On Tue, Mar 17, 2026 at 05:40:02PM -0600, Gustavo A. R. Silva wrote:
> struct nx842_crypto_header is declared with the __packed attribute,
> however the fields grouped with struct_group_tagged() were not packed.
> This caused the grouped header portion of the structure to lose the
> packed layout guarantees of the containing structure.
>
> Fix this by replacing struct_group_tagged() with __struct_group(...,
> ..., __packed, ...) so the grouped fields are packed, and the original
> layout is preserved, restoring the intended packed layout of the
> structure.
>
> Before changes:
> struct nx842_crypto_header {
> union {
> struct {
> __be16 magic; /* 0 2 */
> __be16 ignore; /* 2 2 */
> u8 groups; /* 4 1 */
> }; /* 0 6 */
> struct nx842_crypto_header_hdr hdr; /* 0 6 */
> }; /* 0 6 */
> struct nx842_crypto_header_group group[]; /* 6 0 */
>
> /* size: 6, cachelines: 1, members: 2 */
> /* last cacheline: 6 bytes */
> } __attribute__((__packed__));
>
> After changes:
> struct nx842_crypto_header {
> union {
> struct {
> __be16 magic; /* 0 2 */
> __be16 ignore; /* 2 2 */
> u8 groups; /* 4 1 */
> } __attribute__((__packed__)); /* 0 5 */
> struct nx842_crypto_header_hdr hdr; /* 0 5 */
> }; /* 0 5 */
> struct nx842_crypto_header_group group[]; /* 5 0 */
>
> /* size: 5, cachelines: 1, members: 2 */
> /* last cacheline: 5 bytes */
> } __attribute__((__packed__));
>
> Fixes: 1e6b251ce175 ("crypto: nx - Avoid -Wflex-array-member-not-at-end
> warning")
> Cc: [email protected]
> Signed-off-by: Gustavo A. R. Silva <[email protected]>
> ---
> drivers/crypto/nx/nx-842.h | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
Reviewed-by: Thorsten Blum <[email protected]>
