linux.git/net/tipc/crypto.c, branch v6.16 Linux kernel source tree net: tipc: fix refcount warning in tipc_aead_encrypt 2025-05-29T10:07:26+00:00 Charalampos Mitrodimas charmitro@posteo.net 2025-05-27T16:35:44+00:00 f29ccaa07cf3d35990f4d25028cc55470d29372b syzbot reported a refcount warning [1] caused by calling get_net() on a network namespace that is being destroyed (refcount=0). This happens when a TIPC discovery timer fires during network namespace cleanup. The recently added get_net() call in commit e279024617134 ("net/tipc: fix slab-use-after-free Read in tipc_aead_encrypt_done") attempts to hold a reference to the network namespace. However, if the namespace is already being destroyed, its refcount might be zero, leading to the use-after-free warning. Replace get_net() with maybe_get_net(), which safely checks if the refcount is non-zero before incrementing it. If the namespace is being destroyed, return -ENODEV early, after releasing the bearer reference. [1]: https://lore.kernel.org/all/68342b55.a70a0220.253bc2.0091.GAE@google.com/T/#m12019cf9ae77e1954f666914640efa36d52704a2 Reported-by: syzbot+f0c4a4aba757549ae26c@syzkaller.appspotmail.com Closes: https://lore.kernel.org/all/68342b55.a70a0220.253bc2.0091.GAE@google.com/T/#m12019cf9ae77e1954f666914640efa36d52704a2 Fixes: e27902461713 ("net/tipc: fix slab-use-after-free Read in tipc_aead_encrypt_done") Signed-off-by: Charalampos Mitrodimas <charmitro@posteo.net> Reviewed-by: Tung Nguyen <tung.quang.nguyen@est.tech> Link: https://patch.msgid.link/20250527-net-tipc-warning-v2-1-df3dc398a047@posteo.net Signed-off-by: Paolo Abeni <pabeni@redhat.com> 
syzbot reported a refcount warning [1] caused by calling get_net() on
a network namespace that is being destroyed (refcount=0). This happens
when a TIPC discovery timer fires during network namespace cleanup.

The recently added get_net() call in commit e279024617134 ("net/tipc:
fix slab-use-after-free Read in tipc_aead_encrypt_done") attempts to
hold a reference to the network namespace. However, if the namespace
is already being destroyed, its refcount might be zero, leading to the
use-after-free warning.

Replace get_net() with maybe_get_net(), which safely checks if the
refcount is non-zero before incrementing it. If the namespace is being
destroyed, return -ENODEV early, after releasing the bearer reference.

[1]: https://lore.kernel.org/all/68342b55.a70a0220.253bc2.0091.GAE@google.com/T/#m12019cf9ae77e1954f666914640efa36d52704a2

Reported-by: syzbot+f0c4a4aba757549ae26c@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/all/68342b55.a70a0220.253bc2.0091.GAE@google.com/T/#m12019cf9ae77e1954f666914640efa36d52704a2
Fixes: e27902461713 ("net/tipc: fix slab-use-after-free Read in tipc_aead_encrypt_done")
Signed-off-by: Charalampos Mitrodimas <charmitro@posteo.net>
Reviewed-by: Tung Nguyen <tung.quang.nguyen@est.tech>
Link: https://patch.msgid.link/20250527-net-tipc-warning-v2-1-df3dc398a047@posteo.net
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
tipc: use kfree_sensitive() for aead cleanup 2025-05-28T00:31:42+00:00 Zilin Guan zilin@seu.edu.cn 2025-05-23T11:47:17+00:00 c8ef20fe7274c5766a317f9193b70bed717b6b3d The tipc_aead_free() function currently uses kfree() to release the aead structure. However, this structure contains sensitive information, such as key's SALT value, which should be securely erased from memory to prevent potential leakage. To enhance security, replace kfree() with kfree_sensitive() when freeing the aead structure. This change ensures that sensitive data is explicitly cleared before memory deallocation, aligning with the approach used in tipc_aead_init() and adhering to best practices for handling confidential information. Signed-off-by: Zilin Guan <zilin@seu.edu.cn> Reviewed-by: Tung Nguyen <tung.quang.nguyen@est.tech> Link: https://patch.msgid.link/20250523114717.4021518-1-zilin@seu.edu.cn Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
The tipc_aead_free() function currently uses kfree() to release the aead
structure. However, this structure contains sensitive information, such
as key's SALT value, which should be securely erased from memory to
prevent potential leakage.

