diff options
| author | Gustavo A. R. Silva <gustavo@embeddedor.com> | 2020-02-13 16:57:00 -0800 |
|---|---|---|
| committer | Dmitry Torokhov <dmitry.torokhov@gmail.com> | 2020-02-13 17:09:47 -0800 |
| commit | a1b9b65edfd8f195dafaebf68f7d321eb9b3ab82 (patch) | |
| tree | 34fe042c28be17515b9c279be642462cdc29067b | |
| parent | cfb8d7811f815d17babadd87436300261fd54de7 (diff) | |
Input: gpio_keys - 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>
Link: https://lore.kernel.org/r/20200213002600.GA31916@embeddedor.com
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
| -rw-r--r-- | drivers/input/keyboard/gpio_keys.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/input/keyboard/gpio_keys.c b/drivers/input/keyboard/gpio_keys.c index 1f56d53454b2..53c9ff338dea 100644 --- a/drivers/input/keyboard/gpio_keys.c +++ b/drivers/input/keyboard/gpio_keys.c @@ -55,7 +55,7 @@ struct gpio_keys_drvdata { struct input_dev *input; struct mutex disable_lock; unsigned short *keymap; - struct gpio_button_data data[0]; + struct gpio_button_data data[]; }; /* |