FAQ Search Today's Posts Mark Forums Read
» Video Reviews

» Linux Archive

Linux-archive is a website aiming to archive linux email lists and to make them easily accessible for linux users/developers.


» Sponsor

» Partners

» Sponsor

Go Back   Linux Archive > Redhat > Device-mapper Development

 
 
LinkBack Thread Tools
 
Old 10-10-2010, 06:56 PM
Milan Broz
 
Default Fix double free and use generic private pointer in per-cpu struct

On 10/10/2010 07:07 PM, Mike Snitzer wrote:

> I'll send patch on top of Andi's v3 if it helps something. (When back to my devel machine).
> That'll be helpful (I'm sure Andi is interested).
ok here are my changes on top of v3 - one bugfix and generic IV pointer.
If you merge it to v4 and it appears in git as one patch I have no problem with that.

Thanks,
Milan


[PATCH] Use generic private pointer in per-cpu struct

If an IV need to use per-cpu struct, it should allocate
it in its constructor and free in destructor.
(There will be possible more compatibility IVs which need per-cpu struct.)

For ESSIV, only tfm pointer is needed so use iv_private directly.

Also fix double free of salt in ESSIV IV constructor.

Signed-off-by: Milan Broz <mbroz@redhat.com>

diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c
index 8802e1d..88a2a05 100644
--- a/drivers/md/dm-crypt.c
+++ b/drivers/md/dm-crypt.c
@@ -82,11 +82,6 @@ struct iv_essiv_private {
u8 *salt;
};

-/* Duplicated per CPU state for cipher */
-struct iv_essiv_private_cpu {
- struct crypto_cipher *tfm;
-};
-
struct iv_benbi_private {
int shift;
};
@@ -101,7 +96,9 @@ enum flags { DM_CRYPT_SUSPENDED, DM_CRYPT_KEY_VALID };
struct crypt_cpu {
struct ablkcipher_request *req;
struct crypto_ablkcipher *tfm;
- struct iv_essiv_private_cpu ie;
+
+ /* ESSIV: struct crypto_cipher *essiv_tfm */
+ void *iv_private;
};

/*
@@ -234,6 +231,8 @@ static int crypt_iv_essiv_init(struct crypt_config *cc)
struct iv_essiv_private *essiv = &cc->iv_gen_private.essiv;
struct hash_desc desc;
struct scatterlist sg;
+ struct crypt_cpu *cs;
+ struct crypto_cipher *essiv_tfm;
int err, n, cpu;

sg_init_one(&sg, cc->key, cc->key_size);
@@ -245,9 +244,10 @@ static int crypt_iv_essiv_init(struct crypt_config *cc)
return err;

for_each_possible_cpu (cpu) {
- struct crypt_cpu *cs = per_cpu_ptr(cc->cpu, cpu);
+ cs = per_cpu_ptr(cc->cpu, cpu);
+ essiv_tfm = cs->iv_private,

- n = crypto_cipher_setkey(cs->ie.tfm, essiv->salt,
+ n = crypto_cipher_setkey(essiv_tfm, essiv->salt,
crypto_hash_digestsize(essiv->hash_tfm));
if (n) {
err = n;
@@ -263,14 +263,17 @@ static int crypt_iv_essiv_wipe(struct crypt_config *cc)
{
struct iv_essiv_private *essiv = &cc->iv_gen_private.essiv;
unsigned salt_size = crypto_hash_digestsize(essiv->hash_tfm);
+ struct crypt_cpu *cs;
+ struct crypto_cipher *essiv_tfm;
int cpu, err, n;

memset(essiv->salt, 0, salt_size);

