possible deadlock in genl

Kernel	Title	Count	Last	Reported	Patched	Status
upstream	possible deadlock in genl_rcv net	1	2329d	2324d	0/26	closed as invalid on 2018/02/13 19:42
linux-4.19	possible deadlock in genl_rcv (2)	1	893d	893d	0/1	auto-closed as invalid on 2022/03/12 20:05
upstream	possible deadlock in genl_rcv (3) net	1	850d	846d	0/26	auto-closed as invalid on 2022/04/25 11:14
upstream	possible deadlock in genl_rcv (2) net	2	1870d	1930d	0/26	auto-closed as invalid on 2019/09/08 03:35

====================================================== WARNING: possible circular locking dependency detected 4.19.107-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor.3/22347 is trying to acquire lock: 00000000c9afe8a4 (cb_lock){++++}, at: genl_rcv+0x15/0x40 net/netlink/genetlink.c:637 but task is already holding lock: 00000000ce8784fe (&pipe->mutex/1){+.+.}, at: pipe_lock_nested fs/pipe.c:62 [inline] 00000000ce8784fe (&pipe->mutex/1){+.+.}, at: pipe_lock+0x63/0x80 fs/pipe.c:70 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #4 (&pipe->mutex/1){+.+.}: pipe_lock_nested fs/pipe.c:62 [inline] pipe_lock+0x63/0x80 fs/pipe.c:70 iter_file_splice_write+0x183/0xb30 fs/splice.c:700 do_splice_from fs/splice.c:852 [inline] do_splice+0x5ea/0x1250 fs/splice.c:1154 __do_sys_splice fs/splice.c:1428 [inline] __se_sys_splice fs/splice.c:1408 [inline] __x64_sys_splice+0x2b5/0x320 fs/splice.c:1408 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe -> #3 (sb_writers#4){.+.+}: sb_start_write include/linux/fs.h:1578 [inline] mnt_want_write+0x3a/0xb0 fs/namespace.c:360 ovl_create_object+0x96/0x290 fs/overlayfs/dir.c:600 lookup_open+0x11f6/0x19b0 fs/namei.c:3235 do_last fs/namei.c:3327 [inline] path_openat+0x13cb/0x4200 fs/namei.c:3537 do_filp_open+0x1a1/0x280 fs/namei.c:3567 do_sys_open+0x3c0/0x500 fs/open.c:1088 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe -> #2 (&ovl_i_mutex_dir_key[depth]){++++}: inode_lock_shared include/linux/fs.h:757 [inline] lookup_slow+0x43/0x70 fs/namei.c:1688 walk_component+0x70a/0x1ee0 fs/namei.c:1811 link_path_walk.part.0+0x8fd/0x1210 fs/namei.c:2142 link_path_walk fs/namei.c:2073 [inline] path_openat+0x1ed/0x4200 fs/namei.c:3536 do_filp_open+0x1a1/0x280 fs/namei.c:3567 file_open_name+0x291/0x370 fs/open.c:1035 filp_open+0x47/0x70 fs/open.c:1055 kernel_read_file_from_path+0x78/0xf0 fs/exec.c:971 fw_get_filesystem_firmware drivers/base/firmware_loader/main.c:328 [inline] _request_firmware+0x6f3/0x10f0 drivers/base/firmware_loader/main.c:587 request_firmware+0x33/0x50 drivers/base/firmware_loader/main.c:636 reg_reload_regdb+0x7a/0x240 net/wireless/reg.c:1073 genl_family_rcv_msg+0x627/0xc10 net/netlink/genetlink.c:602 genl_rcv_msg+0xbf/0x160 net/netlink/genetlink.c:627 netlink_rcv_skb+0x160/0x410 net/netlink/af_netlink.c:2454 genl_rcv+0x24/0x40 net/netlink/genetlink.c:638 netlink_unicast_kernel net/netlink/af_netlink.c:1317 [inline] netlink_unicast+0x4d7/0x6a0 net/netlink/af_netlink.c:1343 netlink_sendmsg+0x80b/0xcd0 net/netlink/af_netlink.c:1908 sock_sendmsg_nosec net/socket.c:622 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:632 ___sys_sendmsg+0x803/0x920 net/socket.c:2115 __sys_sendmsg+0xec/0x1b0 net/socket.c:2153 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe -> #1 (genl_mutex){+.+.}: genl_lock net/netlink/genetlink.c:33 [inline] genl_lock_all net/netlink/genetlink.c:54 [inline] genl_register_family net/netlink/genetlink.c:331 [inline] genl_register_family+0x1c4/0x10e3 net/netlink/genetlink.c:322 genl_init+0x12/0x62 net/netlink/genetlink.c:1047 do_one_initcall+0xf1/0x734 init/main.c:883 do_initcall_level init/main.c:951 [inline] do_initcalls init/main.c:959 [inline] do_basic_setup init/main.c:977 [inline] kernel_init_freeable+0x4c9/0x5bb init/main.c:1144 kernel_init+0xd/0x1c0 init/main.c:1061 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 -> #0 (cb_lock){++++}: down_read+0x37/0xb0 kernel/locking/rwsem.c:24 genl_rcv+0x15/0x40 net/netlink/genetlink.c:637 netlink_unicast_kernel net/netlink/af_netlink.c:1317 [inline] netlink_unicast+0x4d7/0x6a0 net/netlink/af_netlink.c:1343 netlink_sendmsg+0x80b/0xcd0 net/netlink/af_netlink.c:1908 sock_sendmsg_nosec net/socket.c:622 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:632 sock_no_sendpage+0xf8/0x140 net/core/sock.c:2642 kernel_sendpage+0x82/0xd0 net/socket.c:3378 sock_sendpage+0x84/0xa0 net/socket.c:847 pipe_to_sendpage+0x263/0x320 fs/splice.c:452 splice_from_pipe_feed fs/splice.c:503 [inline] __splice_from_pipe+0x38f/0x7a0 fs/splice.c:627 splice_from_pipe+0xd9/0x140 fs/splice.c:662 do_splice_from fs/splice.c:852 [inline] do_splice+0x5ea/0x1250 fs/splice.c:1154 __do_sys_splice fs/splice.c:1428 [inline] __se_sys_splice fs/splice.c:1408 [inline] __x64_sys_splice+0x2b5/0x320 fs/splice.c:1408 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe other info that might help us debug this: Chain exists of: cb_lock --> sb_writers#4 --> &pipe->mutex/1 Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&pipe->mutex/1); lock(sb_writers#4); lock(&pipe->mutex/1); lock(cb_lock); *** DEADLOCK *** 1 lock held by syz-executor.3/22347: #0: 00000000ce8784fe (&pipe->mutex/1){+.