mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-12-21 10:05:00 +08:00
84c1e51d7d
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]
sizeof(flexible-array-member) triggers a warning because flexible array
members have incomplete type[1]. There are some instances of code in
which the sizeof operator is being incorrectly/erroneously applied to
zero-length arrays and the result is zero. Such instances may be hiding
some bugs. So, this work (flexible-array member conversions) will also
help to get completely rid of those sorts of issues.
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 7649773293 ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/20200507185318.GA14393@embeddedor
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
64 lines
1.3 KiB
C
64 lines
1.3 KiB
C
/* SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause) */
|
|
/*
|
|
* Copyright(c) 2016 Google Inc. All rights reserved.
|
|
* Copyright(c) 2016 Linaro Ltd. All rights reserved.
|
|
*/
|
|
|
|
#ifndef __ARPC_H
|
|
#define __ARPC_H
|
|
|
|
/* APBridgeA RPC (ARPC) */
|
|
|
|
enum arpc_result {
|
|
ARPC_SUCCESS = 0x00,
|
|
ARPC_NO_MEMORY = 0x01,
|
|
ARPC_INVALID = 0x02,
|
|
ARPC_TIMEOUT = 0x03,
|
|
ARPC_UNKNOWN_ERROR = 0xff,
|
|
};
|
|
|
|
struct arpc_request_message {
|
|
__le16 id; /* RPC unique id */
|
|
__le16 size; /* Size in bytes of header + payload */
|
|
__u8 type; /* RPC type */
|
|
__u8 data[]; /* ARPC data */
|
|
} __packed;
|
|
|
|
struct arpc_response_message {
|
|
__le16 id; /* RPC unique id */
|
|
__u8 result; /* Result of RPC */
|
|
} __packed;
|
|
|
|
/* ARPC requests */
|
|
#define ARPC_TYPE_CPORT_CONNECTED 0x01
|
|
#define ARPC_TYPE_CPORT_QUIESCE 0x02
|
|
#define ARPC_TYPE_CPORT_CLEAR 0x03
|
|
#define ARPC_TYPE_CPORT_FLUSH 0x04
|
|
#define ARPC_TYPE_CPORT_SHUTDOWN 0x05
|
|
|
|
struct arpc_cport_connected_req {
|
|
__le16 cport_id;
|
|
} __packed;
|
|
|
|
struct arpc_cport_quiesce_req {
|
|
__le16 cport_id;
|
|
__le16 peer_space;
|
|
__le16 timeout;
|
|
} __packed;
|
|
|
|
struct arpc_cport_clear_req {
|
|
__le16 cport_id;
|
|
} __packed;
|
|
|
|
struct arpc_cport_flush_req {
|
|
__le16 cport_id;
|
|
} __packed;
|
|
|
|
struct arpc_cport_shutdown_req {
|
|
__le16 cport_id;
|
|
__le16 timeout;
|
|
__u8 phase;
|
|
} __packed;
|
|
|
|
#endif /* __ARPC_H */
|