From a91d9346a70b68f77884cba9d9ec3b70f96bf9d2 Mon Sep 17 00:00:00 2001 From: ZhaoJinming Date: Wed, 23 Sep 2026 18:14:57 +0800 Subject: [PATCH] crypto: caam - fix double-free in caam_rsa_set_priv_key_form() caam_rsa_set_priv_key_form() frees the partially allocated key components (p, q, tmp1, tmp2, dp, dq) with kfree_sensitive() on its error path, but does not set those pointers to NULL afterward. When the function returns an error, caam_rsa_set_priv_key() jumps to its err label and calls caam_rsa_free_key(), which frees all of those same pointers again, resulting in a double-free. This is reachable when the allocation of q, tmp1, tmp2, dp, dq or qinv fails, e.g. under memory pressure, or for a malformed key whose CRT members decode to zero length and make caam_read_rsa_crt() return NULL. Set each pointer to NULL right after freeing it so that the subsequent caam_rsa_free_key() call becomes a no-op for the already-freed fields. Fixes: 52e26d77b8b3 ("crypto: caam - add support for RSA key form 2") Cc: stable@vger.kernel.org Signed-off-by: ZhaoJinming Reviewed-by: Sahil Malhotra Signed-off-by: Herbert Xu --- drivers/crypto/caam/caampkc.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/crypto/caam/caampkc.c b/drivers/crypto/caam/caampkc.c index cb001aa1de66..ac515ed8c575 100644 --- a/drivers/crypto/caam/caampkc.c +++ b/drivers/crypto/caam/caampkc.c @@ -1033,16 +1033,22 @@ static int caam_rsa_set_priv_key_form(struct caam_rsa_ctx *ctx, free_dq: kfree_sensitive(rsa_key->dq); + rsa_key->dq = NULL; free_dp: kfree_sensitive(rsa_key->dp); + rsa_key->dp = NULL; free_tmp2: kfree_sensitive(rsa_key->tmp2); + rsa_key->tmp2 = NULL; free_tmp1: kfree_sensitive(rsa_key->tmp1); + rsa_key->tmp1 = NULL; free_q: kfree_sensitive(rsa_key->q); + rsa_key->q = NULL; free_p: kfree_sensitive(rsa_key->p); + rsa_key->p = NULL; return -ENOMEM; }