tls_device_down takes a reference on all contexts it's going to move to
the degraded state (software fallback). If sk_destruct runs afterwards,
it can reduce the reference counter back to 1 and return early without
destroying the context. Then tls_device_down will release the reference
it took and call tls_device_free_ctx. However, the context will still
stay in tls_device_down_list forever. The list will contain an item,
memory for which is released, making a memory corruption possible.
Fix the above bug by properly removing the context from all lists before
any call to tls_device_free_ctx.
Fixes: 3740651bf7 ("tls: Fix context leak on tls_device_down")
Signed-off-by: Maxim Mikityanskiy <maximmi@nvidia.com>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Eric reports we should release the socket lock if the entire
"grab reader lock" operation has failed. The callers assume
they don't have to release it or otherwise unwind.
Reported-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot+16e72110feb2b653ef27@syzkaller.appspotmail.com
Fixes: 4cbc325ed6 ("tls: rx: allow only one reader at a time")
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20220720203701.2179034-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Socket destruction flow and tls_device_down function sync against each
other using tls_device_lock and the context refcount, to guarantee the
device resources are freed via tls_dev_del() by the end of
tls_device_down.
In the following unfortunate flow, this won't happen:
- refcount is decreased to zero in tls_device_sk_destruct.
- tls_device_down starts, skips the context as refcount is zero, going
all the way until it flushes the gc work, and returns without freeing
the device resources.
- only then, tls_device_queue_ctx_destruction is called, queues the gc
work and frees the context's device resources.
Solve it by decreasing the refcount in the socket's destruction flow
under the tls_device_lock, for perfect synchronization. This does not
slow down the common likely destructor flow, in which both the refcount
is decreased and the spinlock is acquired, anyway.
Fixes: e8f6979981 ("net/tls: Add generic NIC offload infrastructure")
Reviewed-by: Maxim Mikityanskiy <maximmi@nvidia.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
We currently CoW Rx skbs whenever we can't decrypt to a user
space buffer. The skbs can be enormous (64kB) and CoW does
a linear alloc which has a strong chance of failing under
memory pressure. Or even without, skb_cow_data() assumes
GFP_ATOMIC.
Allocate a new frag'd skb and decrypt into it. We finally
take advantage of the decrypted skb getting returned via
darg.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
The "zero-copy" path in SW TLS will engage either for no skbs or
for all but last. If the recvmsg parameters are right and the
socket can do ZC we'll ZC until the iterator can't fit a full
record at which point we'll decrypt one more record and copy
over the necessary bits to fill up the request.
The only reason we hold onto the ZC skbs which went thru the async
path until the end of recvmsg() is to count bytes. We need an accurate
count of zc'ed bytes so that we can calculate how much of the non-zc'd
data to copy. To allow freeing input skbs on the ZC path count only
how much of the list we'll need to consume.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Async crypto currently benefits from the fact that we decrypt
in place. When we allow input and output to be different skbs
we will have to hang onto the input while we move to the next
record. Clone the inputs and keep them on a list.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Async crypto TLS Rx currently waits for crypto to be done
in order to strip the TLS header and tailer. Simplify
the code by moving the pointers immediately, since only
TLS 1.2 is supported here there is no message padding.
This simplifies the decryption into a new skb in the next
patch as we don't have to worry about input vs output
skb in the decrypt_done() handler any more.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Instead of using ctx->recv_pkt after decryption read the skb
from darg.skb. This moves the decision of what the "output skb"
is to the decrypt handlers. For now after decrypt handler returns
successfully ctx->recv_pkt is simply moved to darg.skb, but it
will change soon.
Note that tls_decrypt_sg() cannot clear the ctx->recv_pkt
because it gets called to re-encrypt (i.e. by the device offload).
So we need an awkward temporary if() in tls_rx_one_record().
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Callers always pass ctx->recv_pkt into decrypt_skb_update(),
and it propagates it to its callees. This may give someone
the false impression that those functions can accept any valid
skb containing a TLS record. That's not the case, the record
sequence number is read from the context, and they can only
take the next record coming out of the strp.
Let the functions get the skb from the context instead of
passing it in. This will also make it cleaner to return
a different skb than ctx->recv_pkt as the decrypted one
later on.
Since we're touching the definition of decrypt_skb_update()
use this as an opportunity to rename it.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
I already forgot to transform darg from input to output
semantics once on the NIC inline crypto fastpath. To
avoid this happening again create a device equivalent
of decrypt_internal(). A function responsible for decryption
and transforming darg.
While at it rename decrypt_internal() to a hopefully slightly
more meaningful name.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
We no longer allow a decrypted skb to remain linked to ctx->recv_pkt.
Anything on the list is decrypted, anything on ctx->recv_pkt needs
to be decrypted.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Detach the skb from ctx->recv_pkt after decryption is done,
even if we can't consume it.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
I thought that having the skb either always on the ctx->rx_list
or ctx->recv_pkt will simplify the handling, as we would not
have to remember to flip it from one to the other on exit paths.
This became a little harder to justify with the fix for BPF
sockmaps. Subsequent changes will make the situation even worse.
Queue the skbs only when really needed.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
recvmsg() in TLS gets data from the skb list (rx_list) or fresh
skbs we read from TCP via strparser. The former holds skbs which were
already decrypted for peek or decrypted and partially consumed.
tls_wait_data() only notices appearance of fresh skbs coming out
of TCP (or psock). It is possible, if there is a concurrent call
to peek() and recv() that the peek() will move the data from input
to rx_list without recv() noticing. recv() will then read data out
of order or never wake up.
