BUG: sleeping function called from invalid context at include/linux/sched/mm.h:274
in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 8619, name: syz-executor.5
preempt_count: 201, expected: 0
RCU nest depth: 0, expected: 0
2 locks held by syz-executor.5/8619:
#0: ffffffff8e2988e8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
#0: ffffffff8e2988e8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x720/0xf00 net/core/rtnetlink.c:6104
#1: ffff8880753b2908 (&sch->q.lock){+...}-{2:2}, at: netem_change+0x17e/0x1ea0 net/sched/sch_netem.c:969
Preemption disabled at:
[<0000000000000000>] 0x0
CPU: 1 PID: 8619 Comm: syz-executor.5 Not tainted 6.1.45-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023
Call Trace:
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
__might_resched+0x5cb/0x780 kernel/sched/core.c:9941
might_alloc include/linux/sched/mm.h:274 [inline]
slab_pre_alloc_hook+0x4a/0x2a0 mm/slab.h:710
slab_alloc_node mm/slub.c:3318 [inline]
__kmem_cache_alloc_node+0x47/0x260 mm/slub.c:3437
__do_kmalloc_node mm/slab_common.c:954 [inline]
__kmalloc_node+0xa2/0x230 mm/slab_common.c:962
kmalloc_node include/linux/slab.h:579 [inline]
kvmalloc_node+0x6e/0x180 mm/util.c:581
kvmalloc include/linux/slab.h:706 [inline]
get_dist_table+0x91/0x380 net/sched/sch_netem.c:788
netem_change+0x947/0x1ea0 net/sched/sch_netem.c:985
netem_init+0x58/0xb0 net/sched/sch_netem.c:1072
qdisc_create+0x8a1/0x1220 net/sched/sch_api.c:1314
tc_modify_qdisc+0x9e0/0x1da0 net/sched/sch_api.c:1723
rtnetlink_rcv_msg+0x776/0xf00 net/core/rtnetlink.c:6107
netlink_rcv_skb+0x1cd/0x410 net/netlink/af_netlink.c:2525
netlink_unicast_kernel net/netlink/af_netlink.c:1328 [inline]
netlink_unicast+0x7bf/0x990 net/netlink/af_netlink.c:1354
netlink_sendmsg+0xa26/0xd60 net/netlink/af_netlink.c:1903
sock_sendmsg_nosec net/socket.c:716 [inline]
sock_sendmsg net/socket.c:736 [inline]
____sys_sendmsg+0x59e/0x8f0 net/socket.c:2482
___sys_sendmsg net/socket.c:2536 [inline]
__sys_sendmsg+0x2a9/0x390 net/socket.c:2565
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+0x63/0xcd
RIP: 0033:0x7f1a7807cae9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 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 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f1a78e470c8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f1a7819c050 RCX: 00007f1a7807cae9
RDX: 0000000000000000 RSI: 00000000200001c0 RDI: 0000000000000003
RBP: 00007f1a780c847a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000006e R14: 00007f1a7819c050 R15: 00007ffc1ac8ae08
============================================
WARNING: possible recursive locking detected
6.1.45-syzkaller #0 Tainted: G W
--------------------------------------------
syz-executor.5/8619 is trying to acquire lock:
ffff8880753b2908 (&sch->q.lock){+...}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:355 [inline]
ffff8880753b2908 (&sch->q.lock){+...}-{2:2}, at: get_dist_table+0x254/0x380 net/sched/sch_netem.c:798
but task is already holding lock:
ffff8880753b2908 (&sch->q.lock){+...}-{2:2}, at: netem_change+0x17e/0x1ea0 net/sched/sch_netem.c:969
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0
----
lock(&sch->q.lock);
lock(&sch->q.lock);
*** DEADLOCK ***
May be due to missing lock nesting notation
2 locks held by syz-executor.5/8619:
#0: ffffffff8e2988e8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
#0: ffffffff8e2988e8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x720/0xf00 net/core/rtnetlink.c:6104
#1: ffff8880753b2908 (&sch->q.lock){+...}-{2:2}, at: netem_change+0x17e/0x1ea0 net/sched/sch_netem.c:969
stack backtrace:
CPU: 1 PID: 8619 Comm: syz-executor.5 Tainted: G W 6.1.45-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023
Call Trace:
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
print_deadlock_bug kernel/locking/lockdep.c:2991 [inline]
check_deadlock kernel/locking/lockdep.c:3034 [inline]
validate_chain+0x4726/0x58e0 kernel/locking/lockdep.c:3819
__lock_acquire+0x125b/0x1f80 kernel/locking/lockdep.c:5056
lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5669
__raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline]
_raw_spin_lock_bh+0x31/0x40 kernel/locking/spinlock.c:178
spin_lock_bh include/linux/spinlock.h:355 [inline]
get_dist_table+0x254/0x380 net/sched/sch_netem.c:798
netem_change+0x947/0x1ea0 net/sched/sch_netem.c:985
netem_init+0x58/0xb0 net/sched/sch_netem.c:1072
qdisc_create+0x8a1/0x1220 net/sched/sch_api.c:1314
tc_modify_qdisc+0x9e0/0x1da0 net/sched/sch_api.c:1723
rtnetlink_rcv_msg+0x776/0xf00 net/core/rtnetlink.c:6107
netlink_rcv_skb+0x1cd/0x410 net/netlink/af_netlink.c:2525
netlink_unicast_kernel net/netlink/af_netlink.c:1328 [inline]
netlink_unicast+0x7bf/0x990 net/netlink/af_netlink.c:1354
netlink_sendmsg+0xa26/0xd60 net/netlink/af_netlink.c:1903
sock_sendmsg_nosec net/socket.c:716 [inline]
sock_sendmsg net/socket.c:736 [inline]
____sys_sendmsg+0x59e/0x8f0 net/socket.c:2482
___sys_sendmsg net/socket.c:2536 [inline]
__sys_sendmsg+0x2a9/0x390 net/socket.c:2565
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+0x63/0xcd
RIP: 0033:0x7f1a7807cae9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 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 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f1a78e470c8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f1a7819c050 RCX: 00007f1a7807cae9
RDX: 0000000000000000 RSI: 00000000200001c0 RDI: 0000000000000003
RBP: 00007f1a780c847a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000006e R14: 00007f1a7819c050 R15: 00007ffc1ac8ae08