diff options
author | Gustavo A. R. Silva <gustavo@embeddedor.com> | 2020-02-24 19:17:09 -0600 |
---|---|---|
committer | Kalle Valo <kvalo@codeaurora.org> | 2020-03-23 19:00:31 +0200 |
commit | c5047d5b831bb5f4dfa22230a2f64794ed20ea82 (patch) | |
tree | 66004192ca7aa6444dc79216f0d65aa942efa134 /drivers/net/wireless/marvell/libertas/host.h | |
parent | 645aa87fdfd9e608faba215677d92de9dba6dc22 (diff) |
libertas: 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: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20200225011709.GA601@embeddedor
Diffstat (limited to 'drivers/net/wireless/marvell/libertas/host.h')
-rw-r--r-- | drivers/net/wireless/marvell/libertas/host.h | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/drivers/net/wireless/marvell/libertas/host.h b/drivers/net/wireless/marvell/libertas/host.h index a4fc3f79bb17..dfa22468b14a 100644 --- a/drivers/net/wireless/marvell/libertas/host.h +++ b/drivers/net/wireless/marvell/libertas/host.h @@ -461,7 +461,7 @@ struct cmd_ds_802_11_scan { uint8_t bsstype; uint8_t bssid[ETH_ALEN]; - uint8_t tlvbuffer[0]; + uint8_t tlvbuffer[]; } __packed; struct cmd_ds_802_11_scan_rsp { @@ -469,7 +469,7 @@ struct cmd_ds_802_11_scan_rsp { __le16 bssdescriptsize; uint8_t nr_sets; - uint8_t bssdesc_and_tlvbuffer[0]; + uint8_t bssdesc_and_tlvbuffer[]; } __packed; struct cmd_ds_802_11_get_log { |