[syzbot] [mm?] BUG: sleeping function called from invalid context in bucket_table_alloc

[syzbot] [mm?] BUG: sleeping function called from invalid context in bucket_table_alloc

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit:    7079a12d7506 Add linux-next specific files for 20260820
git tree:       linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=119afa25580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=aa9dec010c9e69a7
dashboard link: https://syzkaller.appspot.com/bug?extid=0dbf6d295b3350944f0b
compiler:       Debian clang version 22.1.8 (++20260613092233+e80beda6e255-1~exp1~20260613092250.77), Debian LLD 22.1.8

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/9682e92d9ec7/disk-7079a12d.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/829f3c29b6e1/vmlinux-7079a12d.xz
kernel image: https://storage.googleapis.com/syzbot-assets/2e0cdd08b0f5/bzImage-7079a12d.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+0dbf6d295b3350944f0b@syzkaller.appspotmail.com

BUG: sleeping function called from invalid context at ./include/linux/sched/mm.h:322
in_atomic(): 0, irqs_disabled(): 0, non_block: 0, pid: 15133, name: syz.6.1501
preempt_count: 0, expected: 0
RCU nest depth: 1, expected: 0
locks held by syz.6.1501/15133: 2, last CPU#1:
 #0: ffffffff90250500 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
 #0: ffffffff90250500 (rtnl_mutex){+.+.}-{4:4}, at: rtnetlink_rcv_msg+0x767/0xc00 net/core/rtnetlink.c:7138
 #1: ffffffff8ed5ca60 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
 #1: ffffffff8ed5ca60 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
 #1: ffffffff8ed5ca60 (rcu_read_lock){....}-{1:3}, at: rhashtable_insert_slow+0x1cf/0x2000 lib/rhashtable.c:683
CPU: 1 UID: 0 PID: 15133 Comm: syz.6.1501 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
 __might_resched+0x36a/0x4c0 kernel/sched/core.c:9236
 might_alloc include/linux/sched/mm.h:322 [inline]
 slab_pre_alloc_hook mm/slub.c:4636 [inline]
 slab_alloc_node mm/slub.c:4974 [inline]
 __do_kmalloc_node mm/slub.c:5413 [inline]
 __kmalloc_noprof+0xef/0x720 mm/slub.c:5439
 _kmalloc_noprof include/linux/slab.h:995 [inline]
 _kzalloc_noprof include/linux/slab.h:1312 [inline]
 alloc_pages_bulk_weighted_interleave mm/mempolicy.c:2682 [inline]
 alloc_pages_bulk_mempolicy_noprof+0xaef/0x1690 mm/mempolicy.c:2785
 vm_area_alloc_pages mm/vmalloc.c:3736 [inline]
 __vmalloc_area_node mm/vmalloc.c:3914 [inline]
 __vmalloc_node_range_noprof+0xa0a/0x1540 mm/vmalloc.c:4104
 __vmalloc_node_noprof mm/vmalloc.c:4165 [inline]
 __vmalloc_area_node mm/vmalloc.c:3890 [inline]
 __vmalloc_node_range_noprof+0x58b/0x1540 mm/vmalloc.c:4104
 __kvmalloc_node_noprof+0x5a1/0x820 mm/slub.c:7033
 bucket_table_alloc+0x75/0x380 lib/rhashtable.c:197
 rhashtable_insert_rehash lib/rhashtable.c:503 [inline]
 rhashtable_try_insert lib/rhashtable.c:671 [inline]
 rhashtable_insert_slow+0x1c66/0x2000 lib/rhashtable.c:684
 __rhashtable_insert_fast include/linux/rhashtable.h:789 [inline]
 rhashtable_lookup_insert_fast include/linux/rhashtable.h:966 [inline]
 vxlan_vni_add drivers/net/vxlan/vxlan_vnifilter.c:744 [inline]
 vxlan_vni_add_del drivers/net/vxlan/vxlan_vnifilter.c:824 [inline]
 vxlan_process_vni_filter drivers/net/vxlan/vxlan_vnifilter.c:891 [inline]
 vxlan_vnifilter_process+0x357a/0x4d40 drivers/net/vxlan/vxlan_vnifilter.c:973
 rtnetlink_rcv_msg+0x7b9/0xc00 net/core/rtnetlink.c:7141
 netlink_rcv_skb+0x226/0x4a0 net/netlink/af_netlink.c:2556
 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
 netlink_unicast+0x7bd/0x940 net/netlink/af_netlink.c:1345
 netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1900
 sock_sendmsg_nosec+0x13a/0x180 net/socket.c:800
 __sock_sendmsg net/socket.c:815 [inline]
 ____sys_sendmsg+0x54e/0x850 net/socket.c:2713
 ___sys_sendmsg+0x2a5/0x360 net/socket.c:2767
 __sys_sendmsg net/socket.c:2799 [inline]
 __do_sys_sendmsg net/socket.c:2804 [inline]
 __se_sys_sendmsg net/socket.c:2802 [inline]
 __x64_sys_sendmsg+0x1b1/0x290 net/socket.c:2802


---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzkaller@googlegroups.com.

syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.

If the report is already addressed, let syzbot know by replying with:
#syz fix: exact-commit-title

If you want to overwrite report's subsystems, reply with:
#syz set subsystems: new-subsystem
(See the list of subsystem names on the web dashboard)

If the report is a duplicate of another one, reply with:
#syz dup: exact-subject-of-another-report

If you want to undo deduplication, reply with:
#syz undup