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From: John Fastabend <john.fastabend@gmail.com>
To: netdev@vger.kernel.org, eadavis@qq.com, kuba@kernel.org
Cc: john.fastabend@gmail.com, bpf@vger.kernel.org, borisp@nvidia.com
Subject: [PATCH net 0/2] tls fixes for SPLICE with more hint
Date: Wed, 10 Jan 2024 14:01:22 -0800	[thread overview]
Message-ID: <20240110220124.452746-1-john.fastabend@gmail.com> (raw)

Syzbot found a splat where it tried to splice data over a tls socket
with the more hint and sending greater than the number of frags that
fit in a msg scatterlist. This resulted in an error where we do not
correctly send the data when the msg sg is full. The more flag being
just a hint not a strict contract. This then results in the syzbot
warning on the next send.

Edward generated an initial patch for this which checked for a full
msg on entry to the sendmsg hook.  This fixed the WARNING, but didn't
fully resolve the issue because the full msg_pl scatterlist was never
sent resulting in a stuck socket. In this series instead avoid the
situation by forcing the send on the splice that fills the scatterlist.

Also in original thread I mentioned it didn't seem to be enough to
simply fix the send on full sg problem. That was incorrect and was
really a bug in my test program that was hanging the test program.
I had setup a repair socket and wasn't handling it correctly so my
tester got stuck.

Thanks. Please review. Fix in patch 1 and test in patch 2.


John Fastabend (2):
  net: tls, fix WARNIING in __sk_msg_free
  net: tls, add test to capture error on large splice

 net/tls/tls_sw.c                  |  6 +++++-
 tools/testing/selftests/net/tls.c | 14 ++++++++++++++
 2 files changed, 19 insertions(+), 1 deletion(-)

-- 
2.33.0


             reply	other threads:[~2024-01-10 22:01 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-01-10 22:01 John Fastabend [this message]
2024-01-10 22:01 ` [PATCH net 1/2] net: tls, fix WARNIING in __sk_msg_free John Fastabend
2024-01-12  1:05   ` Jakub Kicinski
2024-01-10 22:01 ` [PATCH net 2/2] net: tls, add test to capture error on large splice John Fastabend
2024-01-12  1:05   ` Jakub Kicinski
2024-01-12 21:52     ` John Fastabend

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