linux/tools
Martin KaFai Lau a5fa25adf0 bpf: Change bpf_sk_release and bpf_sk_*cgroup_id to accept ARG_PTR_TO_BTF_ID_SOCK_COMMON
The previous patch allows the networking bpf prog to use the
bpf_skc_to_*() helpers to get a PTR_TO_BTF_ID socket pointer,
e.g. "struct tcp_sock *".  It allows the bpf prog to read all the
fields of the tcp_sock.

This patch changes the bpf_sk_release() and bpf_sk_*cgroup_id()
to take ARG_PTR_TO_BTF_ID_SOCK_COMMON such that they will
work with the pointer returned by the bpf_skc_to_*() helpers
also.  For example, the following will work:

	sk = bpf_skc_lookup_tcp(skb, tuple, tuplen, BPF_F_CURRENT_NETNS, 0);
	if (!sk)
		return;
	tp = bpf_skc_to_tcp_sock(sk);
	if (!tp) {
		bpf_sk_release(sk);
		return;
	}
	lsndtime = tp->lsndtime;
	/* Pass tp to bpf_sk_release() will also work */
	bpf_sk_release(tp);

Since PTR_TO_BTF_ID could be NULL, the helper taking
ARG_PTR_TO_BTF_ID_SOCK_COMMON has to check for NULL at runtime.

A btf_id of "struct sock" may not always mean a fullsock.  Regardless
the helper's running context may get a non-fullsock or not,
considering fullsock check/handling is pretty cheap, it is better to
keep the same verifier expectation on helper that takes ARG_PTR_TO_BTF_ID*
will be able to handle the minisock situation.  In the bpf_sk_*cgroup_id()
case,  it will try to get a fullsock by using sk_to_full_sk() as its
skb variant bpf_sk"b"_*cgroup_id() has already been doing.

bpf_sk_release can already handle minisock, so nothing special has to
be done.

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200925000356.3856047-1-kafai@fb.com
2020-09-25 13:58:01 -07:00
..
accounting
arch tools headers kvm s390: Sync headers with the kernel sources 2020-08-12 08:52:32 -03:00
bootconfig tools/bootconfig: Add testcases for value override operator 2020-08-03 16:22:29 -04:00
bpf Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next 2020-09-23 13:11:11 -07:00
build tools, bpf/build: Cleanup feature files on make clean 2020-08-28 14:04:27 +02:00
cgroup tools/cgroup: add memcg_slabinfo.py tool 2020-08-07 11:33:25 -07:00
debugging
edid
firewire
firmware
gpio tools: gpio: fix spurious close warning in gpio-event-mon 2020-07-12 10:22:01 +02:00
hv tools: hv: change http to https in hv_kvp_daemon.c 2020-07-06 10:46:23 +00:00
iio
include bpf: Change bpf_sk_release and bpf_sk_*cgroup_id to accept ARG_PTR_TO_BTF_ID_SOCK_COMMON 2020-09-25 13:58:01 -07:00
io_uring tools/io_uring: fix compile breakage 2020-09-21 07:50:58 -06:00
kvm/kvm_stat
laptop
leds
lib Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next 2020-09-23 13:11:11 -07:00
memory-model These were the main changes in this cycle: 2020-08-03 14:39:35 -07:00
nfsd
objtool objtool: Fix noreturn detection for ignored functions 2020-09-18 19:37:51 +02:00
pci
pcmcia
perf Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next 2020-09-23 13:11:11 -07:00
power ACPI updates for 5.9-rc1 2020-08-03 20:37:22 -07:00
scripts
spi
testing Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next 2020-09-23 13:11:11 -07:00
thermal/tmon
time
usb tools: usb: move to tools buildsystem 2020-08-19 14:11:44 +02:00
virtio virtio: fixes, features 2020-08-11 14:34:17 -07:00
vm
wmi
Makefile bpf: Compile resolve_btfids tool at kernel compilation start 2020-07-13 10:42:02 -07:00