This is not a practical use case/concern, but it makes the self
tests less reliable. This patch solves the problem by allowing
only one reader in.
Because having multiple processes calling read()/peek() is not
normal avoid adding a lock and try to fast-path the single reader
case.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
As discussed with Maxim add a counter for true NoPad violations.
This should help deployments catch unexpected padded records vs
just control records which always need re-encryption.
https: //lore.kernel.org/all/b111828e6ac34baad9f4e783127eba8344ac252d.camel@nvidia.com/
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
tls_wait_data() sets the return code as an output parameter
and always returns ctx->recv_pkt on success.
Return the error code directly and let the caller read the skb
from the context. Use positive return code to indicate ctx->recv_pkt
is ready.
While touching the definition of the function rename it.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
include/net/tls.h is getting a little long, and is probably hard
for driver authors to navigate. Split out the internals into a
header which will live under net/tls/. While at it move some
static inlines with a single user into the source files, add
a few tls_ prefixes and fix spelling of 'proccess'.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The max size of iv + aad + tail is 22B. That's smaller
than a single sg entry (32B). Don't bother with the
memory packing, just create a struct which holds the
max size of those members.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
AAD size is either 5 or 13. Really no point complicating
the code for the 8B of difference. This will also let us
turn the chunked up buffer into a sane struct.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This reverts commit 284b4d93da.
When using TLS device offload and coming from tls_device_reencrypt()
flow, -EBADMSG error in tls_do_decryption() should not be counted
towards the TLSTlsDecryptError counter.
Move the counter increase back to the decrypt_internal() call site in
decrypt_skb_update().
This also fixes an issue where:
if (n_sgin < 1)
return -EBADMSG;
Errors in decrypt_internal() were not counted after the cited patch.
Fixes: 284b4d93da ("tls: rx: move counting TlsDecryptErrors for sync")
Cc: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Maxim Mikityanskiy <maximmi@nvidia.com>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Gal Pressman <gal@nvidia.com>
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
We continuously hold the socket lock during large reads and writes.
This may inflate RTT and negatively impact TCP performance.
Flush the backlog periodically. I tried to pick a flush period (128kB)
which gives significant benefit but the max Bps rate is not yet visibly
impacted.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Since optimisitic decrypt may add extra load in case of retries
require socket owner to explicitly opt-in.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
We currently don't support decrypt to user buffer with TLS 1.3
because we don't know the record type and how much padding
record contains before decryption. In practice data records
are by far most common and padding gets used rarely so
we can assume data record, no padding, and if we find out
that wasn't the case - retry the crypto in place (decrypt
to skb).
To safeguard from user overwriting content type and padding
before we can check it attach a 1B sg entry where last byte
of the record will land.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
To make future patches easier to review make data_len
contain the length of the data, without the tail.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Most drivers use "skb_transport_offset(skb) + tcp_hdrlen(skb)"
to compute headers length for a TCP packet, but others
use more convoluted (but equivalent) ways.
Add skb_tcp_all_headers() and skb_inner_tcp_all_headers()
helpers to harmonize this a bit.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit 8a59f9d1e3 ("sock: Introduce sk->sk_prot->psock_update_sk_prot()")
has moved the inet_csk_has_ulp(sk) check from sk_psock_init() to
the new tcp_bpf_update_proto() function. I'm guessing that this
was done to allow creating psocks for non-inet sockets.
Unfortunately the destruction path for psock includes the ULP
unwind, so we need to fail the sk_psock_init() itself.
Otherwise if ULP is already present we'll notice that later,
and call tcp_update_ulp() with the sk_proto of the ULP
itself, which will most likely result in the ULP looping
its callbacks.
Fixes: 8a59f9d1e3 ("sock: Introduce sk->sk_prot->psock_update_sk_prot()")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: John Fastabend <john.fastabend@gmail.com>
Reviewed-by: Jakub Sitnicki <jakub@cloudflare.com>
Tested-by: Jakub Sitnicki <jakub@cloudflare.com>
Link: https://lore.kernel.org/r/20220620191353.1184629-2-kuba@kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
This reverts commit 69135c572d.
This commit was just papering over the issue, ULP should not
get ->update() called with its own sk_prot. Each ULP would
need to add this check.
Fixes: 69135c572d ("net/tls: fix tls_sk_proto_close executed repeatedly")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/r/20220620191353.1184629-1-kuba@kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
After setting the sock ktls, update ctx->sk_proto to sock->sk_prot by
tls_update(), so now ctx->sk_proto->close is tls_sk_proto_close(). When
close the sock, tls_sk_proto_close() is called for sock->sk_prot->close
is tls_sk_proto_close(). But ctx->sk_proto->close() will be executed later
in tls_sk_proto_close(). Thus tls_sk_proto_close() executed repeatedly
occurred. That will trigger the following bug.
=================================================================
KASAN: null-ptr-deref in range [0x0000000000000010-0x0000000000000017]
RIP: 0010:tls_sk_proto_close+0xd8/0xaf0 net/tls/tls_main.c:306
Call Trace:
<TASK>
tls_sk_proto_close+0x356/0xaf0 net/tls/tls_main.c:329
inet_release+0x12e/0x280 net/ipv4/af_inet.c:428
__sock_release+0xcd/0x280 net/socket.c:650
sock_close+0x18/0x20 net/socket.c:1365
Updating a proto which is same with sock->sk_prot is incorrect. Add proto
and sock->sk_prot equality check at the head of tls_update() to fix it.
