diff options
| author | John Fastabend <john.fastabend@gmail.com> | 2021-07-27 09:05:00 -0700 |
|---|---|---|
| committer | Andrii Nakryiko <andrii@kernel.org> | 2021-07-27 14:55:30 -0700 |
| commit | 9635720b7c88592214562cb72605bdab6708006c (patch) | |
| tree | adead7fa8fe7b2e7668ce45327fc1a5e9ff9505e /net | |
| parent | 476d98018f32e68e7c5d4e8456940cf2b6d66f10 (diff) | |
| download | lwn-9635720b7c88592214562cb72605bdab6708006c.tar.gz lwn-9635720b7c88592214562cb72605bdab6708006c.zip | |
bpf, sockmap: Fix memleak on ingress msg enqueue
If backlog handler is running during a tear down operation we may enqueue
data on the ingress msg queue while tear down is trying to free it.
sk_psock_backlog()
sk_psock_handle_skb()
skb_psock_skb_ingress()
sk_psock_skb_ingress_enqueue()
sk_psock_queue_msg(psock,msg)
spin_lock(ingress_lock)
sk_psock_zap_ingress()
_sk_psock_purge_ingerss_msg()
_sk_psock_purge_ingress_msg()
-- free ingress_msg list --
spin_unlock(ingress_lock)
spin_lock(ingress_lock)
list_add_tail(msg,ingress_msg) <- entry on list with no one
left to free it.
spin_unlock(ingress_lock)
To fix we only enqueue from backlog if the ENABLED bit is set. The tear
down logic clears the bit with ingress_lock set so we wont enqueue the
msg in the last step.
Fixes: 799aa7f98d53 ("skmsg: Avoid lock_sock() in sk_psock_backlog()")
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Jakub Sitnicki <jakub@cloudflare.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20210727160500.1713554-4-john.fastabend@gmail.com
Diffstat (limited to 'net')
| -rw-r--r-- | net/core/skmsg.c | 6 |
1 files changed, 0 insertions, 6 deletions
diff --git a/net/core/skmsg.c b/net/core/skmsg.c index 036cdb33a94a..2d6249b28928 100644 --- a/net/core/skmsg.c +++ b/net/core/skmsg.c @@ -584,12 +584,6 @@ static int sk_psock_handle_skb(struct sk_psock *psock, struct sk_buff *skb, return sk_psock_skb_ingress(psock, skb); } -static void sock_drop(struct sock *sk, struct sk_buff *skb) -{ - sk_drops_add(sk, skb); - kfree_skb(skb); -} - static void sk_psock_skb_state(struct sk_psock *psock, struct sk_psock_work_state *state, struct sk_buff *skb, |