[v6.1] possible deadlock in nci_start_poll

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 42616e0f09fb Linux 6.1.15
git tree: linux-6.1.y
console output: https://syzkaller.appspot.com/x/log.txt?x=1746602ac80000
kernel config: https://syzkaller.appspot.com/x/.config?x=650737f7e9682672
dashboard link: https://syzkaller.appspot.com/bug?extid=29ba00fca1f346f5a374
compiler: Debian clang version 15.0.7, GNU ld (GNU Binutils for Debian) 2.35.2
userspace arch: arm64
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=11ad6688c80000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=10938692c80000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/f10713d1fd0f/disk-42616e0f.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/5a1307bb774e/vmlinux-42616e0f.xz
kernel image: https://storage.googleapis.com/syzbot-assets/388238a30fe4/Image-42616e0f.gz.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+29ba00...@syzkaller.appspotmail.com

======================================================
WARNING: possible circular locking dependency detected
6.1.15-syzkaller #0 Not tainted
------------------------------------------------------
syz-executor303/4382 is trying to acquire lock:
ffff0000d9d49350 (&ndev->req_lock){+.+.}-{3:3}, at: nci_request net/nfc/nci/core.c:148 [inline]
ffff0000d9d49350 (&ndev->req_lock){+.+.}-{3:3}, at: nci_set_local_general_bytes net/nfc/nci/core.c:774 [inline]
ffff0000d9d49350 (&ndev->req_lock){+.+.}-{3:3}, at: nci_start_poll+0x498/0x1204 net/nfc/nci/core.c:838

but task is already holding lock:
ffff0000d9d4a520 (&genl_data->genl_data_mutex){+.+.}-{3:3}, at: nfc_genl_start_poll+0x1a8/0x308 net/nfc/netlink.c:826

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #3 (&genl_data->genl_data_mutex){+.+.}-{3:3}:
__mutex_lock_common+0x190/0x21a0 kernel/locking/mutex.c:603
__mutex_lock kernel/locking/mutex.c:747 [inline]
mutex_lock_nested+0x38/0x44 kernel/locking/mutex.c:799
nfc_urelease_event_work+0xfc/0x2a8 net/nfc/netlink.c:1835
process_one_work+0x848/0x16b4 kernel/workqueue.c:2289
worker_thread+0x8e4/0xfec kernel/workqueue.c:2436
kthread+0x24c/0x2d4 kernel/kthread.c:376
ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:860

-> #2 (nfc_devlist_mutex){+.+.}-{3:3}:
__mutex_lock_common+0x190/0x21a0 kernel/locking/mutex.c:603
__mutex_lock kernel/locking/mutex.c:747 [inline]
mutex_lock_nested+0x38/0x44 kernel/locking/mutex.c:799
nfc_register_device+0x4c/0x310 net/nfc/core.c:1116
nci_register_device+0x6ac/0x7c4 net/nfc/nci/core.c:1256
virtual_ncidev_open+0x6c/0xd8 drivers/nfc/virtual_ncidev.c:146
misc_open+0x2f0/0x368 drivers/char/misc.c:143
chrdev_open+0x3e8/0x4fc fs/char_dev.c:414
do_dentry_open+0x734/0xfa0 fs/open.c:882
vfs_open+0x7c/0x90 fs/open.c:1013
do_open fs/namei.c:3557 [inline]
path_openat+0x1e10/0x2540 fs/namei.c:3714
do_filp_open+0x1bc/0x3cc fs/namei.c:3741
do_sys_openat2+0x128/0x3d8 fs/open.c:1310
do_sys_open fs/open.c:1326 [inline]
__do_sys_openat fs/open.c:1342 [inline]
__se_sys_openat fs/open.c:1337 [inline]
__arm64_sys_openat+0x1f0/0x240 fs/open.c:1337
__invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
invoke_syscall+0x98/0x2c0 arch/arm64/kernel/syscall.c:52
el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
do_el0_svc+0x64/0x218 arch/arm64/kernel/syscall.c:206
el0_svc+0x58/0x168 arch/arm64/kernel/entry-common.c:637
el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:581

