Am 14.02.2014 09:26, schrieb Dan Carpenter:
> This is a style question and not a real bug:
>
> Which is better:
>
> OPTION #1: ignore static checker warnings
>
> for (i = 0; i < ARRAY_SIZE(x); i++) {
> if (found)
> break;
> }
> x[i] = 0;
>
>
> OPTION #2: stop on the last element
>
> for (i = 0; i < ARRAY_SIZE(x) - 1; i++) {
> if (found)
> break;
> }
> x[i] = 0;
>
>
> OPTION #3: add a bogus error test
>
> for (i = 0; i < ARRAY_SIZE(x); i++) {
> if (found)
> break;
> }
> if (i == ARRAY_SIZE(x))
> return;
> x[i] = 0;
OPTION #3a
for (i = 0; i < ARRAY_SIZE(x); i++) {
if (found)
goto found;
}
return;
found:
x[i] = 0;
> OPTION #4: convoluted code
>
> for (i = 0; i < ARRAY_SIZE(x); i++) {
> if (!found)
> continue;
> x[i] = 0;
> break;
> }
>
> It's not clear to me what the right answer is...
i prefer a variation of #4
if (found) { x[i] = 0; break; }
reason:
1. ppl are bad with (!)
2. it is clear what happens if found
3. no side effects; i=ARRAY_SIZE(x) when nothing is found in loop
so using x[i] may cause trouble.
Of cause there is not THE answer in cases where {} is large
you need a different solution.
re,
wh
> regards,
> dan carpenter
>
> -----
>
> Hi Jon,
>
> FYI, there are new smatch warnings show up in
>
> tree: git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.git master
> head: d4f2fa6ad61ec1db713569a179183df4d0fc6ae7
> commit: 7d33939f475d403e79124e3143d7951dcfe8629f [96/108] tipc: delay delete of link when failover is needed
> :::::: branch date: 5 hours ago
> :::::: commit date: 5 hours ago
>
> net/tipc/node.c:258 tipc_node_detach_link() error: buffer overflow 'n_ptr->links' 2 <= 2
>
> git remote add net-next git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.git
> git remote update net-next
> git checkout 7d33939f475d403e79124e3143d7951dcfe8629f
> vim +258 net/tipc/node.c
>
> b97bf3fd Per Liden 2006-01-02 242
> a18c4bc3 Paul Gortmaker 2011-12-29 243 void tipc_node_attach_link(struct tipc_node *n_ptr, struct tipc_link *l_ptr)
> b97bf3fd Per Liden 2006-01-02 244 {
> 37b9c08a Allan Stephens 2011-02-28 245 n_ptr->links[l_ptr->b_ptr->identity] = l_ptr;
> 37b9c08a Allan Stephens 2011-02-28 246 atomic_inc(&tipc_num_links);
> 37b9c08a Allan Stephens 2011-02-28 247 n_ptr->link_cnt++;
> b97bf3fd Per Liden 2006-01-02 248 }
> b97bf3fd Per Liden 2006-01-02 249
> a18c4bc3 Paul Gortmaker 2011-12-29 250 void tipc_node_detach_link(struct tipc_node *n_ptr, struct tipc_link *l_ptr)
> b97bf3fd Per Liden 2006-01-02 251 {
> 7d33939f Jon Paul Maloy 2014-02-13 252 int i;
> 7d33939f Jon Paul Maloy 2014-02-13 253
> 7d33939f Jon Paul Maloy 2014-02-13 254 for (i = 0; i < MAX_BEARERS; i++) {
> 7d33939f Jon Paul Maloy 2014-02-13 255 if (l_ptr == n_ptr->links[i])
> 7d33939f Jon Paul Maloy 2014-02-13 256 break;
> 7d33939f Jon Paul Maloy 2014-02-13 257 }
> 7d33939f Jon Paul Maloy 2014-02-13 @258 n_ptr->links[i] = NULL;
> d1bcb115 Allan Stephens 2011-02-25 259 atomic_dec(&tipc_num_links);
> b97bf3fd Per Liden 2006-01-02 260 n_ptr->link_cnt--;
> b97bf3fd Per Liden 2006-01-02 261 }
> b97bf3fd Per Liden 2006-01-02 262
> 6c00055a David S. Miller 2008-09-02 263 static void node_established_contact(struct tipc_node *n_ptr)
> b97bf3fd Per Liden 2006-01-02 264 {
> 51a8e4de Allan Stephens 2010-12-31 265 tipc_k_signal((Handler)tipc_named_node_up, n_ptr->addr);
> c64f7a6a Jon Maloy 2012-11-16 266 n_ptr->bclink.oos_state = 0;
>
> ---
> 0-DAY kernel build testing backend Open Source Technology Center
> http://lists.01.org/mailman/listinfo/kbuild Intel Corporation
> --
> To unsubscribe from this list: send the line "unsubscribe kernel-janitors" in
> the body of a message to majordomo@xxxxxxxxxxxxxxx
> More majordomo info at http://vger.kernel.org/majordomo-info.html
>
--
To unsubscribe from this list: send the line "unsubscribe kernel-janitors" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
