diff --git a/crypto/cts.c b/crypto/cts.c index 042223f8e73364529be44a850d0dce174352c858..133f0874c95eccc7e02c26f834afed08a504a0a9 100644 --- a/crypto/cts.c +++ b/crypto/cts.c @@ -202,7 +202,8 @@ static int cts_cbc_decrypt(struct crypto_cts_ctx *ctx, /* 5. Append the tail (BB - Ln) bytes of Xn (tmp) to Cn to create En */ memcpy(s + bsize + lastn, tmp + lastn, bsize - lastn); /* 6. Decrypt En to create Pn-1 */ - memset(iv, 0, sizeof(iv)); + memzero_explicit(iv, sizeof(iv)); + sg_set_buf(&sgsrc[0], s + bsize, bsize); sg_set_buf(&sgdst[0], d, bsize); err = crypto_blkcipher_decrypt_iv(&lcldesc, sgdst, sgsrc, bsize); diff --git a/crypto/sha1_generic.c b/crypto/sha1_generic.c index 42794803c480531a60cc465657741a42ea5485dc..7bb04743278216e99a011adafa8ce8d3d97c7b4d 100644 --- a/crypto/sha1_generic.c +++ b/crypto/sha1_generic.c @@ -64,7 +64,7 @@ int crypto_sha1_update(struct shash_desc *desc, const u8 *data, src = data + done; } while (done + SHA1_BLOCK_SIZE <= len); - memset(temp, 0, sizeof(temp)); + memzero_explicit(temp, sizeof(temp)); partial = 0; } memcpy(sctx->buffer + partial, src, len - done); diff --git a/crypto/sha256_generic.c b/crypto/sha256_generic.c index 0bb5583446993aae173c0b7c015b0db9214f723f..65e7b76b057fcddc8f88a04d54b678df245a8c85 100644 --- a/crypto/sha256_generic.c +++ b/crypto/sha256_generic.c @@ -211,10 +211,9 @@ static void sha256_transform(u32 *state, const u8 *input) /* clear any sensitive info... */ a = b = c = d = e = f = g = h = t1 = t2 = 0; - memset(W, 0, 64 * sizeof(u32)); + memzero_explicit(W, 64 * sizeof(u32)); } - static int sha224_init(struct shash_desc *desc) { struct sha256_state *sctx = shash_desc_ctx(desc); @@ -317,7 +316,7 @@ static int sha224_final(struct shash_desc *desc, u8 *hash) sha256_final(desc, D); memcpy(hash, D, SHA224_DIGEST_SIZE); - memset(D, 0, SHA256_DIGEST_SIZE); + memzero_explicit(D, SHA256_DIGEST_SIZE); return 0; } diff --git a/crypto/sha512_generic.c b/crypto/sha512_generic.c index 6dde57dc511bab6c0068837356c7992f47b298cf..95db67197cd99dd1fd0cd538311f6e3f2202e7f3 100644 --- a/crypto/sha512_generic.c +++ b/crypto/sha512_generic.c @@ -239,7 +239,7 @@ static int sha384_final(struct shash_desc *desc, u8 *hash) sha512_final(desc, D); memcpy(hash, D, 48); - memset(D, 0, 64); + memzero_explicit(D, 64); return 0; } diff --git a/crypto/tgr192.c b/crypto/tgr192.c index 87403556fd0bfa5c3a4ecd40a5a707b6892fbc04..3c7af0d1ff7a6f396538a41a89e0dd5a9405e99e 100644 --- a/crypto/tgr192.c +++ b/crypto/tgr192.c @@ -612,7 +612,7 @@ static int tgr160_final(struct shash_desc *desc, u8 * out) tgr192_final(desc, D); memcpy(out, D, TGR160_DIGEST_SIZE); - memset(D, 0, TGR192_DIGEST_SIZE); + memzero_explicit(D, TGR192_DIGEST_SIZE); return 0; } @@ -623,7 +623,7 @@ static int tgr128_final(struct shash_desc *desc, u8 * out) tgr192_final(desc, D); memcpy(out, D, TGR128_DIGEST_SIZE); - memset(D, 0, TGR192_DIGEST_SIZE); + memzero_explicit(D, TGR192_DIGEST_SIZE); return 0; } diff --git a/crypto/vmac.c b/crypto/vmac.c index 2eb11a30c29cee93203a1b90a990cc4463368440..d84c24bd7ff7bb3752484a175aee7a7aadd28b21 100644 --- a/crypto/vmac.c +++ b/crypto/vmac.c @@ -613,7 +613,7 @@ static int vmac_final(struct shash_desc *pdesc, u8 *out) } mac = vmac(ctx->partial, ctx->partial_size, nonce, NULL, ctx); memcpy(out, &mac, sizeof(vmac_t)); - memset(&mac, 0, sizeof(vmac_t)); + memzero_explicit(&mac, sizeof(vmac_t)); memset(&ctx->__vmac_ctx, 0, sizeof(struct vmac_ctx)); ctx->partial_size = 0; return 0; diff --git a/crypto/wp512.c b/crypto/wp512.c index 