When TX timestamping is enabled via SO_TIMESTAMPING, SKBs may be queued
into sk_error_queue and will stay there until consumed. If userspace never
gets to read the timestamps, or if the controller is removed unexpectedly,
these SKBs will leak.
Fix by adding skb_queue_purge() calls for sk_error_queue in affected
bluetooth destructors. RFCOMM does not currently use sk_error_queue.
Fixes: 134f4b39df ("Bluetooth: add support for skb TX SND/COMPLETION timestamping")
Reported-by: syzbot+7ff4013eabad1407b70a@syzkaller.appspotmail.com
Closes: https://syzbot.org/bug?extid=7ff4013eabad1407b70a
Cc: stable@vger.kernel.org
Signed-off-by: Heitor Alves de Siqueira <halves@igalia.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
This was done entirely with mindless brute force, using
git grep -l '\<k[vmz]*alloc_objs*(.*, GFP_KERNEL)' |
xargs sed -i 's/\(alloc_objs*(.*\), GFP_KERNEL)/\1)/'
to convert the new alloc_obj() users that had a simple GFP_KERNEL
argument to just drop that argument.
Note that due to the extreme simplicity of the scripting, any slightly
more complex cases spread over multiple lines would not be triggered:
they definitely exist, but this covers the vast bulk of the cases, and
the resulting diff is also then easier to check automatically.
For the same reason the 'flex' versions will be done as a separate
conversion.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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 <kees@kernel.org>
The hdev lock/lookup/unlock/use pattern in the packet RX path doesn't
ensure hci_conn* is not concurrently modified/deleted. This locking
appears to be leftover from before conn_hash started using RCU
commit bf4c632524 ("Bluetooth: convert conn hash to RCU")
and not clear if it had purpose since then.
Currently, there are code paths that delete hci_conn* from elsewhere
than the ordered hdev->workqueue where the RX work runs in. E.g.
commit 5af1f84ed1 ("Bluetooth: hci_sync: Fix UAF on hci_abort_conn_sync")
introduced some of these, and there probably were a few others before
it. It's better to do the locking so that even if these run
concurrently no UAF is possible.
Move the lookup of hci_conn and associated socket-specific conn to
protocol recv handlers, and do them within a single critical section
to cover hci_conn* usage and lookup.
syzkaller has reported a crash that appears to be this issue:
[Task hdev->workqueue] [Task 2]
hci_disconnect_all_sync
l2cap_recv_acldata(hcon)
hci_conn_get(hcon)
hci_abort_conn_sync(hcon)
hci_dev_lock
hci_dev_lock
hci_conn_del(hcon)
v-------------------------------- hci_dev_unlock
hci_conn_put(hcon)
conn = hcon->l2cap_data (UAF)
Fixes: 5af1f84ed1 ("Bluetooth: hci_sync: Fix UAF on hci_abort_conn_sync")
Reported-by: syzbot+d32d77220b92eddd89ad@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=d32d77220b92eddd89ad
Signed-off-by: Pauli Virtanen <pav@iki.fi>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Update all struct proto_ops connect() callback function prototypes from
"struct sockaddr *" to "struct sockaddr_unsized *" to avoid lying to the
compiler about object sizes. Calls into struct proto handlers gain casts
that will be removed in the struct proto conversion patch.
No binary changes expected.
Signed-off-by: Kees Cook <kees@kernel.org>
Link: https://patch.msgid.link/20251104002617.2752303-3-kees@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Update all struct proto_ops bind() callback function prototypes from
"struct sockaddr *" to "struct sockaddr_unsized *" to avoid lying to the
compiler about object sizes. Calls into struct proto handlers gain casts
that will be removed in the struct proto conversion patch.
No binary changes expected.
Signed-off-by: Kees Cook <kees@kernel.org>
Link: https://patch.msgid.link/20251104002617.2752303-2-kees@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Followup of commit 285975dd67 ("net: annotate data-races around
sk->sk_{rcv|snd}timeo").
Remove lock_sock()/release_sock() from sock_set_sndtimeo(),
and add READ_ONCE()/WRITE_ONCE() where it is needed.
