On 3/6/24 01:36, Amir Goldstein wrote:
On Wed, Mar 6, 2024 at 1:52 AM Kees Cook <keescook@xxxxxxxxxxxx> wrote:
On Tue, Mar 05, 2024 at 04:18:46PM -0600, Gustavo A. R. Silva wrote:
-Wflex-array-member-not-at-end is coming in GCC-14, and we are getting
ready to enable it globally.
There is currently a local structure `f` that is using a flexible
`struct file_handle` as header for an on-stack place-holder for the
flexible-array member `unsigned char f_handle[];`.
struct {
struct file_handle handle;
u8 pad[MAX_HANDLE_SZ];
} f;
This code pattern is "put a flex array struct on the stack", but we have
a macro for this now:
DEFINE_FLEX(struct file_handle, handle, f_handle, MAX_HANDLE_SZ);
And you can even include the initializer:
_DEFINE_FLEX(struct file_handle, handle, f_handle, MAX_HANDLE_SZ,
= { .handle_bytes = MAX_HANDLE_SZ });
Indeed that looks much nicer.
Yeah, I'll probably wait for this to land before I send a v2:
https://lore.kernel.org/linux-hardening/20240306010746.work.678-kees@xxxxxxxxxx/
Thanks
--
Gustavo
