linux.git/net/tls, branch for-next

tls: Fix tls_sw_sendmsg error handling

2025-01-08T01:00:19+00:00

We've noticed that NFS can hang when using RPC over TLS on an unstable
connection, and investigation shows that the RPC layer is stuck in a tight
loop attempting to transmit, but forever getting -EBADMSG back from the
underlying network.  The loop begins when tcp_sendmsg_locked() returns
-EPIPE to tls_tx_records(), but that error is converted to -EBADMSG when
calling the socket's error reporting handler.

Instead of converting errors from tcp_sendmsg_locked(), let's pass them
along in this path.  The RPC layer handles -EPIPE by reconnecting the
transport, which prevents the endless attempts to transmit on a broken
connection.

Signed-off-by: Benjamin Coddington 
Fixes: a42055e8d2c3 ("net/tls: Add support for async encryption of records for performance")
Link: https://patch.msgid.link/9594185559881679d81f071b181a10eb07cd079f.1736004079.git.bcodding@redhat.com
Signed-off-by: Jakub Kicinski

move asm/unaligned.h to linux/unaligned.h

2024-10-02T21:23:23+00:00

asm/unaligned.h is always an include of asm-generic/unaligned.h;
might as well move that thing to linux/unaligned.h and include
that - there's nothing arch-specific in that header.

auto-generated by the following:

for i in `git grep -l -w asm/unaligned.h`; do
	sed -i -e "s/asm\/unaligned.h/linux\/unaligned.h/" $i
done
for i in `git grep -l -w asm-generic/unaligned.h`; do
	sed -i -e "s/asm-generic\/unaligned.h/linux\/unaligned.h/" $i
done
git mv include/asm-generic/unaligned.h include/linux/unaligned.h
git mv tools/include/asm-generic/unaligned.h tools/include/linux/unaligned.h
sed -i -e "/unaligned.h/d" include/asm-generic/Kbuild
sed -i -e "s/__ASM_GENERIC/__LINUX/" include/linux/unaligned.h tools/include/linux/unaligned.h

net: tls: wait for async completion on last message

2024-09-07T01:20:55+00:00

When asynchronous encryption is used KTLS sends out the final data at
proto->close time. This becomes problematic when the task calling
close() receives a signal. In this case it can happen that
tcp_sendmsg_locked() called at close time returns -ERESTARTSYS and the
final data is not sent.

The described situation happens when KTLS is used in conjunction with
io_uring, as io_uring uses task_work_add() to add work to the current
userspace task. A discussion of the problem along with a reproducer can
be found in [1] and [2]

Fix this by waiting for the asynchronous encryption to be completed on
the final message. With this there is no data left to be sent at close
time.

[1] https://lore.kernel.org/all/20231010141932.GD3114228@pengutronix.de/
[2] https://lore.kernel.org/all/20240315100159.3898944-1-s.hauer@pengutronix.de/

Signed-off-by: Sascha Hauer 
Link: https://patch.msgid.link/20240904-ktls-wait-async-v1-1-a62892833110@pengutronix.de
Signed-off-by: Jakub Kicinski

net: tls: Pass union tls_crypto_context pointer to memzero_explicit

2024-07-09T18:14:47+00:00

Pass union tls_crypto_context pointer, rather than struct
tls_crypto_info pointer, to memzero_explicit().

The address of the pointer is the same before and after.
But the new construct means that the size of the dereferenced pointer type
matches the size being zeroed. Which aids static analysis.

As reported by Smatch:

  .../tls_main.c:842 do_tls_setsockopt_conf() error: memzero_explicit() 'crypto_info' too small (4 vs 56)

No functional change intended.
Compile tested only.

Reviewed-by: Przemek Kitszel 
Signed-off-by: Simon Horman 
Link: https://patch.msgid.link/20240708-tls-memzero-v2-1-9694eaf31b79@kernel.org
Signed-off-by: Jakub Kicinski

tcp: add a helper for setting EOR on tail skb

2024-06-04T11:23:30+00:00

TLS (and hopefully soon PSP will) use EOR to prevent skbs
with different decrypted state from getting merged, without
adding new tests to the skb handling. In both cases once
the connection switches to an "encrypted" state, all subsequent
skbs will be encrypted, so a single "EOR fence" is sufficient
to prevent mixing.

Add a helper for setting the EOR bit, to make this arrangement
more explicit.

Signed-off-by: Jakub Kicinski 
Reviewed-by: Eric Dumazet 
Reviewed-by: Willem de Bruijn 
Signed-off-by: Paolo Abeni

tls: fix missing memory barrier in tls_init

2024-05-23T10:03:26+00:00

In tls_init(), a write memory barrier is missing, and store-store
reordering may cause NULL dereference in tls_{setsockopt,getsockopt}.

