From 80688afb9c35b3934ce2d6be9973758915e2e0ef Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Horia=20Geant=C4=83?= Date: Tue, 17 Mar 2026 12:25:14 +0200 Subject: [PATCH] crypto: caam - fix overflow on long hmac keys MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit When a key longer than block size is supplied, it is copied and then hashed into the real key. The memory allocated for the copy needs to be rounded to DMA cache alignment, as otherwise the hashed key may corrupt neighbouring memory. The copying is performed using kmemdup, however this leads to an overflow: reading more bytes (aligned_len - keylen) from the keylen source buffer. Fix this by replacing kmemdup with kmalloc, followed by memcpy. Fixes: 199354d7fb6e ("crypto: caam - Remove GFP_DMA and add DMA alignment padding") Signed-off-by: Horia Geantă Signed-off-by: Herbert Xu --- drivers/crypto/caam/caamalg_qi2.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/crypto/caam/caamalg_qi2.c b/drivers/crypto/caam/caamalg_qi2.c index 167372936ca7..78964e1712e5 100644 --- a/drivers/crypto/caam/caamalg_qi2.c +++ b/drivers/crypto/caam/caamalg_qi2.c @@ -3326,9 +3326,10 @@ static int ahash_setkey(struct crypto_ahash *ahash, const u8 *key, if (aligned_len < keylen) return -EOVERFLOW; - hashed_key = kmemdup(key, aligned_len, GFP_KERNEL); + hashed_key = kmalloc(aligned_len, GFP_KERNEL); if (!hashed_key) return -ENOMEM; + memcpy(hashed_key, key, keylen); ret = hash_digest_key(ctx, &keylen, hashed_key, digestsize); if (ret) goto bad_free_key;