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| author | David Howells <dhowells@redhat.com> | 2022-12-24 14:49:00 +0000 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2022-12-28 09:59:23 +0000 |
| commit | 0e50d999903c009b6a9cd2277c82d6798d982e31 (patch) | |
| tree | 2c8c72932a63fcd1c526699b15ec3ce9ae72c85a /net/rxrpc | |
| parent | d3805695fe1e7383517903715cefc9bbdcffdc90 (diff) | |
| download | linux-0e50d999903c009b6a9cd2277c82d6798d982e31.tar.bz2 | |
rxrpc: Fix a couple of potential use-after-frees
At the end of rxrpc_recvmsg(), if a call is found, the call is put and then
a trace line is emitted referencing that call in a couple of places - but
the call may have been deallocated by the time those traces happen.
Fix this by stashing the call debug_id in a variable and passing that to
the tracepoint rather than the call pointer.
Fixes: 849979051cbc ("rxrpc: Add a tracepoint to follow what recvmsg does")
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: linux-afs@lists.infradead.org
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/rxrpc')
| -rw-r--r-- | net/rxrpc/recvmsg.c | 14 |
1 files changed, 8 insertions, 6 deletions
diff --git a/net/rxrpc/recvmsg.c b/net/rxrpc/recvmsg.c index 36b25d003cf0..6ebd6440a2b7 100644 --- a/net/rxrpc/recvmsg.c +++ b/net/rxrpc/recvmsg.c @@ -388,13 +388,14 @@ int rxrpc_recvmsg(struct socket *sock, struct msghdr *msg, size_t len, struct rxrpc_call *call; struct rxrpc_sock *rx = rxrpc_sk(sock->sk); struct list_head *l; + unsigned int call_debug_id = 0; size_t copied = 0; long timeo; int ret; DEFINE_WAIT(wait); - trace_rxrpc_recvmsg(NULL, rxrpc_recvmsg_enter, 0); + trace_rxrpc_recvmsg(0, rxrpc_recvmsg_enter, 0); if (flags & (MSG_OOB | MSG_TRUNC)) return -EOPNOTSUPP; @@ -431,7 +432,7 @@ try_again: if (list_empty(&rx->recvmsg_q)) { if (signal_pending(current)) goto wait_interrupted; - trace_rxrpc_recvmsg(NULL, rxrpc_recvmsg_wait, 0); + trace_rxrpc_recvmsg(0, rxrpc_recvmsg_wait, 0); timeo = schedule_timeout(timeo); } finish_wait(sk_sleep(&rx->sk), &wait); @@ -450,7 +451,8 @@ try_again: rxrpc_get_call(call, rxrpc_call_get_recvmsg); write_unlock(&rx->recvmsg_lock); - trace_rxrpc_recvmsg(call, rxrpc_recvmsg_dequeue, 0); + call_debug_id = call->debug_id; + trace_rxrpc_recvmsg(call_debug_id, rxrpc_recvmsg_dequeue, 0); /* We're going to drop the socket lock, so we need to lock the call * against interference by sendmsg. @@ -531,7 +533,7 @@ try_again: error_unlock_call: mutex_unlock(&call->user_mutex); rxrpc_put_call(call, rxrpc_call_put_recvmsg); - trace_rxrpc_recvmsg(call, rxrpc_recvmsg_return, ret); + trace_rxrpc_recvmsg(call_debug_id, rxrpc_recvmsg_return, ret); return ret; error_requeue_call: @@ -539,14 +541,14 @@ error_requeue_call: write_lock(&rx->recvmsg_lock); list_add(&call->recvmsg_link, &rx->recvmsg_q); write_unlock(&rx->recvmsg_lock); - trace_rxrpc_recvmsg(call, rxrpc_recvmsg_requeue, 0); + trace_rxrpc_recvmsg(call_debug_id, rxrpc_recvmsg_requeue, 0); } else { rxrpc_put_call(call, rxrpc_call_put_recvmsg); } error_no_call: release_sock(&rx->sk); error_trace: - trace_rxrpc_recvmsg(call, rxrpc_recvmsg_return, ret); + trace_rxrpc_recvmsg(call_debug_id, rxrpc_recvmsg_return, ret); return ret; wait_interrupted: |