kmemdup can return a null pointer so need to check for it, otherwise
the null key will be dereferenced later in tipc_crypto_key_xmit as
can be seen in the trace [1].
Cc: Jon Maloy <[email protected]>
Cc: Ying Xue <[email protected]>
Cc: "David S. Miller" <[email protected]>
Cc: Jakub Kicinski <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected] # 5.15, 5.14, 5.10
[1] https://syzkaller.appspot.com/bug?id=bca180abb29567b189efdbdb34cbf7ba851c2a58
Reported-by: Dmitry Vyukov <[email protected]>
Signed-off-by: Tadeusz Struk <[email protected]>
---
net/tipc/crypto.c | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/net/tipc/crypto.c b/net/tipc/crypto.c
index dc60c32bb70d..988a343f9fd5 100644
--- a/net/tipc/crypto.c
+++ b/net/tipc/crypto.c
@@ -597,6 +597,11 @@ static int tipc_aead_init(struct tipc_aead **aead, struct tipc_aead_key *ukey,
tmp->cloned = NULL;
tmp->authsize = TIPC_AES_GCM_TAG_SIZE;
tmp->key = kmemdup(ukey, tipc_aead_key_size(ukey), GFP_KERNEL);
+ if (!tmp->key) {
+ free_percpu(tmp->tfm_entry);
+ kfree_sensitive(tmp);
+ return -ENOMEM;
+ }
memcpy(&tmp->salt, ukey->key + keylen, TIPC_AES_GCM_SALT_SIZE);
atomic_set(&tmp->users, 0);
atomic64_set(&tmp->seqno, 0);
--
2.33.1
Some functions, like tipc_crypto_start use inconsisten GFP flags
when allocating memory. The mentioned function use GFP_ATOMIC to
to alloc a crypto instance, and then calls alloc_ordered_workqueue()
which allocates memory with GFP_KERNEL. tipc_aead_init() function
even uses GFP_KERNEL and GFP_ATOMIC interchangeably.
No doc comment specifies what context a function is designed to
work in, but the flags should at least be consistent within a function.
Cc: Jon Maloy <[email protected]>
Cc: Ying Xue <[email protected]>
Cc: "David S. Miller" <[email protected]>
Cc: Jakub Kicinski <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Signed-off-by: Tadeusz Struk <[email protected]>
---
net/tipc/crypto.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/net/tipc/crypto.c b/net/tipc/crypto.c
index 988a343f9fd5..a59c4eece5db 100644
--- a/net/tipc/crypto.c
+++ b/net/tipc/crypto.c
@@ -524,7 +524,7 @@ static int tipc_aead_init(struct tipc_aead **aead, struct tipc_aead_key *ukey,
return -EEXIST;
/* Allocate a new AEAD */
- tmp = kzalloc(sizeof(*tmp), GFP_ATOMIC);
+ tmp = kzalloc(sizeof(*tmp), GFP_KERNEL);
if (unlikely(!tmp))
return -ENOMEM;
@@ -1475,7 +1475,7 @@ int tipc_crypto_start(struct tipc_crypto **crypto, struct net *net,
return -EEXIST;
/* Allocate crypto */
- c = kzalloc(sizeof(*c), GFP_ATOMIC);
+ c = kzalloc(sizeof(*c), GFP_KERNEL);
if (!c)
return -ENOMEM;
@@ -1489,7 +1489,7 @@ int tipc_crypto_start(struct tipc_crypto **crypto, struct net *net,
}
/* Allocate statistic structure */
- c->stats = alloc_percpu_gfp(struct tipc_crypto_stats, GFP_ATOMIC);
+ c->stats = alloc_percpu(struct tipc_crypto_stats);
if (!c->stats) {
if (c->wq)
destroy_workqueue(c->wq);
@@ -2462,7 +2462,7 @@ static void tipc_crypto_work_tx(struct work_struct *work)
}
/* Lets duplicate it first */
- skey = kmemdup(aead->key, tipc_aead_key_size(aead->key), GFP_ATOMIC);
+ skey = kmemdup(aead->key, tipc_aead_key_size(aead->key), GFP_KERNEL);
rcu_read_unlock();
/* Now, generate new key, initiate & distribute it */
--
2.33.1
On 11/11/21 15:59, Tadeusz Struk wrote:
> kmemdup can return a null pointer so need to check for it, otherwise
> the null key will be dereferenced later in tipc_crypto_key_xmit as
> can be seen in the trace [1].
