kernel/linux.git/net/bluetooth/iso.c, branch v7.1.12

Bluetooth: ISO: zero the sockaddr before returning it in getname

2026-08-27T12:34:41+00:00

commit 884cf2cc957da7ac178a0e6c6c69ddfec0481cc8 upstream. iso_sock_getname() fills a struct sockaddr_iso in place and returns its size without clearing it first, so bytes it does not write are copied to user space from the kernel stack. The getsockname(2) and getpeername(2) paths both run through do_getsockname(), which hands getname() an uninitialized sockaddr_storage on the stack and copies back up to the number of bytes getname() returns, so the driver has to initialize every byte it accounts for. Two ranges are left uninitialized: - struct sockaddr_iso is 10 bytes but only 9 are written (family, iso_bdaddr, iso_bdaddr_type), leaking the trailing pad byte on every call. - for a broadcast peer (BIS_LINK or PA_LINK) the returned length grows by sizeof(struct sockaddr_iso_bc), but only bc_sid, bc_num_bis and bc_bis are filled; bc_bdaddr and bc_bdaddr_type, the first 7 bytes of that structure, are never written. An unprivileged process can open a BTPROTO_ISO socket and reach the pad leak with getsockname(); the broadcast leak needs an established BIS/PA connection. l2cap and rfcomm already memset their sockaddr in getname for the same reason; do the same here. Fixes: ccf74f2390d6 ("Bluetooth: Add BTPROTO_ISO socket type") Fixes: 0a766a0affb5 ("Bluetooth: ISO: Fix getpeername not returning sockaddr_iso_bc fields") Cc: stable@vger.kernel.org Signed-off-by: Ali Ahmet Memis Signed-off-by: Luiz Augusto von Dentz Signed-off-by: Greg Kroah-Hartman

Bluetooth: ISO: do not force BT_LISTEN after a failed BIG sync

2026-08-27T12:34:41+00:00

commit 9838a80096ba472d5e03057136a112631aabae6e upstream. iso_sock_recvmsg() handles the deferred setup of a broadcast sink by dropping the socket lock, calling iso_conn_big_sync() and taking the lock again: release_sock(sk); iso_conn_big_sync(sk); lock_sock(sk); sk->sk_state = BT_LISTEN; The state is written unconditionally, but iso_conn_big_sync() returns void and has paths that do nothing at all: hci_get_route() may fail, and after re-acquiring the socket lock the connection may already be gone, in which case it bails out without ever issuing an LE BIG Create Sync. While the lock is dropped the connection can be torn down, for example when the controller reports HCI_EV_LE_PA_SYNC_LOST: hci_le_pa_sync_lost_evt() hci_disconn_cfm() -> iso_disconn_cfm() -> iso_conn_del() iso_chan_del() iso_pi(sk)->conn = NULL sk->sk_state = BT_CLOSED sock_set_flag(sk, SOCK_ZAPPED) iso_conn_big_sync() then finds conn == NULL and returns, but the caller still overwrites the BT_CLOSED that iso_chan_del() has just set. The socket ends up marked BT_LISTEN with no connection, so recvmsg() reports success for a setup that never happened and a later accept() waits for BIS connections that can never arrive instead of failing. A concurrent shutdown() reaches the same write by another route: __iso_sock_close() takes the BT_CONNECT2 PA sync path to iso_sock_disconn(), which sets BT_DISCONN but leaves conn and conn->hcon in place, so iso_conn_big_sync() succeeds and BT_LISTEN is written over BT_DISCONN. Both the BT_CONNECT2 and the BT_CONNECTED case write the state the same way. Let iso_conn_big_sync() report whether the BIG sync was started, and only move the socket to BT_LISTEN when it was and when the state has not changed while the lock was dropped, mirroring what the BT_CONNECT case of the same switch already does with iso_connect_cis(). Both conditions are needed, the error alone does not cover the shutdown() race. This corrupts the socket state machine only, it is not a memory safety issue. KASAN and lockdep stayed quiet in all of the runs below. Reproduced with an emulated controller over /dev/vhci on a KASAN + PROVE_LOCKING kernel. A PA sync broadcast sink socket is driven to BT_CONNECT2 and recvmsg() on it is raced against teardown, with a debug delay inside the lock-dropped section to widen the window: - HCI_EV_LE_PA_SYNC_LOST injected: 64 of 64 rounds left the socket in BT_LISTEN with the connection gone, recvmsg() returned 0 and accept() on that fd returned EAGAIN, which iso_sock_accept() can only do while the socket is BT_LISTEN. With this patch, 0 of 64, recvmsg() returns an error and accept() returns EBADFD. - shutdown() instead of a controller event: 24 of 32 rounds wedged in BT_LISTEN, 0 of 32 with this patch. With only the error check in place and a short window, one round still wedged while recvmsg() returned 0, which is the case the state re-check covers. An unraced control round behaves the same before and after: recvmsg() returns 0, the socket reaches BT_LISTEN and an LE BIG Create Sync is issued. Fixes: 7a17308c1788 ("Bluetooth: iso: Fix circular lock in iso_conn_big_sync") Cc: stable@vger.kernel.org Signed-off-by: Ali Ahmet Memis Signed-off-by: Luiz Augusto von Dentz Signed-off-by: Greg Kroah-Hartman