To enhance security, replace kfree() with kfree_sensitive() when freeing
the aead structure. This change ensures that sensitive data is explicitly
cleared before memory deallocation, aligning with the approach used in
tipc_aead_init() and adhering to best practices for handling confidential
information.

Signed-off-by: Zilin Guan <zilin@seu.edu.cn>
Reviewed-by: Tung Nguyen <tung.quang.nguyen@est.tech>
Link: https://patch.msgid.link/20250523114717.4021518-1-zilin@seu.edu.cn
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
net/tipc: fix slab-use-after-free Read in tipc_aead_encrypt_done 2025-05-22T09:33:12+00:00 Wang Liang wangliang74@huawei.com 2025-05-20T10:14:04+00:00 e279024617134c94fd3e37470156534d5f2b3472 Syzbot reported a slab-use-after-free with the following call trace: ================================================================== BUG: KASAN: slab-use-after-free in tipc_aead_encrypt_done+0x4bd/0x510 net/tipc/crypto.c:840 Read of size 8 at addr ffff88807a733000 by task kworker/1:0/25 Call Trace: kasan_report+0xd9/0x110 mm/kasan/report.c:601 tipc_aead_encrypt_done+0x4bd/0x510 net/tipc/crypto.c:840 crypto_request_complete include/crypto/algapi.h:266 aead_request_complete include/crypto/internal/aead.h:85 cryptd_aead_crypt+0x3b8/0x750 crypto/cryptd.c:772 crypto_request_complete include/crypto/algapi.h:266 cryptd_queue_worker+0x131/0x200 crypto/cryptd.c:181 process_one_work+0x9fb/0x1b60 kernel/workqueue.c:3231 Allocated by task 8355: kzalloc_noprof include/linux/slab.h:778 tipc_crypto_start+0xcc/0x9e0 net/tipc/crypto.c:1466 tipc_init_net+0x2dd/0x430 net/tipc/core.c:72 ops_init+0xb9/0x650 net/core/net_namespace.c:139 setup_net+0x435/0xb40 net/core/net_namespace.c:343 copy_net_ns+0x2f0/0x670 net/core/net_namespace.c:508 create_new_namespaces+0x3ea/0xb10 kernel/nsproxy.c:110 unshare_nsproxy_namespaces+0xc0/0x1f0 kernel/nsproxy.c:228 ksys_unshare+0x419/0x970 kernel/fork.c:3323 __do_sys_unshare kernel/fork.c:3394 Freed by task 63: kfree+0x12a/0x3b0 mm/slub.c:4557 tipc_crypto_stop+0x23c/0x500 net/tipc/crypto.c:1539 tipc_exit_net+0x8c/0x110 net/tipc/core.c:119 ops_exit_list+0xb0/0x180 net/core/net_namespace.c:173 cleanup_net+0x5b7/0xbf0 net/core/net_namespace.c:640 process_one_work+0x9fb/0x1b60 kernel/workqueue.c:3231 After freed the tipc_crypto tx by delete namespace, tipc_aead_encrypt_done may still visit it in cryptd_queue_worker workqueue. I reproduce this issue by: ip netns add ns1 ip link add veth1 type veth peer name veth2 ip link set veth1 netns ns1 ip netns exec ns1 tipc bearer enable media eth dev veth1 ip netns exec ns1 tipc node set key this_is_a_master_key master ip netns exec ns1 tipc bearer disable media eth dev veth1 ip netns del ns1 The key of reproduction is that, simd_aead_encrypt is interrupted, leading to crypto_simd_usable() return false. Thus, the cryptd_queue_worker is triggered, and the tipc_crypto tx will be visited. tipc_disc_timeout tipc_bearer_xmit_skb tipc_crypto_xmit tipc_aead_encrypt crypto_aead_encrypt // encrypt() simd_aead_encrypt // crypto_simd_usable() is false child = &ctx->cryptd_tfm->base; simd_aead_encrypt crypto_aead_encrypt // encrypt() cryptd_aead_encrypt_enqueue cryptd_aead_enqueue cryptd_enqueue_request // trigger cryptd_queue_worker queue_work_on(smp_processor_id(), cryptd_wq, &cpu_queue->work) Fix this by holding net reference count before encrypt. Reported-by: syzbot+55c12726619ff85ce1f6@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=55c12726619ff85ce1f6 Fixes: fc1b6d6de220 ("tipc: introduce TIPC encryption & authentication") Signed-off-by: Wang Liang <wangliang74@huawei.com> Link: https://patch.msgid.link/20250520101404.1341730-1-wangliang74@huawei.com Signed-off-by: Paolo Abeni <pabeni@redhat.com> 
Syzbot reported a slab-use-after-free with the following call trace:

  ==================================================================
  BUG: KASAN: slab-use-after-free in tipc_aead_encrypt_done+0x4bd/0x510 net/tipc/crypto.c:840
  Read of size 8 at addr ffff88807a733000 by task kworker/1:0/25

  Call Trace:
   kasan_report+0xd9/0x110 mm/kasan/report.c:601
   tipc_aead_encrypt_done+0x4bd/0x510 net/tipc/crypto.c:840
   crypto_request_complete include/crypto/algapi.h:266
   aead_request_complete include/crypto/internal/aead.h:85
   cryptd_aead_crypt+0x3b8/0x750 crypto/cryptd.c:772
   crypto_request_complete include/crypto/algapi.h:266
   cryptd_queue_worker+0x131/0x200 crypto/cryptd.c:181
   process_one_work+0x9fb/0x1b60 kernel/workqueue.c:3231

  Allocated by task 8355:
   kzalloc_noprof include/linux/slab.h:778
   tipc_crypto_start+0xcc/0x9e0 net/tipc/crypto.c:1466
   tipc_init_net+0x2dd/0x430 net/tipc/core.c:72
   ops_init+0xb9/0x650 net/core/net_namespace.c:139
   setup_net+0x435/0xb40 net/core/net_namespace.c:343
   copy_net_ns+0x2f0/0x670 net/core/net_namespace.c:508
   create_new_namespaces+0x3ea/0xb10 kernel/nsproxy.c:110
   unshare_nsproxy_namespaces+0xc0/0x1f0 kernel/nsproxy.c:228
   ksys_unshare+0x419/0x970 kernel/fork.c:3323
   __do_sys_unshare kernel/fork.c:3394

  Freed by task 63:
   kfree+0x12a/0x3b0 mm/slub.c:4557
   tipc_crypto_stop+0x23c/0x500 net/tipc/crypto.c:1539
   tipc_exit_net+0x8c/0x110 net/tipc/core.c:119
   ops_exit_list+0xb0/0x180 net/core/net_namespace.c:173
   cleanup_net+0x5b7/0xbf0 net/core/net_namespace.c:640
   process_one_work+0x9fb/0x1b60 kernel/workqueue.c:3231

After freed the tipc_crypto tx by delete namespace, tipc_aead_encrypt_done
may still visit it in cryptd_queue_worker workqueue.