Also SO_SNDTIMEO_OLD and SO_SNDTIMEO_NEW can call sock_set_timeout()
without holding the socket lock.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20250620155536.335520-2-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Support TX timestamping in SCO sockets.
Not available for hdevs without SCO_FLOWCTL.
Support MSG_ERRQUEUE in SCO recvmsg.
Signed-off-by: Pauli Virtanen <pav@iki.fi>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
This reverts commit 4d94f05558 which has
problems (see [1]) and is no longer needed since 581dd2dc16
("Bluetooth: hci_event: Fix using rcu_read_(un)lock while iterating")
has reworked the code where the original bug has been found.
[1] Link: https://lore.kernel.org/linux-bluetooth/877c55ci1r.wl-tiwai@suse.de/T/#t
Fixes: 4d94f05558 ("Bluetooth: hci_core: Fix sleeping function called from invalid context")
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
sco_conn refcount shall not be incremented a second time if the sk
already owns the refcount, so hold only when adding new chan.
Add sco_conn_hold() for clarity, as refcnt is never zero here due to the
sco_conn_add().
Fixes SCO socket shutdown not actually closing the SCO connection.
Fixes: ed95885549 ("Bluetooth: SCO: remove the redundant sco_conn_put")
Signed-off-by: Pauli Virtanen <pav@iki.fi>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
The voice setting is used by sco_connect() or sco_conn_defer_accept()
after being set by sco_sock_setsockopt().
The PCM part of the voice setting is used for offload mode through PCM
chipset port.
This commits add support for mSBC 16 bits offloading, i.e. audio data
not transported over HCI.
The BCM4349B1 supports 16 bits transparent data on its I2S port.
If BT_VOICE_TRANSPARENT is used when accepting a SCO connection, this
gives only garbage audio while using BT_VOICE_TRANSPARENT_16BIT gives
correct audio.
This has been tested with connection to iPhone 14 and Samsung S24.
Fixes: ad10b1a487 ("Bluetooth: Add Bluetooth socket voice option")
Signed-off-by: Frédéric Danis <frederic.danis@collabora.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
The bt_copy_from_sockptr() return value is being misinterpreted by most
users: a non-zero result is mistakenly assumed to represent an error code,
but actually indicates the number of bytes that could not be copied.
Remove bt_copy_from_sockptr() and adapt callers to use
copy_safe_from_sockptr().
For sco_sock_setsockopt() (case BT_CODEC) use copy_struct_from_sockptr() to
scrub parts of uninitialized buffer.
Opportunistically, rename `len` to `optlen` in hci_sock_setsockopt_old()
and hci_sock_setsockopt().
Fixes: 51eda36d33 ("Bluetooth: SCO: Fix not validating setsockopt user input")
Fixes: a97de7bff1 ("Bluetooth: RFCOMM: Fix not validating setsockopt user input")
Fixes: 4f3951242a ("Bluetooth: L2CAP: Fix not validating setsockopt user input")
Fixes: 9e8742cdfc ("Bluetooth: ISO: Fix not validating setsockopt user input")
Fixes: b2186061d6 ("Bluetooth: hci_sock: Fix not validating setsockopt user input")
Reviewed-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Reviewed-by: David Wei <dw@davidwei.uk>
Signed-off-by: Michal Luczaj <mhal@rbox.co>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
When adding conn, it is necessary to increase and retain the conn reference
count at the same time.
Another problem was fixed along the way, conn_put is missing when hcon is NULL
in the timeout routine.
Fixes: e6720779ae ("Bluetooth: SCO: Use kref to track lifetime of sco_conn")
Reported-and-tested-by: syzbot+489f78df4709ac2bfdd3@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=489f78df4709ac2bfdd3
Signed-off-by: Edward Adam Davis <eadavis@qq.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
This make use of kref to keep track of reference of sco_conn which
allows better tracking of its lifetime with usage of things like
kref_get_unless_zero in a similar way as used in l2cap_chan.
In addition to it remove call to sco_sock_set_timer on __sco_sock_close
since at that point it is useless to set a timer as the sk will be freed
there is nothing to be done in sco_sock_timeout.