CPU0                               CPU1
-----                              -----
// In tls_init()
// In tls_ctx_create()
ctx = kzalloc()
ctx->sk_proto = READ_ONCE(sk->sk_prot) -(1)

// In update_sk_prot()
WRITE_ONCE(sk->sk_prot, tls_prots)     -(2)

                                   // In sock_common_setsockopt()
                                   READ_ONCE(sk->sk_prot)->setsockopt()

                                   // In tls_{setsockopt,getsockopt}()
                                   ctx->sk_proto->setsockopt()    -(3)

In the above scenario, when (1) and (2) are reordered, (3) can observe
the NULL value of ctx->sk_proto, causing NULL dereference.

To fix it, we rely on rcu_assign_pointer() which implies the release
barrier semantic. By moving rcu_assign_pointer() after ctx->sk_proto is
initialized, we can ensure that ctx->sk_proto are visible when
changing sk->sk_prot.

Fixes: d5bee7374b68 ("net/tls: Annotate access to sk_prot with READ_ONCE/WRITE_ONCE")
Signed-off-by: Yewon Choi 
Signed-off-by: Dae R. Jeong 
Link: https://lore.kernel.org/netdev/ZU4OJG56g2V9z_H7@dragonet/T/
Link: https://lore.kernel.org/r/Zkx4vjSFp0mfpjQ2@libra05
Signed-off-by: Paolo Abeni

Revert "net: mirror skb frag ref/unref helpers"

2024-05-03T23:05:53+00:00

This reverts commit a580ea994fd37f4105028f5a85c38ff6508a2b25.

This revert is to resolve Dragos's report of page_pool leak here:
https://lore.kernel.org/lkml/20240424165646.1625690-2-dtatulea@nvidia.com/

The reverted patch interacts very badly with commit 2cc3aeb5eccc ("skbuff:
Fix a potential race while recycling page_pool packets"). The reverted
commit hopes that the pp_recycle + is_pp_page variables do not change
between the skb_frag_ref and skb_frag_unref operation. If such a change
occurs, the skb_frag_ref/unref will not operate on the same reference type.
In the case of Dragos's report, the grabbed ref was a pp ref, but the unref
was a page ref, because the pp_recycle setting on the skb was changed.

Attempting to fix this issue on the fly is risky. Lets revert and I hope
to reland this with better understanding and testing to ensure we don't
regress some edge case while streamlining skb reffing.

Fixes: a580ea994fd3 ("net: mirror skb frag ref/unref helpers")
Reported-by: Dragos Tatulea 
Signed-off-by: Mina Almasry 
Link: https://lore.kernel.org/r/20240502175423.2456544-1-almasrymina@google.com
Signed-off-by: Jakub Kicinski

Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

2024-04-25T19:41:37+00:00

Cross-merge networking fixes after downstream PR.

Conflicts:

drivers/net/ethernet/ti/icssg/icssg_prueth.c

net/mac80211/chan.c
  89884459a0b9 ("wifi: mac80211: fix idle calculation with multi-link")
  87f5500285fb ("wifi: mac80211: simplify ieee80211_assign_link_chanctx()")
https://lore.kernel.org/all/20240422105623.7b1fbda2@canb.auug.org.au/

net/unix/garbage.c
  1971d13ffa84 ("af_unix: Suppress false-positive lockdep splat for spin_lock() in __unix_gc().")
  4090fa373f0e ("af_unix: Replace garbage collection algorithm.")

drivers/net/ethernet/ti/icssg/icssg_prueth.c
drivers/net/ethernet/ti/icssg/icssg_common.c
  4dcd0e83ea1d ("net: ti: icssg-prueth: Fix signedness bug in prueth_init_rx_chns()")
  e2dc7bfd677f ("net: ti: icssg-prueth: Move common functions into a separate file")

No adjacent changes.

Signed-off-by: Jakub Kicinski

tls: fix lockless read of strp->msg_ready in ->poll

2024-04-25T15:32:37+00:00

tls_sk_poll is called without locking the socket, and needs to read
strp->msg_ready (via tls_strp_msg_ready). Convert msg_ready to a bool
and use READ_ONCE/WRITE_ONCE where needed. The remaining reads are
only performed when the socket is locked.

Fixes: 121dca784fc0 ("tls: suppress wakeups unless we have a full record")
Signed-off-by: Sabrina Dubroca 
Link: https://lore.kernel.org/r/0b7ee062319037cf86af6b317b3d72f7bfcd2e97.1713797701.git.sd@queasysnail.net
Signed-off-by: Jakub Kicinski

tls: remove redundant assignment to variable decrypted

2024-04-12T03:00:22+00:00

The variable decrypted is being assigned a value that is never read,
the control of flow after the assignment is via an return path and
decrypted is not referenced in this path. The assignment is redundant
and can be removed.

Cleans up clang scan warning:
net/tls/tls_sw.c:2150:4: warning: Value stored to 'decrypted' is never
read [deadcode.DeadStores]

Signed-off-by: Colin Ian King 
Link: https://lore.kernel.org/r/20240410144136.289030-1-colin.i.king@gmail.com
Signed-off-by: Jakub Kicinski