github-mirror/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux.git synced 2026-11-09 13:44:03 +01:00
Code Issues Actions Packages Projects Releases Wiki Activity Graph

dm-crypt: Use memzero_explicit() to wipe key material

Browse Source 
The code still wipes key material with memset(). Use memzero_explicit()
to prevent the compiler from optimizing these wipes away.

Also use size_t for the string length passed to memzero_explicit() and
drop the redundant sizeof(u8) multiplications.

Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
This commit is contained in:
Thorsten Blum 2026-08-15 13:05:33 +02:00 committed by Mikulas Patocka
parent e3683a76a3
commit 624c30d967
1 changed files with 9 additions and 9 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

18
drivers/md/dm-crypt.c
View File

@ -513,7 +513,7 @@ static void crypt_iv_lmk_wipe(struct crypt_config *cc)
struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk;
if (lmk->seed)
memset(lmk->seed, 0, LMK_SEED_SIZE);
memzero_explicit(lmk->seed, LMK_SEED_SIZE);
}
static void crypt_iv_lmk_one(struct crypt_config *cc, u8 *iv,
@ -630,8 +630,8 @@ static void crypt_iv_tcw_wipe(struct crypt_config *cc)
{
struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw;
memset(tcw->iv_seed, 0, cc->iv_size);
memset(tcw->whitening, 0, TCW_WHITENING_SIZE);
memzero_explicit(tcw->iv_seed, cc->iv_size);
memzero_explicit(tcw->whitening, TCW_WHITENING_SIZE);
}
static void crypt_iv_tcw_whitening(struct crypt_config *cc,
@ -2595,7 +2595,7 @@ static int get_key_size(char **key_string)
static int crypt_set_key(struct crypt_config *cc, char *key)
{
int r = -EINVAL;
int key_string_len = strlen(key);
size_t key_string_len = strlen(key);
/* Hyphen (which gives a key_size of zero) means there is no key. */
if (!cc->key_size && strcmp(key, "-"))
@ -2624,7 +2624,7 @@ static int crypt_set_key(struct crypt_config *cc, char *key)
out:
/* Hex key string not needed after here, so wipe it. */
memset(key, '0', key_string_len);
memzero_explicit(key, key_string_len);
return r;
}
@ -2643,7 +2643,7 @@ static int crypt_wipe_key(struct crypt_config *cc)
kfree_sensitive(cc->key_string);
cc->key_string = NULL;
r = crypt_setkey(cc);
memset(&cc->key, 0, cc->key_size * sizeof(u8));
memzero_explicit(cc->key, cc->key_size);
return r;
}
@ -3064,7 +3064,7 @@ static int crypt_ctr_cipher(struct dm_target *ti, char *cipher_in, char *key)
/* wipe the kernel key payload copy */
if (cc->key_string)
memset(cc->key, 0, cc->key_size * sizeof(u8));
memzero_explicit(cc->key, cc->key_size);
return ret;
}
@ -3643,7 +3643,7 @@ static int crypt_message(struct dm_target *ti, unsigned int argc, char **argv,
/* The key size may not be changed. */
key_size = get_key_size(&argv[2]);
if (key_size < 0 || cc->key_size != key_size) {
memset(argv[2], '0', strlen(argv[2]));
memzero_explicit(argv[2], strlen(argv[2]));
return -EINVAL;
}
@ -3654,7 +3654,7 @@ static int crypt_message(struct dm_target *ti, unsigned int argc, char **argv,
ret = cc->iv_gen_ops->init(cc);
/* wipe the kernel key payload copy */
if (cc->key_string)
memset(cc->key, 0, cc->key_size * sizeof(u8));
memzero_explicit(cc->key, cc->key_size);
return ret;
}
if (argc == 2 && !strcasecmp(argv[1], "wipe"))