linux-stable.git/net/bluetooth, branch v6.9.3 Linux kernel stable tree Bluetooth: hci_core: Fix not handling hdev->le_num_of_adv_sets=1 2024-05-30T07:44:41+00:00 Luiz Augusto von Dentz luiz.von.dentz@intel.com 2024-05-13T20:07:55+00:00 0baa80343e78b9b69bb14d23d1dfe032dc95ad93 [ Upstream commit e77f43d531af41e9ce299eab10dcae8fa5dbc293 ] If hdev->le_num_of_adv_sets is set to 1 it means that only handle 0x00 can be used, but since the MGMT interface instances start from 1 (instance 0 means all instances in case of MGMT_OP_REMOVE_ADVERTISING) the code needs to map the instance to handle otherwise users will not be able to advertise as instance 1 would attempt to use handle 0x01. Fixes: 1d0fac2c38ed ("Bluetooth: Use controller sets when available") Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit e77f43d531af41e9ce299eab10dcae8fa5dbc293 ]

If hdev->le_num_of_adv_sets is set to 1 it means that only handle 0x00
can be used, but since the MGMT interface instances start from 1
(instance 0 means all instances in case of MGMT_OP_REMOVE_ADVERTISING)
the code needs to map the instance to handle otherwise users will not be
able to advertise as instance 1 would attempt to use handle 0x01.

Fixes: 1d0fac2c38ed ("Bluetooth: Use controller sets when available")
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Bluetooth: hci_conn, hci_sync: Use __counted_by() to avoid -Wfamnae warnings 2024-05-30T07:44:41+00:00 Gustavo A. R. Silva gustavoars@kernel.org 2024-04-26T22:52:46+00:00 ec339f0c3472445003b47f28da951e119446146c [ Upstream commit c4585edf708edb5277a3cc4b8581ccb833f3307d ] Prepare for the coming implementation by GCC and Clang of the __counted_by attribute. Flexible array members annotated with __counted_by can have their accesses bounds-checked at run-time via CONFIG_UBSAN_BOUNDS (for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family functions). Also, -Wflex-array-member-not-at-end is coming in GCC-14, and we are getting ready to enable it globally. So, use the `DEFINE_FLEX()` helper for multiple on-stack definitions of a flexible structure where the size of the flexible-array member is known at compile-time, and refactor the rest of the code, accordingly. Notice that, due to the use of `__counted_by()` in `struct hci_cp_le_create_cis`, the for loop in function `hci_cs_le_create_cis()` had to be modified. Once the index `i`, through which `cp->cis[i]` is accessed, falls in the interval [0, cp->num_cis), `cp->num_cis` cannot be decremented all the way down to zero while accessing `cp->cis[]`: net/bluetooth/hci_event.c:4310: 4310 for (i = 0; cp->num_cis; cp->num_cis--, i++) { ... 4314 handle = __le16_to_cpu(cp->cis[i].cis_handle); otherwise, only half (one iteration before `cp->num_cis == i`) or half plus one (one iteration before `cp->num_cis < i`) of the items in the array will be accessed before running into an out-of-bounds issue. So, in order to avoid this, set `cp->num_cis` to zero just after the for loop. Also, make use of `aux_num_cis` variable to update `cmd->num_cis` after a `list_for_each_entry_rcu()` loop. With these changes, fix the following warnings: net/bluetooth/hci_sync.c:1239:56: warning: structure containing a flexible array member is not at the end of another structure [-Wflex-array-member-not-at-end] net/bluetooth/hci_sync.c:1415:51: warning: structure containing a flexible array member is not at the end of another structure [-Wflex-array-member-not-at-end] net/bluetooth/hci_sync.c:1731:51: warning: structure containing a flexible array member is not at the end of another structure [-Wflex-array-member-not-at-end] net/bluetooth/hci_sync.c:6497:45: warning: structure containing a flexible array member is not at the end of another structure [-Wflex-array-member-not-at-end] Link: https://github.com/KSPP/linux/issues/202 Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Stable-dep-of: e77f43d531af ("Bluetooth: hci_core: Fix not handling hdev->le_num_of_adv_sets=1") Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit c4585edf708edb5277a3cc4b8581ccb833f3307d ]

Prepare for the coming implementation by GCC and Clang of the
__counted_by attribute. Flexible array members annotated with
__counted_by can have their accesses bounds-checked at run-time
via CONFIG_UBSAN_BOUNDS (for array indexing) and CONFIG_FORTIFY_SOURCE
(for strcpy/memcpy-family functions).

Also, -Wflex-array-member-not-at-end is coming in GCC-14, and we are
getting ready to enable it globally.

So, use the `DEFINE_FLEX()` helper for multiple on-stack definitions
of a flexible structure where the size of the flexible-array member
is known at compile-time, and refactor the rest of the code,
accordingly.

