From f75f66683ded09f7135aef2e763c245a07c8271a Mon Sep 17 00:00:00 2001 From: Dan Moulding Date: Mon, 8 Sep 2025 10:12:43 -0600 Subject: crypto: comp - Use same definition of context alloc and free ops In commit 42d9f6c77479 ("crypto: acomp - Move scomp stream allocation code into acomp"), the crypto_acomp_streams struct was made to rely on having the alloc_ctx and free_ctx operations defined in the same order as the scomp_alg struct. But in that same commit, the alloc_ctx and free_ctx members of scomp_alg may be randomized by structure layout randomization, since they are contained in a pure ops structure (containing only function pointers). If the pointers within scomp_alg are randomized, but those in crypto_acomp_streams are not, then the order may no longer match. This fixes the problem by removing the union from scomp_alg so that both crypto_acomp_streams and scomp_alg will share the same definition of alloc_ctx and free_ctx, ensuring they will always have the same layout. Signed-off-by: Dan Moulding Suggested-by: Herbert Xu Fixes: 42d9f6c77479 ("crypto: acomp - Move scomp stream allocation code into acomp") Signed-off-by: Herbert Xu --- include/crypto/internal/scompress.h | 11 +---------- 1 file changed, 1 insertion(+), 10 deletions(-) (limited to 'include') diff --git a/include/crypto/internal/scompress.h b/include/crypto/internal/scompress.h index 533d6c16a491..6a2c5f2e90f9 100644 --- a/include/crypto/internal/scompress.h +++ b/include/crypto/internal/scompress.h @@ -18,11 +18,8 @@ struct crypto_scomp { /** * struct scomp_alg - synchronous compression algorithm * - * @alloc_ctx: Function allocates algorithm specific context - * @free_ctx: Function frees context allocated with alloc_ctx * @compress: Function performs a compress operation * @decompress: Function performs a de-compress operation - * @base: Common crypto API algorithm data structure * @streams: Per-cpu memory for algorithm * @calg: Cmonn algorithm data structure shared with acomp */ @@ -34,13 +31,7 @@ struct scomp_alg { unsigned int slen, u8 *dst, unsigned int *dlen, void *ctx); - union { - struct { - void *(*alloc_ctx)(void); - void (*free_ctx)(void *ctx); - }; - struct crypto_acomp_streams streams; - }; + struct crypto_acomp_streams streams; union { struct COMP_ALG_COMMON; -- cgit v1.2.3