Bluetooth: ISO: fix race of kfree vs kref_get_unless_zero

2026-08-09T18:26:33+00:00

[ Upstream commit af24e338bf5dafb80f42baa9a0b9e9b57b1c5d9c ] hci_conn::iso_data is accessed and modified without lock or RCU. This leads to a race [Task hdev->workqueue] [Task 2] iso_recv iso_conn_put(conn) conn = LOAD hcon->iso_data iso_conn_free(conn) iso_conn_hold_unless_zero(conn) hcon->iso_data = NULL kfree(conn) kref_get_unless_zero(&conn->ref) /* UAF */ and also to races in iso_conn_add() vs. iso_conn_free(). Fix by adding spinlock hci_conn::proto_lock and using it to guard hci_conn::iso_data. Fixes: dc26097bdb86 ("Bluetooth: ISO: Use kref to track lifetime of iso_conn") Signed-off-by: Pauli Virtanen Signed-off-by: Luiz Augusto von Dentz Signed-off-by: Sasha Levin

Bluetooth: ISO: fix refcounting of iso_conn

2026-08-09T18:26:33+00:00

[ Upstream commit fdfde532ab1caa165fcd8985001157ac8b4db365 ] iso_conn_del() and iso_chan_del() have a race that results to double-put of iso_conn: [Task hdev->workqueue] [Task 2] iso_conn_del iso_chan_del iso_conn_hold_unless_zero iso_conn_lock iso_conn_lock conn->sk = NULL iso_conn_unlock sk = iso_sock_hold(conn) <---------´ if (!sk) iso_conn_put iso_conn_put iso_conn_put /* UAF */ The extra put for !sk in iso_conn_del() is currently required since failing iso_chan_add() may leave iso_conn not associated with any sk. Fix by having iso_pi(sk)->conn own refcount when non-NULL, so iso_conn_del does not need to put it. Adjust the iso_conn_add() refcounting so that conn is put if it does not get associated with an sk. Fixes: dc26097bdb86 ("Bluetooth: ISO: Use kref to track lifetime of iso_conn") Signed-off-by: Pauli Virtanen Signed-off-by: Luiz Augusto von Dentz Signed-off-by: Sasha Levin

Bluetooth: ISO: ensure no dangling hcon references in iso_conn

2026-08-09T18:26:33+00:00

[ Upstream commit aa9f7cb2bd3a2be998ceb739fc9a2f986eba43eb ] After iso_conn_del(), ISO sockets should not dereference the hcon any more. Currently, clearing iso_conn::hcon relies on iso_conn_del() releasing the last reference to the iso_conn. Simplify this by explicitly clearing conn->hcon in iso_conn_del(), to avoid more complex reasoning on races about who holds the last reference. Signed-off-by: Pauli Virtanen Signed-off-by: Luiz Augusto von Dentz Stable-dep-of: fdfde532ab1c ("Bluetooth: ISO: fix refcounting of iso_conn") Signed-off-by: Sasha Levin

