On Mon 23-09-24 23:38:05, Thorsten Blum wrote:
> Add the __counted_by compiler attribute to the flexible array member
> a_entries to improve access bounds-checking via CONFIG_UBSAN_BOUNDS and
> CONFIG_FORTIFY_SOURCE.
>
> Use struct_size() to calculate the number of bytes to allocate for new
> and cloned acls and remove the local size variables.
>
> Change the posix_acl_alloc() function parameter count from int to
> unsigned int to match posix_acl's a_count data type. Add identifier
> names to the function definition to silence two checkpatch warnings.
>
> Signed-off-by: Thorsten Blum <thorsten.blum@xxxxxxxxx>
Looks good. Feel free to add:
Reviewed-by: Jan Kara <jack@xxxxxxx>
Honza
> ---
> fs/posix_acl.c | 13 ++++++-------
> include/linux/posix_acl.h | 4 ++--
> 2 files changed, 8 insertions(+), 9 deletions(-)
>
> diff --git a/fs/posix_acl.c b/fs/posix_acl.c
> index 6c66a37522d0..4050942ab52f 100644
> --- a/fs/posix_acl.c
> +++ b/fs/posix_acl.c
> @@ -200,11 +200,11 @@ EXPORT_SYMBOL(posix_acl_init);
> * Allocate a new ACL with the specified number of entries.
> */
> struct posix_acl *
> -posix_acl_alloc(int count, gfp_t flags)
> +posix_acl_alloc(unsigned int count, gfp_t flags)
> {
> - const size_t size = sizeof(struct posix_acl) +
> - count * sizeof(struct posix_acl_entry);
> - struct posix_acl *acl = kmalloc(size, flags);
> + struct posix_acl *acl;
> +
> + acl = kmalloc(struct_size(acl, a_entries, count), flags);
> if (acl)
> posix_acl_init(acl, count);
> return acl;
> @@ -220,9 +220,8 @@ posix_acl_clone(const struct posix_acl *acl, gfp_t flags)
> struct posix_acl *clone = NULL;
>
> if (acl) {
> - int size = sizeof(struct posix_acl) + acl->a_count *
> - sizeof(struct posix_acl_entry);
> - clone = kmemdup(acl, size, flags);
> + clone = kmemdup(acl, struct_size(acl, a_entries, acl->a_count),
> + flags);
> if (clone)
> refcount_set(&clone->a_refcount, 1);
> }
> diff --git a/include/linux/posix_acl.h b/include/linux/posix_acl.h
> index 0e65b3d634d9..83b2c5fba1d9 100644
> --- a/include/linux/posix_acl.h
> +++ b/include/linux/posix_acl.h
> @@ -30,7 +30,7 @@ struct posix_acl {
> refcount_t a_refcount;
> struct rcu_head a_rcu;
> unsigned int a_count;
> - struct posix_acl_entry a_entries[];
> + struct posix_acl_entry a_entries[] __counted_by(a_count);
> };
>
> #define FOREACH_ACL_ENTRY(pa, acl, pe) \
> @@ -62,7 +62,7 @@ posix_acl_release(struct posix_acl *acl)
> /* posix_acl.c */
>
> extern void posix_acl_init(struct posix_acl *, int);
> -extern struct posix_acl *posix_acl_alloc(int, gfp_t);
> +extern struct posix_acl *posix_acl_alloc(unsigned int count, gfp_t flags);
> extern struct posix_acl *posix_acl_from_mode(umode_t, gfp_t);
> extern int posix_acl_equiv_mode(const struct posix_acl *, umode_t *);
> extern int __posix_acl_create(struct posix_acl **, gfp_t, umode_t *);
> --
> 2.46.1
>
--
Jan Kara <jack@xxxxxxxx>
SUSE Labs, CR