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
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Merge tag 'net-accept-more-20240515' of git://git.kernel.dk/linux
Pull more io_uring updates from Jens Axboe:
"This adds support for IORING_CQE_F_SOCK_NONEMPTY for io_uring accept
requests.
This is very similar to previous work that enabled the same hint for
doing receives on sockets. By far the majority of the work here is
refactoring to enable the networking side to pass back whether or not
the socket had more pending requests after accepting the current one,
the last patch just wires it up for io_uring.
Not only does this enable applications to know whether there are more
connections to accept right now, it also enables smarter logic for
io_uring multishot accept on whether to retry immediately or wait for
a poll trigger"
* tag 'net-accept-more-20240515' of git://git.kernel.dk/linux:
io_uring/net: wire up IORING_CQE_F_SOCK_NONEMPTY for accept
net: pass back whether socket was empty post accept
net: have do_accept() take a struct proto_accept_arg argument
net: change proto and proto_ops accept type
Rather than pass in flags, error pointer, and whether this is a kernel
invocation or not, add a struct proto_accept_arg struct as the argument.
This then holds all of these arguments, and prepares accept for being
able to pass back more information.
No functional changes in this patch.
Acked-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
After an innocuous optimization change in LLVM main (19.0.0), x86_64
allmodconfig (which enables CONFIG_KCSAN / -fsanitize=thread) fails to
build due to the checks in check_copy_size():
In file included from net/bluetooth/sco.c:27:
In file included from include/linux/module.h:13:
In file included from include/linux/stat.h:19:
In file included from include/linux/time.h:60:
In file included from include/linux/time32.h:13:
In file included from include/linux/timex.h:67:
In file included from arch/x86/include/asm/timex.h:6:
In file included from arch/x86/include/asm/tsc.h:10:
In file included from arch/x86/include/asm/msr.h:15:
In file included from include/linux/percpu.h:7:
In file included from include/linux/smp.h:118:
include/linux/thread_info.h:244:4: error: call to '__bad_copy_from'
declared with 'error' attribute: copy source size is too small
244 | __bad_copy_from();
| ^
The same exact error occurs in l2cap_sock.c. The copy_to_user()
statements that are failing come from l2cap_sock_getsockopt_old() and
sco_sock_getsockopt_old(). This does not occur with GCC with or without
KCSAN or Clang without KCSAN enabled.
len is defined as an 'int' because it is assigned from
'__user int *optlen'. However, it is clamped against the result of
sizeof(), which has a type of 'size_t' ('unsigned long' for 64-bit
platforms). This is done with min_t() because min() requires compatible
types, which results in both len and the result of sizeof() being casted
to 'unsigned int', meaning len changes signs and the result of sizeof()
is truncated. From there, len is passed to copy_to_user(), which has a
third parameter type of 'unsigned long', so it is widened and changes
signs again. This excessive casting in combination with the KCSAN
instrumentation causes LLVM to fail to eliminate the __bad_copy_from()
call, failing the build.
The official recommendation from LLVM developers is to consistently use
long types for all size variables to avoid the unnecessary casting in
the first place. Change the type of len to size_t in both
l2cap_sock_getsockopt_old() and sco_sock_getsockopt_old(). This clears
up the error while allowing min_t() to be replaced with min(), resulting
in simpler code with no casts and fewer implicit conversions. While len
is a different type than optlen now, it should result in no functional
change because the result of sizeof() will clamp all values of optlen in
the same manner as before.
Cc: stable@vger.kernel.org
Closes: https://github.com/ClangBuiltLinux/linux/issues/2007
Link: https://github.com/llvm/llvm-project/issues/85647
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Justin Stitt <justinstitt@google.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
syzbot reported sco_sock_setsockopt() is copying data without
checking user input length.
