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 | |
| 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')
| -rw-r--r-- | drivers/net/wireless/marvell/libertas/host.h | 4 | ||||
| -rw-r--r-- | drivers/net/wireless/marvell/libertas/if_sdio.c | 2 | ||||
| -rw-r--r-- | drivers/net/wireless/marvell/libertas/if_spi.c | 2 | ||||
| -rw-r--r-- | drivers/net/wireless/marvell/libertas/if_usb.h | 2 |
4 files changed, 5 insertions, 5 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 { diff --git a/drivers/net/wireless/marvell/libertas/if_sdio.c b/drivers/net/wireless/marvell/libertas/if_sdio.c index 30f1025ecb9b..acf61b93b782 100644 --- a/drivers/net/wireless/marvell/libertas/if_sdio.c +++ b/drivers/net/wireless/marvell/libertas/if_sdio.c @@ -103,7 +103,7 @@ MODULE_FIRMWARE("sd8688.bin"); struct if_sdio_packet { struct if_sdio_packet *next; u16 nb; - u8 buffer[0] __attribute__((aligned(4))); + u8 buffer[] __aligned(4); }; struct if_sdio_card { diff --git a/drivers/net/wireless/marvell/libertas/if_spi.c b/drivers/net/wireless/marvell/libertas/if_spi.c index 3c3f266bf116..cd9f8ecf171f 100644 --- a/drivers/net/wireless/marvell/libertas/if_spi.c +++ b/drivers/net/wireless/marvell/libertas/if_spi.c @@ -35,7 +35,7 @@ struct if_spi_packet { struct list_head list; u16 blen; - u8 buffer[0] __attribute__((aligned(4))); + u8 buffer[] __aligned(4); }; struct if_spi_card { diff --git a/drivers/net/wireless/marvell/libertas/if_usb.h b/drivers/net/wireless/marvell/libertas/if_usb.h index 8dc14bec3e16..7d0daeb33c3f 100644 --- a/drivers/net/wireless/marvell/libertas/if_usb.h +++ b/drivers/net/wireless/marvell/libertas/if_usb.h @@ -91,7 +91,7 @@ struct fwheader { struct fwdata { struct fwheader hdr; __le32 seqnum; - uint8_t data[0]; + uint8_t data[]; }; /* fwsyncheader */ |