==================================================================
BUG: KASAN: slab-use-after-free in __hlist_del include/linux/list.h:982 [inline]
BUG: KASAN: slab-use-after-free in hlist_del_init include/linux/list.h:1008 [inline]
BUG: KASAN: slab-use-after-free in batadv_forw_packet_steal+0xfa/0x170 net/batman-adv/send.c:583
Write of size 8 at addr ffff88805687a808 by task kworker/u8:28/4832

CPU: 0 UID: 0 PID: 4832 Comm: kworker/u8:28 Not tainted 6.15.0-rc6-syzkaller-00346-g5723cc3450bc #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: bat_events batadv_iv_send_outstanding_bat_ogm_packet
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:408 [inline]
 print_report+0xb4/0x290 mm/kasan/report.c:521
 kasan_report+0x118/0x150 mm/kasan/report.c:634
 __hlist_del include/linux/list.h:982 [inline]
 hlist_del_init include/linux/list.h:1008 [inline]
 batadv_forw_packet_steal+0xfa/0x170 net/batman-adv/send.c:583
 batadv_iv_send_outstanding_bat_ogm_packet+0x6db/0x7e0 net/batman-adv/bat_iv_ogm.c:1724
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0xadb/0x17a0 kernel/workqueue.c:3319
 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400
 kthread+0x70e/0x8a0 kernel/kthread.c:464
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>

Allocated by task 29273:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:68
 poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
 __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:394
 kasan_kmalloc include/linux/kasan.h:260 [inline]
 __kmalloc_cache_noprof+0x230/0x3d0 mm/slub.c:4358
 kmalloc_noprof include/linux/slab.h:905 [inline]
 kzalloc_noprof include/linux/slab.h:1039 [inline]
 device_private_init drivers/base/core.c:3537 [inline]
 device_add+0xbe/0xb50 drivers/base/core.c:3588
 device_create_groups_vargs drivers/base/core.c:4374 [inline]
 device_create+0x25b/0x2f0 drivers/base/core.c:4413
 mac80211_hwsim_new_radio+0x418/0x5340 drivers/net/wireless/virtual/mac80211_hwsim.c:5206
 hwsim_new_radio_nl+0xea4/0x1b10 drivers/net/wireless/virtual/mac80211_hwsim.c:6243
 genl_family_rcv_msg_doit+0x212/0x300 net/netlink/genetlink.c:1115
 genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline]
 genl_rcv_msg+0x60e/0x790 net/netlink/genetlink.c:1210
 netlink_rcv_skb+0x21c/0x490 net/netlink/af_netlink.c:2534
 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219
 netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline]
 netlink_unicast+0x758/0x8d0 net/netlink/af_netlink.c:1339
 netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1883
 sock_sendmsg_nosec net/socket.c:712 [inline]
 __sock_sendmsg+0x219/0x270 net/socket.c:727
 ____sys_sendmsg+0x505/0x830 net/socket.c:2566
 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2620
 __sys_sendmsg+0x164/0x220 net/socket.c:2652
 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline]
 __do_fast_syscall_32+0xb4/0x110 arch/x86/entry/syscall_32.c:306
 do_fast_syscall_32+0x34/0x80 arch/x86/entry/syscall_32.c:331
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e

Freed by task 4823:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:68
 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:576
 poison_slab_object mm/kasan/common.c:247 [inline]
 __kasan_slab_free+0x62/0x70 mm/kasan/common.c:264
 kasan_slab_free include/linux/kasan.h:233 [inline]
 slab_free_hook mm/slub.c:2380 [inline]
 slab_free mm/slub.c:4642 [inline]
 kfree+0x193/0x440 mm/slub.c:4841
 kobject_cleanup lib/kobject.c:689 [inline]
 kobject_release lib/kobject.c:720 [inline]
 kref_put include/linux/kref.h:65 [inline]
 kobject_put+0x22b/0x480 lib/kobject.c:737
 mac80211_hwsim_del_radio+0x2c7/0x460 drivers/net/wireless/virtual/mac80211_hwsim.c:5667
 hwsim_exit_net+0x584/0x640 drivers/net/wireless/virtual/mac80211_hwsim.c:6545
 ops_exit_list net/core/net_namespace.c:172 [inline]
 cleanup_net+0x71a/0xbd0 net/core/net_namespace.c:654
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0xadb/0x17a0 kernel/workqueue.c:3319
 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400
 kthread+0x70e/0x8a0 kernel/kthread.c:464
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