Fixes: 95fa145479 ("bpf: sockmap/tls, close can race with map free")
Reported-by: syzbot+29c3c12f3214b85ad081@syzkaller.appspotmail.com
Signed-off-by: Ziyang Xuan <william.xuanziyang@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
To embrace possible future optimizations of TLS, rename zerocopy
sendfile definitions to more generic ones:
* setsockopt: TLS_TX_ZEROCOPY_SENDFILE- > TLS_TX_ZEROCOPY_RO
* sock_diag: TLS_INFO_ZC_SENDFILE -> TLS_INFO_ZC_RO_TX
RO stands for readonly and emphasizes that the application shouldn't
modify the data being transmitted with zerocopy to avoid potential
disconnection.
Fixes: c1318b39c7 ("tls: Add opt-in zerocopy mode of sendfile()")
Signed-off-by: Maxim Mikityanskiy <maximmi@nvidia.com>
Link: https://lore.kernel.org/r/20220608153425.3151146-1-maximmi@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Artem points out that skb may try to take over the skb and
queue it to its own list. Unlink the skb before calling out.
Fixes: b1a2c17863 ("tls: rx: clear ctx->recv_pkt earlier")
Reported-by: Artem Savkov <asavkov@redhat.com>
Tested-by: Artem Savkov <asavkov@redhat.com>
Link: https://lore.kernel.org/r/20220518205644.2059468-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
TLS device offload copies sendfile data to a bounce buffer before
transmitting. It allows to maintain the valid MAC on TLS records when
the file contents change and a part of TLS record has to be
retransmitted on TCP level.
In many common use cases (like serving static files over HTTPS) the file
contents are not changed on the fly. In many use cases breaking the
connection is totally acceptable if the file is changed during
transmission, because it would be received corrupted in any case.
This commit allows to optimize performance for such use cases to
providing a new optional mode of TLS sendfile(), in which the extra copy
is skipped. Removing this copy improves performance significantly, as
TLS and TCP sendfile perform the same operations, and the only overhead
is TLS header/trailer insertion.
The new mode can only be enabled with the new socket option named
TLS_TX_ZEROCOPY_SENDFILE on per-socket basis. It preserves backwards
compatibility with existing applications that rely on the copying
behavior.
The new mode is safe, meaning that unsolicited modifications of the file
being sent can't break integrity of the kernel. The worst thing that can
happen is sending a corrupted TLS record, which is in any case not
forbidden when using regular TCP sockets.
Sockets other than TLS device offload are not affected by the new socket
option. The actual status of zerocopy sendfile can be queried with
sock_diag.
Performance numbers in a single-core test with 24 HTTPS streams on
nginx, under 100% CPU load:
* non-zerocopy: 33.6 Gbit/s
* zerocopy: 79.92 Gbit/s
CPU: Intel(R) Xeon(R) Platinum 8380 CPU @ 2.30GHz
Signed-off-by: Boris Pismenny <borisp@nvidia.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Maxim Mikityanskiy <maximmi@nvidia.com>
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Link: https://lore.kernel.org/r/20220518092731.1243494-1-maximmi@nvidia.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
The commit cited below claims to fix a use-after-free condition after
tls_device_down. Apparently, the description wasn't fully accurate. The
context stayed alive, but ctx->netdev became NULL, and the offload was
torn down without a proper fallback, so a bug was present, but a
different kind of bug.
Due to misunderstanding of the issue, the original patch dropped the
refcount_dec_and_test line for the context to avoid the alleged
premature deallocation. That line has to be restored, because it matches
the refcount_inc_not_zero from the same function, otherwise the contexts
that survived tls_device_down are leaked.
This patch fixes the described issue by restoring refcount_dec_and_test.
After this change, there is no leak anymore, and the fallback to
software kTLS still works.
Fixes: c55dcdd435 ("net/tls: Fix use-after-free after the TLS device goes down and up")
Signed-off-by: Maxim Mikityanskiy <maximmi@nvidia.com>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Link: https://lore.kernel.org/r/20220512091830.678684-1-maximmi@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Calling tls_append_frag when max_open_record_len == record->len might
add an empty fragment to the TLS record if the call happens to be on the
page boundary. Normally tls_append_frag coalesces the zero-sized
fragment to the previous one, but not if it's on page boundary.
If a resync happens then, the mlx5 driver posts dump WQEs in
tx_post_resync_dump, and the empty fragment may become a data segment
with byte_count == 0, which will confuse the NIC and lead to a CQE
error.
This commit fixes the described issue by skipping tls_append_frag on
zero size to avoid adding empty fragments. The fix is not in the driver,
because an empty fragment is hardly the desired behavior.
Fixes: e8f6979981 ("net/tls: Add generic NIC offload infrastructure")
Signed-off-by: Maxim Mikityanskiy <maximmi@nvidia.com>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Link: https://lore.kernel.org/r/20220426154949.159055-1-maximmi@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
When NIC takes care of crypto (or the record has already
been decrypted) we forget to update darg->async. ->async
is supposed to mean whether record is async capable on
input and whether record has been queued for async crypto
on output.