+.}, at: pipe_lock_nested fs/pipe.c:62 [inline] #0: 00000000ce8784fe (&pipe->mutex/1){+.+.}, at: pipe_lock+0x63/0x80 fs/pipe.c:70 stack backtrace: CPU: 0 PID: 22347 Comm: syz-executor.3 Not tainted 4.19.107-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x188/0x20d lib/dump_stack.c:118 print_circular_bug.isra.0.cold+0x1c4/0x282 kernel/locking/lockdep.c:1221 check_prev_add kernel/locking/lockdep.c:1861 [inline] check_prevs_add kernel/locking/lockdep.c:1974 [inline] validate_chain kernel/locking/lockdep.c:2415 [inline] __lock_acquire+0x2e19/0x49c0 kernel/locking/lockdep.c:3411 lock_acquire+0x170/0x400 kernel/locking/lockdep.c:3903 down_read+0x37/0xb0 kernel/locking/rwsem.c:24 genl_rcv+0x15/0x40 net/netlink/genetlink.c:637 netlink_unicast_kernel net/netlink/af_netlink.c:1317 [inline] netlink_unicast+0x4d7/0x6a0 net/netlink/af_netlink.c:1343 netlink_sendmsg+0x80b/0xcd0 net/netlink/af_netlink.c:1908 sock_sendmsg_nosec net/socket.c:622 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:632 sock_no_sendpage+0xf8/0x140 net/core/sock.c:2642 kernel_sendpage+0x82/0xd0 net/socket.c:3378 sock_sendpage+0x84/0xa0 net/socket.c:847 pipe_to_sendpage+0x263/0x320 fs/splice.c:452 splice_from_pipe_feed fs/splice.c:503 [inline] __splice_from_pipe+0x38f/0x7a0 fs/splice.c:627 splice_from_pipe+0xd9/0x140 fs/splice.c:662 do_splice_from fs/splice.c:852 [inline] do_splice+0x5ea/0x1250 fs/splice.c:1154 __do_sys_splice fs/splice.c:1428 [inline] __se_sys_splice fs/splice.c:1408 [inline] __x64_sys_splice+0x2b5/0x320 fs/splice.c:1408 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45c479 Code: ad b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 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 0f 83 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007fec83c94c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000113 RAX: ffffffffffffffda RBX: 00007fec83c956d4 RCX: 000000000045c479 RDX: 0000000000000005 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 000000000076bfc0 R08: 000000000004ffe0 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000b9f R14: 00000000004ce270 R15: 000000000076bfcc audit: type=1400 audit(1583320017.711:489): avc: denied { map } for pid=23546 comm="syz-executor.1" path="socket:[161730]" dev="sockfs" ino=161730 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=tcp_socket permissive=1 selinux_nlmsg_perm: 50 callbacks suppressed SELinux: unrecognized netlink message: protocol=0 nlmsg_type=0 sclass=netlink_route_socket pig=23687 comm=syz-executor.3 --map-set only usable from mangle table SELinux: unrecognized netlink message: protocol=0 nlmsg_type=0 sclass=netlink_route_socket pig=23687 comm=syz-executor.3 SELinux: unrecognized netlink message: protocol=0 nlmsg_type=0 sclass=netlink_route_socket pig=23687 comm=syz-executor.3 gfs2: not a GFS2 filesystem SELinux: unrecognized netlink message: protocol=0 nlmsg_type=0 sclass=netlink_route_socket pig=23687 comm=syz-executor.3 SELinux: unrecognized netlink message: protocol=0 nlmsg_type=0 sclass=netlink_route_socket pig=23687 comm=syz-executor.3 gfs2: not a GFS2 filesystem --map-set only usable from mangle table SELinux: unrecognized netlink message: protocol=0 nlmsg_type=0 sclass=netlink_route_socket pig=23687 comm=syz-executor.3 SELinux: unrecognized netlink message: protocol=0 nlmsg_type=0 sclass=netlink_route_socket pig=23687 comm=syz-executor.3 gfs2: not a GFS2 filesystem SELinux: unrecognized netlink message: protocol=0 nlmsg_type=0 sclass=netlink_route_socket pig=23687 comm=syz-executor.3 SELinux: unrecognized netlink message: protocol=0 nlmsg_type=0 sclass=netlink_route_socket pig=23687 comm=syz-executor.3 SELinux: unrecognized netlink message: protocol=0 nlmsg_type=0 sclass=netlink_route_socket pig=23687 comm=syz-executor.3 --map-set only usable from mangle table gfs2: not a GFS2 filesystem --map-set only usable from mangle table gfs2: not a GFS2 filesystem