path: root/include/uapi/linux/netfilter_bridge
diff options
authorGustavo A. R. Silva <gustavo@embeddedor.com>2020-02-20 07:59:14 -0600
committerPablo Neira Ayuso <pablo@netfilter.org>2020-03-15 15:20:16 +0100
commit6daf14140129d30207ed6a0a69851fa6a3636bda (patch)
tree43f5f5d662db9cfc241ba1c848f17694b95a16ff /include/uapi/linux/netfilter_bridge
parentnetfilter: nft_set_pipapo: make the symbol 'nft_pipapo_get' static (diff)
netfilter: Replace zero-length array with flexible-array member
The current codebase makes use of the zero-length array language extension to the C90 standard, but the preferred mechanism to declare variable-length types such as these ones is a flexible array member[1][2], introduced in C99: struct foo { int stuff; struct boo array[]; }; By making use of the mechanism above, we will get a compiler warning in case the flexible array does not occur last in the structure, which will help us prevent some kind of undefined behavior bugs from being inadvertently introduced[3] to the codebase from now on. Also, notice that, dynamic memory allocations won't be affected by this change: "Flexible array members have incomplete type, and so the sizeof operator may not be applied. As a quirk of the original implementation of zero-length arrays, sizeof evaluates to zero."[1] Lastly, fix checkpatch.pl warning WARNING: __aligned(size) is preferred over __attribute__((aligned(size))) in net/bridge/netfilter/ebtables.c This issue was found with the help of Coccinelle. [1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html [2] https://github.com/KSPP/linux/issues/21 [3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour") Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Diffstat (limited to 'include/uapi/linux/netfilter_bridge')
1 files changed, 1 insertions, 1 deletions
diff --git a/include/uapi/linux/netfilter_bridge/ebt_among.h b/include/uapi/linux/netfilter_bridge/ebt_among.h
index 9acf757bc1f7..73b26a280c4f 100644
--- a/include/uapi/linux/netfilter_bridge/ebt_among.h
+++ b/include/uapi/linux/netfilter_bridge/ebt_among.h
@@ -40,7 +40,7 @@ struct ebt_mac_wormhash_tuple {
struct ebt_mac_wormhash {
int table[257];
int poolsize;
- struct ebt_mac_wormhash_tuple pool[0];
+ struct ebt_mac_wormhash_tuple pool[];
#define ebt_mac_wormhash_size(x) ((x) ? sizeof(struct ebt_mac_wormhash) \