[PATCH v2] crypto: ecc - Streamline alloc_point and remove {alloc,free}_digits_space

From: Thorsten Blum
Date: Mon Jan 05 2026 - 17:23:45 EST


Check 'ndigits' before allocating 'struct ecc_point' to return early if
needed. Inline the code from and remove ecc_alloc_digits_space() and
ecc_free_digits_space(), respectively.

Signed-off-by: Thorsten Blum <thorsten.blum@xxxxxxxxx>
---
Changes in v2:
- Use kfree() instead of kfree_sensitive() as suggested by Stefan
- Link to v1: https://lore.kernel.org/lkml/20251218212713.1616-2-thorsten.blum@xxxxxxxxx/
---
crypto/ecc.c | 27 +++++++++------------------
1 file changed, 9 insertions(+), 18 deletions(-)

diff --git a/crypto/ecc.c b/crypto/ecc.c
index 6cf9a945fc6c..2808b3d5f483 100644
--- a/crypto/ecc.c
+++ b/crypto/ecc.c
@@ -90,33 +90,24 @@ void ecc_digits_from_bytes(const u8 *in, unsigned int nbytes,
}
EXPORT_SYMBOL(ecc_digits_from_bytes);

-static u64 *ecc_alloc_digits_space(unsigned int ndigits)
+struct ecc_point *ecc_alloc_point(unsigned int ndigits)
{
- size_t len = ndigits * sizeof(u64);
+ struct ecc_point *p;
+ size_t ndigits_sz;

- if (!len)
+ if (!ndigits)
return NULL;

- return kmalloc(len, GFP_KERNEL);
-}
-
-static void ecc_free_digits_space(u64 *space)
-{
- kfree_sensitive(space);
-}
-
-struct ecc_point *ecc_alloc_point(unsigned int ndigits)
-{
- struct ecc_point *p = kmalloc(sizeof(*p), GFP_KERNEL);
-
+ p = kmalloc(sizeof(*p), GFP_KERNEL);
if (!p)
return NULL;

- p->x = ecc_alloc_digits_space(ndigits);
+ ndigits_sz = ndigits * sizeof(u64);
+ p->x = kmalloc(ndigits_sz, GFP_KERNEL);
if (!p->x)
goto err_alloc_x;

- p->y = ecc_alloc_digits_space(ndigits);
+ p->y = kmalloc(ndigits_sz, GFP_KERNEL);
if (!p->y)
goto err_alloc_y;

@@ -125,7 +116,7 @@ struct ecc_point *ecc_alloc_point(unsigned int ndigits)
return p;

err_alloc_y:
- ecc_free_digits_space(p->x);
+ kfree(p->x);
err_alloc_x:
kfree(p);
return NULL;
--
Thorsten Blum <thorsten.blum@xxxxxxxxx>
GPG: 1D60 735E 8AEF 3BE4 73B6 9D84 7336 78FD 8DFE EAD4