>
> Cc: Jon Maloy <[email protected]>
> Cc: Ying Xue <[email protected]>
> Cc: "David S. Miller" <[email protected]>
> Cc: Jakub Kicinski <[email protected]>
> Cc: [email protected]
> Cc: [email protected]
> Cc: [email protected]
> Cc: [email protected] # 5.15, 5.14, 5.10
>
> [1] https://syzkaller.appspot.com/bug?id=bca180abb29567b189efdbdb34cbf7ba851c2a58
>
> Reported-by: Dmitry Vyukov <[email protected]>
> Signed-off-by: Tadeusz Struk <[email protected]>
> ---
> net/tipc/crypto.c | 5 +++++
> 1 file changed, 5 insertions(+)
>
> diff --git a/net/tipc/crypto.c b/net/tipc/crypto.c
> index dc60c32bb70d..988a343f9fd5 100644
> --- a/net/tipc/crypto.c
> +++ b/net/tipc/crypto.c
> @@ -597,6 +597,11 @@ static int tipc_aead_init(struct tipc_aead **aead, struct tipc_aead_key *ukey,
> tmp->cloned = NULL;
> tmp->authsize = TIPC_AES_GCM_TAG_SIZE;
> tmp->key = kmemdup(ukey, tipc_aead_key_size(ukey), GFP_KERNEL);
> + if (!tmp->key) {
> + free_percpu(tmp->tfm_entry);
> + kfree_sensitive(tmp);
> + return -ENOMEM;
> + }
> memcpy(&tmp->salt, ukey->key + keylen, TIPC_AES_GCM_SALT_SIZE);
> atomic_set(&tmp->users, 0);
> atomic64_set(&tmp->seqno, 0);
Acked-by: Jon Maloy <[email protected]>
On Thu, 11 Nov 2021 12:59:15 -0800 Tadeusz Struk wrote:
> kmemdup can return a null pointer so need to check for it, otherwise
> the null key will be dereferenced later in tipc_crypto_key_xmit as
> can be seen in the trace [1].
> Reported-by: Dmitry Vyukov <[email protected]>
> Signed-off-by: Tadeusz Struk <[email protected]>
Fixes: 1ef6f7c9390f ("tipc: add automatic session key exchange")
On Thu, 11 Nov 2021 19:06:18 -0500 Jon Maloy wrote:
> On 11/11/21 15:59, Tadeusz Struk wrote:
> > kmemdup can return a null pointer so need to check for it, otherwise
> > the null key will be dereferenced later in tipc_crypto_key_xmit as
> > can be seen in the trace [1].
> > [1] https://syzkaller.appspot.com/bug?id=bca180abb29567b189efdbdb34cbf7ba851c2a58
> >
> > Reported-by: Dmitry Vyukov <[email protected]>
> > Signed-off-by: Tadeusz Struk <[email protected]>
> > ---
> > net/tipc/crypto.c | 5 +++++
> > 1 file changed, 5 insertions(+)
> >
> > diff --git a/net/tipc/crypto.c b/net/tipc/crypto.c
> > index dc60c32bb70d..988a343f9fd5 100644
> > --- a/net/tipc/crypto.c
> > +++ b/net/tipc/crypto.c
> > @@ -597,6 +597,11 @@ static int tipc_aead_init(struct tipc_aead **aead, struct tipc_aead_key *ukey,
> > tmp->cloned = NULL;
> > tmp->authsize = TIPC_AES_GCM_TAG_SIZE;
> > tmp->key = kmemdup(ukey, tipc_aead_key_size(ukey), GFP_KERNEL);
> > + if (!tmp->key) {
> > + free_percpu(tmp->tfm_entry);
> > + kfree_sensitive(tmp);
> > + return -ENOMEM;
> > + }
> Acked-by: Jon Maloy <[email protected]>
Hm, shouldn't we free all the tfm entries here?
