kernel/linux.git/net/tipc/crypto.c, branch linux-5.9.y

tipc: fix using smp_processor_id() in preemptible

2020-08-31T02:12:17+00:00

The 'this_cpu_ptr()' is used to obtain the AEAD key' TFM on the current CPU for encryption, however the execution can be preemptible since it's actually user-space context, so the 'using smp_processor_id() in preemptible' has been observed. We fix the issue by using the 'get/put_cpu_ptr()' API which consists of a 'preempt_disable()' instead. Fixes: fc1b6d6de220 ("tipc: introduce TIPC encryption & authentication") Acked-by: Jon Maloy Signed-off-by: Tuong Lien Signed-off-by: David S. Miller

tipc: call rcu_read_lock() in tipc_aead_encrypt_done()

2020-08-20T23:42:08+00:00

b->media->send_msg() requires rcu_read_lock(), as we can see elsewhere in tipc, tipc_bearer_xmit, tipc_bearer_xmit_skb and tipc_bearer_bc_xmit(). Syzbot has reported this issue as: net/tipc/bearer.c:466 suspicious rcu_dereference_check() usage! Workqueue: cryptd cryptd_queue_worker Call Trace: tipc_l2_send_msg+0x354/0x420 net/tipc/bearer.c:466 tipc_aead_encrypt_done+0x204/0x3a0 net/tipc/crypto.c:761 cryptd_aead_crypt+0xe8/0x1d0 crypto/cryptd.c:739 cryptd_queue_worker+0x118/0x1b0 crypto/cryptd.c:181 process_one_work+0x94c/0x1670 kernel/workqueue.c:2269 worker_thread+0x64c/0x1120 kernel/workqueue.c:2415 kthread+0x3b5/0x4a0 kernel/kthread.c:291 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:293 So fix it by calling rcu_read_lock() in tipc_aead_encrypt_done() for b->media->send_msg(). Fixes: fc1b6d6de220 ("tipc: introduce TIPC encryption & authentication") Reported-by: syzbot+47bbc6b678d317cccbe0@syzkaller.appspotmail.com Signed-off-by: Xin Long Signed-off-by: David S. Miller

mm, treewide: rename kzfree() to kfree_sensitive()

2020-08-07T18:33:22+00:00

As said by Linus: A symmetric naming is only helpful if it implies symmetries in use. Otherwise it's actively misleading. In "kzalloc()", the z is meaningful and an important part of what the caller wants. In "kzfree()", the z is actively detrimental, because maybe in the future we really _might_ want to use that "memfill(0xdeadbeef)" or something. The "zero" part of the interface isn't even _relevant_. The main reason that kzfree() exists is to clear sensitive information that should not be leaked to other future users of the same memory objects. Rename kzfree() to kfree_sensitive() to follow the example of the recently added kvfree_sensitive() and make the intention of the API more explicit. In addition, memzero_explicit() is used to clear the memory to make sure that it won't get optimized away by the compiler. The renaming is done by using the command sequence: git grep -w --name-only kzfree |\ xargs sed -i 's/kzfree/kfree_sensitive/' followed by some editing of the kfree_sensitive() kerneldoc and adding a kzfree backward compatibility macro in slab.h. [akpm@linux-foundation.org: fs/crypto/inline_crypt.c needs linux/slab.h] [akpm@linux-foundation.org: fix fs/crypto/inline_crypt.c some more] Suggested-by: Joe Perches Signed-off-by: Waiman Long Signed-off-by: Andrew Morton Acked-by: David Howells Acked-by: Michal Hocko Acked-by: Johannes Weiner Cc: Jarkko Sakkinen Cc: James Morris Cc: "Serge E. Hallyn" Cc: Joe Perches Cc: Matthew Wilcox Cc: David Rientjes Cc: Dan Carpenter Cc: "Jason A . Donenfeld" Link: http://lkml.kernel.org/r/20200616154311.12314-3-longman@redhat.com Signed-off-by: Linus Torvalds

Revert "tipc: Fix potential tipc_aead refcnt leak in tipc_crypto_rcv"

