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Jakub Kicinski 581e37ad5c tls: prevent oversized sendfile() hangs by ignoring MSG_MORE
[ Upstream commit d452d48b9f8b1a7f8152d33ef52cfd7fe1735b0a ]

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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-07-14 16:56:24 +02:00
arch x86/sev: Split up runtime #VC handler for correct state tracking 2021-07-14 16:56:09 +02:00
block blk-mq: update hctx->dispatch_busy in case of real scheduler 2021-07-14 16:56:13 +02:00
certs certs: Add ability to preload revocation certs 2021-06-30 08:47:30 -04:00
crypto crypto: sm2 - fix a memory leak in sm2 2021-07-14 16:56:06 +02:00
Documentation mm/debug_vm_pgtable/basic: add validation for dirtiness after write protect 2021-07-14 16:56:13 +02:00
drivers vrf: do not push non-ND strict packets with a source LLA through packet taps again 2021-07-14 16:56:24 +02:00
fs dax: fix ENOMEM handling in grab_mapping_entry() 2021-07-14 16:56:13 +02:00
include net: sched: add barrier to ensure correct ordering for lockless qdisc 2021-07-14 16:56:24 +02:00
init sched/core: Initialize the idle task with preemption disabled 2021-07-14 16:55:50 +02:00
ipc ipc/mqueue, msg, sem: avoid relying on a stack reference past its expiry 2021-05-26 12:06:54 +02:00
kernel psi: Fix race between psi_trigger_create/destroy 2021-07-14 16:56:10 +02:00
lib lockdep/selftests: Fix selftests vs PROVE_RAW_LOCK_NESTING 2021-07-14 16:56:10 +02:00
LICENSES LICENSES/deprecated: add Zlib license text 2020-09-16 14:33:49 +02:00
mm mm/page_alloc: fix counting of managed_pages 2021-07-14 16:56:14 +02:00
net tls: prevent oversized sendfile() hangs by ignoring MSG_MORE 2021-07-14 16:56:24 +02:00
samples samples/bpf: Fix the error return code of xdp_redirect's main() 2021-07-14 16:56:23 +02:00
scripts kbuild: Fix objtool dependency for 'OBJECT_FILES_NON_STANDARD_<obj> := n' 2021-07-14 16:56:04 +02:00
security evm: fix writing <securityfs>/evm overflow 2021-07-14 16:56:04 +02:00
sound ALSA: hda/realtek: fix mute/micmute LEDs for HP EliteBook 830 G8 Notebook PC 2021-07-14 16:55:37 +02:00
tools bpf: Fix libelf endian handling in resolv_btfids 2021-07-14 16:56:23 +02:00
usr Merge branch 'work.fdpic' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2020-08-07 13:29:39 -07:00
virt KVM: do not allow mapping valid but non-reference-counted pages 2021-06-30 08:47:25 -04:00
.clang-format RDMA 5.10 pull request 2020-10-17 11:18:18 -07:00
.cocciconfig
.get_maintainer.ignore
.gitattributes
.gitignore kbuild: generate Module.symvers only when vmlinux exists 2021-05-19 10:12:59 +02:00
.mailmap mailmap: add two more addresses of Uwe Kleine-König 2020-12-06 10:19:07 -08:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS MAINTAINERS: Move Jason Cooper to CREDITS 2020-11-30 10:20:34 +01:00
Kbuild
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS f2fs: move ioctl interface definitions to separated file 2021-05-19 10:13:00 +02:00
Makefile Makefile: fix GDB warning with CONFIG_RELR 2021-07-14 16:55:53 +02:00
README

Linux kernel
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