diff options
| author | Gustavo A. R. Silva <gustavo@embeddedor.com> | 2020-02-12 22:28:07 +0300 |
|---|---|---|
| committer | Marcel Holtmann <marcel@holtmann.org> | 2020-02-13 10:28:38 +0300 |
| commit | 683cc86d812cace1ead68c489a52a1533498302c (patch) | |
| tree | 099b24909f915cdae35f29a053a1272f627cf910 /drivers/bluetooth/btintel.c | |
| parent | eb3939e386ec8df6049697d388298590231ac79c (diff) | |
| download | linux-683cc86d812cace1ead68c489a52a1533498302c.tar.xz | |
Bluetooth: btintel: 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
inadvertenly 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: Marcel Holtmann <marcel@holtmann.org>
Diffstat (limited to 'drivers/bluetooth/btintel.c')
| -rw-r--r-- | drivers/bluetooth/btintel.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/drivers/bluetooth/btintel.c b/drivers/bluetooth/btintel.c index 62e781a18bf0..6a0e2c5a8beb 100644 --- a/drivers/bluetooth/btintel.c +++ b/drivers/bluetooth/btintel.c @@ -376,13 +376,13 @@ struct ibt_cp_reg_access { __le32 addr; __u8 mode; __u8 len; - __u8 data[0]; + __u8 data[]; } __packed; struct ibt_rp_reg_access { __u8 status; __le32 addr; - __u8 data[0]; + __u8 data[]; } __packed; static int regmap_ibt_read(void *context, const void *addr, size_t reg_size, |