Aprove: M_ZERO cyg_net_malloc flag

Aprove: M_ZERO cyg_net_malloc flag

[Andrew Lunn]

Aprovel request for the 2.0 branch:

Name: M_ZERO flag for cyg_net_malloc()

Purpose: The bsd_tcpip MALLOC macro can pass the flag
M_ZERO. cyg_net_malloc ignores this so leaving random junk in the
memory returned. This can then cause calls like getpeername and
getsockname to return sockaddr with junk in there tails. When such a
sockaddr is then passed back into the stack with a bind call, the bind
fails because of the junk.

Risk: Small.

Affected packages: bsd_tcpip and anything depending on it.

         Andrew

Index: packages/net/bsd_tcpip//current/ChangeLog
===================================================================
RCS file: /cvs/ecos/ecos-opt/net/net/bsd_tcpip/current/ChangeLog,v
retrieving revision 1.17.2.1
diff -u -r1.17.2.1 ChangeLog
--- packages/net/bsd_tcpip//current/ChangeLog   14 Mar 2003 13:44:37 -0000     1.17.2.1
+++ packages/net/bsd_tcpip//current/ChangeLog   29 Apr 2003 07:46:10 -0000
@@ -1,3 +1,8 @@
+2003-04-29  Andrew Lunn  <andrew.lunn@ascom.ch>
+
+       * src/ecos/support.c (cyg_net_malloc): Honour the M_ZERO
+       flag. Otherwise we get random junk in places we don't want it.
+
 2003-03-14  Andrew Lunn  <andrew.lunn@ascom.ch>
 
        * src/sys/net/if.c (if_attach): Removed printf which causes the
Index: packages/net/bsd_tcpip//current/src/ecos/support.c
===================================================================
RCS file: /cvs/ecos/ecos-opt/net/net/bsd_tcpip/current/src/ecos/support.c,v
retrieving revision 1.4
diff -u -r1.4 support.c
--- packages/net/bsd_tcpip//current/src/ecos/support.c  3 Dec 2002 17:22:46 -0000       1.4
+++ packages/net/bsd_tcpip//current/src/ecos/support.c  29 Apr 2003 07:46:11 -0000
@@ -201,6 +201,9 @@
     } else {
         res = cyg_mempool_var_alloc(net_mem, size);
     }
+    if ((flags & M_ZERO) && res) {
+      memset(res,0,size);
+    }
     FINISH_STATS(stats_malloc);
     log(LOG_MDEBUG, "%p\n", res);
     return (res);

Re: Aprove: M_ZERO cyg_net_malloc flag

[Gary Thomas]

On Tue, 2003-04-29 at 01:51, Andrew Lunn wrote:
> Aprovel request for the 2.0 branch:
> 
> Name: M_ZERO flag for cyg_net_malloc()
> 
> Purpose: The bsd_tcpip MALLOC macro can pass the flag
> M_ZERO. cyg_net_malloc ignores this so leaving random junk in the
> memory returned. This can then cause calls like getpeername and
> getsockname to return sockaddr with junk in there tails. When such a
> sockaddr is then passed back into the stack with a bind call, the bind
> fails because of the junk.
> 
> Risk: Small.
> 
> Affected packages: bsd_tcpip and anything depending on it.
> 

Looks fine to me.  Please go ahead and apply this change.

>          Andrew
> 
> Index: packages/net/bsd_tcpip//current/ChangeLog
> ===================================================================
> RCS file: /cvs/ecos/ecos-opt/net/net/bsd_tcpip/current/ChangeLog,v
> retrieving revision 1.17.2.1
> diff -u -r1.17.2.1 ChangeLog
> --- packages/net/bsd_tcpip//current/ChangeLog   14 Mar 2003 13:44:37 -0000     1.17.2.1
> +++ packages/net/bsd_tcpip//current/ChangeLog   29 Apr 2003 07:46:10 -0000
> @@ -1,3 +1,8 @@
> +2003-04-29  Andrew Lunn  <andrew.lunn@ascom.ch>
> +
> +       * src/ecos/support.c (cyg_net_malloc): Honour the M_ZERO
> +       flag. Otherwise we get random junk in places we don't want it.
> +
>  2003-03-14  Andrew Lunn  <andrew.lunn@ascom.ch>
>  
>         * src/sys/net/if.c (if_attach): Removed printf which causes the
> Index: packages/net/bsd_tcpip//current/src/ecos/support.c
> ===================================================================
> RCS file: /cvs/ecos/ecos-opt/net/net/bsd_tcpip/current/src/ecos/support.c,v
> retrieving revision 1.4
> diff -u -r1.4 support.c
> --- packages/net/bsd_tcpip//current/src/ecos/support.c  3 Dec 2002 17:22:46 -0000       1.4
> +++ packages/net/bsd_tcpip//current/src/ecos/support.c  29 Apr 2003 07:46:11 -0000
> @@ -201,6 +201,9 @@
>      } else {
>          res = cyg_mempool_var_alloc(net_mem, size);
>      }
> +    if ((flags & M_ZERO) && res) {
> +      memset(res,0,size);
> +    }
>      FINISH_STATS(stats_malloc);
>      log(LOG_MDEBUG, "%p\n", res);
>      return (res);

-- 
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