From 419ce133ab928ab5efd7b50b2ef36ddfd4eadbd2 Mon Sep 17 00:00:00 2001 From: Paolo Abeni Date: Wed, 11 Oct 2023 09:20:55 +0200 Subject: tcp: allow again tcp_disconnect() when threads are waiting As reported by Tom, .NET and applications build on top of it rely on connect(AF_UNSPEC) to async cancel pending I/O operations on TCP socket. The blamed commit below caused a regression, as such cancellation can now fail. As suggested by Eric, this change addresses the problem explicitly causing blocking I/O operation to terminate immediately (with an error) when a concurrent disconnect() is executed. Instead of tracking the number of threads blocked on a given socket, track the number of disconnect() issued on such socket. If such counter changes after a blocking operation releasing and re-acquiring the socket lock, error out the current operation. Fixes: 4faeee0cf8a5 ("tcp: deny tcp_disconnect() when threads are waiting") Reported-by: Tom Deseyn Closes: https://bugzilla.redhat.com/show_bug.cgi?id=1886305 Suggested-by: Eric Dumazet Signed-off-by: Paolo Abeni Reviewed-by: Eric Dumazet Link: https://lore.kernel.org/r/f3b95e47e3dbed840960548aebaa8d954372db41.1697008693.git.pabeni@redhat.com Signed-off-by: Jakub Kicinski --- .../chelsio/inline_crypto/chtls/chtls_io.c | 36 +++++++++++++++++----- 1 file changed, 29 insertions(+), 7 deletions(-) (limited to 'drivers/net/ethernet/chelsio') diff --git a/drivers/net/ethernet/chelsio/inline_crypto/chtls/chtls_io.c b/drivers/net/ethernet/chelsio/inline_crypto/chtls/chtls_io.c index 5fc64e47568a..d567e42e1760 100644 --- a/drivers/net/ethernet/chelsio/inline_crypto/chtls/chtls_io.c +++ b/drivers/net/ethernet/chelsio/inline_crypto/chtls/chtls_io.c @@ -911,7 +911,7 @@ static int csk_wait_memory(struct chtls_dev *cdev, struct sock *sk, long *timeo_p) { DEFINE_WAIT_FUNC(wait, woken_wake_function); - int err = 0; + int ret, err = 0; long current_timeo; long vm_wait = 0; bool noblock; @@ -942,10 +942,13 @@ static int csk_wait_memory(struct chtls_dev *cdev, set_bit(SOCK_NOSPACE, &sk->sk_socket->flags); sk->sk_write_pending++; - sk_wait_event(sk, ¤t_timeo, sk->sk_err || - (sk->sk_shutdown & SEND_SHUTDOWN) || - (csk_mem_free(cdev, sk) && !vm_wait), &wait); + ret = sk_wait_event(sk, ¤t_timeo, sk->sk_err || + (sk->sk_shutdown & SEND_SHUTDOWN) || + (csk_mem_free(cdev, sk) && !vm_wait), + &wait); sk->sk_write_pending--; + if (ret < 0) + goto do_error; if (vm_wait) { vm_wait -= current_timeo; @@ -1348,6 +1351,7 @@ static int chtls_pt_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, int copied = 0; int target; long timeo; + int ret; buffers_freed = 0; @@ -1423,7 +1427,11 @@ static int chtls_pt_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, if (copied >= target) break; chtls_cleanup_rbuf(sk, copied); - sk_wait_data(sk, &timeo, NULL); + ret = sk_wait_data(sk, &timeo, NULL); + if (ret < 0) { + copied = copied ? : ret; + goto unlock; + } continue; found_ok_skb: if (!skb->len) { @@ -1518,6 +1526,8 @@ skip_copy: if (buffers_freed) chtls_cleanup_rbuf(sk, copied); + +unlock: release_sock(sk); return copied; } @@ -1534,6 +1544,7 @@ static int peekmsg(struct sock *sk, struct msghdr *msg, int copied = 0; size_t avail; /* amount of available data in current skb */ long timeo; + int ret; lock_sock(sk); timeo = sock_rcvtimeo(sk, flags & MSG_DONTWAIT); @@ -1585,7 +1596,12 @@ static int peekmsg(struct sock *sk, struct msghdr *msg, release_sock(sk); lock_sock(sk); } else { - sk_wait_data(sk, &timeo, NULL); + ret = sk_wait_data(sk, &timeo, NULL); + if (ret < 0) { + /* here 'copied' is 0 due to previous checks */ + copied = ret; + break; + } } if (unlikely(peek_seq != tp->copied_seq)) { @@ -1656,6 +1672,7 @@ int chtls_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, int copied = 0; long timeo; int target; /* Read at least this many bytes */ + int ret; buffers_freed = 0; @@ -1747,7 +1764,11 @@ int chtls_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, if (copied >= target) break; chtls_cleanup_rbuf(sk, copied); - sk_wait_data(sk, &timeo, NULL); + ret = sk_wait_data(sk, &timeo, NULL); + if (ret < 0) { + copied = copied ? : ret; + goto unlock; + } continue; found_ok_skb: @@ -1816,6 +1837,7 @@ skip_copy: if (buffers_freed) chtls_cleanup_rbuf(sk, copied); +unlock: release_sock(sk); return copied; } -- cgit