[syzbot] [bluetooth?] BUG: sleeping function called from invalid context in __hci_cmd_sync_sk

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 1f6ce8392d6f Add linux-next specific files for 20230613
git tree: linux-next
console+strace: https://syzkaller.appspot.com/x/log.txt?x=14adff43280000
kernel config: https://syzkaller.appspot.com/x/.config?x=d103d5f9125e9fe9
dashboard link: https://syzkaller.appspot.com/bug?extid=c715e1bd8dfbcb1ab176
compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=11287563280000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=14395963280000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/2d9bf45aeae9/disk-1f6ce839.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/e0b03ef83e17/vmlinux-1f6ce839.xz
kernel image: https://storage.googleapis.com/syzbot-assets/b6c21a24174d/bzImage-1f6ce839.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+c715e1...@syzkaller.appspotmail.com

BUG: sleeping function called from invalid context at net/bluetooth/hci_sync.c:166
in_atomic(): 0, irqs_disabled(): 0, non_block: 0, pid: 4430, name: kworker/u5:1
preempt_count: 0, expected: 0
RCU nest depth: 1, expected: 0
4 locks held by kworker/u5:1/4430:
#0: ffff888020183138 ((wq_completion)hci0#2){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:20 [inline]
#0: ffff888020183138 ((wq_completion)hci0#2){+.+.}-{0:0}, at: raw_atomic64_set include/linux/atomic/atomic-arch-fallback.h:2608 [inline]
#0: ffff888020183138 ((wq_completion)hci0#2){+.+.}-{0:0}, at: raw_atomic_long_set include/linux/atomic/atomic-long.h:79 [inline]
#0: ffff888020183138 ((wq_completion)hci0#2){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:3196 [inline]
#0: ffff888020183138 ((wq_completion)hci0#2){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:675 [inline]
#0: ffff888020183138 ((wq_completion)hci0#2){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:702 [inline]
#0: ffff888020183138 ((wq_completion)hci0#2){+.+.}-{0:0}, at: process_one_work+0x8fd/0x16f0 kernel/workqueue.c:2564
#1: ffffc900057a7db0 ((work_completion)(&hdev->rx_work)){+.+.}-{0:0}, at: process_one_work+0x930/0x16f0 kernel/workqueue.c:2568
#2: ffff88802b78c078 (&hdev->lock){+.+.}-{3:3}, at: hci_le_create_big_complete_evt+0xe9/0xab0 net/bluetooth/hci_event.c:6947
#3: ffffffff8c9a2840 (rcu_read_lock){....}-{1:2}, at: hci_le_ev_skb_pull net/bluetooth/hci_event.c:79 [inline]
#3: ffffffff8c9a2840 (rcu_read_lock){....}-{1:2}, at: hci_le_create_big_complete_evt+0xcc/0xab0 net/bluetooth/hci_event.c:6943
CPU: 0 PID: 4430 Comm: kworker/u5:1 Not tainted 6.4.0-rc6-next-20230613-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/25/2023
Workqueue: hci0 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x136/0x150 lib/dump_stack.c:106
__might_resched+0x358/0x580 kernel/sched/core.c:10188
__hci_cmd_sync_sk+0x359/0xe30 net/bluetooth/hci_sync.c:166
__hci_cmd_sync_status_sk+0x45/0x160 net/bluetooth/hci_sync.c:247
__hci_cmd_sync_status net/bluetooth/hci_sync.c:273 [inline]
hci_le_terminate_big_sync+0xa4/0xd0 net/bluetooth/hci_sync.c:1671
hci_le_create_big_complete_evt+0x741/0xab0 net/bluetooth/hci_event.c:6982
hci_le_meta_evt+0x2bc/0x510 net/bluetooth/hci_event.c:7182
hci_event_func net/bluetooth/hci_event.c:7512 [inline]
hci_event_packet+0x641/0xfd0 net/bluetooth/hci_event.c:7567
hci_rx_work+0xaeb/0x1340 net/bluetooth/hci_core.c:4064
process_one_work+0xa34/0x16f0 kernel/workqueue.c:2594
worker_thread+0x67d/0x10c0 kernel/workqueue.c:2745
kthread+0x344/0x440 kernel/kthread.c:379
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308
</TASK>
------------[ cut here ]------------
Voluntary context switch within RCU read-side critical section!
WARNING: CPU: 0 PID: 4430 at kernel/rcu/tree_plugin.h:320 rcu_note_context_switch+0xbb9/0x1800 kernel/rcu/tree_plugin.h:320
Modules linked in:
CPU: 0 PID: 4430 Comm: kworker/u5:1 Tainted: G W 6.4.0-rc6-next-20230613-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/25/2023
Workqueue: hci0 hci_rx_work
RIP: 0010:rcu_note_context_switch+0xbb9/0x1800 kernel/rcu/tree_plugin.h:320
Code: 1d 44 68 00 4c 8b 4c 24 30 8b 4c 24 28 48 8b 54 24 20 e9 8f 03 00 00 48 c7 c7 c0 32 6e 8a c6 05 10 41 24 0d 01 e8 87 83 dc ff <0f> 0b e9 4c f5 ff ff 81 e5 ff ff ff 7f 0f 84 d7 f6 ff ff 65 48 8b
RSP: 0018:ffffc900057a74c0 EFLAGS: 00010086
RAX: 0000000000000000 RBX: ffff8880b983d340 RCX: 0000000000000000
RDX: ffff88802c40bb80 RSI: ffffffff814bf5f7 RDI: 0000000000000001
RBP: ffff88802c40bb80 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000000
R13: ffff88802c40bb80 R14: ffffffff8ea9aff0 R15: ffff8880b983c440
FS: 0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f802b262fc8 CR3: 000000002812e000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
__schedule+0x276/0x5790 kernel/sched/core.c:6609
schedule+0xde/0x1a0 kernel/sched/core.c:6785
schedule_timeout+0x14e/0x2b0 kernel/time/timer.c:2167
__hci_cmd_sync_sk+0xc1d/0xe30 net/bluetooth/hci_sync.c:166
__hci_cmd_sync_status_sk+0x45/0x160 net/bluetooth/hci_sync.c:247
__hci_cmd_sync_status net/bluetooth/hci_sync.c:273 [inline]
hci_le_terminate_big_sync+0xa4/0xd0 net/bluetooth/hci_sync.c:1671
hci_le_create_big_complete_evt+0x741/0xab0 net/bluetooth/hci_event.c:6982
hci_le_meta_evt+0x2bc/0x510 net/bluetooth/hci_event.c:7182
hci_event_func net/bluetooth/hci_event.c:7512 [inline]
hci_event_packet+0x641/0xfd0 net/bluetooth/hci_event.c:7567
hci_rx_work+0xaeb/0x1340 net/bluetooth/hci_core.c:4064
process_one_work+0xa34/0x16f0 kernel/workqueue.c:2594
worker_thread+0x67d/0x10c0 kernel/workqueue.c:2745
kthread+0x344/0x440 kernel/kthread.c:379
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308
</TASK>