err = 0;
for_each_possible_cpu (cpu) {
- struct crypt_cpu *cs = per_cpu_ptr(cc->cpu, cpu);
- n = crypto_cipher_setkey(cs->ie.tfm, essiv->salt, salt_size);
+ cs = per_cpu_ptr(cc->cpu, cpu);
+ essiv_tfm = cs->iv_private;
+ n = crypto_cipher_setkey(essiv_tfm, essiv->salt, salt_size);
if (n)
err = n;
}
@@ -312,6 +315,8 @@ static struct crypto_cipher *setup_essiv_cpu(struct crypt_config *cc,
static void crypt_iv_essiv_dtr(struct crypt_config *cc)
{
int cpu;
+ struct crypt_cpu *cs;
+ struct crypto_cipher *essiv_tfm;
struct iv_essiv_private *essiv = &cc->iv_gen_private.essiv;

crypto_free_hash(essiv->hash_tfm);
@@ -321,11 +326,11 @@ static void crypt_iv_essiv_dtr(struct crypt_config *cc)
essiv->salt = NULL;

for_each_possible_cpu (cpu) {
- struct crypt_cpu *cs = per_cpu_ptr(cc->cpu, cpu);
- if (cs->ie.tfm) {
- crypto_free_cipher(cs->ie.tfm);
- cs->ie.tfm = NULL;
- }
+ cs = per_cpu_ptr(cc->cpu, cpu);
+ essiv_tfm = cs->iv_private;
+ if (essiv_tfm)
+ crypto_free_cipher(essiv_tfm);
+ cs->iv_private = NULL;
}
}

@@ -365,11 +370,10 @@ static int crypt_iv_essiv_ctr(struct crypt_config *cc, struct dm_target *ti,
essiv_tfm = setup_essiv_cpu(cc, ti, salt,
crypto_hash_digestsize(hash_tfm));
if (IS_ERR(essiv_tfm)) {
- kfree(salt);
crypt_iv_essiv_dtr(cc);
return PTR_ERR(essiv_tfm);
}
- per_cpu_ptr(cc->cpu, cpu)->ie.tfm = essiv_tfm;
+ per_cpu_ptr(cc->cpu, cpu)->iv_private = essiv_tfm;
}
return 0;

@@ -382,9 +386,11 @@ bad:

static int crypt_iv_essiv_gen(struct crypt_config *cc, u8 *iv, sector_t sector)
{
+ struct crypto_cipher *essiv_tfm = crypt_me(cc)->iv_private;
+
memset(iv, 0, cc->iv_size);
*(u64 *)iv = cpu_to_le64(sector);
- crypto_cipher_encrypt_one(crypt_me(cc)->ie.tfm, iv, iv);
+ crypto_cipher_encrypt_one(essiv_tfm, iv, iv);
return 0;
}



--
dm-devel mailing list
dm-devel@redhat.com
https://www.redhat.com/mailman/listinfo/dm-devel
 
Old 10-14-2010, 07:26 PM
Milan Broz
 
Default Fix double free and use generic private pointer in per-cpu struct

On 10/10/2010 08:56 PM, Milan Broz wrote:
> On 10/10/2010 07:07 PM, Mike Snitzer wrote:
>
>> I'll send patch on top of Andi's v3 if it helps something. (When back to my devel machine).
>> That'll be helpful (I'm sure Andi is interested).
> ok here are my changes on top of v3 - one bugfix and generic IV pointer.
> If you merge it to v4 and it appears in git as one patch I have no problem with that.
>
> Thanks,
> Milan
>
>
> [PATCH] Use generic private pointer in per-cpu struct

Hi Andi,

any progress here?
I would like to achieve some consensus and merge some version
of patch to dm tree...
Maybe with known problems if there is no better solution for now.

Thanks,
Milan

--
dm-devel mailing list
dm-devel@redhat.com
https://www.redhat.com/mailman/listinfo/dm-devel
 

Thread Tools




All times are GMT. The time now is 06:57 AM.

VBulletin, Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Content Relevant URLs by vBSEO ©2007, Crawlability, Inc.
Copyright 2007 - 2008, www.linux-archive.org