net: add and use skb_unclone_keeptruesize() helper
authorEric Dumazet <edumazet@google.com>
Tue, 2 Nov 2021 00:45:55 +0000 (17:45 -0700)
committerJakub Kicinski <kuba@kernel.org>
Wed, 3 Nov 2021 01:10:34 +0000 (18:10 -0700)
commitc4777efa751d293e369aec464ce6875e957be255
tree88c4cb6d3fa42b985c17ef59447197a32c9a7128
parent236f57fe1b8853fb3505502c0f94ae64d153ae92
net: add and use skb_unclone_keeptruesize() helper

While commit 097b9146c0e2 ("net: fix up truesize of cloned
skb in skb_prepare_for_shift()") fixed immediate issues found
when KFENCE was enabled/tested, there are still similar issues,
when tcp_trim_head() hits KFENCE while the master skb
is cloned.

This happens under heavy networking TX workloads,
when the TX completion might be delayed after incoming ACK.

This patch fixes the WARNING in sk_stream_kill_queues
when sk->sk_mem_queued/sk->sk_forward_alloc are not zero.

Fixes: d3fb45f370d9 ("mm, kfence: insert KFENCE hooks for SLAB")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Marco Elver <elver@google.com>
Link: https://lore.kernel.org/r/20211102004555.1359210-1-eric.dumazet@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
include/linux/skbuff.h
net/core/skbuff.c
net/ipv4/tcp_output.c