-> #1 (nci_mutex){+.+.}-{3:3}:
__mutex_lock_common+0x190/0x21a0 kernel/locking/mutex.c:603
__mutex_lock kernel/locking/mutex.c:747 [inline]
mutex_lock_nested+0x38/0x44 kernel/locking/mutex.c:799
virtual_nci_close+0x28/0x58 drivers/nfc/virtual_ncidev.c:44
nci_open_device net/nfc/nci/core.c:544 [inline]
nci_dev_up+0x754/0xb10 net/nfc/nci/core.c:631
nfc_dev_up+0x154/0x300 net/nfc/core.c:118
nfc_genl_dev_up+0x98/0xdc net/nfc/netlink.c:770
genl_family_rcv_msg_doit net/netlink/genetlink.c:756 [inline]
genl_family_rcv_msg net/netlink/genetlink.c:833 [inline]
genl_rcv_msg+0x948/0xc2c net/netlink/genetlink.c:850
netlink_rcv_skb+0x20c/0x3b8 net/netlink/af_netlink.c:2550
genl_rcv+0x38/0x50 net/netlink/genetlink.c:861
netlink_unicast_kernel net/netlink/af_netlink.c:1328 [inline]
netlink_unicast+0x660/0x8d4 net/netlink/af_netlink.c:1354
netlink_sendmsg+0x800/0xae0 net/netlink/af_netlink.c:1931
sock_sendmsg_nosec net/socket.c:714 [inline]
sock_sendmsg net/socket.c:734 [inline]
____sys_sendmsg+0x558/0x844 net/socket.c:2485
___sys_sendmsg net/socket.c:2539 [inline]
__sys_sendmsg+0x26c/0x33c net/socket.c:2568
__do_sys_sendmsg net/socket.c:2577 [inline]
__se_sys_sendmsg net/socket.c:2575 [inline]
__arm64_sys_sendmsg+0x80/0x94 net/socket.c:2575
__invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
invoke_syscall+0x98/0x2c0 arch/arm64/kernel/syscall.c:52
el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
do_el0_svc+0x64/0x218 arch/arm64/kernel/syscall.c:206
el0_svc+0x58/0x168 arch/arm64/kernel/entry-common.c:637
el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:581

-> #0 (&ndev->req_lock){+.+.}-{3:3}:
check_prev_add kernel/locking/lockdep.c:3097 [inline]
check_prevs_add kernel/locking/lockdep.c:3216 [inline]
validate_chain kernel/locking/lockdep.c:3831 [inline]
__lock_acquire+0x3338/0x764c kernel/locking/lockdep.c:5055
lock_acquire+0x2f8/0x8dc kernel/locking/lockdep.c:5668
__mutex_lock_common+0x190/0x21a0 kernel/locking/mutex.c:603
__mutex_lock kernel/locking/mutex.c:747 [inline]
mutex_lock_nested+0x38/0x44 kernel/locking/mutex.c:799
nci_request net/nfc/nci/core.c:148 [inline]
nci_set_local_general_bytes net/nfc/nci/core.c:774 [inline]
nci_start_poll+0x498/0x1204 net/nfc/nci/core.c:838
nfc_start_poll+0x164/0x2a4 net/nfc/core.c:225
nfc_genl_start_poll+0x1b8/0x308 net/nfc/netlink.c:828
genl_family_rcv_msg_doit net/netlink/genetlink.c:756 [inline]
genl_family_rcv_msg net/netlink/genetlink.c:833 [inline]
genl_rcv_msg+0x948/0xc2c net/netlink/genetlink.c:850
netlink_rcv_skb+0x20c/0x3b8 net/netlink/af_netlink.c:2550
genl_rcv+0x38/0x50 net/netlink/genetlink.c:861
netlink_unicast_kernel net/netlink/af_netlink.c:1328 [inline]
netlink_unicast+0x660/0x8d4 net/netlink/af_netlink.c:1354
netlink_sendmsg+0x800/0xae0 net/netlink/af_netlink.c:1931
sock_sendmsg_nosec net/socket.c:714 [inline]
sock_sendmsg net/socket.c:734 [inline]
____sys_sendmsg+0x558/0x844 net/socket.c:2485
___sys_sendmsg net/socket.c:2539 [inline]
__sys_sendmsg+0x26c/0x33c net/socket.c:2568
__do_sys_sendmsg net/socket.c:2577 [inline]
__se_sys_sendmsg net/socket.c:2575 [inline]
__arm64_sys_sendmsg+0x80/0x94 net/socket.c:2575
__invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
invoke_syscall+0x98/0x2c0 arch/arm64/kernel/syscall.c:52
el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
do_el0_svc+0x64/0x218 arch/arm64/kernel/syscall.c:206
el0_svc+0x58/0x168 arch/arm64/kernel/entry-common.c:637
el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:581

other info that might help us debug this:

Chain exists of:
&ndev->req_lock --> nfc_devlist_mutex --> &genl_data->genl_data_mutex

Possible unsafe locking scenario:

CPU0 CPU1
---- ----
lock(&genl_data->genl_data_mutex);
lock(nfc_devlist_mutex);
lock(&genl_data->genl_data_mutex);
lock(&ndev->req_lock);

*** DEADLOCK ***

4 locks held by syz-executor303/4382:
#0: ffff800017d78ed0 (cb_lock){++++}-{3:3}, at: genl_rcv+0x28/0x50 net/netlink/genetlink.c:860
#1: ffff800017d78d88 (genl_mutex){+.+.}-{3:3}, at: genl_lock net/netlink/genetlink.c:33 [inline]
#1: ffff800017d78d88 (genl_mutex){+.+.}-{3:3}, at: genl_rcv_msg+0x114/0xc2c net/netlink/genetlink.c:848
#2: ffff0000d9d4a520 (&genl_data->genl_data_mutex){+.+.}-{3:3}, at: nfc_genl_start_poll+0x1a8/0x308 net/nfc/netlink.c:826
#3: ffff0000d9d4a100 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:835 [inline]
#3: ffff0000d9d4a100 (&dev->mutex){....}-{3:3}, at: nfc_start_poll+0x60/0x2a4 net/nfc/core.c:208

stack backtrace:
CPU: 0 PID: 4382 Comm: syz-executor303 Not tainted 6.1.15-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/02/2023
Call trace:
dump_backtrace+0x1c8/0x1f4 arch/arm64/kernel/stacktrace.c:158
show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:165
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x108/0x170 lib/dump_stack.c:106
dump_stack+0x1c/0x58 lib/dump_stack.c:113
print_circular_bug+0x150/0x1b8 kernel/locking/lockdep.c:2055
check_noncircular+0x2cc/0x378 kernel/locking/lockdep.c:2177
check_prev_add kernel/locking/lockdep.c:3097 [inline]
check_prevs_add kernel/locking/lockdep.c:3216 [inline]
validate_chain kernel/locking/lockdep.c:3831 [inline]
__lock_acquire+0x3338/0x764c kernel/locking/lockdep.c:5055
lock_acquire+0x2f8/0x8dc kernel/locking/lockdep.c:5668
__mutex_lock_common+0x190/0x21a0 kernel/locking/mutex.c:603
__mutex_lock kernel/locking/mutex.c:747 [inline]
mutex_lock_nested+0x38/0x44 kernel/locking/mutex.c:799
nci_request net/nfc/nci/core.c:148 [inline]
nci_set_local_general_bytes net/nfc/nci/core.c:774 [inline]
nci_start_poll+0x498/0x1204 net/nfc/nci/core.c:838
nfc_start_poll+0x164/0x2a4 net/nfc/core.c:225
nfc_genl_start_poll+0x1b8/0x308 net/nfc/netlink.c:828
genl_family_rcv_msg_doit net/netlink/genetlink.c:756 [inline]
genl_family_rcv_msg net/netlink/genetlink.c:833 [inline]
genl_rcv_msg+0x948/0xc2c net/netlink/genetlink.c:850
netlink_rcv_skb+0x20c/0x3b8 net/netlink/af_netlink.c:2550
genl_rcv+0x38/0x50 net/netlink/genetlink.c:861
netlink_unicast_kernel net/netlink/af_netlink.c:1328 [inline]
netlink_unicast+0x660/0x8d4 net/netlink/af_netlink.c:1354
netlink_sendmsg+0x800/0xae0 net/netlink/af_netlink.c:1931
sock_sendmsg_nosec net/socket.c:714 [inline]
sock_sendmsg net/socket.c:734 [inline]
____sys_sendmsg+0x558/0x844 net/socket.c:2485
___sys_sendmsg net/socket.c:2539 [inline]
__sys_sendmsg+0x26c/0x33c net/socket.c:2568
__do_sys_sendmsg net/socket.c:2577 [inline]
__se_sys_sendmsg net/socket.c:2575 [inline]
__arm64_sys_sendmsg+0x80/0x94 net/socket.c:2575
__invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
invoke_syscall+0x98/0x2c0 arch/arm64/kernel/syscall.c:52
el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
do_el0_svc+0x64/0x218 arch/arm64/kernel/syscall.c:206
el0_svc+0x58/0x168 arch/arm64/kernel/entry-common.c:637
el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:581
nci: __nci_request: wait_for_completion_interruptible_timeout failed -512
nci: nci_start_poll: failed to set local general bytes
nci: __nci_request: wait_for_completion_interruptible_timeout failed 0


