kernel/linux.git/net/tipc/crypto.c, branch v7.2-rc2

tipc: fix slab-use-after-free Read in tipc_aead_decrypt_done

2026-06-19T01:35:35+00:00

tipc_aead_decrypt() goes straight from tipc_bearer_hold(b) to crypto_aead_decrypt(req) without taking a reference on the netns, unlike the encrypt path. When crypto_aead_decrypt() is offloaded asynchronously (e.g. the SIMD aead wrapper queuing to cryptd), the cryptd worker runs tipc_aead_decrypt_done() later. If the bearer's netns is torn down in the meantime, cleanup_net() -> tipc_exit_net() -> tipc_crypto_stop() frees the per-netns tipc_crypto, and the completion then reads it: tipc_aead_decrypt_done() dereferences aead->crypto->stats and aead->crypto->net, and tipc_crypto_rcv_complete() dereferences aead->crypto->aead[] and the node table -- reading freed memory. Decoded KASAN splat (v7.1-rc7, CONFIG_KASAN_INLINE + TIPC + TIPC_CRYPTO): BUG: KASAN: slab-use-after-free in tipc_aead_decrypt_done (net/tipc/crypto.c:999) Read of size 8 at addr ffff8881056258a8 by task kworker/u16:2/51 Workqueue: events_unbound Call Trace: tipc_aead_decrypt_done (net/tipc/crypto.c:999) process_one_work (kernel/workqueue.c:3314) worker_thread (kernel/workqueue.c:3397 kernel/workqueue.c:3478) kthread (kernel/kthread.c:436) ret_from_fork (arch/x86/kernel/process.c:158) ret_from_fork_asm (arch/x86/entry/entry_64.S:245) Allocated by task 169: __kasan_kmalloc (mm/kasan/common.c:398 mm/kasan/common.c:415) tipc_crypto_start (net/tipc/crypto.c:1502) tipc_init_net (net/tipc/core.c:72) ops_init (net/core/net_namespace.c:137) setup_net (net/core/net_namespace.c:446) copy_net_ns (net/core/net_namespace.c:579) create_new_namespaces (kernel/nsproxy.c:132) __x64_sys_unshare (kernel/fork.c:3316) do_syscall_64 (arch/x86/entry/syscall_64.c:63) entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:121) Freed by task 8: kfree (mm/slub.c:6566) tipc_exit_net (net/tipc/core.c:119) cleanup_net (net/core/net_namespace.c:704) process_one_work (kernel/workqueue.c:3314) kthread (kernel/kthread.c:436) This is the same class of bug that commit e279024617134 ("net/tipc: fix slab-use-after-free Read in tipc_aead_encrypt_done") fixed for the encrypt side. The encrypt path takes maybe_get_net(aead->crypto->net) before crypto_aead_encrypt() and drops it with put_net() on the synchronous return paths and in tipc_aead_encrypt_done(); the -EINPROGRESS/-EBUSY return keeps the reference for the async callback to release. The decrypt path was left without the equivalent guard. Mirror the encrypt-side fix on the decrypt path: take a net reference before crypto_aead_decrypt() (failing with -ENODEV and the matching bearer put if it cannot be acquired), keep it across the -EINPROGRESS/-EBUSY async return, and drop it with put_net() on the synchronous success/error return and at the end of tipc_aead_decrypt_done(). Reproduced under KASAN on v7.1-rc7: a UDP bearer with a cluster key is flooded with crafted encrypted frames from an unknown peer (driving the cluster-key decrypt path) while the bearer's netns is repeatedly torn down. The completion must run asynchronously to outlive tipc_crypto_stop(); on x86 the stock aesni gcm(aes) now decrypts synchronously, so the async path was exercised via cryptd offload. The unguarded aead->crypto dereference in tipc_aead_decrypt_done() is the unpatched upstream path; tipc_aead_decrypt() still lacks maybe_get_net(aead->crypto->net), so the completion can outlive the free on any config where crypto_aead_decrypt() goes async. Found by 0sec automated security-research tooling (https://0sec.ai). Fixes: fc1b6d6de220 ("tipc: introduce TIPC encryption & authentication") Cc: stable@vger.kernel.org Signed-off-by: Doruk Tan Ozturk Reviewed-by: Alexander Lobakin Reviewed-by: Tung Nguyen Reviewed-by: Simon Horman Link: https://patch.msgid.link/20260617075818.37431-1-doruk@0sec.ai Signed-off-by: Jakub Kicinski

net: tipc: Use crypto_stdrng_get_bytes()

