[ Upstream commit 76497732932f15e7323dc805e8ea8dc11bb587cf ]
The use of zero-sized array causes undefined behaviour when it is not the last member in a structure. As it happens to be in this case.
Also, the current code makes use of a language extension to the C90 standard, but the preferred mechanism to declare variable-length types such as this one is a flexible array member, 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. Which is beneficial to cultivate a high-quality code.
Fixes: e48f129c2f20 ("[SCSI] cxgb3i: convert cdev->l2opt to use rcu to prevent NULL dereference") Signed-off-by: Gustavo A. R. Silva gustavo@embeddedor.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/ethernet/chelsio/cxgb3/l2t.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/net/ethernet/chelsio/cxgb3/l2t.h b/drivers/net/ethernet/chelsio/cxgb3/l2t.h index c2fd323c40782..ea75f275023ff 100644 --- a/drivers/net/ethernet/chelsio/cxgb3/l2t.h +++ b/drivers/net/ethernet/chelsio/cxgb3/l2t.h @@ -75,8 +75,8 @@ struct l2t_data { struct l2t_entry *rover; /* starting point for next allocation */ atomic_t nfree; /* number of free entries */ rwlock_t lock; - struct l2t_entry l2tab[0]; struct rcu_head rcu_head; /* to handle rcu cleanup */ + struct l2t_entry l2tab[]; };
typedef void (*arp_failure_handler_func)(struct t3cdev * dev,