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23 October 2021, 00:29:24 UTC
Revision e76018cb604ace486de9cf85898c14bb2b47faff authored by Gustavo A. R. Silva on 23 March 2020, 21:48:10 UTC, committed by Gustavo A. R. Silva on 18 April 2020, 20:44:54 UTC 
can: dev: peak_canfd.h: 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>
1 parent 5a58ec8
Raw File
Tip revision: e76018cb604ace486de9cf85898c14bb2b47faff authored by Gustavo A. R. Silva on 23 March 2020, 21:48:10 UTC
can: dev: peak_canfd.h: Replace zero-length array with flexible-array member
Tip revision: e76018c
netns.h 
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __SUNRPC_NETNS_H__
#define __SUNRPC_NETNS_H__

#include <net/net_namespace.h>
#include <net/netns/generic.h>

struct cache_detail;

struct sunrpc_net {
	struct proc_dir_entry *proc_net_rpc;
	struct cache_detail *ip_map_cache;
	struct cache_detail *unix_gid_cache;
	struct cache_detail *rsc_cache;
	struct cache_detail *rsi_cache;

	struct super_block *pipefs_sb;
	struct rpc_pipe *gssd_dummy;
	struct mutex pipefs_sb_lock;

	struct list_head all_clients;
	spinlock_t rpc_client_lock;

	struct rpc_clnt *rpcb_local_clnt;
	struct rpc_clnt *rpcb_local_clnt4;
	spinlock_t rpcb_clnt_lock;
	unsigned int rpcb_users;
	unsigned int rpcb_is_af_local : 1;

	struct mutex gssp_lock;
	struct rpc_clnt *gssp_clnt;
	int use_gss_proxy;
	int pipe_version;
	atomic_t pipe_users;
	struct proc_dir_entry *use_gssp_proc;
};

extern unsigned int sunrpc_net_id;

int ip_map_cache_create(struct net *);
void ip_map_cache_destroy(struct net *);

#endif
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