect ingress
This adds support for the MSG_PEEK flag when doing redirect to ingress
and receiving on the sk_msg psock queue. Previously the flag was
being ignored which could confuse applications if they expected the
flag to work as normal.

Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-17 02:30:32 +02:00
John Fastabend
d3b18ad31f tls: add bpf support to sk_msg handling
This work adds BPF sk_msg verdict program support to kTLS
allowing BPF and kTLS to be combined together. Previously kTLS
and sk_msg verdict programs were mutually exclusive in the
ULP layer which created challenges for the orchestrator when
trying to apply TCP based policy, for example. To resolve this,
leveraging the work from previous patches that consolidates
the use of sk_msg, we can finally enable BPF sk_msg verdict
programs so they continue to run after the kTLS socket is
created. No change in behavior when kTLS is not used in
combination with BPF, the kselftest suite for kTLS also runs
successfully.

Joint work with Daniel.

Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-10-15 12:23:19 -07:00
John Fastabend
924ad65ed0 tls: replace poll implementation with read hook
Instead of re-implementing poll routine use the poll callback to
trigger read from kTLS, we reuse the stream_memory_read callback
which is simpler and achieves the same. This helps to align sockmap
and kTLS so we can more easily embed BPF in kTLS.

Joint work with Daniel.

Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-10-15 12:23:19 -07:00
Daniel Borkmann
d829e9c411 tls: convert to generic sk_msg interface
Convert kTLS over to make use of sk_msg interface for plaintext and
encrypted scattergather data, so it reuses all the sk_msg helpers
and data structure which later on in a second step enables to glue
this to BPF.

This also allows to remove quite a bit of open coded helpers which
are covered by the sk_msg API. Recent changes in kTLs 80ece6a03a
("tls: Remove redundant vars from tls record structure") and
4e6d47206c ("tls: Add support for inplace records encryption")
changed the data path handling a bit; while we've kept the latter
optimization intact, we had to undo the former change to better
fit the sk_msg model, hence the sg_aead_in and sg_aead_out have
been brought back and are linked into the sk_msg sgs. Now the kTLS
record contains a msg_plaintext and msg_encrypted sk_msg each.

In the original code, the zerocopy_from_iter() has been used out
of TX but also RX path. For the strparser skb-based RX path,
we've left the zerocopy_from_iter() in decrypt_internal() mostly
untouched, meaning it has been moved into tls_setup_from_iter()
with charging logic removed (as not used from RX). Given RX path
is not based on sk_msg objects, we haven't pursued setting up a
dummy sk_msg to call into sk_msg_zerocopy_from_iter(), but it
could be an option to prusue in a later step.

Joint work with John.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-10-15 12:23:19 -07:00
Vakul Garg
4e6d47206c tls: Add support for inplace records encryption
Presently, for non-zero copy case, separate pages are allocated for
storing plaintext and encrypted text of records. These pages are stored
in sg_plaintext_data and sg_encrypted_data scatterlists inside record
structure. Further, sg_plaintext_data & sg_encrypted_data are passed
to cryptoapis for record encryption. Allocating separate pages for
plaintext and encrypted text is inefficient from both required memory
and performance point of view.

This patch adds support of inplace encryption of records. For non-zero
copy case, we reuse the pages from sg_encrypted_data scatterlist to
copy the application's plaintext data. For the movement of pages from
sg_encrypted_data to sg_plaintext_data scatterlists, we introduce a new
function move_to_plaintext_sg(). This function add pages into
sg_plaintext_data from sg_encrypted_data scatterlists.

tls_do_encryption() is modified to pass the same scatterlist as both
source and destination into aead_request_set_crypt() if inplace crypto
has been enabled. A new ariable 'inplace_crypto' has been introduced in
record structure to signify whether the same scatterlist can be used.
By default, the inplace_crypto is enabled in get_rec(). If zero-copy is
used (i.e. plaintext data is not copied), inplace_crypto is set to '0'.

Signed-off-by: Vakul Garg <vakul.garg@nxp.com>
Reviewed-by: Dave Watson <davejwatson@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-02 23:03:47 -07:00
Vakul Garg
80ece6a03a tls: Remove redundant vars from tls record structure
Structure 'tls_rec' contains sg_aead_in and sg_aead_out which point
to a aad_space and then chain scatterlists sg_plaintext_data,
sg_encrypted_data respectively. Rather than using chained scatterlists
for plaintext and encrypted data in aead_req, it is efficient to store
aad_space in sg_encrypted_data and sg_plaintext_data itself in the
first index and get rid of sg_aead_in, sg_aead_in and further chaining.

This requires increasing size of sg_encrypted_data & sg_plaintext_data
arrarys by 1 to accommodate entry for aad_space. The code which uses
sg_encrypted_data and sg_plaintext_data has been modified to skip first
index as it points to aad_space.

Signed-off-by: Vakul Garg <vakul.garg@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-29 11:41:28 -07:00
Wei Yongjun
bf17b67198 net/tls: Make function get_rec() static
Fixes the following sparse warning:

net/tls/tls_sw.c:655:16: warning:
 symbol 'get_rec' was not declared. Should it be static?

Fixes: a42055e8d2 ("net/tls: Add support for async encryption of records for performance")
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-28 10:25:11 -07:00
Vakul Garg
c774973e91 tls: Fixed a memory leak during socket close
During socket close, if there is a open record with tx context, it needs
to be be freed apart from freeing up plaintext and encrypted scatter
lists. This patch frees up the open record if present in tx context.

Also tls_free_both_sg() has been renamed to tls_free_open_rec() to
indicate that the free record in tx context is being freed inside the
function.

