diff options
| author |   Gustavo A. R. Silva <gustavo@embeddedor.com> | 2020-02-24 18:12:13 -0600 |
|---|---|---|
| committer |   David S. Miller <davem@davemloft.net> | 2020-02-26 16:43:09 -0800 |
| commit | 274ac2831a8b1fd54de476979da6bd8f38d4cb5d (patch) | |
| tree | 655d9054e0d3f38162dfef02ee8c2409e0a2b134 /drivers/net | |
| parent | net: hns: Replace zero-length array with flexible-array member (diff) | |
| download | linux-dev-274ac2831a8b1fd54de476979da6bd8f38d4cb5d.tar.xz linux-dev-274ac2831a8b1fd54de476979da6bd8f38d4cb5d.zip | |
net: marvell: 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]
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: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/net')
| -rw-r--r-- | drivers/net/ethernet/marvell/skge.h | 2 | ||||
| -rw-r--r-- | drivers/net/ethernet/marvell/sky2.h | 2 |
2 files changed, 2 insertions, 2 deletions
diff --git a/drivers/net/ethernet/marvell/skge.h b/drivers/net/ethernet/marvell/skge.h index 6fa7b6a34c08..a1313d57e283 100644 --- a/drivers/net/ethernet/marvell/skge.h +++ b/drivers/net/ethernet/marvell/skge.h @@ -2426,7 +2426,7 @@ struct skge_hw { spinlock_t phy_lock; struct tasklet_struct phy_task; - char irq_name[0]; /* skge@pci:000:04:00.0 */ + char irq_name[]; /* skge@pci:000:04:00.0 */ }; enum pause_control { diff --git a/drivers/net/ethernet/marvell/sky2.h b/drivers/net/ethernet/marvell/sky2.h index b02b6523083c..ada1ca60f088 100644 --- a/drivers/net/ethernet/marvell/sky2.h +++ b/drivers/net/ethernet/marvell/sky2.h @@ -2309,7 +2309,7 @@ struct sky2_hw { struct work_struct restart_work; wait_queue_head_t msi_wait; - char irq_name[0]; + char irq_name[]; }; static inline int sky2_is_copper(const struct sky2_hw *hw) |