diff options
author | Jakub Sitnicki <jakub@cloudflare.com> | 2020-02-06 12:16:51 +0100 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-02-14 16:52:59 -0500 |
commit | f22081df393f4540d8cdc3f56e1229e4a4550a00 (patch) | |
tree | a5c6d3c21e2970c2249149e0cf317e3559ac56f3 /net/core | |
parent | 448969a01d948d3fea8449ccf2fae379571de197 (diff) |
bpf, sockhash: Synchronize_rcu before free'ing map
commit 0b2dc83906cf1e694e48003eae5df8fa63f76fd9 upstream.
We need to have a synchronize_rcu before free'ing the sockhash because any
outstanding psock references will have a pointer to the map and when they
use it, this could trigger a use after free.
This is a sister fix for sockhash, following commit 2bb90e5cc90e ("bpf:
sockmap, synchronize_rcu before free'ing map") which addressed sockmap,
which comes from a manual audit.
Fixes: 604326b41a6fb ("bpf, sockmap: convert to generic sk_msg interface")
Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20200206111652.694507-3-jakub@cloudflare.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'net/core')
-rw-r--r-- | net/core/sock_map.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/net/core/sock_map.c b/net/core/sock_map.c index fd8b426dbdf3..f36e13e577a3 100644 --- a/net/core/sock_map.c +++ b/net/core/sock_map.c @@ -250,6 +250,7 @@ static void sock_map_free(struct bpf_map *map) } raw_spin_unlock_bh(&stab->lock); + /* wait for psock readers accessing its map link */ synchronize_rcu(); bpf_map_area_free(stab->sks); @@ -873,6 +874,9 @@ static void sock_hash_free(struct bpf_map *map) raw_spin_unlock_bh(&bucket->lock); } + /* wait for psock readers accessing its map link */ + synchronize_rcu(); + bpf_map_area_free(htab->buckets); kfree(htab); } |