I reproduce this issue by:
  ip netns add ns1
  ip link add veth1 type veth peer name veth2
  ip link set veth1 netns ns1
  ip netns exec ns1 tipc bearer enable media eth dev veth1
  ip netns exec ns1 tipc node set key this_is_a_master_key master
  ip netns exec ns1 tipc bearer disable media eth dev veth1
  ip netns del ns1

The key of reproduction is that, simd_aead_encrypt is interrupted, leading
to crypto_simd_usable() return false. Thus, the cryptd_queue_worker is
triggered, and the tipc_crypto tx will be visited.

  tipc_disc_timeout
    tipc_bearer_xmit_skb
      tipc_crypto_xmit
        tipc_aead_encrypt
          crypto_aead_encrypt
            // encrypt()
            simd_aead_encrypt
              // crypto_simd_usable() is false
              child = &ctx->cryptd_tfm->base;

  simd_aead_encrypt
    crypto_aead_encrypt
      // encrypt()
      cryptd_aead_encrypt_enqueue
        cryptd_aead_enqueue
          cryptd_enqueue_request
            // trigger cryptd_queue_worker
            queue_work_on(smp_processor_id(), cryptd_wq, &cpu_queue->work)

Fix this by holding net reference count before encrypt.

Reported-by: syzbot+55c12726619ff85ce1f6@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=55c12726619ff85ce1f6
Fixes: fc1b6d6de220 ("tipc: introduce TIPC encryption & authentication")
Signed-off-by: Wang Liang <wangliang74@huawei.com>
Link: https://patch.msgid.link/20250520101404.1341730-1-wangliang74@huawei.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
tipc: re-order conditions in tipc_crypto_key_rcv() 2025-01-20T12:18:26+00:00 Dan Carpenter dan.carpenter@linaro.org 2025-01-17T09:36:14+00:00 5fe71fda89745fc3cd95f70d06e9162b595c3702 On a 32bit system the "keylen + sizeof(struct tipc_aead_key)" math could have an integer wrapping issue. It doesn't matter because the "keylen" is checked on the next line, but just to make life easier for static analysis tools, let's re-order these conditions and avoid the integer overflow. Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org> Reviewed-by: Simon Horman <horms@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net> 
On a 32bit system the "keylen + sizeof(struct tipc_aead_key)" math could
have an integer wrapping issue.  It doesn't matter because the "keylen"
is checked on the next line, but just to make life easier for static
analysis tools, let's re-order these conditions and avoid the integer
overflow.

Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
tipc: fix a potential deadlock on &tx->lock 2023-10-04T20:24:12+00:00 Chengfeng Ye dg573847474@gmail.com 2023-09-27T18:14:14+00:00 08e50cf071847323414df0835109b6f3560d44f5 It seems that tipc_crypto_key_revoke() could be be invoked by wokequeue tipc_crypto_work_rx() under process context and timer/rx callback under softirq context, thus the lock acquisition on &tx->lock seems better use spin_lock_bh() to prevent possible deadlock. This flaw was found by an experimental static analysis tool I am developing for irq-related deadlock. tipc_crypto_work_rx() <workqueue> --> tipc_crypto_key_distr() --> tipc_bcast_xmit() --> tipc_bcbase_xmit() --> tipc_bearer_bc_xmit() --> tipc_crypto_xmit() --> tipc_ehdr_build() --> tipc_crypto_key_revoke() --> spin_lock(&tx->lock) <timer interrupt> --> tipc_disc_timeout() --> tipc_bearer_xmit_skb() --> tipc_crypto_xmit() --> tipc_ehdr_build() --> tipc_crypto_key_revoke() --> spin_lock(&tx->lock) <deadlock here> Signed-off-by: Chengfeng Ye <dg573847474@gmail.com> Reviewed-by: Jacob Keller <jacob.e.keller@intel.com> Acked-by: Jon Maloy <jmaloy@redhat.com> Fixes: fc1b6d6de220 ("tipc: introduce TIPC encryption & authentication") Link: https://lore.kernel.org/r/20230927181414.59928-1-dg573847474@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
It seems that tipc_crypto_key_revoke() could be be invoked by
wokequeue tipc_crypto_work_rx() under process context and
timer/rx callback under softirq context, thus the lock acquisition
on &tx->lock seems better use spin_lock_bh() to prevent possible
deadlock.