Bluetooth: ISO: avoid deadlocks in iso_sock_timeout

2026-08-09T18:26:33+00:00

[ Upstream commit 200fa1629c57a3ca2b03d3ca63fd3a9bfd910c43 ] iso_sock_timeout() takes lock_sock, so sync disabling the timer while holding that lock may deadlock. iso_sock_timeout() may also run concurrently with iso_conn_del(), which leads to UAF [Task 1] [Task hdev->workqueue] iso_sock_timeout iso_conn_del iso_conn_hold_unless_zero iso_chan_del `------------> iso_conn_put caller frees hcon iso_conn_put iso_conn_free conn->hcon->iso_data = NULL; /* UAF */ Fix the deadlock by removing the disable from the lock_sock sections. Move the timer from iso_conn to iso_pinfo to decouple it from iso_conn which may need to be freed in lock_sock section. Convert some of the clear_timer to disable_timer. Fixes: dc26097bdb86 ("Bluetooth: ISO: Use kref to track lifetime of iso_conn") Signed-off-by: Pauli Virtanen Signed-off-by: Luiz Augusto von Dentz Signed-off-by: Sasha Levin

Bluetooth: ISO: fix leaking sk after socket release

2026-08-09T18:26:33+00:00

[ Upstream commit ce57442a379212fe3fda59c9437ee8217eceb5b1 ] iso_sock_kill() tests !sock_flag(sk, SOCK_ZAPPED) || sk->sk_socket || sock_flag(sk, SOCK_DEAD) for early return, but this is always true since sock_orphan(sk) sets SOCK_DEAD, so the sk reference released by socket always leaks, iso_sock_destruct is never called. The socket reference also leaks when __iso_sock_close() does not set SOCK_ZAPPED, since iso_conn_del() does not call iso_sock_kill() after zapping. Fix by replacing SOCK_DEAD by BT_SK_KILLED flag that is not used for something else, and lock_sock to ensure iso_sock_kill() puts sk only after socket release only once. Release and iso_conn_del may run concurrently. Call iso_sock_kill() from iso_conn_del() to clean sk up after zapping. Remove call to iso_sock_kill() from iso_sock_close(), as it's generally no-op there. Fixes: ccf74f2390d6 ("Bluetooth: Add BTPROTO_ISO socket type") Signed-off-by: Pauli Virtanen Signed-off-by: Luiz Augusto von Dentz Signed-off-by: Sasha Levin

Bluetooth: ISO: hold sk properly in iso_conn_ready

2026-08-09T18:26:33+00:00

[ Upstream commit 0d255e63fcf3f13a570d7ac11678fa1164ac015c ] sk deref in iso_conn_ready must be done either under conn->lock, or holding a refcount, to avoid concurrent close. conn->sk is currently accessed without either: [Task 1] [Task 2] iso_sock_release iso_conn_ready sk = conn->sk lock_sock(sk) conn->sk = NULL lock_sock(sk) release_sock(sk) iso_sock_kill(sk) UAF on sk deref Fix possible UAF by holding sk refcount in iso_conn_ready(). Also recheck after lock_sock that the socket is still valid. Adjust locking so conn->sk is cleared only under lock_sock. Fixes: 27c24fda62b60 ("Bluetooth: switch to lock_sock in SCO") Signed-off-by: Pauli Virtanen Signed-off-by: Luiz Augusto von Dentz Signed-off-by: Sasha Levin

Bluetooth: ISO: validate sockaddr_iso first in iso_sock_rebind_bis()

2026-08-09T18:26:33+00:00

[ Upstream commit 4e20192d46a685d73e590a60a4a2419a0a8afcbf ] iso_sock_rebind_bis() updates socket iso_pi(sk)->bc_num_bis before validating the BIS values, so it's possible to end up with bc_num_bis inconsistent. Assign to iso_pi(sk)->bc_num_bis only after validation. Fixes: 80837140c1f2 ("Bluetooth: ISO: Allow binding a PA sync socket") Signed-off-by: Pauli Virtanen Signed-off-by: Luiz Augusto von Dentz Signed-off-by: Sasha Levin

Bluetooth: ISO: fix timeout vs sync_timeout typo in check_bcast_qos

2026-08-09T18:26:33+00:00

[ Upstream commit e9cb51813d79fc9aae4a2098aab3ab6ebd7fb6c8 ] In iso.c check_bcast_qos(), missing bcast.timeout is not set to its default value, and appears typoed as bcast.sync_timeout. Fix the typo. Fixes: b37cab587aa3 ("Bluetooth: ISO: Don't reject BT_ISO_QOS if parameters are unset") Signed-off-by: Pauli Virtanen Signed-off-by: Luiz Augusto von Dentz Signed-off-by: Sasha Levin