mainline inclusion
from mainline-5.17-rc1
commit d995816b
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=d995816b77eb826e0f6d7adf4471ec191b362be0

-------------------------------------------------

Alexei pointed out that we can use BPF_REG_0 which already contains imm
from move_blob2blob computation. Note that we now compare the second
insn's imm, but this should not matter, since both will be zeroed out
for the error case for the insn populated earlier.
Suggested-by: NAlexei Starovoitov <ast@kernel.org>
Signed-off-by: NKumar Kartikeya Dwivedi <memxor@gmail.com>
Signed-off-by: NAndrii Nakryiko <andrii@kernel.org>
Acked-by: NSong Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20211122235733.634914-4-memxor@gmail.com
(cherry picked from commit d995816b)
Signed-off-by: NWang Yufen <wangyufen@huawei.com>