Reported-by: Gal Pressman <gal@nvidia.com>
Fixes: 3547a1f9d9 ("tls: rx: use async as an in-out argument")
Tested-by: Gal Pressman <gal@nvidia.com>
Link: https://lore.kernel.org/r/20220425233309.344858-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Logic added in commit f35f821935 ("tcp: defer skb freeing after socket
lock is released") helped bulk TCP flows to move the cost of skbs
frees outside of critical section where socket lock was held.
But for RPC traffic, or hosts with RFS enabled, the solution is far from
being ideal.
For RPC traffic, recvmsg() has to return to user space right after
skb payload has been consumed, meaning that BH handler has no chance
to pick the skb before recvmsg() thread. This issue is more visible
with BIG TCP, as more RPC fit one skb.
For RFS, even if BH handler picks the skbs, they are still picked
from the cpu on which user thread is running.
Ideally, it is better to free the skbs (and associated page frags)
on the cpu that originally allocated them.
This patch removes the per socket anchor (sk->defer_list) and
instead uses a per-cpu list, which will hold more skbs per round.
This new per-cpu list is drained at the end of net_action_rx(),
after incoming packets have been processed, to lower latencies.
In normal conditions, skbs are added to the per-cpu list with
no further action. In the (unlikely) cases where the cpu does not
run net_action_rx() handler fast enough, we use an IPI to raise
NET_RX_SOFTIRQ on the remote cpu.
Also, we do not bother draining the per-cpu list from dev_cpu_dead()
This is because skbs in this list have no requirement on how fast
they should be freed.
Note that we can add in the future a small per-cpu cache
if we see any contention on sd->defer_lock.
Tested on a pair of hosts with 100Gbit NIC, RFS enabled,
and /proc/sys/net/ipv4/tcp_rmem[2] tuned to 16MB to work around
page recycling strategy used by NIC driver (its page pool capacity
being too small compared to number of skbs/pages held in sockets
receive queues)
Note that this tuning was only done to demonstrate worse
conditions for skb freeing for this particular test.
These conditions can happen in more general production workload.
10 runs of one TCP_STREAM flow
Before:
Average throughput: 49685 Mbit.
Kernel profiles on cpu running user thread recvmsg() show high cost for
skb freeing related functions (*)
57.81% [kernel] [k] copy_user_enhanced_fast_string
(*) 12.87% [kernel] [k] skb_release_data
(*) 4.25% [kernel] [k] __free_one_page
(*) 3.57% [kernel] [k] __list_del_entry_valid
1.85% [kernel] [k] __netif_receive_skb_core
1.60% [kernel] [k] __skb_datagram_iter
(*) 1.59% [kernel] [k] free_unref_page_commit
(*) 1.16% [kernel] [k] __slab_free
1.16% [kernel] [k] _copy_to_iter
(*) 1.01% [kernel] [k] kfree
(*) 0.88% [kernel] [k] free_unref_page
0.57% [kernel] [k] ip6_rcv_core
0.55% [kernel] [k] ip6t_do_table
0.54% [kernel] [k] flush_smp_call_function_queue
(*) 0.54% [kernel] [k] free_pcppages_bulk
0.51% [kernel] [k] llist_reverse_order
0.38% [kernel] [k] process_backlog
(*) 0.38% [kernel] [k] free_pcp_prepare
0.37% [kernel] [k] tcp_recvmsg_locked
(*) 0.37% [kernel] [k] __list_add_valid
0.34% [kernel] [k] sock_rfree
0.34% [kernel] [k] _raw_spin_lock_irq
(*) 0.33% [kernel] [k] __page_cache_release
0.33% [kernel] [k] tcp_v6_rcv
(*) 0.33% [kernel] [k] __put_page
(*) 0.29% [kernel] [k] __mod_zone_page_state
0.27% [kernel] [k] _raw_spin_lock
After patch:
Average throughput: 73076 Mbit.
Kernel profiles on cpu running user thread recvmsg() looks better:
81.35% [kernel] [k] copy_user_enhanced_fast_string
1.95% [kernel] [k] _copy_to_iter
1.95% [kernel] [k] __skb_datagram_iter
1.27% [kernel] [k] __netif_receive_skb_core
1.03% [kernel] [k] ip6t_do_table
0.60% [kernel] [k] sock_rfree
0.50% [kernel] [k] tcp_v6_rcv
0.47% [kernel] [k] ip6_rcv_core
0.45% [kernel] [k] read_tsc
0.44% [kernel] [k] _raw_spin_lock_irqsave
0.37% [kernel] [k] _raw_spin_lock
0.37% [kernel] [k] native_irq_return_iret
0.33% [kernel] [k] __inet6_lookup_established
0.31% [kernel] [k] ip6_protocol_deliver_rcu
0.29% [kernel] [k] tcp_rcv_established
0.29% [kernel] [k] llist_reverse_order
v2: kdoc issue (kernel bots)
do not defer if (alloc_cpu == smp_processor_id()) (Paolo)
replace the sk_buff_head with a single-linked list (Jakub)
add a READ_ONCE()/WRITE_ONCE() for the lockless read of sd->defer_list
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Link: https://lore.kernel.org/r/20220422201237.416238-1-eric.dumazet@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
TLS 1.3 and ChaChaPoly don't carry IV in the packet.