Notice that, due to the use of `__counted_by()` in `struct
hci_cp_le_create_cis`, the for loop in function `hci_cs_le_create_cis()`
had to be modified. Once the index `i`, through which `cp->cis[i]` is
accessed, falls in the interval [0, cp->num_cis), `cp->num_cis` cannot
be decremented all the way down to zero while accessing `cp->cis[]`:

net/bluetooth/hci_event.c:4310:
4310    for (i = 0; cp->num_cis; cp->num_cis--, i++) {
                ...
4314            handle = __le16_to_cpu(cp->cis[i].cis_handle);

otherwise, only half (one iteration before `cp->num_cis == i`) or half
plus one (one iteration before `cp->num_cis < i`) of the items in the
array will be accessed before running into an out-of-bounds issue. So,
in order to avoid this, set `cp->num_cis` to zero just after the for
loop.

Also, make use of `aux_num_cis` variable to update `cmd->num_cis` after
a `list_for_each_entry_rcu()` loop.

With these changes, fix the following warnings:
net/bluetooth/hci_sync.c:1239:56: warning: structure containing a flexible
array member is not at the end of another structure
[-Wflex-array-member-not-at-end]
net/bluetooth/hci_sync.c:1415:51: warning: structure containing a flexible
array member is not at the end of another structure
[-Wflex-array-member-not-at-end]
net/bluetooth/hci_sync.c:1731:51: warning: structure containing a flexible
array member is not at the end of another structure
[-Wflex-array-member-not-at-end]
net/bluetooth/hci_sync.c:6497:45: warning: structure containing a flexible
array member is not at the end of another structure
[-Wflex-array-member-not-at-end]

Link: https://github.com/KSPP/linux/issues/202
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Stable-dep-of: e77f43d531af ("Bluetooth: hci_core: Fix not handling hdev->le_num_of_adv_sets=1")
Signed-off-by: Sasha Levin <sashal@kernel.org>
Bluetooth: HCI: Remove HCI_AMP support 2024-05-30T07:44:41+00:00 Luiz Augusto von Dentz luiz.von.dentz@intel.com 2024-05-06T22:33:52+00:00 af1d425b6dc67cd67809f835dd7afb6be4d43e03 [ Upstream commit 84a4bb6548a29326564f0e659fb8064503ecc1c7 ] Since BT_HS has been remove HCI_AMP controllers no longer has any use so remove it along with the capability of creating AMP controllers. Since we no longer need to differentiate between AMP and Primary controllers, as only HCI_PRIMARY is left, this also remove hdev->dev_type altogether. Fixes: e7b02296fb40 ("Bluetooth: Remove BT_HS") Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 84a4bb6548a29326564f0e659fb8064503ecc1c7 ]

Since BT_HS has been remove HCI_AMP controllers no longer has any use so
remove it along with the capability of creating AMP controllers.

Since we no longer need to differentiate between AMP and Primary
controllers, as only HCI_PRIMARY is left, this also remove
hdev->dev_type altogether.

Fixes: e7b02296fb40 ("Bluetooth: Remove BT_HS")
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Bluetooth: ISO: Make iso_get_sock_listen generic 2024-05-30T07:44:40+00:00 Iulia Tanasescu iulia.tanasescu@nxp.com 2024-04-02T11:39:30+00:00 c581c331100ad5fe1d332e541b6b854a56450898 [ Upstream commit 311527e9dafdcae0c5a20d62f4f84ad01b33b5f4 ] This makes iso_get_sock_listen more generic, to return matching socket in the state provided as argument. Signed-off-by: Iulia Tanasescu <iulia.tanasescu@nxp.com> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Stable-dep-of: a5b862c6a221 ("Bluetooth: L2CAP: Fix div-by-zero in l2cap_le_flowctl_init()") Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 311527e9dafdcae0c5a20d62f4f84ad01b33b5f4 ]

This makes iso_get_sock_listen more generic, to return matching socket
in the state provided as argument.

Signed-off-by: Iulia Tanasescu <iulia.tanasescu@nxp.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Stable-dep-of: a5b862c6a221 ("Bluetooth: L2CAP: Fix div-by-zero in l2cap_le_flowctl_init()")
Signed-off-by: Sasha Levin <sashal@kernel.org>
Bluetooth: compute LE flow credits based on recvbuf space 2024-05-30T07:44:40+00:00 Sebastian Urban surban@surban.net 2024-05-01T10:08:58+00:00 0c287656fce837201c295fc4f9747603593615b2 [ Upstream commit ce60b9231b66710b6ee24042ded26efee120ecfc ] Previously LE flow credits were returned to the sender even if the socket's receive buffer was full. This meant that no back-pressure was applied to the sender, thus it continued to send data, resulting in data loss without any error being reported. Furthermore, the amount of credits was essentially fixed to a small amount, leading to reduced performance. This is fixed by computing the number of returned LE flow credits based on the estimated available space in the receive buffer of an L2CAP socket. Consequently, if the receive buffer is full, no credits are returned until the buffer is read and thus cleared by user-space. Since the computation of available receive buffer space can only be performed approximately (due to sk_buff overhead) and the receive buffer size may be changed by user-space after flow credits have been sent, superfluous received data is temporary stored within l2cap_pinfo. This is necessary because Bluetooth LE provides no retransmission mechanism once the data has been acked by the physical layer. If receive buffer space estimation is not possible at the moment, we fall back to providing credits for one full packet as before. This is currently the case during connection setup, when MPS is not yet available. Fixes: b1c325c23d75 ("Bluetooth: Implement returning of LE L2CAP credits") Signed-off-by: Sebastian Urban <surban@surban.net> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit ce60b9231b66710b6ee24042ded26efee120ecfc ]

Previously LE flow credits were returned to the
sender even if the socket's receive buffer was
full. This meant that no back-pressure
was applied to the sender, thus it continued to
send data, resulting in data loss without any
error being reported. Furthermore, the amount
of credits was essentially fixed to a small
amount, leading to reduced performance.

