bpf: Add missed allocation hint for bpf_mem_cache_alloc_flags()

stable inclusion
from stable-v6.6.5
commit d9105720404c2c35ae79949a06a95ce88ef6280e
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I8N21P

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=d9105720404c2c35ae79949a06a95ce88ef6280e



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[ Upstream commit 75a442581d05edaee168222ffbe00d4389785636 ]

bpf_mem_cache_alloc_flags() may call __alloc() directly when there is no
free object in free list, but it doesn't initialize the allocation hint
for the returned pointer. It may lead to bad memory dereference when
freeing the pointer, so fix it by initializing the allocation hint.

Fixes: 822fb26b ("bpf: Add a hint to allocated objects.")
Signed-off-by: Hou Tao <houtao1@huawei.com>
Acked-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/r/20231111043821.2258513-1-houtao@huaweicloud.com


Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>