180f1d6e03f48fc20ef787061d8866e6af429c68..ec64e7762fbb55a579fefd781757a9d29182f5da 100644 --- a/crypto/wp512.c +++ b/crypto/wp512.c @@ -1102,8 +1102,8 @@ static int wp384_final(struct shash_desc *desc, u8 *out) u8 D[64]; wp512_final(desc, D); - memcpy (out, D, WP384_DIGEST_SIZE); - memset (D, 0, WP512_DIGEST_SIZE); + memcpy(out, D, WP384_DIGEST_SIZE); + memzero_explicit(D, WP512_DIGEST_SIZE); return 0; } @@ -1113,8 +1113,8 @@ static int wp256_final(struct shash_desc *desc, u8 *out) u8 D[64]; wp512_final(desc, D); - memcpy (out, D, WP256_DIGEST_SIZE); - memset (D, 0, WP512_DIGEST_SIZE); + memcpy(out, D, WP256_DIGEST_SIZE); + memzero_explicit(D, WP512_DIGEST_SIZE); return 0; } diff --git a/drivers/char/random.c b/drivers/char/random.c index 82759cef904332cbe6800d4be9c4e08aa420f19c..04645c09fe5e5eee7f6699c451e9e4f6f8368958 100644 --- a/drivers/char/random.c +++ b/drivers/char/random.c @@ -1106,7 +1106,7 @@ static void extract_buf(struct entropy_store *r, __u8 *out) __mix_pool_bytes(r, hash.w, sizeof(hash.w)); spin_unlock_irqrestore(&r->lock, flags); - memset(workspace, 0, sizeof(workspace)); + memzero_explicit(workspace, sizeof(workspace)); /* * In case the hash function has some recognizable output @@ -1118,7 +1118,7 @@ static void extract_buf(struct entropy_store *r, __u8 *out) hash.w[2] ^= rol32(hash.w[2], 16); memcpy(out, &hash, EXTRACT_SIZE); - memset(&hash, 0, sizeof(hash)); + memzero_explicit(&hash, sizeof(hash)); } /* @@ -1175,7 +1175,7 @@ static ssize_t extract_entropy(struct entropy_store *r, void *buf, } /* Wipe data just returned from memory */ - memset(tmp, 0, sizeof(tmp)); + memzero_explicit(tmp, sizeof(tmp)); return ret; } @@ -1218,7 +1218,7 @@ static ssize_t extract_entropy_user(struct entropy_store *r, void __user *buf, } /* Wipe data just returned from memory */ - memset(tmp, 0, sizeof(tmp)); + memzero_explicit(tmp, sizeof(tmp)); return ret; } diff --git a/include/linux/string.h b/include/linux/string.h index e6edfe51575a6f5a452e937376add0afdb7c5d48..2e22a2e58f3af56018c0e68cda2603211ecc3aca 100644 --- a/include/linux/string.h +++ b/include/linux/string.h @@ -132,7 +132,7 @@ int bprintf(u32 *bin_buf, size_t size, const char *fmt, ...) __printf(3, 4); #endif extern ssize_t memory_read_from_buffer(void *to, size_t count, loff_t *ppos, - const void *from, size_t available); + const void *from, size_t available); /** * strstarts - does @str start with @prefix? @@ -144,7 +144,8 @@ static inline bool strstarts(const char *str, const char *prefix) return strncmp(str, prefix, strlen(prefix)) == 0; } -extern size_t memweight(const void *ptr, size_t bytes); +size_t memweight(const void *ptr, size_t bytes); +void memzero_explicit(void *s, size_t count); /** * kbasename - return the last part of a pathname. diff --git a/lib/string.c b/lib/string.c index 2fc20aa06f848fcebd8aa30d238942f5ec399690..10063300b83009dfcdc08988d640fc191481dde5 100644 --- a/lib/string.c +++ b/lib/string.c @@ -598,6 +598,22 @@ void *memset(void *s, int c, size_t count) EXPORT_SYMBOL(memset); #endif +/** + * memzero_explicit - Fill a region of memory (e.g. sensitive + * keying data) with 0s. + * @s: Pointer to the start of the area. + * @count: The size of the area. + * + * memzero_explicit() doesn't need an arch-specific version as + * it just invokes the one of memset() implicitly. + */ +void memzero_explicit(void *s, size_t count) +{ + memset(s, 0, count); + OPTIMIZER_HIDE_VAR(s); +} +EXPORT_SYMBOL(memzero_explicit); + #ifndef __HAVE_ARCH_MEMCPY /** * memcpy - Copy one area of memory to another