[PATCH crypto-next 06/23] x86/fpu: Remove VLA usage of skcipher
From: Kees Cook <hidden>
Date: 2018-09-19 02:12:50
Also in:
lkml
Subsystem:
the rest, x86 architecture (32-bit and 64-bit) · Maintainers:
Linus Torvalds, Thomas Gleixner, Ingo Molnar, Borislav Petkov, Dave Hansen
In the quest to remove all stack VLA usage from the kernel[1], this replaces struct crypto_skcipher and SKCIPHER_REQUEST_ON_STACK() usage with struct crypto_sync_skcipher and SYNC_SKCIPHER_REQUEST_ON_STACK(), which uses a fixed stack size. [1] https://lkml.kernel.org/r/CA+55aFzCG-zNmZwX4A2FQpadafLfEzK6CC=qPXydAacU1RqZWA@mail.gmail.com Cc: x86@kernel.org Signed-off-by: Kees Cook <redacted> --- arch/x86/crypto/fpu.c | 30 ++++++++++++++++-------------- 1 file changed, 16 insertions(+), 14 deletions(-)
diff --git a/arch/x86/crypto/fpu.c b/arch/x86/crypto/fpu.c
index 406680476c52..be9b3766f241 100644
--- a/arch/x86/crypto/fpu.c
+++ b/arch/x86/crypto/fpu.c@@ -20,21 +20,23 @@ #include <asm/fpu/api.h> struct crypto_fpu_ctx { - struct crypto_skcipher *child; + struct crypto_sync_skcipher *child; }; static int crypto_fpu_setkey(struct crypto_skcipher *parent, const u8 *key, unsigned int keylen) { struct crypto_fpu_ctx *ctx = crypto_skcipher_ctx(parent); - struct crypto_skcipher *child = ctx->child; + struct crypto_sync_skcipher *child = ctx->child; int err; - crypto_skcipher_clear_flags(child, CRYPTO_TFM_REQ_MASK); - crypto_skcipher_set_flags(child, crypto_skcipher_get_flags(parent) & + crypto_sync_skcipher_clear_flags(child, CRYPTO_TFM_REQ_MASK); + crypto_sync_skcipher_set_flags(child, + crypto_skcipher_get_flags(parent) & CRYPTO_TFM_REQ_MASK); - err = crypto_skcipher_setkey(child, key, keylen); - crypto_skcipher_set_flags(parent, crypto_skcipher_get_flags(child) & + err = crypto_sync_skcipher_setkey(child, key, keylen); + crypto_skcipher_set_flags(parent, + crypto_sync_skcipher_get_flags(child) & CRYPTO_TFM_RES_MASK); return err; }
@@ -43,11 +45,11 @@ static int crypto_fpu_encrypt(struct skcipher_request *req) { struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); struct crypto_fpu_ctx *ctx = crypto_skcipher_ctx(tfm); - struct crypto_skcipher *child = ctx->child; - SKCIPHER_REQUEST_ON_STACK(subreq, child); + struct crypto_sync_skcipher *child = ctx->child; + SYNC_SKCIPHER_REQUEST_ON_STACK(subreq, child); int err; - skcipher_request_set_tfm(subreq, child); + skcipher_request_set_sync_tfm(subreq, child); skcipher_request_set_callback(subreq, 0, NULL, NULL); skcipher_request_set_crypt(subreq, req->src, req->dst, req->cryptlen, req->iv);
@@ -64,11 +66,11 @@ static int crypto_fpu_decrypt(struct skcipher_request *req) { struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); struct crypto_fpu_ctx *ctx = crypto_skcipher_ctx(tfm); - struct crypto_skcipher *child = ctx->child; - SKCIPHER_REQUEST_ON_STACK(subreq, child); + struct crypto_sync_skcipher *child = ctx->child; + SYNC_SKCIPHER_REQUEST_ON_STACK(subreq, child); int err; - skcipher_request_set_tfm(subreq, child); + skcipher_request_set_sync_tfm(subreq, child); skcipher_request_set_callback(subreq, 0, NULL, NULL); skcipher_request_set_crypt(subreq, req->src, req->dst, req->cryptlen, req->iv);
@@ -93,7 +95,7 @@ static int crypto_fpu_init_tfm(struct crypto_skcipher *tfm) if (IS_ERR(cipher)) return PTR_ERR(cipher); - ctx->child = cipher; + ctx->child = (struct crypto_sync_skcipher *)cipher; return 0; }
@@ -102,7 +104,7 @@ static void crypto_fpu_exit_tfm(struct crypto_skcipher *tfm) { struct crypto_fpu_ctx *ctx = crypto_skcipher_ctx(tfm); - crypto_free_skcipher(ctx->child); + crypto_free_sync_skcipher(ctx->child); } static void crypto_fpu_free(struct skcipher_instance *inst)
--
2.17.1