kernel/git/next/linux-next.git/net/bluetooth/smp.c, branch stable

Bluetooth: L2CAP: Fix use-after-free in l2cap_sock_new_connection_cb()

2026-07-06T14:46:58+00:00

l2cap_sock_new_connection_cb() returned l2cap_pi(sk)->chan after release_sock(parent). Once the parent lock is dropped the newly enqueued child socket sk is reachable via the accept queue, so another task can accept and free it before the callback dereferences sk, resulting in a use-after-free. Rework the ->new_connection() op so the core, rather than the callback, owns the child channel's lifetime. The op now receives a pre-allocated new_chan and returns an errno instead of allocating and returning a channel. l2cap_new_connection() allocates the child channel and links it into the conn list via __l2cap_chan_add() before invoking the callback, so the conn-list reference keeps the channel alive once release_sock(parent) exposes the socket to other tasks. Channel configuration that was duplicated in l2cap_sock_init() and the various new_connection callbacks is consolidated into l2cap_chan_set_defaults(), which now inherits from the parent channel when one is supplied. Fixes: 8ffb929098a5 ("Bluetooth: Remove parent socket usage from l2cap_core.c") Cc: stable@kernel.org Assisted-by: Claude:claude-opus-4-8 Signed-off-by: Siwei Zhang Signed-off-by: Luiz Augusto von Dentz

Bluetooth: Add SPDX id lines to some source files

2026-06-11T18:24:41+00:00

Many bluetooth source files are missing SPDX-License-Identifier lines. Add appropriate IDs to these files, and remove other license lines from the headers. Leave the warranty disclaimer in files where the license ID is GPL-2.0 but the wording of the disclaimer is slightly different from that of the GPL v2 disclaimer. It is not different enough to cause licensing conflicts, but is kept to honor the original contributors' legal intent. Signed-off-by: Tim Bird Signed-off-by: Luiz Augusto von Dentz

Bluetooth: SMP: Use AES-CMAC library API

2026-06-11T18:24:38+00:00

Now that AES-CMAC has a library API, convert net/bluetooth/smp.c to use it instead of the "cmac(aes)" crypto_shash. Since the library API doesn't require dynamic memory allocation, we no longer need to pass a crypto_shash object down the call stack and can simply allocate the aes_cmac_key on the stack in smp_aes_cmac() (renamed from aes_cmac()). The result is simpler and faster code that no longer relies on the error-prone loading of algorithms by name. Note that the maximum stack usage actually decreases slightly, despite the expanded AES key being moved to the stack. This is because the old code called crypto_shash_tfm_digest(), which allocates 384 bytes on the stack for a maximally-sized hash descriptor for any algorithm. The new code instead declares a 288-byte aes_cmac_key, then calls aes_cmac() which declares a 32-byte aes_cmac_ctx. Since 288 + 32 < 384, the maximum stack usage decreases. I.e. the entire expanded AES key easily fits in the space that the generic crypto API was wasting before. I didn't add zeroization of the aes_cmac_key, since smp_aes_cmac() already copies the raw key to the stack without zeroizing it. Reviewed-by: Ard Biesheuvel Signed-off-by: Eric Biggers Signed-off-by: Luiz Augusto von Dentz

Bluetooth: SMP: derive legacy responder STK authentication from MITM state

2026-04-01T20:48:06+00:00

The legacy responder path in smp_random() currently labels the stored STK as authenticated whenever pending_sec_level is BT_SECURITY_HIGH. That reflects what the local service requested, not what the pairing flow actually achieved. For Just Works/Confirm legacy pairing, SMP_FLAG_MITM_AUTH stays clear and the resulting STK should remain unauthenticated even if the local side requested HIGH security. Use the established MITM state when storing the responder STK so the key metadata matches the pairing result. This also keeps the legacy path aligned with the Secure Connections code, which already treats JUST_WORKS/JUST_CFM as unauthenticated. Fixes: fff3490f4781 ("Bluetooth: Fix setting correct authentication information for SMP STK") Cc: stable@vger.kernel.org Signed-off-by: Oleh Konko Signed-off-by: Luiz Augusto von Dentz

Bluetooth: SMP: force responder MITM requirements before building the pairing response

2026-04-01T20:47:43+00:00

smp_cmd_pairing_req() currently builds the pairing response from the initiator auth_req before enforcing the local BT_SECURITY_HIGH requirement. If the initiator omits SMP_AUTH_MITM, the response can also omit it even though the local side still requires MITM. tk_request() then sees an auth value without SMP_AUTH_MITM and may select JUST_CFM, making method selection inconsistent with the pairing policy the responder already enforces. When the local side requires HIGH security, first verify that MITM can be achieved from the IO capabilities and then force SMP_AUTH_MITM in the response in both rsp.auth_req and auth. This keeps the responder auth bits and later method selection aligned. Fixes: 2b64d153a0cc ("Bluetooth: Add MITM mechanism to LE-SMP") Cc: stable@vger.kernel.org Suggested-by: Luiz Augusto von Dentz Signed-off-by: Oleh Konko Signed-off-by: Luiz Augusto von Dentz

Bluetooth: SMP: make SM/PER/KDU/BI-04-C happy

2026-03-12T19:26:30+00:00

The last test step ("Test with Invalid public key X and Y, all set to 0") expects to get an "DHKEY check failed" instead of "unspecified". Fixes: 6d19628f539f ("Bluetooth: SMP: Fail if remote and local public keys are identical") Signed-off-by: Christian Eggers Signed-off-by: Luiz Augusto von Dentz

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

Bluetooth: SMP: Use new AES library API

2026-01-15T22:09:07+00:00

Switch from the old AES library functions (which use struct crypto_aes_ctx) to the new ones (which use struct aes_enckey). This eliminates the unnecessary computation and caching of the decryption round keys. The new AES en/decryption functions are also much faster and use AES instructions when supported by the CPU. Note that in addition to the change in the key preparation function and the key struct type itself, the change in the type of the key struct results in aes_encrypt() (which is temporarily a type-generic macro) calling the new encryption function rather than the old one. Acked-by: Ard Biesheuvel Link: https://lore.kernel.org/r/20260112192035.10427-20-ebiggers@kernel.org Signed-off-by: Eric Biggers

Bluetooth: SMP: Fix not generating mackey and ltk when repairing

2025-11-20T22:02:07+00:00

The change eed467b517e8 ("Bluetooth: fix passkey uninitialized when used") introduced a goto that bypasses the creation of temporary mackey and ltk which are later used by the likes of DHKey Check step. Later ffee202a78c2 ("Bluetooth: Always request for user confirmation for Just Works (LE SC)") which means confirm_hint is always set in case JUST_WORKS so the branch checking for an existing LTK becomes pointless as confirm_hint will always be set, so this just merge both cases of malicious or legitimate devices to be confirmed before continuing with the pairing procedure. Link: https://github.com/bluez/bluez/issues/1622 Fixes: eed467b517e8 ("Bluetooth: fix passkey uninitialized when used") Signed-off-by: Luiz Augusto von Dentz