From: Wang Yufen wangyufen@huawei.com
[ Upstream commit 8ec95b94716a1e4d126edc3fb2bc426a717e2dba ]
When running `test_sockmap` selftests, the following warning appears:
WARNING: CPU: 2 PID: 197 at net/core/stream.c:205 sk_stream_kill_queues+0xd3/0xf0 Call Trace: <TASK> inet_csk_destroy_sock+0x55/0x110 tcp_rcv_state_process+0xd28/0x1380 ? tcp_v4_do_rcv+0x77/0x2c0 tcp_v4_do_rcv+0x77/0x2c0 __release_sock+0x106/0x130 __tcp_close+0x1a7/0x4e0 tcp_close+0x20/0x70 inet_release+0x3c/0x80 __sock_release+0x3a/0xb0 sock_close+0x14/0x20 __fput+0xa3/0x260 task_work_run+0x59/0xb0 exit_to_user_mode_prepare+0x1b3/0x1c0 syscall_exit_to_user_mode+0x19/0x50 do_syscall_64+0x48/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae
The root case is in commit 84472b436e76 ("bpf, sockmap: Fix more uncharged while msg has more_data"), where I used msg->sg.size to replace the tosend, causing breakage:
if (msg->apply_bytes && msg->apply_bytes < tosend) tosend = psock->apply_bytes;
Fixes: 84472b436e76 ("bpf, sockmap: Fix more uncharged while msg has more_data") Reported-by: Jakub Sitnicki jakub@cloudflare.com Signed-off-by: Wang Yufen wangyufen@huawei.com Signed-off-by: Daniel Borkmann daniel@iogearbox.net Acked-by: John Fastabend john.fastabend@gmail.com Acked-by: Jakub Sitnicki jakub@cloudflare.com Link: https://lore.kernel.org/bpf/1667266296-8794-1-git-send-email-wangyufen@huawe... Signed-off-by: Sasha Levin sashal@kernel.org --- net/ipv4/tcp_bpf.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-)
diff --git a/net/ipv4/tcp_bpf.c b/net/ipv4/tcp_bpf.c index bcc13368c836..f69dcd3c7797 100644 --- a/net/ipv4/tcp_bpf.c +++ b/net/ipv4/tcp_bpf.c @@ -311,7 +311,7 @@ static int tcp_bpf_send_verdict(struct sock *sk, struct sk_psock *psock, { bool cork = false, enospc = sk_msg_full(msg); struct sock *sk_redir; - u32 tosend, delta = 0; + u32 tosend, origsize, sent, delta = 0; u32 eval = __SK_NONE; int ret;
@@ -366,10 +366,12 @@ static int tcp_bpf_send_verdict(struct sock *sk, struct sk_psock *psock, cork = true; psock->cork = NULL; } - sk_msg_return(sk, msg, msg->sg.size); + sk_msg_return(sk, msg, tosend); release_sock(sk);
+ origsize = msg->sg.size; ret = tcp_bpf_sendmsg_redir(sk_redir, msg, tosend, flags); + sent = origsize - msg->sg.size;
if (eval == __SK_REDIRECT) sock_put(sk_redir); @@ -408,7 +410,7 @@ static int tcp_bpf_send_verdict(struct sock *sk, struct sk_psock *psock, msg->sg.data[msg->sg.start].page_link && msg->sg.data[msg->sg.start].length) { if (eval == __SK_REDIRECT) - sk_mem_charge(sk, msg->sg.size); + sk_mem_charge(sk, tosend - sent); goto more_data; } }