The code before this change would copy out iv_size
worth of whatever followed the TLS header in the packet
and then for TLS 1.3 | ChaCha overwrite that with
the sequence number. Waste of cycles especially
with TLS 1.2 being close to dead and TLS 1.3 being
the common case.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
IVs are 8 or 16 bytes, no point reading out the exact value
for quantities this small.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Propagating EINPROGRESS thru multiple layers of functions is
error prone. Use darg->async as an in/out argument, like we
use darg->zc today. On input it tells the code if async is
allowed, on output if it took place.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
async crypto handler will report the socket error no need
to report it again. We can, however, let the data we already
copied be reported to user space but we need to make sure
the error will be reported next time around.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
process_rx_list() only fails if it can't copy data to user
space. There is no point recording the error onto sk->sk_err
or giving up on the data which was read partially. Treat
the return value like a normal socket partial read.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
If crypto didn't always invoke our callback for async
we'd not be clearing skb->sk and would crash in the
skb core when freeing it. This if must be dead code.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Async crypto never worked with TLS 1.3 and was explicitly disabled in
commit 8497ded2d1 ("net/tls: Disable async decrytion for tls1.3").
There's no need for us to handle TLS 1.3 padding in the async cb.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Move counting TlsDecryptErrors to tls_do_decryption()
where differences between sync and async crypto are
reconciled.
No functional changes, this code just always gave
me a pause.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
rx_list is protected by the socket lock, no need to take
the built-in spin lock on accesses.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
The internal recvmsg() functions have two parameters 'flags' and 'noblock'
that were merged inside skb_recv_datagram(). As a follow up patch to commit
f4b41f062c ("net: remove noblock parameter from skb_recv_datagram()")
this patch removes the separate 'noblock' parameter for recvmsg().
Analogue to the referenced patch for skb_recv_datagram() the 'flags' and
'noblock' parameters are unnecessarily split up with e.g.
err = sk->sk_prot->recvmsg(sk, msg, size, flags & MSG_DONTWAIT,
flags & ~MSG_DONTWAIT, &addr_len);
or in
err = INDIRECT_CALL_2(sk->sk_prot->recvmsg, tcp_recvmsg, udp_recvmsg,
sk, msg, size, flags & MSG_DONTWAIT,
flags & ~MSG_DONTWAIT, &addr_len);
instead of simply using only flags all the time and check for MSG_DONTWAIT
where needed (to preserve for the formerly separated no(n)block condition).
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://lore.kernel.org/r/20220411124955.154876-1-socketcan@hartkopp.net
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
The current invese logic is harder to follow (and adds extra
tests to the fast path). We have to enumerate all cases which
need to keep the skb before consuming it. It's simpler to
jump out of the full record flow as we detect those cases.
This makes it clear that partial consumption and peek can
only reach end of the function thru the !zc case so move
the code up there.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Whatever we do in the loop the skb should not remain on as
ctx->recv_pkt afterwards. We can clear that pointer and
restart strparser earlier.
This adds overhead of extra linking and unlinking to rx_list
but that's not large (upcoming change will switch to unlocked
skb list operations).
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
tls_sw_advance_skb() always consumes the skb at the end of the loop.
To fall here the following must be true:
!async && !is_peek && !retain_skb
retain_skb => !zc && rxm->full_len > len
# but non-full record implies !zc, so above can be simplified as
retain_skb => rxm->full_len > len
!async && !is_peek && !(rxm->full_len > len)
!async && !is_peek && rxm->full_len <= len
tls_sw_advance_skb() returns false if len < rxm->full_len
which can't be true given conditions above.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Most of the conditions deciding if zero-copy can be used
do not change throughout the iterations, so pre-calculate
them.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
We track both if the last record was handled by async crypto
and how many records were async. This is not necessary. We
implicitly assume once crypto goes async it will stay that
way, otherwise we'd reorder records. So just track if we're
in async mode, the exact number of records is not necessary.
This change also forces us into "async" mode more consistently
in case crypto ever decided to interleave async and sync.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
tls_sw_advance_skb() caters to the async case when skb argument
is NULL. In that case it simply unpauses the strparser.
These are surprising semantics to a person reading the code,
and result in higher LoC, so inline the __strp_unpause and
only call tls_sw_advance_skb() when we actually move past
an skb.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
cmsg can be filled in during rx_list processing or normal
receive. Consolidate the code.
We don't need to keep the boolean to track if the cmsg was
created. 0 is an invalid content type.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Since we are protected from async completions by decrypt_compl_lock
we can drop the async_notify and reinit the completion before we
start waiting.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
We pass zc as a pointer to bool a few functions down as an in/out
argument. This is error prone since C will happily evalue a pointer
as a boolean (IOW forgetting *zc and writing zc leads to loss of
developer time..). Wrap the arguments into a structure.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
We plumb pointer to chunk all the way to the decryption method.
It's set to the length of the text when decrypt_skb_update()
returns.
I think the code is written this way because original TLS
implementation passed &chunk to zerocopy_from_iter() and this
was carried forward as the code gotten more complex, without
any refactoring.
The fix for peek() introduced a new variable - to_decrypt
which for all practical purposes is what chunk is going to
get set to. Spare ourselves the pointer passing, use to_decrypt.
Use this opportunity to clean things up a little further.
Note that chunk / to_decrypt was mostly needed for the async
path, since the sync path would access rxm->full_len (decryption
transforms full_len from record size to text size). Use the
right source of truth more explicitly.