On 11/12/21 20:13, Jakub Kicinski wrote:
>>> @@ -597,6 +597,11 @@ static int tipc_aead_init(struct tipc_aead **aead, struct tipc_aead_key *ukey,
>>> tmp->cloned = NULL;
>>> tmp->authsize = TIPC_AES_GCM_TAG_SIZE;
>>> tmp->key = kmemdup(ukey, tipc_aead_key_size(ukey), GFP_KERNEL);
>>> + if (!tmp->key) {
>>> + free_percpu(tmp->tfm_entry);
>>> + kfree_sensitive(tmp);
>>> + return -ENOMEM;
>>> + }
>> Acked-by: Jon Maloy<[email protected]>
> Hm, shouldn't we free all the tfm entries here?
Right, I think we just need to call tipc_aead_free(&tmp->rcu);
here and return an error.
--
Thanks,
Tadeusz
Hello:
This patch was applied to netdev/net.git (master)
by David S. Miller <[email protected]>:
On Thu, 11 Nov 2021 12:59:16 -0800 you wrote:
> Some functions, like tipc_crypto_start use inconsisten GFP flags
> when allocating memory. The mentioned function use GFP_ATOMIC to
> to alloc a crypto instance, and then calls alloc_ordered_workqueue()
> which allocates memory with GFP_KERNEL. tipc_aead_init() function
> even uses GFP_KERNEL and GFP_ATOMIC interchangeably.
> No doc comment specifies what context a function is designed to
> work in, but the flags should at least be consistent within a function.
>
> [...]
Here is the summary with links:
- tipc: use consistent GFP flags
https://git.kernel.org/netdev/net/c/86c3a3e964d9
You are awesome, thank you!
--
Deet-doot-dot, I am a bot.
https://korg.docs.kernel.org/patchwork/pwbot.html
On 11/15/21 05:00, [email protected] wrote:
> This patch was applied to netdev/net.git (master)
> by David S. Miller<[email protected]>:
>
> On Thu, 11 Nov 2021 12:59:16 -0800 you wrote:
>> Some functions, like tipc_crypto_start use inconsisten GFP flags
>> when allocating memory. The mentioned function use GFP_ATOMIC to
>> to alloc a crypto instance, and then calls alloc_ordered_workqueue()
>> which allocates memory with GFP_KERNEL. tipc_aead_init() function
>> even uses GFP_KERNEL and GFP_ATOMIC interchangeably.
>> No doc comment specifies what context a function is designed to
>> work in, but the flags should at least be consistent within a function.
>>
>> [...]
> Here is the summary with links:
> - tipc: use consistent GFP flags
> https://git.kernel.org/netdev/net/c/86c3a3e964d9
>
> You are awesome, thank you!
Thanks, you are awesome too! ;)
Any feedback about the patch:
[PATCH v2] tipc: check for null after calling kmemdup
--
Thanks,
Tadeusz
On Fri, 12 Nov 2021 21:42:11 -0800 Tadeusz Struk wrote:
> On 11/12/21 20:13, Jakub Kicinski wrote:
> [...]
> >> Acked-by: Jon Maloy<[email protected]>
> > Hm, shouldn't we free all the tfm entries here?
>
> Right, I think we just need to call tipc_aead_free(&tmp->rcu);
> here and return an error.
Would be good to get an ack From Jon or Ying on that one.
On Tue, 16 Nov 2021 11:32:32 -0800 Jakub Kicinski wrote:
> On Fri, 12 Nov 2021 21:42:11 -0800 Tadeusz Struk wrote:
> > On 11/12/21 20:13, Jakub Kicinski wrote:
> > [...]
> [...]
> > > Hm, shouldn't we free all the tfm entries here?
> >
> > Right, I think we just need to call tipc_aead_free(&tmp->rcu);
> > here and return an error.
>
> Would be good to get an ack From Jon or Ying on that one.
Ah, I hit reply on the wrong sub-thread, this was meant for the "any
feedback question".