---
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[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: abddfcf701a5 Linux 5.15.99
git tree: linux-5.15.y
console output: https://syzkaller.appspot.com/x/log.txt?x=15443442c80000
kernel config: https://syzkaller.appspot.com/x/.config?x=e8038112e99511e7
dashboard link: https://syzkaller.appspot.com/bug?extid=5ddff90d67c87ec43952

compiler: Debian clang version 15.0.7, GNU ld (GNU Binutils for Debian) 2.35.2

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5d41fec63ff8/disk-abddfcf7.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/69db433dc01f/vmlinux-abddfcf7.xz
kernel image: https://storage.googleapis.com/syzbot-assets/a00e1270bd95/bzImage-abddfcf7.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:

Reported-by: syzbot+5ddff9...@syzkaller.appspotmail.com

======================================================
WARNING: possible circular locking dependency detected

5.15.99-syzkaller #0 Not tainted
------------------------------------------------------
syz-executor.2/18110 is trying to acquire lock:
ffff8880799a0350 (&ndev->req_lock){+.+.}-{3:3}, at: nci_request net/nfc/nci/core.c:148 [inline]
ffff8880799a0350 (&ndev->req_lock){+.+.}-{3:3}, at: nci_set_local_general_bytes net/nfc/nci/core.c:774 [inline]
ffff8880799a0350 (&ndev->req_lock){+.+.}-{3:3}, at: nci_start_poll+0x59f/0xf20 net/nfc/nci/core.c:838

but task is already holding lock:

ffff8880799a15d0 (&genl_data->genl_data_mutex){+.+.}-{3:3}, at: nfc_genl_start_poll+0x1da/0x350 net/nfc/netlink.c:826

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #3 (&genl_data->genl_data_mutex){+.+.}-{3:3}:

lock_acquire+0x1ff/0x570 kernel/locking/lockdep.c:5622
__mutex_lock_common+0x1da/0x25a0 kernel/locking/mutex.c:596
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
nfc_urelease_event_work+0x113/0x2f0 net/nfc/netlink.c:1819
process_one_work+0x90d/0x1270 kernel/workqueue.c:2306
worker_thread+0xaca/0x1280 kernel/workqueue.c:2453
kthread+0x3f6/0x4f0 kernel/kthread.c:319
ret_from_fork+0x1f/0x30 <unknown>:298

-> #2 (nfc_devlist_mutex){+.+.}-{3:3}:

lock_acquire+0x1ff/0x570 kernel/locking/lockdep.c:5622
__mutex_lock_common+0x1da/0x25a0 kernel/locking/mutex.c:596
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
nfc_register_device+0x38/0x310 net/nfc/core.c:1116
nci_register_device+0x7be/0x900 net/nfc/nci/core.c:1260
virtual_ncidev_open+0x55/0xc0 drivers/nfc/virtual_ncidev.c:146
misc_open+0x304/0x380 drivers/char/misc.c:141
chrdev_open+0x54a/0x630 fs/char_dev.c:414
do_dentry_open+0x807/0xfb0 fs/open.c:826
do_open fs/namei.c:3480 [inline]
path_openat+0x26c8/0x2ee0 fs/namei.c:3615
do_filp_open+0x21c/0x460 fs/namei.c:3642
do_sys_openat2+0x13b/0x500 fs/open.c:1211
do_sys_open fs/open.c:1227 [inline]
__do_sys_openat fs/open.c:1243 [inline]
__se_sys_openat fs/open.c:1238 [inline]
__x64_sys_openat+0x243/0x290 fs/open.c:1238
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x61/0xcb