This is fixed by computing the number of returned
LE flow credits based on the estimated available
space in the receive buffer of an L2CAP socket.
Consequently, if the receive buffer is full, no
credits are returned until the buffer is read and
thus cleared by user-space.

Since the computation of available receive buffer
space can only be performed approximately (due to
sk_buff overhead) and the receive buffer size may
be changed by user-space after flow credits have
been sent, superfluous received data is temporary
stored within l2cap_pinfo. This is necessary
because Bluetooth LE provides no retransmission
mechanism once the data has been acked by the
physical layer.

If receive buffer space estimation is not possible
at the moment, we fall back to providing credits
for one full packet as before. This is currently
the case during connection setup, when MPS is not
yet available.

Fixes: b1c325c23d75 ("Bluetooth: Implement returning of LE L2CAP credits")
Signed-off-by: Sebastian Urban <surban@surban.net>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Bluetooth: L2CAP: Fix div-by-zero in l2cap_le_flowctl_init() 2024-05-25T14:30:54+00:00 Sungwoo Kim iam@sung-woo.kim 2024-05-04T19:23:29+00:00 d2b2f7d3936dc5990549bc36ab7ac7ac37f22c30 commit a5b862c6a221459d54e494e88965b48dcfa6cc44 upstream. l2cap_le_flowctl_init() can cause both div-by-zero and an integer overflow since hdev->le_mtu may not fall in the valid range. Move MTU from hci_dev to hci_conn to validate MTU and stop the connection process earlier if MTU is invalid. Also, add a missing validation in read_buffer_size() and make it return an error value if the validation fails. Now hci_conn_add() returns ERR_PTR() as it can fail due to the both a kzalloc failure and invalid MTU value. divide error: 0000 [#1] PREEMPT SMP KASAN NOPTI CPU: 0 PID: 67 Comm: kworker/u5:0 Tainted: G W 6.9.0-rc5+ #20 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014 Workqueue: hci0 hci_rx_work RIP: 0010:l2cap_le_flowctl_init+0x19e/0x3f0 net/bluetooth/l2cap_core.c:547 Code: e8 17 17 0c 00 66 41 89 9f 84 00 00 00 bf 01 00 00 00 41 b8 02 00 00 00 4c 89 fe 4c 89 e2 89 d9 e8 27 17 0c 00 44 89 f0 31 d2 <66> f7 f3 89 c3 ff c3 4d 8d b7 88 00 00 00 4c 89 f0 48 c1 e8 03 42 RSP: 0018:ffff88810bc0f858 EFLAGS: 00010246 RAX: 00000000000002a0 RBX: 0000000000000000 RCX: dffffc0000000000 RDX: 0000000000000000 RSI: ffff88810bc0f7c0 RDI: ffffc90002dcb66f RBP: ffff88810bc0f880 R08: aa69db2dda70ff01 R09: 0000ffaaaaaaaaaa R10: 0084000000ffaaaa R11: 0000000000000000 R12: ffff88810d65a084 R13: dffffc0000000000 R14: 00000000000002a0 R15: ffff88810d65a000 FS: 0000000000000000(0000) GS:ffff88811ac00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020000100 CR3: 0000000103268003 CR4: 0000000000770ef0 PKRU: 55555554 Call Trace: <TASK> l2cap_le_connect_req net/bluetooth/l2cap_core.c:4902 [inline] l2cap_le_sig_cmd net/bluetooth/l2cap_core.c:5420 [inline] l2cap_le_sig_channel net/bluetooth/l2cap_core.c:5486 [inline] l2cap_recv_frame+0xe59d/0x11710 net/bluetooth/l2cap_core.c:6809 l2cap_recv_acldata+0x544/0x10a0 net/bluetooth/l2cap_core.c:7506 hci_acldata_packet net/bluetooth/hci_core.c:3939 [inline] hci_rx_work+0x5e5/0xb20 net/bluetooth/hci_core.c:4176 process_one_work kernel/workqueue.c:3254 [inline] process_scheduled_works+0x90f/0x1530 kernel/workqueue.c:3335 worker_thread+0x926/0xe70 kernel/workqueue.c:3416 kthread+0x2e3/0x380 kernel/kthread.c:388 ret_from_fork+0x5c/0x90 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 </TASK> Modules linked in: ---[ end trace 0000000000000000 ]--- Fixes: 6ed58ec520ad ("Bluetooth: Use LE buffers for LE traffic") Suggested-by: Luiz Augusto von Dentz <luiz.dentz@gmail.com> Signed-off-by: Sungwoo Kim <iam@sung-woo.kim> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit a5b862c6a221459d54e494e88965b48dcfa6cc44 upstream.

l2cap_le_flowctl_init() can cause both div-by-zero and an integer
overflow since hdev->le_mtu may not fall in the valid range.

