diff options
| author | Hou Tao <houtao1@huawei.com> | 2022-08-10 11:05:32 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-08-25 12:37:55 +0300 |
| commit | d7ad7e65aa2fb5608b3b499aeaf1697f2e2e0cfd (patch) | |
| tree | d22fdf85059110a9774a019dfddd21ab64b0d49a /net/core | |
| parent | bda6fe3ea8932129881684ab52034673e36e6ae6 (diff) | |
| download | linux-d7ad7e65aa2fb5608b3b499aeaf1697f2e2e0cfd.tar.xz | |
bpf: Acquire map uref in .init_seq_private for sock local storage map iterator
commit 3c5f6e698b5c538bbb23cd453b22e1e4922cffd8 upstream.
bpf_iter_attach_map() acquires a map uref, and the uref may be released
before or in the middle of iterating map elements. For example, the uref
could be released in bpf_iter_detach_map() as part of
bpf_link_release(), or could be released in bpf_map_put_with_uref() as
part of bpf_map_release().
So acquiring an extra map uref in bpf_iter_init_sk_storage_map() and
releasing it in bpf_iter_fini_sk_storage_map().
Fixes: 5ce6e77c7edf ("bpf: Implement bpf iterator for sock local storage map")
Signed-off-by: Hou Tao <houtao1@huawei.com>
Acked-by: Yonghong Song <yhs@fb.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/r/20220810080538.1845898-4-houtao@huaweicloud.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'net/core')
| -rw-r--r-- | net/core/bpf_sk_storage.c | 10 |
1 files changed, 9 insertions, 1 deletions
diff --git a/net/core/bpf_sk_storage.c b/net/core/bpf_sk_storage.c index c907f0dc7f87..a25a96632064 100644 --- a/net/core/bpf_sk_storage.c +++ b/net/core/bpf_sk_storage.c @@ -794,10 +794,18 @@ static int bpf_iter_init_sk_storage_map(void *priv_data, { struct bpf_iter_seq_sk_storage_map_info *seq_info = priv_data; + bpf_map_inc_with_uref(aux->map); seq_info->map = aux->map; return 0; } +static void bpf_iter_fini_sk_storage_map(void *priv_data) +{ + struct bpf_iter_seq_sk_storage_map_info *seq_info = priv_data; + + bpf_map_put_with_uref(seq_info->map); +} + static int bpf_iter_attach_map(struct bpf_prog *prog, union bpf_iter_link_info *linfo, struct bpf_iter_aux_info *aux) @@ -843,7 +851,7 @@ static const struct seq_operations bpf_sk_storage_map_seq_ops = { static const struct bpf_iter_seq_info iter_seq_info = { .seq_ops = &bpf_sk_storage_map_seq_ops, .init_seq_private = bpf_iter_init_sk_storage_map, - .fini_seq_private = NULL, + .fini_seq_private = bpf_iter_fini_sk_storage_map, .seq_priv_size = sizeof(struct bpf_iter_seq_sk_storage_map_info), }; |