The buggy address belongs to the object at ffff88805687a800
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 8 bytes inside of
 freed 512-byte region [ffff88805687a800, ffff88805687aa00)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x56878
head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801a041c80 dead000000000100 dead000000000122
raw: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000
head: 00fff00000000040 ffff88801a041c80 dead000000000100 dead000000000122
head: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000
head: 00fff00000000002 ffffea00015a1e01 00000000ffffffff 00000000ffffffff
head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000004
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 2, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 8972, tgid 8965 (syz.4.946), ts 299217536867, free_ts 280401045730
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1d8/0x230 mm/page_alloc.c:1714
 prep_new_page mm/page_alloc.c:1722 [inline]
 get_page_from_freelist+0x21ce/0x22b0 mm/page_alloc.c:3684
 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:4966
 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2301
 alloc_slab_page mm/slub.c:2450 [inline]
 allocate_slab+0x8a/0x3b0 mm/slub.c:2618
 new_slab mm/slub.c:2672 [inline]
 ___slab_alloc+0xbfc/0x1480 mm/slub.c:3858
 __slab_alloc mm/slub.c:3948 [inline]
 __slab_alloc_node mm/slub.c:4023 [inline]
 slab_alloc_node mm/slub.c:4184 [inline]
 __do_kmalloc_node mm/slub.c:4326 [inline]
 __kmalloc_noprof+0x305/0x4f0 mm/slub.c:4339
 kmalloc_noprof include/linux/slab.h:909 [inline]
 io_cache_alloc_new+0x40/0x100 io_uring/alloc_cache.c:40
 io_cache_alloc io_uring/alloc_cache.h:59 [inline]
 io_uring_alloc_async_data io_uring/io_uring.h:248 [inline]
 io_msg_alloc_async+0x1b2/0x2d0 io_uring/net.c:174
 io_recvmsg_prep_setup io_uring/net.c:728 [inline]
 io_recvmsg_prep+0x60c/0xde0 io_uring/net.c:807
 io_init_req io_uring/io_uring.c:2134 [inline]
 io_submit_sqe io_uring/io_uring.c:2181 [inline]
 io_submit_sqes+0x93d/0x1d20 io_uring/io_uring.c:2336
 __do_sys_io_uring_enter io_uring/io_uring.c:3396 [inline]
 __se_sys_io_uring_enter+0x2df/0x2b20 io_uring/io_uring.c:3330
 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline]
 __do_fast_syscall_32+0xb4/0x110 arch/x86/entry/syscall_32.c:306
 do_fast_syscall_32+0x34/0x80 arch/x86/entry/syscall_32.c:331
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e
page last free pid 5882 tgid 5882 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1258 [inline]
 __free_frozen_pages+0xb0e/0xcd0 mm/page_alloc.c:2721
 vfree+0x1a6/0x330 mm/vmalloc.c:3384
 pcpu_mem_free mm/percpu.c:523 [inline]
 pcpu_free_chunk mm/percpu.c:1489 [inline]
 pcpu_destroy_chunk mm/percpu-vm.c:368 [inline]
 pcpu_balance_free+0x6ae/0x940 mm/percpu.c:1977
 pcpu_balance_workfn+0xd01/0xe00 mm/percpu.c:2206
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0xadb/0x17a0 kernel/workqueue.c:3319
 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400
 kthread+0x70e/0x8a0 kernel/kthread.c:464
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

Memory state around the buggy address:
 ffff88805687a700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88805687a780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88805687a800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                      ^
 ffff88805687a880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88805687a900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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