-> #1 (nci_mutex){+.+.}-{3:3}:

lock_acquire+0x1ff/0x570 kernel/locking/lockdep.c:5622
__mutex_lock_common+0x1da/0x25a0 kernel/locking/mutex.c:596
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
virtual_nci_close+0x13/0x40 drivers/nfc/virtual_ncidev.c:44
nci_close_device+0x3a8/0x5f0 net/nfc/nci/core.c:592
nci_unregister_device+0x3c/0x230 net/nfc/nci/core.c:1295
virtual_ncidev_close+0x55/0x90 drivers/nfc/virtual_ncidev.c:166
__fput+0x3bf/0x890 fs/file_table.c:280
task_work_run+0x129/0x1a0 kernel/task_work.c:164
exit_task_work include/linux/task_work.h:32 [inline]
do_exit+0x6a3/0x2480 kernel/exit.c:872
do_group_exit+0x144/0x310 kernel/exit.c:994
get_signal+0xc66/0x14e0 kernel/signal.c:2889
arch_do_signal_or_restart+0xc3/0x1890 arch/x86/kernel/signal.c:865
handle_signal_work kernel/entry/common.c:148 [inline]
exit_to_user_mode_loop+0x97/0x130 kernel/entry/common.c:172
exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:207
__syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline]
syscall_exit_to_user_mode+0x5d/0x2b0 kernel/entry/common.c:300
do_syscall_64+0x49/0xb0 arch/x86/entry/common.c:86
entry_SYSCALL_64_after_hwframe+0x61/0xcb

-> #0 (&ndev->req_lock){+.+.}-{3:3}:

check_prev_add kernel/locking/lockdep.c:3053 [inline]
check_prevs_add kernel/locking/lockdep.c:3172 [inline]
validate_chain+0x1646/0x58b0 kernel/locking/lockdep.c:3787
__lock_acquire+0x1295/0x1ff0 kernel/locking/lockdep.c:5011
lock_acquire+0x1ff/0x570 kernel/locking/lockdep.c:5622
__mutex_lock_common+0x1da/0x25a0 kernel/locking/mutex.c:596
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743

nci_request net/nfc/nci/core.c:148 [inline]
nci_set_local_general_bytes net/nfc/nci/core.c:774 [inline]

nci_start_poll+0x59f/0xf20 net/nfc/nci/core.c:838
nfc_start_poll+0x184/0x2f0 net/nfc/core.c:225
nfc_genl_start_poll+0x1e7/0x350 net/nfc/netlink.c:828
genl_family_rcv_msg_doit net/netlink/genetlink.c:731 [inline]
genl_family_rcv_msg net/netlink/genetlink.c:775 [inline]
genl_rcv_msg+0xfbd/0x14a0 net/netlink/genetlink.c:792
netlink_rcv_skb+0x1cf/0x410 net/netlink/af_netlink.c:2533
genl_rcv+0x24/0x40 net/netlink/genetlink.c:803
netlink_unicast_kernel net/netlink/af_netlink.c:1330 [inline]
netlink_unicast+0x7b6/0x980 net/netlink/af_netlink.c:1356
netlink_sendmsg+0xa30/0xd60 net/netlink/af_netlink.c:1952
sock_sendmsg_nosec net/socket.c:704 [inline]
sock_sendmsg net/socket.c:724 [inline]
____sys_sendmsg+0x59e/0x8f0 net/socket.c:2412
___sys_sendmsg+0x252/0x2e0 net/socket.c:2466
__sys_sendmsg net/socket.c:2495 [inline]
__do_sys_sendmsg net/socket.c:2504 [inline]
__se_sys_sendmsg+0x19a/0x260 net/socket.c:2502
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x61/0xcb

other info that might help us debug this:

Chain exists of:
&ndev->req_lock --> nfc_devlist_mutex --> &genl_data->genl_data_mutex

Possible unsafe locking scenario:

CPU0 CPU1
---- ----
lock(&genl_data->genl_data_mutex);
lock(nfc_devlist_mutex);
lock(&genl_data->genl_data_mutex);
lock(&ndev->req_lock);