Move MTU from hci_dev to hci_conn to validate MTU and stop the connection
process earlier if MTU is invalid.
Also, add a missing validation in read_buffer_size() and make it return
an error value if the validation fails.
Now hci_conn_add() returns ERR_PTR() as it can fail due to the both a
kzalloc failure and invalid MTU value.

divide error: 0000 [#1] PREEMPT SMP KASAN NOPTI
CPU: 0 PID: 67 Comm: kworker/u5:0 Tainted: G        W          6.9.0-rc5+ #20
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014
Workqueue: hci0 hci_rx_work
RIP: 0010:l2cap_le_flowctl_init+0x19e/0x3f0 net/bluetooth/l2cap_core.c:547
Code: e8 17 17 0c 00 66 41 89 9f 84 00 00 00 bf 01 00 00 00 41 b8 02 00 00 00 4c
89 fe 4c 89 e2 89 d9 e8 27 17 0c 00 44 89 f0 31 d2 <66> f7 f3 89 c3 ff c3 4d 8d
b7 88 00 00 00 4c 89 f0 48 c1 e8 03 42
RSP: 0018:ffff88810bc0f858 EFLAGS: 00010246
RAX: 00000000000002a0 RBX: 0000000000000000 RCX: dffffc0000000000
RDX: 0000000000000000 RSI: ffff88810bc0f7c0 RDI: ffffc90002dcb66f
RBP: ffff88810bc0f880 R08: aa69db2dda70ff01 R09: 0000ffaaaaaaaaaa
R10: 0084000000ffaaaa R11: 0000000000000000 R12: ffff88810d65a084
R13: dffffc0000000000 R14: 00000000000002a0 R15: ffff88810d65a000
FS:  0000000000000000(0000) GS:ffff88811ac00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020000100 CR3: 0000000103268003 CR4: 0000000000770ef0
PKRU: 55555554
Call Trace:
 <TASK>
 l2cap_le_connect_req net/bluetooth/l2cap_core.c:4902 [inline]
 l2cap_le_sig_cmd net/bluetooth/l2cap_core.c:5420 [inline]
 l2cap_le_sig_channel net/bluetooth/l2cap_core.c:5486 [inline]
 l2cap_recv_frame+0xe59d/0x11710 net/bluetooth/l2cap_core.c:6809
 l2cap_recv_acldata+0x544/0x10a0 net/bluetooth/l2cap_core.c:7506
 hci_acldata_packet net/bluetooth/hci_core.c:3939 [inline]
 hci_rx_work+0x5e5/0xb20 net/bluetooth/hci_core.c:4176
 process_one_work kernel/workqueue.c:3254 [inline]
 process_scheduled_works+0x90f/0x1530 kernel/workqueue.c:3335
 worker_thread+0x926/0xe70 kernel/workqueue.c:3416
 kthread+0x2e3/0x380 kernel/kthread.c:388
 ret_from_fork+0x5c/0x90 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---

