kcm: Fix locking issue
Lock the lower socket in kcm_unattach. Release during call to strp_done
since that function cancels the RX timers and work queue with sync.
Also added some status information in psock reporting.
Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/kcm/kcmproc.c b/net/kcm/kcmproc.c
index 47e4453..bf75c92 100644
--- a/net/kcm/kcmproc.c
+++ b/net/kcm/kcmproc.c
@@ -173,14 +173,24 @@
if (psock->strp.rx_stopped)
seq_puts(seq, "RxStop ");
- if (psock->strp.rx_paused)
- seq_puts(seq, "RxPause ");
-
if (psock->tx_kcm)
seq_printf(seq, "Rsvd-%d ", psock->tx_kcm->index);
- if (psock->ready_rx_msg)
- seq_puts(seq, "RdyRx ");
+ if (!psock->strp.rx_paused && !psock->ready_rx_msg) {
+ if (psock->sk->sk_receive_queue.qlen) {
+ if (psock->strp.rx_need_bytes)
+ seq_printf(seq, "RxWait=%u ",
+ psock->strp.rx_need_bytes);
+ else
+ seq_printf(seq, "RxWait ");
+ }
+ } else {
+ if (psock->strp.rx_paused)
+ seq_puts(seq, "RxPause ");
+
+ if (psock->ready_rx_msg)
+ seq_puts(seq, "RdyRx ");
+ }
seq_puts(seq, "\n");
}
diff --git a/net/kcm/kcmsock.c b/net/kcm/kcmsock.c
index eedbe40..eb731ca 100644
--- a/net/kcm/kcmsock.c
+++ b/net/kcm/kcmsock.c
@@ -1477,12 +1477,13 @@
return err;
}
-/* Lower socket lock held */
static void kcm_unattach(struct kcm_psock *psock)
{
struct sock *csk = psock->sk;
struct kcm_mux *mux = psock->mux;
+ lock_sock(csk);
+
/* Stop getting callbacks from TCP socket. After this there should
* be no way to reserve a kcm for this psock.
*/
@@ -1514,7 +1515,10 @@
write_unlock_bh(&csk->sk_callback_lock);
+ /* Call strp_done without sock lock */
+ release_sock(csk);
strp_done(&psock->strp);
+ lock_sock(csk);
bpf_prog_put(psock->bpf_prog);
@@ -1564,6 +1568,8 @@
fput(csk->sk_socket->file);
kmem_cache_free(kcm_psockp, psock);
}
+
+ release_sock(csk);
}
static int kcm_unattach_ioctl(struct socket *sock, struct kcm_unattach *info)
@@ -1749,11 +1755,8 @@
/* Release psocks */
list_for_each_entry_safe(psock, tmp_psock,
&mux->psocks, psock_list) {
- if (!WARN_ON(psock->unattaching)) {
- lock_sock(psock->strp.sk);
+ if (!WARN_ON(psock->unattaching))
kcm_unattach(psock);
- release_sock(psock->strp.sk);
- }
}
if (WARN_ON(mux->psocks_cnt))