We have three cases:
- async - it's TLS 1.2 only, so chunk == to_decrypt, but we
need the min() because to_decrypt is a whole record
and we don't want to underflow len. Note that we can't
handle partial record by falling back to sync as it
would introduce reordering against records in flight.
- zc - again, TLS 1.2 only for now, so chunk == to_decrypt,
we don't do zc if len < to_decrypt, no need to check again.
- normal - it already handles chunk > len, we can factor out the
assignment to rxm->full_len and share it with zc.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
sk is unused, remove it to make it clear the function
doesn't poke at the socket.
size_used is always 0 on input and @length on success.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Instead of tls_device poking into internals of the message
return 1 from tls_device_decrypted() if the device handled
the decryption.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Use early return and a jump label to remove two indentation levels.
No functional changes.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
We inform the applications that data is available when
the record is received. Decryption happens inline inside
recvmsg or splice call. Generating another wakeup inside
the decryption handler seems pointless as someone must
be actively reading the socket if we are executing this
code.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
The padding length TLS 1.3 logic is searching for content_type from
the end of text. IMHO the code is easier to parse if we calculate
offset and decrement it rather than try to maintain positive offset
from the end of the record called "back".
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
TLS 1.3 has to strip padding, and it starts out 16 bytes
from the end of the record. Make it clear this is because
of the auth tag.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
We set the record type in tls_read_size(), can as well init
the tlm->decrypted field there.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Similar justification to previous change, the information
about decryption status belongs in the skb.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Original TLS implementation was handling one record at a time.
It stashed the type of the record inside tls context (per socket
structure) for convenience. When async crypto support was added
[1] the author had to use skb->cb to store the type per-message.
The use of skb->cb overlaps with strparser, however, so a hybrid
approach was taken where type is stored in context while parsing
(since we parse a message at a time) but once parsed its copied
to skb->cb.
Recently a workaround for sockmaps [2] exposed the previously
private struct _strp_msg and started a trend of adding user
fields directly in strparser's header. This is cleaner than
storing information about an skb in the context.
This change is not strictly necessary, but IMHO the ownership
of the context field is confusing. Information naturally
belongs to the skb.
[1] commit 94524d8fc9 ("net/tls: Add support for async decryption of tls records")
[2] commit b2c4618162 ("bpf, sockmap: sk_skb data_end access incorrect when src_reg = dst_reg")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pointless else branch after goto makes the code harder to refactor
down the line.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
'recv_end:' checks num_async and decrypted, and is then followed
by the 'end' label. Since we know that decrypted and num_async
are 0 at the start we can jump to 'end'.
Move the init of decrypted and num_async to let the compiler
catch if I'm wrong.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
The memory size of tls_ctx->rx.iv for AES128-CCM is 12 setting in
tls_set_sw_offload(). The return value of crypto_aead_ivsize()
for "ccm(aes)" is 16. So memcpy() require 16 bytes from 12 bytes
memory space will trigger slab-out-of-bounds bug as following:
==================================================================
BUG: KASAN: slab-out-of-bounds in decrypt_internal+0x385/0xc40 [tls]
Read of size 16 at addr ffff888114e84e60 by task tls/10911
Call Trace:
<TASK>
dump_stack_lvl+0x34/0x44
print_report.cold+0x5e/0x5db
? decrypt_internal+0x385/0xc40 [tls]
kasan_report+0xab/0x120
? decrypt_internal+0x385/0xc40 [tls]
kasan_check_range+0xf9/0x1e0
memcpy+0x20/0x60
decrypt_internal+0x385/0xc40 [tls]
? tls_get_rec+0x2e0/0x2e0 [tls]
? process_rx_list+0x1a5/0x420 [tls]
? tls_setup_from_iter.constprop.0+0x2e0/0x2e0 [tls]
decrypt_skb_update+0x9d/0x400 [tls]
tls_sw_recvmsg+0x3c8/0xb50 [tls]
Allocated by task 10911:
kasan_save_stack+0x1e/0x40
__kasan_kmalloc+0x81/0xa0
tls_set_sw_offload+0x2eb/0xa20 [tls]
tls_setsockopt+0x68c/0x700 [tls]
__sys_setsockopt+0xfe/0x1b0
Replace the crypto_aead_ivsize() with prot->iv_size + prot->salt_size
when memcpy() iv value in TLS_1_3_VERSION scenario.
Fixes: f295b3ae9f ("net/tls: Add support of AES128-CCM based ciphers")
Signed-off-by: Ziyang Xuan <william.xuanziyang@huawei.com>
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
It is known that priority setting HW offload when set tls TX/RX offload
by setsockopt(). Check netdevice whether support NETIF_F_HW_TLS_TX or
not at the later stages in the whole tls_set_device_offload() process,
some memory allocations have been done before that. We must release those
memory and return error if we judge the netdevice not support
NETIF_F_HW_TLS_TX. It is redundant.
Move NETIF_F_HW_TLS_TX judgement forward, and move start_marker_record
and offload_ctx memory allocation back slightly. Thus, we can get
simpler exception handling process.
Signed-off-by: Ziyang Xuan <william.xuanziyang@huawei.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Avoid using "goto" jump instruction unconditionally when we
can return directly. Remove unnecessary jump instructions in
do_tls_setsockopt_conf().
Signed-off-by: Ziyang Xuan <william.xuanziyang@huawei.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
TLS recvmsg() passes user pages as destination for decrypt.
The decrypt operation is repeated record by record, each
record being 16kB, max. TLS allocates an sg_table and uses
iov_iter_get_pages() to populate it with enough pages to
fit the decrypted record.
