net/xfrm: Use an IS_ERR test rather than a NULL test
Julien Brunel [Wed, 3 Sep 2008 00:24:28 +0000 (17:24 -0700)]
In case of error, the function xfrm_bundle_create returns an ERR
pointer, but never returns a NULL pointer. So a NULL test that comes
after an IS_ERR test should be deleted.

The semantic match that finds this problem is as follows:
(http://www.emn.fr/x-info/coccinelle/)

// <smpl>
@match_bad_null_test@
expression x, E;
statement S1,S2;
@@
x =  xfrm_bundle_create(...)
... when != x = E
*  if (x != NULL)
S1 else S2
// </smpl>

Signed-off-by: Julien Brunel <brunel@diku.dk>
Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/xfrm/xfrm_policy.c

index 841b32a..46914b7 100644 (file)
@@ -1731,8 +1731,7 @@ restart:
                         * We can't enlist stable bundles either.
                         */
                        write_unlock_bh(&policy->lock);
-                       if (dst)
-                               dst_free(dst);
+                       dst_free(dst);
 
                        if (pol_dead)
                                XFRM_INC_STATS(LINUX_MIB_XFRMOUTPOLDEAD);
@@ -1748,8 +1747,7 @@ restart:
                        err = xfrm_dst_update_origin(dst, fl);
                if (unlikely(err)) {
                        write_unlock_bh(&policy->lock);
-                       if (dst)
-                               dst_free(dst);
+                       dst_free(dst);
                        XFRM_INC_STATS(LINUX_MIB_XFRMOUTBUNDLECHECKERROR);
                        goto error;
                }