Fixes: 6ed58ec520ad ("Bluetooth: Use LE buffers for LE traffic")
Suggested-by: Luiz Augusto von Dentz <luiz.dentz@gmail.com>
Signed-off-by: Sungwoo Kim <iam@sung-woo.kim>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Bluetooth: l2cap: fix null-ptr-deref in l2cap_chan_timeout 2024-05-03T17:05:54+00:00 Duoming Zhou duoming@zju.edu.cn 2024-05-02T12:57:36+00:00 adf0398cee86643b8eacde95f17d073d022f782c There is a race condition between l2cap_chan_timeout() and l2cap_chan_del(). When we use l2cap_chan_del() to delete the channel, the chan->conn will be set to null. But the conn could be dereferenced again in the mutex_lock() of l2cap_chan_timeout(). As a result the null pointer dereference bug will happen. The KASAN report triggered by POC is shown below: [ 472.074580] ================================================================== [ 472.075284] BUG: KASAN: null-ptr-deref in mutex_lock+0x68/0xc0 [ 472.075308] Write of size 8 at addr 0000000000000158 by task kworker/0:0/7 [ 472.075308] [ 472.075308] CPU: 0 PID: 7 Comm: kworker/0:0 Not tainted 6.9.0-rc5-00356-g78c0094a146b #36 [ 472.075308] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu4 [ 472.075308] Workqueue: events l2cap_chan_timeout [ 472.075308] Call Trace: [ 472.075308] <TASK> [ 472.075308] dump_stack_lvl+0x137/0x1a0 [ 472.075308] print_report+0x101/0x250 [ 472.075308] ? __virt_addr_valid+0x77/0x160 [ 472.075308] ? mutex_lock+0x68/0xc0 [ 472.075308] kasan_report+0x139/0x170 [ 472.075308] ? mutex_lock+0x68/0xc0 [ 472.075308] kasan_check_range+0x2c3/0x2e0 [ 472.075308] mutex_lock+0x68/0xc0 [ 472.075308] l2cap_chan_timeout+0x181/0x300 [ 472.075308] process_one_work+0x5d2/0xe00 [ 472.075308] worker_thread+0xe1d/0x1660 [ 472.075308] ? pr_cont_work+0x5e0/0x5e0 [ 472.075308] kthread+0x2b7/0x350 [ 472.075308] ? pr_cont_work+0x5e0/0x5e0 [ 472.075308] ? kthread_blkcg+0xd0/0xd0 [ 472.075308] ret_from_fork+0x4d/0x80 [ 472.075308] ? kthread_blkcg+0xd0/0xd0 [ 472.075308] ret_from_fork_asm+0x11/0x20 [ 472.075308] </TASK> [ 472.075308] ================================================================== [ 472.094860] Disabling lock debugging due to kernel taint [ 472.096136] BUG: kernel NULL pointer dereference, address: 0000000000000158 [ 472.096136] #PF: supervisor write access in kernel mode [ 472.096136] #PF: error_code(0x0002) - not-present page [ 472.096136] PGD 0 P4D 0 [ 472.096136] Oops: 0002 [#1] PREEMPT SMP KASAN NOPTI [ 472.096136] CPU: 0 PID: 7 Comm: kworker/0:0 Tainted: G B 6.9.0-rc5-00356-g78c0094a146b #36 [ 472.096136] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu4 [ 472.096136] Workqueue: events l2cap_chan_timeout [ 472.096136] RIP: 0010:mutex_lock+0x88/0xc0 [ 472.096136] Code: be 08 00 00 00 e8 f8 23 1f fd 4c 89 f7 be 08 00 00 00 e8 eb 23 1f fd 42 80 3c 23 00 74 08 48 88 [ 472.096136] RSP: 0018:ffff88800744fc78 EFLAGS: 00000246 [ 472.096136] RAX: 0000000000000000 RBX: 1ffff11000e89f8f RCX: ffffffff8457c865 [ 472.096136] RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffff88800744fc78 [ 472.096136] RBP: 0000000000000158 R08: ffff88800744fc7f R09: 1ffff11000e89f8f [ 472.096136] R10: dffffc0000000000 R11: ffffed1000e89f90 R12: dffffc0000000000 [ 472.096136] R13: 0000000000000158 R14: ffff88800744fc78 R15: ffff888007405a00 [ 472.096136] FS: 0000000000000000(0000) GS:ffff88806d200000(0000) knlGS:0000000000000000 [ 472.096136] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 472.096136] CR2: 0000000000000158 CR3: 000000000da32000 CR4: 00000000000006f0 [ 472.096136] Call Trace: [ 472.096136] <TASK> [ 472.096136] ? __die_body+0x8d/0xe0 [ 472.096136] ? page_fault_oops+0x6b8/0x9a0 [ 472.096136] ? kernelmode_fixup_or_oops+0x20c/0x2a0 [ 472.096136] ? do_user_addr_fault+0x1027/0x1340 [ 472.096136] ? _printk+0x7a/0xa0 [ 472.096136] ? mutex_lock+0x68/0xc0 [ 472.096136] ? add_taint+0x42/0xd0 [ 472.096136] ? exc_page_fault+0x6a/0x1b0 [ 472.096136] ? asm_exc_page_fault+0x26/0x30 [ 472.096136] ? mutex_lock+0x75/0xc0 [ 472.096136] ? mutex_lock+0x88/0xc0 [ 472.096136] ? mutex_lock+0x75/0xc0 [ 472.096136] l2cap_chan_timeout+0x181/0x300 [ 472.096136] process_one_work+0x5d2/0xe00 [ 472.096136] worker_thread+0xe1d/0x1660 [ 472.096136] ? pr_cont_work+0x5e0/0x5e0 [ 472.096136] kthread+0x2b7/0x350 [ 472.096136] ? pr_cont_work+0x5e0/0x5e0 [ 472.096136] ? kthread_blkcg+0xd0/0xd0 [ 472.096136] ret_from_fork+0x4d/0x80 [ 472.096136] ? kthread_blkcg+0xd0/0xd0 [ 472.096136] ret_from_fork_asm+0x11/0x20 [ 472.096136] </TASK> [ 472.096136] Modules linked in: [ 472.096136] CR2: 0000000000000158 [ 472.096136] ---[ end trace 0000000000000000 ]--- [ 472.096136] RIP: 0010:mutex_lock+0x88/0xc0 [ 472.096136] Code: be 08 00 00 00 e8 f8 23 1f fd 4c 89 f7 be 08 00 00 00 e8 eb 23 1f fd 42 80 3c 23 00 74 08 48 88 [ 472.096136] RSP: 0018:ffff88800744fc78 EFLAGS: 00000246 [ 472.096136] RAX: 0000000000000000 RBX: 1ffff11000e89f8f RCX: ffffffff8457c865 [ 472.096136] RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffff88800744fc78 [ 472.096136] RBP: 0000000000000158 R08: ffff88800744fc7f R09: 1ffff11000e89f8f [ 472.132932] R10: dffffc0000000000 R11: ffffed1000e89f90 R12: dffffc0000000000 [ 472.132932] R13: 0000000000000158 R14: ffff88800744fc78 R15: ffff888007405a00 [ 472.132932] FS: 0000000000000000(0000) GS:ffff88806d200000(0000) knlGS:0000000000000000 [ 472.132932] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 472.132932] CR2: 0000000000000158 CR3: 000000000da32000 CR4: 00000000000006f0 [ 472.132932] Kernel panic - not syncing: Fatal exception [ 472.132932] Kernel Offset: disabled [ 472.132932] ---[ end Kernel panic - not syncing: Fatal exception ]--- Add a check to judge whether the conn is null in l2cap_chan_timeout() in order to mitigate the bug. Fixes: 3df91ea20e74 ("Bluetooth: Revert to mutexes from RCU list") Signed-off-by: Duoming Zhou <duoming@zju.edu.cn> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> 
There is a race condition between l2cap_chan_timeout() and
l2cap_chan_del(). When we use l2cap_chan_del() to delete the
channel, the chan->conn will be set to null. But the conn could
be dereferenced again in the mutex_lock() of l2cap_chan_timeout().
As a result the null pointer dereference bug will happen. The
KASAN report triggered by POC is shown below:

[  472.074580] ==================================================================
[  472.075284] BUG: KASAN: null-ptr-deref in mutex_lock+0x68/0xc0
[  472.075308] Write of size 8 at addr 0000000000000158 by task kworker/0:0/7
[  472.075308]
[  472.075308] CPU: 0 PID: 7 Comm: kworker/0:0 Not tainted 6.9.0-rc5-00356-g78c0094a146b #36
[  472.075308] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu4
[  472.075308] Workqueue: events l2cap_chan_timeout
[  472.075308] Call Trace:
[  472.075308]  <TASK>
[  472.075308]  dump_stack_lvl+0x137/0x1a0
[  472.075308]  print_report+0x101/0x250
[  472.075308]  ? __virt_addr_valid+0x77/0x160
[  472.075308]  ? mutex_lock+0x68/0xc0
[  472.075308]  kasan_report+0x139/0x170
[  472.075308]  ? mutex_lock+0x68/0xc0
[  472.075308]  kasan_check_range+0x2c3/0x2e0
[  472.075308]  mutex_lock+0x68/0xc0
[  472.075308]  l2cap_chan_timeout+0x181/0x300
[  472.075308]  process_one_work+0x5d2/0xe00
[  472.075308]  worker_thread+0xe1d/0x1660
[  472.075308]  ? pr_cont_work+0x5e0/0x5e0
[  472.075308]  kthread+0x2b7/0x350
[  472.075308]  ? pr_cont_work+0x5e0/0x5e0
[  472.075308]  ? kthread_blkcg+0xd0/0xd0
[  472.075308]  ret_from_fork+0x4d/0x80
[  472.075308]  ? kthread_blkcg+0xd0/0xd0
[  472.075308]  ret_from_fork_asm+0x11/0x20
[  472.075308]  </TASK>
[  472.075308] ==================================================================
[  472.094860] Disabling lock debugging due to kernel taint
[  472.096136] BUG: kernel NULL pointer dereference, address: 0000000000000158
[  472.096136] #PF: supervisor write access in kernel mode
[  472.096136] #PF: error_code(0x0002) - not-present page
[  472.096136] PGD 0 P4D 0
[  472.096136] Oops: 0002 [#1] PREEMPT SMP KASAN NOPTI
[  472.096136] CPU: 0 PID: 7 Comm: kworker/0:0 Tainted: G    B              6.9.0-rc5-00356-g78c0094a146b #36
[  472.096136] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu4
[  472.096136] Workqueue: events l2cap_chan_timeout
[  472.096136] RIP: 0010:mutex_lock+0x88/0xc0
[  472.096136] Code: be 08 00 00 00 e8 f8 23 1f fd 4c 89 f7 be 08 00 00 00 e8 eb 23 1f fd 42 80 3c 23 00 74 08 48 88
[  472.096136] RSP: 0018:ffff88800744fc78 EFLAGS: 00000246
[  472.096136] RAX: 0000000000000000 RBX: 1ffff11000e89f8f RCX: ffffffff8457c865
[  472.096136] RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffff88800744fc78
[  472.096136] RBP: 0000000000000158 R08: ffff88800744fc7f R09: 1ffff11000e89f8f
[  472.096136] R10: dffffc0000000000 R11: ffffed1000e89f90 R12: dffffc0000000000
[  472.096136] R13: 0000000000000158 R14: ffff88800744fc78 R15: ffff888007405a00
[  472.096136] FS:  0000000000000000(0000) GS:ffff88806d200000(0000) knlGS:0000000000000000
[  472.096136] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  472.096136] CR2: 0000000000000158 CR3: 000000000da32000 CR4: 00000000000006f0
[  472.096136] Call Trace:
[  472.096136]  <TASK>
[  472.096136]  ? __die_body+0x8d/0xe0
[  472.096136]  ? page_fault_oops+0x6b8/0x9a0
[  472.096136]  ? kernelmode_fixup_or_oops+0x20c/0x2a0
[  472.096136]  ? do_user_addr_fault+0x1027/0x1340
[  472.096136]  ? _printk+0x7a/0xa0
[  472.096136]  ? mutex_lock+0x68/0xc0
[  472.096136]  ? add_taint+0x42/0xd0
[  472.096136]  ? exc_page_fault+0x6a/0x1b0
[  472.096136]  ? asm_exc_page_fault+0x26/0x30
[  472.096136]  ? mutex_lock+0x75/0xc0
[  472.096136]  ? mutex_lock+0x88/0xc0
[  472.096136]  ? mutex_lock+0x75/0xc0
[  472.096136]  l2cap_chan_timeout+0x181/0x300
[  472.096136]  process_one_work+0x5d2/0xe00
[  472.096136]  worker_thread+0xe1d/0x1660
[  472.096136]  ? pr_cont_work+0x5e0/0x5e0
[  472.096136]  kthread+0x2b7/0x350
[  472.096136]  ? pr_cont_work+0x5e0/0x5e0
[  472.096136]  ? kthread_blkcg+0xd0/0xd0
[  472.096136]  ret_from_fork+0x4d/0x80
[  472.096136]  ? kthread_blkcg+0xd0/0xd0
[  472.096136]  ret_from_fork_asm+0x11/0x20
[  472.096136]  </TASK>
[  472.096136] Modules linked in:
[  472.096136] CR2: 0000000000000158
[  472.096136] ---[ end trace 0000000000000000 ]---
[  472.096136] RIP: 0010:mutex_lock+0x88/0xc0
[  472.096136] Code: be 08 00 00 00 e8 f8 23 1f fd 4c 89 f7 be 08 00 00 00 e8 eb 23 1f fd 42 80 3c 23 00 74 08 48 88
[  472.096136] RSP: 0018:ffff88800744fc78 EFLAGS: 00000246
[  472.096136] RAX: 0000000000000000 RBX: 1ffff11000e89f8f RCX: ffffffff8457c865
[  472.096136] RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffff88800744fc78
[  472.096136] RBP: 0000000000000158 R08: ffff88800744fc7f R09: 1ffff11000e89f8f
[  472.132932] R10: dffffc0000000000 R11: ffffed1000e89f90 R12: dffffc0000000000
[  472.132932] R13: 0000000000000158 R14: ffff88800744fc78 R15: ffff888007405a00
[  472.132932] FS:  0000000000000000(0000) GS:ffff88806d200000(0000) knlGS:0000000000000000
[  472.132932] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  472.132932] CR2: 0000000000000158 CR3: 000000000da32000 CR4: 00000000000006f0
[  472.132932] Kernel panic - not syncing: Fatal exception
[  472.132932] Kernel Offset: disabled
[  472.132932] ---[ end Kernel panic - not syncing: Fatal exception ]---