Even though we decrypt a single message at a time we size
the sg_table based on the entire length of the iovec.
This leads to unnecessarily large allocations, risking
triggering OOM conditions.
Use iov_iter_truncate() / iov_iter_reexpand() to construct
a "capped" version of iov_iter_npages(). Alternatively we
could parametrize iov_iter_npages() to take the size as
arg instead of using i->count, or do something else..
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch is a followup to
commit ffef737fd0 ("net/tls: Fix skb memory leak when running kTLS traffic")
Which was missing another sk_defer_free_flush() call in
tls_sw_splice_read().
Fixes: f35f821935 ("tcp: defer skb freeing after socket lock is released")
Signed-off-by: Gal Pressman <gal@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The cited Fixes commit introduced a memory leak when running kTLS
traffic (with/without hardware offloads).
I'm running nginx on the server side and wrk on the client side and get
the following:
unreferenced object 0xffff8881935e9b80 (size 224):
comm "softirq", pid 0, jiffies 4294903611 (age 43.204s)
hex dump (first 32 bytes):
80 9b d0 36 81 88 ff ff 00 00 00 00 00 00 00 00 ...6............
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace:
[<00000000efe2a999>] build_skb+0x1f/0x170
[<00000000ef521785>] mlx5e_skb_from_cqe_mpwrq_linear+0x2bc/0x610 [mlx5_core]
[<00000000945d0ffe>] mlx5e_handle_rx_cqe_mpwrq+0x264/0x9e0 [mlx5_core]
[<00000000cb675b06>] mlx5e_poll_rx_cq+0x3ad/0x17a0 [mlx5_core]
[<0000000018aac6a9>] mlx5e_napi_poll+0x28c/0x1b60 [mlx5_core]
[<000000001f3369d1>] __napi_poll+0x9f/0x560
[<00000000cfa11f72>] net_rx_action+0x357/0xa60
[<000000008653b8d7>] __do_softirq+0x282/0x94e
[<00000000644923c6>] __irq_exit_rcu+0x11f/0x170
[<00000000d4085f8f>] irq_exit_rcu+0xa/0x20
[<00000000d412fef4>] common_interrupt+0x7d/0xa0
[<00000000bfb0cebc>] asm_common_interrupt+0x1e/0x40
[<00000000d80d0890>] default_idle+0x53/0x70
[<00000000f2b9780e>] default_idle_call+0x8c/0xd0
[<00000000c7659e15>] do_idle+0x394/0x450
I'm not familiar with these areas of the code, but I've added this
sk_defer_free_flush() to tls_sw_recvmsg() based on a hunch and it
resolved the issue.
Fixes: f35f821935 ("tcp: defer skb freeing after socket lock is released")
Signed-off-by: Gal Pressman <gal@nvidia.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20220102081253.9123-1-gal@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Assigning crypto_info variables in advance can simplify the logic
of accessing value and move related local variables to a smaller
scope.
Signed-off-by: Tianjia Zhang <tianjia.zhang@linux.alibaba.com>
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
When the TLS cipher suite uses CCM mode, including AES CCM and
SM4 CCM, the first byte of the B0 block is flags, and the real
IV starts from the second byte. The XOR operation of the IV and
rec_seq should be skip this byte, that is, add the iv_offset.
Fixes: f295b3ae9f ("net/tls: Add support of AES128-CCM based ciphers")
Signed-off-by: Tianjia Zhang <tianjia.zhang@linux.alibaba.com>
Cc: Vakul Garg <vakul.garg@nxp.com>
Cc: stable@vger.kernel.org # v5.2+
Signed-off-by: David S. Miller <davem@davemloft.net>
We replace proto_ops whenever TLS is configured for RX. But our
replacement also overrides sendpage_locked, which will crash
unless TX is also configured. Similarly we plug both of those
in for TLS_HW (NIC crypto offload) even tho TLS_HW has a completely
different implementation for TX.
Last but not least we always plug in something based on inet_stream_ops
even though a few of the callbacks differ for IPv6 (getname, release,
bind).
Use a callback building method similar to what we do for struct proto.
Fixes: c46234ebb4 ("tls: RX path for ktls")
Fixes: d4ffb02dee ("net/tls: enable sk_msg redirect to tls socket egress")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
recvmsg() will put peek()ed and partially read records onto the rx_list.
splice_read() needs to consult that list otherwise it may miss data.
Align with recvmsg() and also put partially-read records onto rx_list.
tls_sw_advance_skb() is pretty pointless now and will be removed in
net-next.
Fixes: 692d7b5d1f ("tls: Fix recvmsg() to be able to peek across multiple records")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
We don't support splicing control records. TLS 1.3 changes moved
the record type check into the decrypt if(). The skb may already
be decrypted and still be an alert.
Note that decrypt_skb_update() is idempotent and updates ctx->decrypted
so the if() is pointless.
Reorder the check for decryption errors with the content type check
while touching them. This part is not really a bug, because if
decryption failed in TLS 1.3 content type will be DATA, and for
TLS 1.2 it will be correct. Nevertheless its strange to touch output
before checking if the function has failed.
Fixes: fedf201e12 ("net: tls: Refactor control message handling on recv")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
sk->sk_err contains a positive number, yet async_wait.err wants the
opposite. Fix the missed sign flip, which Jakub caught by inspection.