*** DEADLOCK ***

4 locks held by syz-executor.2/18110:
#0: ffffffff8da38c30 (cb_lock){++++}-{3:3}, at: genl_rcv+0x15/0x40 net/netlink/genetlink.c:802
#1: ffffffff8da38ae8 (genl_mutex){+.+.}-{3:3}, at: genl_lock net/netlink/genetlink.c:33 [inline]
#1: ffffffff8da38ae8 (genl_mutex){+.+.}-{3:3}, at: genl_rcv_msg+0x124/0x14a0 net/netlink/genetlink.c:790
#2: ffff8880799a15d0 (&genl_data->genl_data_mutex){+.+.}-{3:3}, at: nfc_genl_start_poll+0x1da/0x350 net/nfc/netlink.c:826
#3: ffff8880799a1190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline]
#3: ffff8880799a1190 (&dev->mutex){....}-{3:3}, at: nfc_start_poll+0x56/0x2f0 net/nfc/core.c:208

stack backtrace:
CPU: 1 PID: 18110 Comm: syz-executor.2 Not tainted 5.15.99-syzkaller #0

Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/02/2023

Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
check_noncircular+0x2f8/0x3b0 kernel/locking/lockdep.c:2133
check_prev_add kernel/locking/lockdep.c:3053 [inline]
check_prevs_add kernel/locking/lockdep.c:3172 [inline]
validate_chain+0x1646/0x58b0 kernel/locking/lockdep.c:3787
__lock_acquire+0x1295/0x1ff0 kernel/locking/lockdep.c:5011
lock_acquire+0x1ff/0x570 kernel/locking/lockdep.c:5622
__mutex_lock_common+0x1da/0x25a0 kernel/locking/mutex.c:596
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743

nci_request net/nfc/nci/core.c:148 [inline]
nci_set_local_general_bytes net/nfc/nci/core.c:774 [inline]

nci_start_poll+0x59f/0xf20 net/nfc/nci/core.c:838
nfc_start_poll+0x184/0x2f0 net/nfc/core.c:225
nfc_genl_start_poll+0x1e7/0x350 net/nfc/netlink.c:828
genl_family_rcv_msg_doit net/netlink/genetlink.c:731 [inline]
genl_family_rcv_msg net/netlink/genetlink.c:775 [inline]
genl_rcv_msg+0xfbd/0x14a0 net/netlink/genetlink.c:792
netlink_rcv_skb+0x1cf/0x410 net/netlink/af_netlink.c:2533
genl_rcv+0x24/0x40 net/netlink/genetlink.c:803
netlink_unicast_kernel net/netlink/af_netlink.c:1330 [inline]
netlink_unicast+0x7b6/0x980 net/netlink/af_netlink.c:1356
netlink_sendmsg+0xa30/0xd60 net/netlink/af_netlink.c:1952
sock_sendmsg_nosec net/socket.c:704 [inline]
sock_sendmsg net/socket.c:724 [inline]
____sys_sendmsg+0x59e/0x8f0 net/socket.c:2412
___sys_sendmsg+0x252/0x2e0 net/socket.c:2466
__sys_sendmsg net/socket.c:2495 [inline]
__do_sys_sendmsg net/socket.c:2504 [inline]
__se_sys_sendmsg+0x19a/0x260 net/socket.c:2502
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7fa65d3040f9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fa65b834168 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007fa65d424120 RCX: 00007fa65d3040f9
RDX: 0000000000000000 RSI: 0000000020000440 RDI: 0000000000000005
RBP: 00007fa65d35fae9 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fff4cde01ef R14: 00007fa65b834300 R15: 0000000000022000
</TASK>

nci: __nci_request: wait_for_completion_interruptible_timeout failed -512

[syzbot]

syzbot has found a reproducer for the following issue on:

HEAD commit: abddfcf701a5 Linux 5.15.99
git tree: linux-5.15.y

console output: https://syzkaller.appspot.com/x/log.txt?x=179e2a2ac80000

kernel config: https://syzkaller.appspot.com/x/.config?x=e8038112e99511e7
dashboard link: https://syzkaller.appspot.com/bug?extid=5ddff90d67c87ec43952
compiler: Debian clang version 15.0.7, GNU ld (GNU Binutils for Debian) 2.35.2

syz repro: https://syzkaller.appspot.com/x/repro.syz?x=121b3294c80000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=12a2f3ccc80000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5d41fec63ff8/disk-abddfcf7.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/69db433dc01f/vmlinux-abddfcf7.xz
kernel image: https://storage.googleapis.com/syzbot-assets/a00e1270bd95/bzImage-abddfcf7.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+5ddff9...@syzkaller.appspotmail.com

