]> git.proxmox.com Git - mirror_ubuntu-kernels.git/commit
bpf, sockmap: Wake up polling after data copy
authorJohn Fastabend <john.fastabend@gmail.com>
Tue, 23 May 2023 02:56:11 +0000 (19:56 -0700)
committerDaniel Borkmann <daniel@iogearbox.net>
Tue, 23 May 2023 14:10:35 +0000 (16:10 +0200)
commit6df7f764cd3cf5a03a4a47b23be47e57e41fcd85
tree89d749f66f0b69e481da3ca9679cda1c48181cd0
parentea444185a6bf7da4dd0df1598ee953e4f7174858
bpf, sockmap: Wake up polling after data copy

When TCP stack has data ready to read sk_data_ready() is called. Sockmap
overwrites this with its own handler to call into BPF verdict program.
But, the original TCP socket had sock_def_readable that would additionally
wake up any user space waiters with sk_wake_async().

Sockmap saved the callback when the socket was created so call the saved
data ready callback and then we can wake up any epoll() logic waiting
on the read.

Note we call on 'copied >= 0' to account for returning 0 when a FIN is
received because we need to wake up user for this as well so they
can do the recvmsg() -> 0 and detect the shutdown.

Fixes: 04919bed948dc ("tcp: Introduce tcp_read_skb()")
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Jakub Sitnicki <jakub@cloudflare.com>
Link: https://lore.kernel.org/bpf/20230523025618.113937-8-john.fastabend@gmail.com
net/core/skmsg.c