mainline inclusion
from mainline-5.17-rc1
commit 401891a9
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I5EUVD
CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=401891a9debaf0a684502f2aaecf53448cee9414

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Perform a memory copy before we do the sanity checks of btf_ext_hdr.
This prevents misaligned memory access if raw btf_ext data is not 4-byte
aligned ([0]).

While at it, also add missing const qualifier.

  [0] Closes: https://github.com/libbpf/libbpf/issues/391

Fixes: 2993e051 ("tools/bpf: add support to read .BTF.ext sections")
Reported-by: NEvgeny Vereshchagin <evvers@ya.ru>
Signed-off-by: NAndrii Nakryiko <andrii@kernel.org>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20211124002325.1737739-3-andrii@kernel.org
(cherry picked from commit 401891a9)
Signed-off-by: NWang Yufen <wangyufen@huawei.com>