| Message ID | YIE+fTOOnC9PLXbg@mwanda (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | SUNRPC: fix ternary sign expansion bug in tracing | expand |
> On Apr 22, 2021, at 5:14 AM, Dan Carpenter <dan.carpenter@oracle.com> wrote: > > This code is supposed to pass negative "err" values for tracing but it > passes positive values instead. The problem is that the > trace_svcsock_tcp_send() function takes a long but "err" is an int and > "sent" is a u32. The negative is first type promoted to u32 so it > becomes a high positive then it is promoted to long and it stays > positive. > > Fix this by casting "err" directly to long. > > Fixes: 998024dee197 ("SUNRPC: Add more svcsock tracepoints") > Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> I had a patch somewhere that simplified this logic and got rid of the ternary, but I think it got postponed when Trond recently changed the use of MSG_MORE. Let's go with this for now. I've pushed it to the for-next branch at: git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux.git > --- > net/sunrpc/svcsock.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/net/sunrpc/svcsock.c b/net/sunrpc/svcsock.c > index 9eb5b6b89077..478f857cdaed 100644 > --- a/net/sunrpc/svcsock.c > +++ b/net/sunrpc/svcsock.c > @@ -1174,7 +1174,7 @@ static int svc_tcp_sendto(struct svc_rqst *rqstp) > tcp_sock_set_cork(svsk->sk_sk, true); > err = svc_tcp_sendmsg(svsk->sk_sock, xdr, marker, &sent); > xdr_free_bvec(xdr); > - trace_svcsock_tcp_send(xprt, err < 0 ? err : sent); > + trace_svcsock_tcp_send(xprt, err < 0 ? (long)err : sent); > if (err < 0 || sent != (xdr->len + sizeof(marker))) > goto out_close; > if (atomic_dec_and_test(&svsk->sk_sendqlen)) > -- > 2.30.2 > -- Chuck Lever
diff --git a/net/sunrpc/svcsock.c b/net/sunrpc/svcsock.c index 9eb5b6b89077..478f857cdaed 100644 --- a/net/sunrpc/svcsock.c +++ b/net/sunrpc/svcsock.c @@ -1174,7 +1174,7 @@ static int svc_tcp_sendto(struct svc_rqst *rqstp) tcp_sock_set_cork(svsk->sk_sk, true); err = svc_tcp_sendmsg(svsk->sk_sock, xdr, marker, &sent); xdr_free_bvec(xdr); - trace_svcsock_tcp_send(xprt, err < 0 ? err : sent); + trace_svcsock_tcp_send(xprt, err < 0 ? (long)err : sent); if (err < 0 || sent != (xdr->len + sizeof(marker))) goto out_close; if (atomic_dec_and_test(&svsk->sk_sendqlen))
This code is supposed to pass negative "err" values for tracing but it passes positive values instead. The problem is that the trace_svcsock_tcp_send() function takes a long but "err" is an int and "sent" is a u32. The negative is first type promoted to u32 so it becomes a high positive then it is promoted to long and it stays positive. Fix this by casting "err" directly to long. Fixes: 998024dee197 ("SUNRPC: Add more svcsock tracepoints") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> --- net/sunrpc/svcsock.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)