This flaw was found by an experimental static analysis tool I am
developing for irq-related deadlock.

tipc_crypto_work_rx() <workqueue>
--> tipc_crypto_key_distr()
--> tipc_bcast_xmit()
--> tipc_bcbase_xmit()
--> tipc_bearer_bc_xmit()
--> tipc_crypto_xmit()
--> tipc_ehdr_build()
--> tipc_crypto_key_revoke()
--> spin_lock(&tx->lock)
<timer interrupt>
   --> tipc_disc_timeout()
   --> tipc_bearer_xmit_skb()
   --> tipc_crypto_xmit()
   --> tipc_ehdr_build()
   --> tipc_crypto_key_revoke()
   --> spin_lock(&tx->lock) <deadlock here>

Signed-off-by: Chengfeng Ye <dg573847474@gmail.com>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Acked-by: Jon Maloy <jmaloy@redhat.com>
Fixes: fc1b6d6de220 ("tipc: introduce TIPC encryption & authentication")
Link: https://lore.kernel.org/r/20230927181414.59928-1-dg573847474@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
tipc: check return value of pskb_trim() 2023-07-27T08:46:05+00:00 Yuanjun Gong ruc_gongyuanjun@163.com 2023-07-25T06:48:10+00:00 e46e06ffc6d667a89b979701288e2264f45e6a7b goto free_skb if an unexpected result is returned by pskb_tirm() in tipc_crypto_rcv_complete(). Fixes: fc1b6d6de220 ("tipc: introduce TIPC encryption & authentication") Signed-off-by: Yuanjun Gong <ruc_gongyuanjun@163.com> Reviewed-by: Tung Nguyen <tung.q.nguyen@dektech.com.au> Link: https://lore.kernel.org/r/20230725064810.5820-1-ruc_gongyuanjun@163.com Signed-off-by: Paolo Abeni <pabeni@redhat.com> 
goto free_skb if an unexpected result is returned by pskb_tirm()
in tipc_crypto_rcv_complete().

Fixes: fc1b6d6de220 ("tipc: introduce TIPC encryption & authentication")
Signed-off-by: Yuanjun Gong <ruc_gongyuanjun@163.com>
Reviewed-by: Tung Nguyen <tung.q.nguyen@dektech.com.au>
Link: https://lore.kernel.org/r/20230725064810.5820-1-ruc_gongyuanjun@163.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
tipc: Remove completion function scaffolding 2023-02-13T10:35:15+00:00 Herbert Xu herbert@gondor.apana.org.au 2023-02-06T10:22:42+00:00 65cb4657bac776967f1f794fb45d2fa419565c63 This patch removes the temporary scaffolding now that the comletion function signature has been converted. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> 
This patch removes the temporary scaffolding now that the comletion
function signature has been converted.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
tipc: Add scaffolding to change completion function signature 2023-02-13T10:34:48+00:00 Herbert Xu herbert@gondor.apana.org.au 2023-02-06T10:22:25+00:00 1dbab1312254602175c805863eaace59ebf162ba This patch adds temporary scaffolding so that the Crypto API completion function can take a void * instead of crypto_async_request. Once affected users have been converted this can be removed. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> 
This patch adds temporary scaffolding so that the Crypto API
completion function can take a void * instead of crypto_async_request.
Once affected users have been converted this can be removed.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
tipc: re-fetch skb cb after tipc_msg_validate 2022-11-29T02:07:31+00:00 Xin Long lucien.xin@gmail.com 2022-11-25T17:46:43+00:00 3067bc61fcfe3081bf4807ce65560f499e895e77 As the call trace shows, the original skb was freed in tipc_msg_validate(), and dereferencing the old skb cb would cause an use-after-free crash. BUG: KASAN: use-after-free in tipc_crypto_rcv_complete+0x1835/0x2240 [tipc] Call Trace: <IRQ> tipc_crypto_rcv_complete+0x1835/0x2240 [tipc] tipc_crypto_rcv+0xd32/0x1ec0 [tipc] tipc_rcv+0x744/0x1150 [tipc] ... Allocated by task 47078: kmem_cache_alloc_node+0x158/0x4d0 __alloc_skb+0x1c1/0x270 tipc_buf_acquire+0x1e/0xe0 [tipc] tipc_msg_create+0x33/0x1c0 [tipc] tipc_link_build_proto_msg+0x38a/0x2100 [tipc] tipc_link_timeout+0x8b8/0xef0 [tipc] tipc_node_timeout+0x2a1/0x960 [tipc] call_timer_fn+0x2d/0x1c0 ... Freed by task 47078: tipc_msg_validate+0x7b/0x440 [tipc] tipc_crypto_rcv_complete+0x4b5/0x2240 [tipc] tipc_crypto_rcv+0xd32/0x1ec0 [tipc] tipc_rcv+0x744/0x1150 [tipc] This patch fixes it by re-fetching the skb cb from the new allocated skb after calling tipc_msg_validate(). Fixes: fc1b6d6de220 ("tipc: introduce TIPC encryption & authentication") Reported-by: Shuang Li <shuali@redhat.com> Signed-off-by: Xin Long <lucien.xin@gmail.com> Link: https://lore.kernel.org/r/1b1cdba762915325bd8ef9a98d0276eb673df2a5.1669398403.git.lucien.xin@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
As the call trace shows, the original skb was freed in tipc_msg_validate(),
and dereferencing the old skb cb would cause an use-after-free crash.

