Fix a potential NULL-pointer exception in rxrpc_do_sendmsg(). The call
state check that I added should have gone into the else-body of the
if-statement where we actually have a call to check.
Found by CoverityScan CID#1414316 ("Dereference after null check").
Fixes: 540b1c48c37a ("rxrpc: Fix deadlock between call creation and
sendmsg/recvmsg")
Reported-by: Colin Ian King <colin.k...@canonical.com>
Signed-off-by: David Howells <dhowe...@redhat.com>
---
net/rxrpc/sendmsg.c | 15 ++++++++-------
1 file changed, 8 insertions(+), 7 deletions(-)
diff --git a/net/rxrpc/sendmsg.c b/net/rxrpc/sendmsg.c
index 31c1538c1a8d..27685d8cba1a 100644
--- a/net/rxrpc/sendmsg.c
+++ b/net/rxrpc/sendmsg.c
@@ -517,13 +517,6 @@ int rxrpc_do_sendmsg(struct rxrpc_sock *rx, struct msghdr
*msg, size_t len)
ret = -EBADSLT;
if (cmd != RXRPC_CMD_SEND_DATA)
goto error_release_sock;
- ret = -EBUSY;
- if (call->state == RXRPC_CALL_UNINITIALISED ||
- call->state == RXRPC_CALL_CLIENT_AWAIT_CONN ||
- call->state == RXRPC_CALL_SERVER_PREALLOC ||
- call->state == RXRPC_CALL_SERVER_SECURING ||
- call->state == RXRPC_CALL_SERVER_ACCEPTING)
- goto error_release_sock;
call = rxrpc_new_client_call_for_sendmsg(rx, msg, user_call_ID,
exclusive);
/* The socket is now unlocked... */
@@ -531,6 +524,14 @@ int rxrpc_do_sendmsg(struct rxrpc_sock *rx, struct msghdr
*msg, size_t len)
return PTR_ERR(call);
/* ... and we have the call lock. */
} else {
+ ret = -EBUSY;
+ if (call->state == RXRPC_CALL_UNINITIALISED ||
+ call->state == RXRPC_CALL_CLIENT_AWAIT_CONN ||
+ call->state == RXRPC_CALL_SERVER_PREALLOC ||
+ call->state == RXRPC_CALL_SERVER_SECURING ||
+ call->state == RXRPC_CALL_SERVER_ACCEPTING)
+ goto error_release_sock;
+
ret = mutex_lock_interruptible(&call->user_mutex);
release_sock(&rx->sk);
if (ret < 0) {