Add a check to judge whether the conn is null in l2cap_chan_timeout()
in order to mitigate the bug.

Fixes: 3df91ea20e74 ("Bluetooth: Revert to mutexes from RCU list")
Signed-off-by: Duoming Zhou <duoming@zju.edu.cn>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Bluetooth: HCI: Fix potential null-ptr-deref 2024-05-03T17:05:53+00:00 Sungwoo Kim iam@sung-woo.kim 2024-05-02T16:09:31+00:00 d2706004a1b8b526592e823d7e52551b518a7941 Fix potential null-ptr-deref in hci_le_big_sync_established_evt(). Fixes: f777d8827817 (Bluetooth: ISO: Notify user space about failed bis connections) Signed-off-by: Sungwoo Kim <iam@sung-woo.kim> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> 
Fix potential null-ptr-deref in hci_le_big_sync_established_evt().

Fixes: f777d8827817 (Bluetooth: ISO: Notify user space about failed bis connections)
Signed-off-by: Sungwoo Kim <iam@sung-woo.kim>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Bluetooth: msft: fix slab-use-after-free in msft_do_close() 2024-05-03T17:05:28+00:00 Sungwoo Kim iam@sung-woo.kim 2024-04-30T16:20:51+00:00 10f9f426ac6e752c8d87bf4346930ba347aaabac Tying the msft->data lifetime to hdev by freeing it in hci_release_dev() to fix the following case: [use] msft_do_close() msft = hdev->msft_data; if (!msft) ...(1) <- passed. return; mutex_lock(&msft->filter_lock); ...(4) <- used after freed. [free] msft_unregister() msft = hdev->msft_data; hdev->msft_data = NULL; ...(2) kfree(msft); ...(3) <- msft is freed. ================================================================== BUG: KASAN: slab-use-after-free in __mutex_lock_common kernel/locking/mutex.c:587 [inline] BUG: KASAN: slab-use-after-free in __mutex_lock+0x8f/0xc30 kernel/locking/mutex.c:752 Read of size 8 at addr ffff888106cbbca8 by task kworker/u5:2/309 Fixes: bf6a4e30ffbd ("Bluetooth: disable advertisement filters during suspend") Signed-off-by: Sungwoo Kim <iam@sung-woo.kim> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> 
Tying the msft->data lifetime to hdev by freeing it in
hci_release_dev() to fix the following case:

[use]
msft_do_close()
  msft = hdev->msft_data;
  if (!msft)                      ...(1) <- passed.
    return;
  mutex_lock(&msft->filter_lock); ...(4) <- used after freed.

