From: Weiming Shi <bestswngs@gmail.com> mainline inclusion from mainline-v7.1-rc1 commit 5828b9e5b272ecff7cf5d345128d3de7324117f7 category: bugfix bugzilla: https://atomgit.com/openeuler/kernel/issues/9180 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i... -------------------------------- list_next_entry() never returns NULL -- when the current element is the last entry it wraps to the list head via container_of(). The subsequent NULL check is therefore dead code and get_next_key() never returns -ENOENT for the last element, instead reading storage->key from a bogus pointer that aliases internal map fields and copying the result to userspace. Replace it with list_entry_is_head() so the function correctly returns -ENOENT when there are no more entries. Fixes: de9cbbaadba5 ("bpf: introduce cgroup storage maps") Reported-by: Xiang Mei <xmei5@asu.edu> Signed-off-by: Weiming Shi <bestswngs@gmail.com> Reviewed-by: Sun Jian <sun.jian.kdev@gmail.com> Acked-by: Paul Chaignon <paul.chaignon@gmail.com> Link: https://lore.kernel.org/r/20260403132951.43533-2-bestswngs@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Pu Lehui <pulehui@huawei.com> --- kernel/bpf/local_storage.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/bpf/local_storage.c b/kernel/bpf/local_storage.c index a04f505aefe9..c8b8dcc37ed4 100644 --- a/kernel/bpf/local_storage.c +++ b/kernel/bpf/local_storage.c @@ -259,7 +259,7 @@ static int cgroup_storage_get_next_key(struct bpf_map *_map, void *key, goto enoent; storage = list_next_entry(storage, list_map); - if (!storage) + if (list_entry_is_head(storage, &map->list, list_map)) goto enoent; } else { storage = list_first_entry(&map->list, -- 2.34.1