  BUG: KASAN: use-after-free in tipc_crypto_rcv_complete+0x1835/0x2240 [tipc]
  Call Trace:
   <IRQ>
   tipc_crypto_rcv_complete+0x1835/0x2240 [tipc]
   tipc_crypto_rcv+0xd32/0x1ec0 [tipc]
   tipc_rcv+0x744/0x1150 [tipc]
  ...
  Allocated by task 47078:
   kmem_cache_alloc_node+0x158/0x4d0
   __alloc_skb+0x1c1/0x270
   tipc_buf_acquire+0x1e/0xe0 [tipc]
   tipc_msg_create+0x33/0x1c0 [tipc]
   tipc_link_build_proto_msg+0x38a/0x2100 [tipc]
   tipc_link_timeout+0x8b8/0xef0 [tipc]
   tipc_node_timeout+0x2a1/0x960 [tipc]
   call_timer_fn+0x2d/0x1c0
  ...
  Freed by task 47078:
   tipc_msg_validate+0x7b/0x440 [tipc]
   tipc_crypto_rcv_complete+0x4b5/0x2240 [tipc]
   tipc_crypto_rcv+0xd32/0x1ec0 [tipc]
   tipc_rcv+0x744/0x1150 [tipc]

This patch fixes it by re-fetching the skb cb from the new allocated skb
after calling tipc_msg_validate().

Fixes: fc1b6d6de220 ("tipc: introduce TIPC encryption & authentication")
Reported-by: Shuang Li <shuali@redhat.com>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Link: https://lore.kernel.org/r/1b1cdba762915325bd8ef9a98d0276eb673df2a5.1669398403.git.lucien.xin@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
tipc: fix a bit overflow in tipc_crypto_key_rcv() 2022-02-13T12:12:25+00:00 Hangyu Hua hbh25y@gmail.com 2022-02-11T04:55:10+00:00 143de8d97d79316590475dc2a84513c63c863ddf msg_data_sz return a 32bit value, but size is 16bit. This may lead to a bit overflow. Signed-off-by: Hangyu Hua <hbh25y@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
msg_data_sz return a 32bit value, but size is 16bit. This may lead to a
bit overflow.

Signed-off-by: Hangyu Hua <hbh25y@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>