2026-04-03T00:56:12+00:00

Replace the sequence of crypto_get_default_rng(), crypto_rng_get_bytes(), and crypto_put_default_rng() with the equivalent helper function crypto_stdrng_get_bytes(). Signed-off-by: Eric Biggers Signed-off-by: Herbert Xu

Convert 'alloc_obj' family to use the new default GFP_KERNEL argument

2026-02-22T01:09:51+00:00

This was done entirely with mindless brute force, using git grep -l '\

treewide: Replace kmalloc with kmalloc_obj for non-scalar types

2026-02-21T09:02:28+00:00

This is the result of running the Coccinelle script from scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to avoid scalar types (which need careful case-by-case checking), and instead replace kmalloc-family calls that allocate struct or union object instances: Single allocations: kmalloc(sizeof(TYPE), ...) are replaced with: kmalloc_obj(TYPE, ...) Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...) are replaced with: kmalloc_objs(TYPE, COUNT, ...) Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...) are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...) (where TYPE may also be *VAR) The resulting allocations no longer return "void *", instead returning "TYPE *". Signed-off-by: Kees Cook

tipc: fix RCU dereference race in tipc_aead_users_dec()

2026-02-05T20:36:31+00:00

tipc_aead_users_dec() calls rcu_dereference(aead) twice: once to store in 'tmp' for the NULL check, and again inside the atomic_add_unless() call. Use the already-dereferenced 'tmp' pointer consistently, matching the correct pattern used in tipc_aead_users_inc() and tipc_aead_users_set(). Fixes: fc1b6d6de220 ("tipc: introduce TIPC encryption & authentication") Cc: stable@vger.kernel.org Reviewed-by: Eric Dumazet Signed-off-by: Daniel Hodges Link: https://patch.msgid.link/20260203145621.17399-1-git@danielhodges.dev Signed-off-by: Jakub Kicinski

tipc: use kfree_sensitive() for session key material

2026-02-03T01:46:51+00:00

The rx->skey field contains a struct tipc_aead_key with GCM-AES encryption keys used for TIPC cluster communication. Using plain kfree() leaves this sensitive key material in freed memory pages where it could potentially be recovered. Switch to kfree_sensitive() to ensure the key material is zeroed before the memory is freed. Fixes: 1ef6f7c9390f ("tipc: add automatic session key exchange") Signed-off-by: Daniel Hodges Link: https://patch.msgid.link/20260131180114.2121438-1-hodgesd@meta.com Signed-off-by: Jakub Kicinski

net: doc: Fix typos in docs

2025-10-03T17:24:14+00:00

Fix typos in doc comments. Signed-off-by: Bhanu Seshu Kumar Valluri Link: https://patch.msgid.link/20251001105715.50462-1-bhanuseshukumar@gmail.com Signed-off-by: Jakub Kicinski

net: tipc: fix refcount warning in tipc_aead_encrypt

2025-05-29T10:07:26+00:00

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 Reviewed-by: Tung Nguyen Link: https://patch.msgid.link/20250527-net-tipc-warning-v2-1-df3dc398a047@posteo.net Signed-off-by: Paolo Abeni

tipc: use kfree_sensitive() for aead cleanup

2025-05-28T00:31:42+00:00

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 Reviewed-by: Tung Nguyen Link: https://patch.msgid.link/20250523114717.4021518-1-zilin@seu.edu.cn Signed-off-by: Jakub Kicinski

net/tipc: fix slab-use-after-free Read in tipc_aead_encrypt_done

2025-05-22T09:33:12+00:00

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 Link: https://patch.msgid.link/20250520101404.1341730-1-wangliang74@huawei.com Signed-off-by: Paolo Abeni