---
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[Hillf Danton]

On Sat, 17 Jun 2023 04:12:47 -0700

> syzbot found the following issue on:
>
> HEAD commit: 1f6ce8392d6f Add linux-next specific files for 20230613
> git tree: linux-next

> C reproducer: https://syzkaller.appspot.com/x/repro.c?x=14395963280000

Sync hci without rcu locked.

#syz test https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git 1f6ce8392d6f

--- x/net/bluetooth/hci_event.c
+++ y/net/bluetooth/hci_event.c
@@ -6973,6 +6973,7 @@ static void hci_le_create_big_complete_e
rcu_read_lock();
}

+ rcu_read_unlock();
if (!ev->status && !bis_idx)
/* If no BISes have been connected for the BIG,
* terminate. This is in case all bound connections
@@ -6981,8 +6982,6 @@ static void hci_le_create_big_complete_e
*/
hci_le_terminate_big_sync(hdev, ev->handle,
HCI_ERROR_LOCAL_HOST_TERM);
-
- rcu_read_unlock();
hci_dev_unlock(hdev);
}

--

[syzbot]

Hello,

syzbot has tested the proposed patch and the reproducer did not trigger any issue:

Reported-and-tested-by: syzbot+c715e1...@syzkaller.appspotmail.com

Tested on:

commit: 1f6ce839 Add linux-next specific files for 20230613
git tree: https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git
console output: https://syzkaller.appspot.com/x/log.txt?x=13bc9373280000

kernel config: https://syzkaller.appspot.com/x/.config?x=d103d5f9125e9fe9
dashboard link: https://syzkaller.appspot.com/bug?extid=c715e1bd8dfbcb1ab176
compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2

patch: https://syzkaller.appspot.com/x/patch.diff?x=14e6e45b280000

Note: testing is done by a robot and is best-effort only.

[syzbot]

syzbot has bisected this issue to:

commit 2e846cd83f6285f4fee49389954b1b1215f5e504
Author: Iulia Tanasescu <iulia.t...@nxp.com>
Date: Tue May 30 14:21:59 2023 +0000

Bluetooth: ISO: Add support for connecting multiple BISes

bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=15636364680000
start commit: 1f6ce8392d6f Add linux-next specific files for 20230613
git tree: linux-next
final oops: https://syzkaller.appspot.com/x/report.txt?x=17636364680000
console output: https://syzkaller.appspot.com/x/log.txt?x=13636364680000

kernel config: https://syzkaller.appspot.com/x/.config?x=d103d5f9125e9fe9
dashboard link: https://syzkaller.appspot.com/bug?extid=c715e1bd8dfbcb1ab176

syz repro: https://syzkaller.appspot.com/x/repro.syz?x=11287563280000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=14395963280000

Reported-by: syzbot+c715e1...@syzkaller.appspotmail.com
Fixes: 2e846cd83f62 ("Bluetooth: ISO: Add support for connecting multiple BISes")

For information about bisection process see: https://goo.gl/tpsmEJ#bisection