diff mbox series

rxrpc: Fix uninitialized error code in rxrpc_send_data_packet()

Message ID 15499.1559298884@warthog.procyon.org.uk (mailing list archive)
State New, archived
Headers show
Series rxrpc: Fix uninitialized error code in rxrpc_send_data_packet() | expand

Commit Message

David Howells May 31, 2019, 10:34 a.m. UTC
Hi Geert,

Here's my take on the patch.

David
---
rxrpc: Fix uninitialized error code in rxrpc_send_data_packet()    
    
With gcc 4.1:

    net/rxrpc/output.c: In function ‘rxrpc_send_data_packet’:
    net/rxrpc/output.c:338: warning: ‘ret’ may be used uninitialized in this function

Indeed, if the first jump to the send_fragmentable label is made, and
the address family is not handled in the switch() statement, ret will be
used uninitialized.

Fix this by BUG()'ing as is done in other places in rxrpc where internal
support for future address families will need adding.  It should not be
possible to reach this normally as the address families are checked
up-front.

Fixes: 5a924b8951f835b5 ("rxrpc: Don't store the rxrpc header in the Tx queue sk_buffs")
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: David Howells <dhowells@redhat.com>
---

Comments

David Miller June 3, 2019, 9:30 p.m. UTC | #1
From: David Howells <dhowells@redhat.com>
Date: Fri, 31 May 2019 11:34:44 +0100

> Here's my take on the patch.

I assume I'll see a final version of this under separate cover.
Geert Uytterhoeven June 4, 2019, 7:17 a.m. UTC | #2
Hi David,

On Fri, May 31, 2019 at 12:35 PM David Howells <dhowells@redhat.com> wrote:
> Here's my take on the patch.
>
> David
> ---
> rxrpc: Fix uninitialized error code in rxrpc_send_data_packet()
>
> With gcc 4.1:
>
>     net/rxrpc/output.c: In function ‘rxrpc_send_data_packet’:
>     net/rxrpc/output.c:338: warning: ‘ret’ may be used uninitialized in this function
>
> Indeed, if the first jump to the send_fragmentable label is made, and
> the address family is not handled in the switch() statement, ret will be
> used uninitialized.
>
> Fix this by BUG()'ing as is done in other places in rxrpc where internal
> support for future address families will need adding.  It should not be
> possible to reach this normally as the address families are checked
> up-front.
>
> Fixes: 5a924b8951f835b5 ("rxrpc: Don't store the rxrpc header in the Tx queue sk_buffs")
> Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
> Signed-off-by: David Howells <dhowells@redhat.com>

I'm not such a big fan of BUG(), so I'd go for ret = -EAFNOSUPPORT, but given
rxrpc is already full of BUG() calls, I guess it is an acceptable solution.

> ---
> diff --git a/net/rxrpc/output.c b/net/rxrpc/output.c
> index 004c762c2e8d..6f2b4fb4b0aa 100644
> --- a/net/rxrpc/output.c
> +++ b/net/rxrpc/output.c
> @@ -523,6 +523,9 @@ int rxrpc_send_data_packet(struct rxrpc_call *call, struct sk_buff *skb,
>                 }
>                 break;
>  #endif
> +
> +       default:
> +               BUG();
>         }
>
>         if (ret < 0)

Gr{oetje,eeting}s,

                        Geert
David Howells June 4, 2019, 7:34 a.m. UTC | #3
Geert Uytterhoeven <geert@linux-m68k.org> wrote:

> I'm not such a big fan of BUG(), so I'd go for ret = -EAFNOSUPPORT, but given
> rxrpc is already full of BUG() calls, I guess it is an acceptable solution.

Okay.  Are you okay with this going through net-next?

David
Geert Uytterhoeven June 4, 2019, 7:35 a.m. UTC | #4
Hi David,

On Tue, Jun 4, 2019 at 9:34 AM David Howells <dhowells@redhat.com> wrote:
> Geert Uytterhoeven <geert@linux-m68k.org> wrote:
>
> > I'm not such a big fan of BUG(), so I'd go for ret = -EAFNOSUPPORT, but given
> > rxrpc is already full of BUG() calls, I guess it is an acceptable solution.
>
> Okay.  Are you okay with this going through net-next?

Yes, I am.

Gr{oetje,eeting}s,

                        Geert
diff mbox series

Patch

diff --git a/net/rxrpc/output.c b/net/rxrpc/output.c
index 004c762c2e8d..6f2b4fb4b0aa 100644
--- a/net/rxrpc/output.c
+++ b/net/rxrpc/output.c
@@ -523,6 +523,9 @@  int rxrpc_send_data_packet(struct rxrpc_call *call, struct sk_buff *skb,
 		}
 		break;
 #endif
+
+	default:
+		BUG();
 	}
 
 	if (ret < 0)