2020-06-02T22:13:47+00:00

This reverts commit 441870ee4240cf67b5d3ab8e16216a9ff42eb5d6. Like the previous patch in this series, we revert the above commit that causes similar issues with the 'aead' object. Acked-by: Jon Maloy Signed-off-by: Tuong Lien Signed-off-by: David S. Miller

tipc: Fix potential tipc_aead refcnt leak in tipc_crypto_rcv

2020-04-18T20:17:04+00:00

tipc_crypto_rcv() invokes tipc_aead_get(), which returns a reference of the tipc_aead object to "aead" with increased refcnt. When tipc_crypto_rcv() returns, the original local reference of "aead" becomes invalid, so the refcount should be decreased to keep refcount balanced. The issue happens in one error path of tipc_crypto_rcv(). When TIPC message decryption status is EINPROGRESS or EBUSY, the function forgets to decrease the refcnt increased by tipc_aead_get() and causes a refcnt leak. Fix this issue by calling tipc_aead_put() on the error path when TIPC message decryption status is EINPROGRESS or EBUSY. Signed-off-by: Xiyu Yang Signed-off-by: Xin Tan Signed-off-by: David S. Miller

net/tipc: Replace rcu_swap_protected() with rcu_replace_pointer()

2019-12-12T18:19:40+00:00

This commit replaces the use of rcu_swap_protected() with the more intuitively appealing rcu_replace_pointer() as a step towards removing rcu_swap_protected(). Link: https://lore.kernel.org/lkml/CAHk-=wiAsJLw1egFEE=Z7-GGtM6wcvtyytXZA1+BHqta4gg6Hw@mail.gmail.com/ Reported-by: Linus Torvalds Reported-by: kbuild test robot Signed-off-by: Paul E. McKenney [ paulmck: Updated based on Ying Xue and Tuong Lien Tong feedback. ] Cc: Jon Maloy Cc: Ying Xue Cc: "David S. Miller" Cc: Cc:

tipc: fix update of the uninitialized variable err

2019-11-12T06:04:03+00:00

Variable err is not uninitialized and hence can potentially contain any garbage value. This may cause an error when logical or'ing the return values from the calls to functions crypto_aead_setauthsize or crypto_aead_setkey. Fix this by setting err to the return of crypto_aead_setauthsize rather than or'ing in the return into the uninitialized variable Addresses-Coverity: ("Uninitialized scalar variable") Fixes: fc1b6d6de220 ("tipc: introduce TIPC encryption & authentication") Signed-off-by: Colin Ian King Signed-off-by: David S. Miller

tipc: introduce TIPC encryption & authentication

2019-11-08T22:01:59+00:00

This commit offers an option to encrypt and authenticate all messaging, including the neighbor discovery messages. The currently most advanced algorithm supported is the AEAD AES-GCM (like IPSec or TLS). All encryption/decryption is done at the bearer layer, just before leaving or after entering TIPC. Supported features: - Encryption & authentication of all TIPC messages (header + data); - Two symmetric-key modes: Cluster and Per-node; - Automatic key switching; - Key-expired revoking (sequence number wrapped); - Lock-free encryption/decryption (RCU); - Asynchronous crypto, Intel AES-NI supported; - Multiple cipher transforms; - Logs & statistics; Two key modes: - Cluster key mode: One single key is used for both TX & RX in all nodes in the cluster. - Per-node key mode: Each nodes in the cluster has one specific TX key. For RX, a node requires its peers' TX key to be able to decrypt the messages from those peers. Key setting from user-space is performed via netlink by a user program (e.g. the iproute2 'tipc' tool). Internal key state machine: Attach Align(RX) +-+ +-+ | V | V +---------+ Attach +---------+ | IDLE |---------------->| PENDING |(user = 0) +---------+ +---------+ A A Switch| A | | | | | | Free(switch/revoked) | | (Free)| +----------------------+ | |Timeout | (TX) | | |(RX) | | | | | | v | +---------+ Switch +---------+ | PASSIVE |<----------------| ACTIVE | +---------+ (RX) +---------+ (user = 1) (user >= 1) The number of TFMs is 10 by default and can be changed via the procfs 'net/tipc/max_tfms'. At this moment, as for simplicity, this file is also used to print the crypto statistics at runtime: echo 0xfff1 > /proc/sys/net/tipc/max_tfms The patch defines a new TIPC version (v7) for the encryption message (- backward compatibility as well). The message is basically encapsulated as follows: +----------------------------------------------------------+ | TIPCv7 encryption | Original TIPCv2 | Authentication | | header | packet (encrypted) | Tag | +----------------------------------------------------------+ The throughput is about ~40% for small messages (compared with non- encryption) and ~9% for large messages. With the support from hardware crypto i.e. the Intel AES-NI CPU instructions, the throughput increases upto ~85% for small messages and ~55% for large messages. By default, the new feature is inactive (i.e. no encryption) until user sets a key for TIPC. There is however also a new option - "TIPC_CRYPTO" in the kernel configuration to enable/disable the new code when needed. MAINTAINERS | add two new files 'crypto.h' & 'crypto.c' in tipc Acked-by: Ying Xue Acked-by: Jon Maloy Signed-off-by: Tuong Lien Signed-off-by: David S. Miller