BUG: KASAN: slab-out-of-bounds in copy_from_sockptr_offset
include/linux/sockptr.h:49 [inline]
BUG: KASAN: slab-out-of-bounds in copy_from_sockptr
include/linux/sockptr.h:55 [inline]
BUG: KASAN: slab-out-of-bounds in sco_sock_setsockopt+0xc0b/0xf90
net/bluetooth/sco.c:893
Read of size 4 at addr ffff88805f7b15a3 by task syz-executor.5/12578
Fixes: ad10b1a487 ("Bluetooth: Add Bluetooth socket voice option")
Fixes: b96e9c671b ("Bluetooth: Add BT_DEFER_SETUP option to sco socket")
Fixes: 00398e1d51 ("Bluetooth: Add support for BT_PKT_STATUS CMSG data for SCO connections")
Fixes: f6873401a6 ("Bluetooth: Allow setting of codec for HFP offload use case")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
This aligns the use socket sk_timeo as conn_timeout when initiating a
connection and then use it when scheduling the resulting HCI command,
that way the command is actually aborted synchronously thus not
blocking commands generated by hci_abort_conn_sync to inform the
controller the connection is to be aborted.
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
sk_getsockopt() runs locklessly. This means sk->sk_lingertime
can be read while other threads are changing its value.
Other reads also happen without socket lock being held,
and must be annotated.
Remove preprocessor logic using BITS_PER_LONG, compilers
are smart enough to figure this by themselves.
v2: fixed a clang W=1 (-Wtautological-constant-out-of-range-compare) warning
(Jakub)
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This makes the handling of BT_PKT_STATUS more generic so it can be
reused by sockets other than SCO like BT_DEFER_SETUP, etc.
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
This consolidates code around sk_alloc into bt_sock_alloc which does
take care of common initialization.
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Operations that check/update sk_state and access conn should hold
lock_sock, otherwise they can race.
The order of taking locks is hci_dev_lock > lock_sock > sco_conn_lock,
which is how it is in connect/disconnect_cfm -> sco_conn_del ->
sco_chan_del.
Fix locking in sco_connect to take lock_sock around updating sk_state
and conn.
sco_conn_del must not occur during sco_connect, as it frees the
sco_conn. Hold hdev->lock longer to prevent that.
sco_conn_add shall return sco_conn with valid hcon. Make it so also when
reusing an old SCO connection waiting for disconnect timeout (see
__sco_sock_close where conn->hcon is set to NULL).
This should not reintroduce the issue fixed in the earlier
commit 9a8ec9e8eb ("Bluetooth: SCO: Fix possible circular locking
dependency on sco_connect_cfm"), the relevant fix of releasing lock_sock
in sco_sock_connect before acquiring hdev->lock is retained.
These changes mirror similar fixes earlier in ISO sockets.
Fixes: 9a8ec9e8eb ("Bluetooth: SCO: Fix possible circular locking dependency on sco_connect_cfm")
Signed-off-by: Pauli Virtanen <pav@iki.fi>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
This adds HCI_QUIRK_BROKEN_ENHANCED_SETUP_SYNC_CONN quirk which can be
used to mark HCI_Enhanced_Setup_Synchronous_Connection as broken even
if its support command bit are set since some controller report it as
supported but the command don't work properly with some configurations
(e.g. BT_VOICE_TRANSPARENT/mSBC).
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Connecting the same socket twice consecutively in sco_sock_connect()
could lead to a race condition where two sco_conn objects are created
but only one is associated with the socket. If the socket is closed
before the SCO connection is established, the timer associated with the
dangling sco_conn object won't be canceled. As the sock object is being
freed, the use-after-free problem happens when the timer callback
function sco_sock_timeout() accesses the socket. Here's the call trace:
dump_stack+0x107/0x163
? refcount_inc+0x1c/
print_address_description.constprop.0+0x1c/0x47e
? refcount_inc+0x1c/0x7b
kasan_report+0x13a/0x173
? refcount_inc+0x1c/0x7b
check_memory_region+0x132/0x139
refcount_inc+0x1c/0x7b
sco_sock_timeout+0xb2/0x1ba
process_one_work+0x739/0xbd1
? cancel_delayed_work+0x13f/0x13f
? __raw_spin_lock_init+0xf0/0xf0
? to_kthread+0x59/0x85
worker_thread+0x593/0x70e
kthread+0x346/0x35a
? drain_workqueue+0x31a/0x31a
? kthread_bind+0x4b/0x4b
ret_from_fork+0x1f/0x30
Link: https://syzkaller.appspot.com/bug?extid=2bef95d3ab4daa10155b
Reported-by: syzbot+2bef95d3ab4daa10155b@syzkaller.appspotmail.com
Fixes: e1dee2c1de ("Bluetooth: fix repeated calls to sco_sock_kill")
Signed-off-by: Ying Hsu <yinghsu@chromium.org>
Reviewed-by: Joseph Hwang <josephsih@chromium.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The skb in modified by hci_send_sco which pushes SCO headers thus
changing skb->len causing sco_sock_sendmsg to fail.