======================================================
WARNING: possible circular locking dependency detected
5.15.99-syzkaller #0 Not tainted
------------------------------------------------------

syz-executor149/3610 is trying to acquire lock:
ffff88801dfaa350 (&ndev->req_lock){+.+.}-{3:3}, at: nci_request net/nfc/nci/core.c:148 [inline]
ffff88801dfaa350 (&ndev->req_lock){+.+.}-{3:3}, at: nci_set_local_general_bytes net/nfc/nci/core.c:774 [inline]
ffff88801dfaa350 (&ndev->req_lock){+.+.}-{3:3}, at: nci_start_poll+0x59f/0xf20 net/nfc/nci/core.c:838

but task is already holding lock:

ffff88801dfab5d0 (&genl_data->genl_data_mutex){+.+.}-{3:3}, at: nfc_genl_start_poll+0x1da/0x350 net/nfc/netlink.c:826

nci_open_device net/nfc/nci/core.c:544 [inline]
nci_dev_up+0x954/0xd40 net/nfc/nci/core.c:631
nfc_dev_up+0x185/0x330 net/nfc/core.c:118
nfc_genl_dev_up+0x80/0xd0 net/nfc/netlink.c:770

4 locks held by syz-executor149/3610:

#0: ffffffff8da38c30 (cb_lock){++++}-{3:3}, at: genl_rcv+0x15/0x40 net/netlink/genetlink.c:802
#1: ffffffff8da38ae8 (genl_mutex){+.+.}-{3:3}, at: genl_lock net/netlink/genetlink.c:33 [inline]
#1: ffffffff8da38ae8 (genl_mutex){+.+.}-{3:3}, at: genl_rcv_msg+0x124/0x14a0 net/netlink/genetlink.c:790

#2: ffff88801dfab5d0 (&genl_data->genl_data_mutex){+.+.}-{3:3}, at: nfc_genl_start_poll+0x1da/0x350 net/nfc/netlink.c:826
#3: ffff88801dfab190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline]
#3: ffff88801dfab190 (&dev->mutex){....}-{3:3}, at: nfc_start_poll+0x56/0x2f0 net/nfc/core.c:208

stack backtrace:
CPU: 0 PID: 3610 Comm: syz-executor149 Not tainted 5.15.99-syzkaller #0

RIP: 0033:0x7ff900bda649
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 41 15 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ff900b8b318 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007ff900c62428 RCX: 00007ff900bda649
RDX: 0000000000000000 RSI: 0000000020000440 RDI: 0000000000000004
RBP: 00007ff900c62420 R08: 0000000000000003 R09: 0000000000000000
R10: 0000000000000008 R11: 0000000000000246 R12: 00007ff900c30074
R13: 00007ffd089d5a6f R14: 00007ff900b8b400 R15: 0000000000022000

</TASK>
nci: __nci_request: wait_for_completion_interruptible_timeout failed -512

nci: nci_start_poll: failed to set local general bytes

[syzbot]

syzbot suspects this issue could be fixed by backporting the following commit:

commit b2e44aac91b25abbed57d785089c4b7af926a7bd
git tree: upstream
Author: Dmitry Vyukov <dvy...@google.com>
Date: Tue Nov 15 10:00:17 2022 +0000

NFC: nci: Allow to create multiple virtual nci devices

bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=121315f0680000
kernel config: https://syzkaller.appspot.com/x/.config?x=b49b0405a60858ed
dashboard link: https://syzkaller.appspot.com/bug?extid=29ba00fca1f346f5a374
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=169d30b6c80000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=17edef75c80000


Please keep in mind that other backports might be required as well.

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

[syzbot]

syzbot suspects this issue could be fixed by backporting the following commit:

commit b2e44aac91b25abbed57d785089c4b7af926a7bd
git tree: upstream
Author: Dmitry Vyukov <dvy...@google.com>
Date: Tue Nov 15 10:00:17 2022 +0000

NFC: nci: Allow to create multiple virtual nci devices

bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=1661f149680000
kernel config: https://syzkaller.appspot.com/x/.config?x=f0ea19992afd55ad
dashboard link: https://syzkaller.appspot.com/bug?extid=5ddff90d67c87ec43952
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=126459d7c80000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=143c5f2c280000