Lorenz Bauer 248e00ac47 bpf: cgroup: Allow multi-attach program to replace itself ... When using BPF_PROG_ATTACH to attach a program to a cgroup in BPF_F_ALLOW_MULTI mode, it is not possible to replace a program with itself. This is because the check for duplicate programs doesn't take the replacement program into account. Replacing a program with itself might seem weird, but it has some uses: first, it allows resetting the associated cgroup storage. Second, it makes the API consistent with the non-ALLOW_MULTI usage, where it is possible to replace a program with itself. Third, it aligns BPF_PROG_ATTACH with bpf_link, where replacing itself is also supported. Sice this code has been refactored a few times this change will only apply to v5.7 and later. Adjustments could be made to commit 1020c1f24a ("bpf: Simplify __cgroup_bpf_attach") and commit d7bf2c10af ("bpf: allocate cgroup storage entries on attaching bpf programs") as well as commit 324bda9e6c ("bpf: multi program support for cgroup+bpf") Fixes: af6eea5743 ("bpf: Implement bpf_link-based cgroup BPF program attachment") Signed-off-by: Lorenz Bauer <lmb@cloudflare.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20200608162202.94002-1-lmb@cloudflare.com		2020-06-09 11:21:43 -07:00
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fault-injection
ktest	ktest: Fix typos in ktest.pl	2020-03-09 16:15:27 -04:00
kunit	SPDX patches for 5.7-rc1.	2020-04-03 13:12:26 -07:00
nvdimm	tools/test/nvdimm: Fix out of tree build	2020-03-31 14:12:32 -07:00
radix-tree	SPDX patches for 5.7-rc1.	2020-04-03 13:12:26 -07:00
scatterlist
selftests	bpf: cgroup: Allow multi-attach program to replace itself	2020-06-09 11:21:43 -07:00
vsock	SPDX patches for 5.7-rc1.	2020-04-03 13:12:26 -07:00