[free]
msft_unregister()
  msft = hdev->msft_data;
  hdev->msft_data = NULL;         ...(2)
  kfree(msft);                    ...(3) <- msft is freed.

==================================================================
BUG: KASAN: slab-use-after-free in __mutex_lock_common
kernel/locking/mutex.c:587 [inline]
BUG: KASAN: slab-use-after-free in __mutex_lock+0x8f/0xc30
kernel/locking/mutex.c:752
Read of size 8 at addr ffff888106cbbca8 by task kworker/u5:2/309

Fixes: bf6a4e30ffbd ("Bluetooth: disable advertisement filters during suspend")
Signed-off-by: Sungwoo Kim <iam@sung-woo.kim>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Bluetooth: L2CAP: Fix slab-use-after-free in l2cap_connect() 2024-05-03T17:05:26+00:00 Sungwoo Kim iam@sung-woo.kim 2024-04-30T06:32:10+00:00 4d7b41c0e43995b0e992b9f8903109275744b658 Extend a critical section to prevent chan from early freeing. Also make the l2cap_connect() return type void. Nothing is using the returned value but it is ugly to return a potentially freed pointer. Making it void will help with backports because earlier kernels did use the return value. Now the compile will break for kernels where this patch is not a complete fix. Call stack summary: [use] l2cap_bredr_sig_cmd l2cap_connect ┌ mutex_lock(&conn->chan_lock); │ chan = pchan->ops->new_connection(pchan); <- alloc chan │ __l2cap_chan_add(conn, chan); │ l2cap_chan_hold(chan); │ list_add(&chan->list, &conn->chan_l); ... (1) └ mutex_unlock(&conn->chan_lock); chan->conf_state ... (4) <- use after free [free] l2cap_conn_del ┌ mutex_lock(&conn->chan_lock); │ foreach chan in conn->chan_l: ... (2) │ l2cap_chan_put(chan); │ l2cap_chan_destroy │ kfree(chan) ... (3) <- chan freed └ mutex_unlock(&conn->chan_lock); ================================================================== BUG: KASAN: slab-use-after-free in instrument_atomic_read include/linux/instrumented.h:68 [inline] BUG: KASAN: slab-use-after-free in _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline] BUG: KASAN: slab-use-after-free in l2cap_connect+0xa67/0x11a0 net/bluetooth/l2cap_core.c:4260 Read of size 8 at addr ffff88810bf040a0 by task kworker/u3:1/311 Fixes: 73ffa904b782 ("Bluetooth: Move conf_{req,rsp} stuff to struct l2cap_chan") Signed-off-by: Sungwoo Kim <iam@sung-woo.kim> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> 
Extend a critical section to prevent chan from early freeing.
Also make the l2cap_connect() return type void. Nothing is using the
returned value but it is ugly to return a potentially freed pointer.
Making it void will help with backports because earlier kernels did use
the return value. Now the compile will break for kernels where this
patch is not a complete fix.

Call stack summary:

[use]
l2cap_bredr_sig_cmd
  l2cap_connect
  ┌ mutex_lock(&conn->chan_lock);
  │ chan = pchan->ops->new_connection(pchan); <- alloc chan
  │ __l2cap_chan_add(conn, chan);
  │   l2cap_chan_hold(chan);
  │   list_add(&chan->list, &conn->chan_l);   ... (1)
  └ mutex_unlock(&conn->chan_lock);
    chan->conf_state              ... (4) <- use after free

[free]
l2cap_conn_del
┌ mutex_lock(&conn->chan_lock);
│ foreach chan in conn->chan_l:            ... (2)
│   l2cap_chan_put(chan);
│     l2cap_chan_destroy
│       kfree(chan)               ... (3) <- chan freed
└ mutex_unlock(&conn->chan_lock);

==================================================================
BUG: KASAN: slab-use-after-free in instrument_atomic_read
include/linux/instrumented.h:68 [inline]
BUG: KASAN: slab-use-after-free in _test_bit
include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline]
BUG: KASAN: slab-use-after-free in l2cap_connect+0xa67/0x11a0
net/bluetooth/l2cap_core.c:4260
Read of size 8 at addr ffff88810bf040a0 by task kworker/u3:1/311

Fixes: 73ffa904b782 ("Bluetooth: Move conf_{req,rsp} stuff to struct l2cap_chan")
Signed-off-by: Sungwoo Kim <iam@sung-woo.kim>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>