Fixes: a42055e8d2 ("net/tls: Add support for async encryption of records for performance")
Suggested-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
sk->sk_err appears to expect a positive value, a convention that ktls
doesn't always follow and that leads to memory corruption in other code.
For instance,
[kworker]
tls_encrypt_done(..., err=<negative error from crypto request>)
tls_err_abort(.., err)
sk->sk_err = err;
[task]
splice_from_pipe_feed
...
tls_sw_do_sendpage
if (sk->sk_err) {
ret = -sk->sk_err; // ret is positive
splice_from_pipe_feed (continued)
ret = actor(...) // ret is still positive and interpreted as bytes
// written, resulting in underflow of buf->len and
// sd->len, leading to huge buf->offset and bogus
// addresses computed in later calls to actor()
Fix all tls_err_abort() callers to pass a negative error code
consistently and centralize the error-prone sign flip there, throwing in
a warning to catch future misuse and uninlining the function so it
really does only warn once.
Cc: stable@vger.kernel.org
Fixes: c46234ebb4 ("tls: RX path for ktls")
Reported-by: syzbot+b187b77c8474f9648fae@syzkaller.appspotmail.com
Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The proto ops ->stream_memory_read() is currently only used
by TCP to check whether psock queue is empty or not. We need
to rename it before reusing it for non-TCP protocols, and
adjust the exsiting users accordingly.
Signed-off-by: Cong Wang <cong.wang@bytedance.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211008203306.37525-2-xiyou.wangcong@gmail.com
AES_CCM_128 and CHACHA20_POLY1305 are already supported by tls,
similar to setsockopt, getsockopt also needs to support these
two algorithms.
Signed-off-by: Tianjia Zhang <tianjia.zhang@linux.alibaba.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The IV of CCM mode has special requirements, this patch supports CCM
mode of SM4 algorithm.
Signed-off-by: Tianjia Zhang <tianjia.zhang@linux.alibaba.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The RFC8998 specification defines the use of the ShangMi algorithm
cipher suites in TLS 1.3, and also supports the GCM/CCM mode using
the SM4 algorithm.
Signed-off-by: Tianjia Zhang <tianjia.zhang@linux.alibaba.com>
Acked-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Trivial conflict in net/netfilter/nf_tables_api.c.
Duplicate fix in tools/testing/selftests/net/devlink_port_split.py
- take the net-next version.
skmsg, and L4 bpf - keep the bpf code but remove the flags
and err params.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
We got multiple reports that multi_chunk_sendfile test
case from tls selftest fails. This was sort of expected,
as the original fix was never applied (see it in the first
Link:). The test in question uses sendfile() with count
larger than the size of the underlying file. This will
make splice set MSG_MORE on all sendpage calls, meaning
TLS will never close and flush the last partial record.
Eric seem to have addressed a similar problem in
commit 35f9c09fe9 ("tcp: tcp_sendpages() should call tcp_push() once")
by introducing MSG_SENDPAGE_NOTLAST. Unlike MSG_MORE
MSG_SENDPAGE_NOTLAST is not set on the last call
of a "pipefull" of data (PIPE_DEF_BUFFERS == 16,
so every 16 pages or whenever we run out of data).
Having a break every 16 pages should be fine, TLS
can pack exactly 4 pages into a record, so for
aligned reads there should be no difference,
unaligned may see one extra record per sendpage().
Sticking to TCP semantics seems preferable to modifying
splice, but we can revisit it if real life scenarios
show a regression.
Reported-by: Vadim Fedorenko <vfedorenko@novek.ru>
Reported-by: Seth Forshee <seth.forshee@canonical.com>
Link: https://lore.kernel.org/netdev/1591392508-14592-1-git-send-email-pooja.trivedi@stackpath.com/
Fixes: 3c4d755915 ("tls: kernel TLS support")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Tested-by: Seth Forshee <seth.forshee@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This is a prerequisite patch, the next one is enabling recycling of
skbs and fragments. Add an extra argument on __skb_frag_unref() to
handle recycling, and update the current users of the function with that.
Signed-off-by: Matteo Croce <mcroce@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When a netdev with active TLS offload goes down, tls_device_down is
called to stop the offload and tear down the TLS context. However, the
socket stays alive, and it still points to the TLS context, which is now
deallocated. If a netdev goes up, while the connection is still active,
and the data flow resumes after a number of TCP retransmissions, it will
lead to a use-after-free of the TLS context.
This commit addresses this bug by keeping the context alive until its
normal destruction, and implements the necessary fallbacks, so that the
connection can resume in software (non-offloaded) kTLS mode.
On the TX side tls_sw_fallback is used to encrypt all packets. The RX
side already has all the necessary fallbacks, because receiving
non-decrypted packets is supported. The thing needed on the RX side is
to block resync requests, which are normally produced after receiving
non-decrypted packets.
The necessary synchronization is implemented for a graceful teardown:
first the fallbacks are deployed, then the driver resources are released
(it used to be possible to have a tls_dev_resync after tls_dev_del).
A new flag called TLS_RX_DEV_DEGRADED is added to indicate the fallback
mode. It's used to skip the RX resync logic completely, as it becomes
useless, and some objects may be released (for example, resync_async,
which is allocated and freed by the driver).
Fixes: e8f6979981 ("net/tls: Add generic NIC offload infrastructure")
Signed-off-by: Maxim Mikityanskiy <maximmi@nvidia.com>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
