Jakub Kicinski d452d48b9f tls: prevent oversized sendfile() hangs by ignoring MSG_MORE ... 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>		2021-06-21 12:39:08 -07:00
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Kconfig	net/tls: Select SOCK_RX_QUEUE_MAPPING from TLS_DEVICE	2021-02-11 19:08:06 -08:00
Makefile	net/tls: add skeleton of MIB statistics	2019-10-05 16:29:00 -07:00
tls_device_fallback.c	net/tls: Fix use-after-free after the TLS device goes down and up	2021-06-01 15:58:05 -07:00
tls_device.c	net/tls: Fix use-after-free after the TLS device goes down and up	2021-06-01 15:58:05 -07:00
tls_main.c	net/tls: Fix use-after-free after the TLS device goes down and up	2021-06-01 15:58:05 -07:00
tls_proc.c	net: fix proc_fs init handling in af_packet and tls	2020-12-14 19:39:30 -08:00
tls_sw.c	tls: prevent oversized sendfile() hangs by ignoring MSG_MORE	2021-06-21 12:39:08 -07:00
tls_toe.c	net/tls: rename tls_hw_* functions tls_toe_*	2019-10-04 14:07:07 -07:00
trace.c	net/tls: add tracing for device/offload events	2019-10-05 16:29:00 -07:00
trace.h	net/tls: add device decrypted trace point	2019-10-05 16:29:00 -07:00