Fixes: a42055e8d2 ("net/tls: Add support for async encryption")
Signed-off-by: Vakul Garg <vakul.garg@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-25 10:46:59 -07:00
Vakul Garg
b85135b595 tls: Fix socket mem accounting error under async encryption
Current async encryption implementation sometimes showed up socket
memory accounting error during socket close. This results in kernel
warning calltrace. The root cause of the problem is that socket var
sk_forward_alloc gets corrupted due to access in sk_mem_charge()
and sk_mem_uncharge() being invoked from multiple concurrent contexts
in multicore processor. The apis sk_mem_charge() and sk_mem_uncharge()
are called from functions alloc_plaintext_sg(), free_sg() etc. It is
required that memory accounting apis are called under a socket lock.

The plaintext sg data sent for encryption is freed using free_sg() in
tls_encryption_done(). It is wrong to call free_sg() from this function.
This is because this function may run in irq context. We cannot acquire
socket lock in this function.

We remove calling of function free_sg() for plaintext data from
tls_encryption_done() and defer freeing up of plaintext data to the time
when the record is picked up from tx_list and transmitted/freed. When
tls_tx_records() gets called, socket is already locked and thus there is
no concurrent access problem.

Fixes: a42055e8d2 ("net/tls: Add support for async encryption")
Signed-off-by: Vakul Garg <vakul.garg@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-25 10:43:01 -07:00
Vakul Garg
4128c0cfb1 tls: Fixed uninitialised vars warning
In tls_sw_sendmsg() and tls_sw_sendpage(), it is possible that the
uninitialised variable 'ret' gets passed to sk_stream_error(). So
initialise local variable 'ret' to '0. The warnings were detected by
'smatch' tool.

Fixes: a42055e8d2 ("net/tls: Add support for async encryption")
Signed-off-by: Vakul Garg <vakul.garg@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-24 12:24:52 -07:00
Vakul Garg
9932a29ab1 net/tls: Fixed race condition in async encryption
On processors with multi-engine crypto accelerators, it is possible that
multiple records get encrypted in parallel and their encryption
completion is notified to different cpus in multicore processor. This
leads to the situation where tls_encrypt_done() starts executing in
parallel on different cores. In current implementation, encrypted
records are queued to tx_ready_list in tls_encrypt_done(). This requires
addition to linked list 'tx_ready_list' to be protected. As
tls_decrypt_done() could be executing in irq content, it is not possible
to protect linked list addition operation using a lock.

To fix the problem, we remove linked list addition operation from the
irq context. We do tx_ready_list addition/removal operation from
application context only and get rid of possible multiple access to
the linked list. Before starting encryption on the record, we add it to
the tail of tx_ready_list. To prevent tls_tx_records() from transmitting
it, we mark the record with a new flag 'tx_ready' in 'struct tls_rec'.
When record encryption gets completed, tls_encrypt_done() has to only
update the 'tx_ready' flag to true & linked list add operation is not
required.

The changed logic brings some other side benefits. Since the records
are always submitted in tls sequence number order for encryption, the
tx_ready_list always remains sorted and addition of new records to it
does not have to traverse the linked list.

Lastly, we renamed tx_ready_list in 'struct tls_sw_context_tx' to
'tx_list'. This is because now, the some of the records at the tail are
not ready to transmit.

Fixes: a42055e8d2 ("net/tls: Add support for async encryption")
Signed-off-by: Vakul Garg <vakul.garg@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-24 12:24:24 -07:00
Vakul Garg
a42055e8d2 net/tls: Add support for async encryption of records for performance
In current implementation, tls records are encrypted & transmitted
serially. Till the time the previously submitted user data is encrypted,
the implementation waits and on finish starts transmitting the record.
This approach of encrypt-one record at a time is inefficient when
asynchronous crypto accelerators are used. For each record, there are
overheads of interrupts, driver softIRQ scheduling etc. Also the crypto
accelerator sits idle most of time while an encrypted record's pages are
handed over to tcp stack for transmission.

This patch enables encryption of multiple records in parallel when an
async capable crypto accelerator is present in system. This is achieved
by allowing the user space application to send more data using sendmsg()
even while previously issued data is being processed by crypto
accelerator. This requires returning the control back to user space
application after submitting encryption request to accelerator. This
also means that zero-copy mode of encryption cannot be used with async
accelerator as we must be done with user space application buffer before
returning from sendmsg().

There can be multiple records in flight to/from the accelerator. Each of
the record is represented by 'struct tls_rec'. This is used to store the
memory pages for the record.

After the records are encrypted, they are added in a linked list called
tx_ready_list which contains encrypted tls records sorted as per tls
sequence number. The records from tx_ready_list are transmitted using a
newly introduced function called tls_tx_records(). The tx_ready_list is
polled for any record ready to be transmitted in sendmsg(), sendpage()
after initiating encryption of new tls records. This achieves parallel
encryption and transmission of records when async accelerator is
present.

There could be situation when crypto accelerator completes encryption
later than polling of tx_ready_list by sendmsg()/sendpage(). Therefore
we need a deferred work context to be able to transmit records from
tx_ready_list. The deferred work context gets scheduled if applications
are not sending much data through the socket. If the applications issue
sendmsg()/sendpage() in quick succession, then the scheduling of
tx_work_handler gets cancelled as the tx_ready_list would be polled from
application's context itself. This saves scheduling overhead of deferred
work.

The patch also brings some side benefit. We are able to get rid of the
concept of CLOSED record. This is because the records once closed are
either encrypted and then placed into tx_ready_list or if encryption
fails, the socket error is set. This simplifies the kernel tls
sendpath. However since tls_device.c is still using macros, accessory
functions for CLOSED records have been retained.

Signed-off-by: Vakul Garg <vakul.garg@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-21 19:17:34 -07:00