Fixes: 0771cbb3b9 ("Bluetooth: SCO: Replace use of memcpy_from_msg with bt_skb_sendmsg")
Tested-by: Tedd Ho-Jeong An <tedd.an@intel.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Passing NULL to PTR_ERR will result in 0 (success), also since the likes of
bt_skb_sendmsg does never return NULL it is safe to replace the instances of
IS_ERR_OR_NULL with IS_ERR when checking its return.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Tested-by: Tedd Ho-Jeong An <tedd.an@intel.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
This makes use of bt_skb_sendmsg instead of allocating a different
buffer to be used with memcpy_from_msg which cause one extra copy.
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
This patch allows user space to set the codec that needs to
be used for HFP offload use case. The codec details are cached and
the controller is configured before opening the SCO connection.
Signed-off-by: Kiran K <kiran.k@intel.com>
Reviewed-by: Chethan T N <chethan.tumkur.narayan@intel.com>
Reviewed-by: Srivatsa Ravishankar <ravishankar.srivatsa@intel.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Add BT_CODEC option for getsockopt systemcall to get the details
of offload codecs supported over SCO socket
Signed-off-by: Kiran K <kiran.k@intel.com>
Reviewed-by: Chethan T N <chethan.tumkur.narayan@intel.com>
Reviewed-by: Srivatsa Ravishankar <ravishankar.srivatsa@intel.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Before freeing struct sco_conn, all delayed timeout work should be
cancelled. Otherwise, sco_sock_timeout could potentially use the
sco_conn after it has been freed.
Additionally, sco_conn.timeout_work should be initialized when the
connection is allocated, not when the channel is added. This is
because an sco_conn can create channels with multiple sockets over its
lifetime, which happens if sockets are released but the connection
isn't deleted.
Fixes: ba316be1b6 ("Bluetooth: schedule SCO timeouts with delayed_work")
Signed-off-by: Desmond Cheong Zhi Xi <desmondcheongzx@gmail.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
In sco_conn_del, conn->sk is read while holding on to the
sco_conn.lock to avoid races with a socket that could be released
concurrently.
However, in between unlocking sco_conn.lock and calling sock_hold,
it's possible for the socket to be freed, which would cause a
use-after-free write when sock_hold is finally called.
To fix this, the reference count of the socket should be increased
while the sco_conn.lock is still held.
Signed-off-by: Desmond Cheong Zhi Xi <desmondcheongzx@gmail.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
The sco_send_frame() also takes lock_sock() during memcpy_from_msg()
call that may be endlessly blocked by a task with userfaultd
technique, and this will result in a hung task watchdog trigger.
Just like the similar fix for hci_sock_sendmsg() in commit
92c685dc5de0 ("Bluetooth: reorganize functions..."), this patch moves
the memcpy_from_msg() out of lock_sock() for addressing the hang.
This should be the last piece for fixing CVE-2021-3640 after a few
already queued fixes.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
In commit 4e1a720d03 ("Bluetooth: avoid killing an already killed
socket"), a check was added to sco_sock_kill to skip killing a socket
if the SOCK_DEAD flag was set.
This was done after a trace for a use-after-free bug showed that the
same sock pointer was being killed twice.
Unfortunately, this check prevents sco_sock_kill from running on any
socket. sco_sock_kill kills a socket only if it's zapped and orphaned,
however sock_orphan announces that the socket is dead before detaching
it. i.e., orphaned sockets have the SOCK_DEAD flag set.
To fix this, we remove the check for SOCK_DEAD, and avoid repeated
calls to sco_sock_kill by removing incorrect calls in:
1. sco_sock_timeout. The socket should not be killed on timeout as
further processing is expected to be done. For example,
sco_sock_connect sets the timer then waits for the socket to be
connected or for an error to be returned.
