Commit 5224f790 authored by Gustavo A. R. Silva's avatar Gustavo A. R. Silva
Browse files

treewide: Replace zero-length arrays with flexible-array members 

There is a regular need in the kernel to provide a way to declare
having a dynamically sized set of trailing elements in a structure.
Kernel code should always use “flexible array members”[1] for these
cases. The older style of one-element or zero-length arrays should
no longer be used[2].

This code was transformed with the help of Coccinelle:
(next-20220214$ spatch --jobs $(getconf _NPROCESSORS_ONLN) --sp-file script.cocci --include-headers --dir . > output.patch)

@@
identifier S, member, array;
type T1, T2;
@@

struct S {
  ...
  T1 member;
  T2 array[
- 0
  ];
};

UAPI and wireless changes were intentionally excluded from this patch
and will be sent out separately.

[1] https://en.wikipedia.org/wiki/Flexible_array_member
[2] https://www.kernel.org/doc/html/v5.16/process/deprecated.html#zero-length-and-one-element-arrays

Link: https://github.com/KSPP/linux/issues/78


Reviewed-by: default avatarKees Cook <keescook@chromium.org>
Signed-off-by: default avatarGustavo A. R. Silva <gustavoars@kernel.org>
parent 26291c54

arch/alpha/include/asm/hwrpb.h

+1 −1
Original line number Diff line number Diff line
@@ -152,7 +152,7 @@ struct memdesc_struct { 
	unsigned long chksum;

	unsigned long optional_pa;

	unsigned long numclusters;

	struct memclust_struct cluster[0];

	struct memclust_struct cluster[];

};



struct dsr_struct {

arch/ia64/include/asm/sal.h

+1 −1
Original line number Diff line number Diff line
@@ -420,7 +420,7 @@ typedef struct sal_log_processor_info { 
	 * The rest of this structure consists of variable-length arrays, which can't be

	 * expressed in C.

	 */

	sal_log_mod_error_info_t info[0];

	sal_log_mod_error_info_t info[];

	/*

	 * This is what the rest looked like if C supported variable-length arrays:

	 *

arch/s390/include/asm/ccwgroup.h

+1 −1
Original line number Diff line number Diff line
@@ -25,7 +25,7 @@ struct ccwgroup_device { 
	unsigned int count;

	struct device	dev;

	struct work_struct ungroup_work;

	struct ccw_device *cdev[0];

	struct ccw_device *cdev[];

};



/**

arch/s390/include/asm/chsc.h

+1 −1
Original line number Diff line number Diff line
@@ -63,7 +63,7 @@ struct chsc_pnso_area { 
	struct chsc_header response;

	u32:32;

	struct chsc_pnso_naihdr naihdr;

	struct chsc_pnso_naid_l2 entries[0];

	struct chsc_pnso_naid_l2 entries[];

} __packed __aligned(PAGE_SIZE);



#endif /* _ASM_S390_CHSC_H */

arch/s390/include/asm/eadm.h

+1 −1
Original line number Diff line number Diff line
@@ -78,7 +78,7 @@ struct aob { 


struct aob_rq_header {

	struct scm_device *scmdev;

	char data[0];

	char data[];

};



struct scm_device {