2. sco_conn_del. This function should clean up resources for the
connection, but the socket itself should be cleaned up in
sco_sock_release.
3. sco_sock_close. Calls to sco_sock_close in sco_sock_cleanup_listen
and sco_sock_release are followed by sco_sock_kill. Hence the
duplicated call should be removed.
Fixes: 4e1a720d03 ("Bluetooth: avoid killing an already killed socket")
Signed-off-by: Desmond Cheong Zhi Xi <desmondcheongzx@gmail.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Currently, calls to sco_sock_set_timer are made under the locked
socket, but this does not apply to all calls to sco_sock_clear_timer.
Both sco_sock_{set,clear}_timer should be serialized by lock_sock to
prevent unexpected concurrent clearing/setting of timers.
Additionally, since sco_pi(sk)->conn is only cleared under the locked
socket, this change allows us to avoid races between
sco_sock_clear_timer and the call to kfree(conn) in sco_conn_del.
Signed-off-by: Desmond Cheong Zhi Xi <desmondcheongzx@gmail.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Since sco_sock_timeout is now scheduled using delayed work, it is no
longer run in SOFTIRQ context. Hence bh_lock_sock is no longer
necessary in SCO to synchronise between user contexts and SOFTIRQ
processing.
As such, calls to bh_lock_sock should be replaced with lock_sock to
synchronize with other concurrent processes that use lock_sock.
Signed-off-by: Desmond Cheong Zhi Xi <desmondcheongzx@gmail.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
struct sock.sk_timer should be used as a sock cleanup timer. However,
SCO uses it to implement sock timeouts.
This causes issues because struct sock.sk_timer's callback is run in
an IRQ context, and the timer callback function sco_sock_timeout takes
a spin lock on the socket. However, other functions such as
sco_conn_del and sco_conn_ready take the spin lock with interrupts
enabled.
This inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} lock usage could
lead to deadlocks as reported by Syzbot [1]:
CPU0
----
lock(slock-AF_BLUETOOTH-BTPROTO_SCO);
<Interrupt>
lock(slock-AF_BLUETOOTH-BTPROTO_SCO);
To fix this, we use delayed work to implement SCO sock timouts
instead. This allows us to avoid taking the spin lock on the socket in
an IRQ context, and corrects the misuse of struct sock.sk_timer.
As a note, cancel_delayed_work is used instead of
cancel_delayed_work_sync in sco_sock_set_timer and
sco_sock_clear_timer to avoid a deadlock. In the future, the call to
bh_lock_sock inside sco_sock_timeout should be changed to lock_sock to
synchronize with other functions using lock_sock. However, since
sco_sock_set_timer and sco_sock_clear_timer are sometimes called under
the locked socket (in sco_connect and __sco_sock_close),
cancel_delayed_work_sync might cause them to sleep until an
sco_sock_timeout that has started finishes running. But
sco_sock_timeout would also sleep until it can grab the lock_sock.
Using cancel_delayed_work is fine because sco_sock_timeout does not
change from run to run, hence there is no functional difference
between:
1. waiting for a timeout to finish running before scheduling another
timeout
2. scheduling another timeout while a timeout is running.
Link: https://syzkaller.appspot.com/bug?id=9089d89de0502e120f234ca0fc8a703f7368b31e [1]
Reported-by: syzbot+2f6d7c28bb4bf7e82060@syzkaller.appspotmail.com
Tested-by: syzbot+2f6d7c28bb4bf7e82060@syzkaller.appspotmail.com
Signed-off-by: Desmond Cheong Zhi Xi <desmondcheongzx@gmail.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Smatch complains that some of these struct members are not initialized
leading to a stack information disclosure:
net/bluetooth/sco.c:778 sco_conn_defer_accept() warn:
check that 'cp.retrans_effort' doesn't leak information
This seems like a valid warning. I've added a default case to fix
this issue.
Fixes: 2f69a82acf ("Bluetooth: Use voice setting in deferred SCO connection request")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
According to Documentation/core-api/printk-formats.rst,
Use the correct print format. Printing an unsigned int value should use %u
instead of %d. Otherwise printk() might end up displaying negative numbers.
Signed-off-by: Kai Ye <yekai13@huawei.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
