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KASAN: slab-use-after-free Read in hwsim_set_promiscuous_mode

Status: upstream: reported on 2026/06/23 00:31
Subsystems: wpan
Labels: prio:high actionable
[Documentation on labels]
Reported-by: syzbot+4707bb8a43a42fca2b97@syzkaller.appspotmail.com
First crash: 5d10h, last: 5d10h
▶ ▼ ✨ AI Jobs (2)
ID Workflow Result Correct Bug Created Started Finished Revision Error
6591f055-e60b-4068-b03d-af47de57df7d moderation Actionable: ✅ ❓ KASAN: slab-use-after-free Read in hwsim_set_promiscuous_mode 2026/06/23 00:24 2026/06/23 00:24 2026/06/23 00:30 5a630be623a83f54a0e7a5a72d78827acdc85248 

			
				
	

	
	

		fcf364d1-466b-4aad-8eef-80a99f19b1f3
		assessment-security
		
			
				
					DenialOfService: ✅
				
			
				
					Exploitable: ✅
				
			
				
					FilesystemTrigger: ❌
				
			
				
					NetworkTrigger: ❌
				
			
				
					PeripheralTrigger: ❌
				
			
				
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					UserNamespace: ✅
				
			
				
					VMGuestTrigger: ❌
				
			
				
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		❓
		KASAN: slab-use-after-free Read in hwsim_set_promiscuous_mode
		2026/06/20 00:39
		2026/06/20 00:39
		2026/06/20 01:40
		023e42b533e586523329e56d8cc833583d338ca9
		
			

			
				
	

	
	



			

		

	

	
	

		

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			[syzbot] [wpan?] KASAN: slab-use-after-free Read in hwsim_set_promiscuous_mode
			0 (1)
			2026/06/23 00:31
		

	
	




			
			
		

	

	

	
	
Sample crash report:

	
netdevsim netdevsim0 netdevsim0: left allmulticast mode
8021q: adding VLAN 0 to HW filter on device netdevsim0
8021q: adding VLAN 0 to HW filter on device netdevsim1
8021q: adding VLAN 0 to HW filter on device netdevsim2
8021q: adding VLAN 0 to HW filter on device netdevsim3
==================================================================
BUG: KASAN: slab-use-after-free in hwsim_set_promiscuous_mode+0x2b4/0x2e0 drivers/net/ieee802154/mac802154_hwsim.c:323
Read of size 1 at addr ffff88802adb1800 by task syz.0.303/7013

CPU: 1 UID: 0 PID: 7013 Comm: syz.0.303 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
 print_address_description+0x55/0x1e0 mm/kasan/report.c:378
 print_report+0x58/0x70 mm/kasan/report.c:482
 kasan_report+0x117/0x150 mm/kasan/report.c:595
 hwsim_set_promiscuous_mode+0x2b4/0x2e0 drivers/net/ieee802154/mac802154_hwsim.c:323
 drv_set_promiscuous_mode+0x159/0x2e0 net/mac802154/driver-ops.h:127
 drv_start net/mac802154/driver-ops.h:195 [inline]
 mac802154_slave_open net/mac802154/iface.c:196 [inline]
 mac802154_wpan_open+0x196e/0x29f0 net/mac802154/iface.c:295
 __dev_open+0x46f/0x850 net/core/dev.c:1702
 __dev_change_flags+0x329/0x820 net/core/dev.c:9754
 netif_change_flags+0x7c/0x1b0 net/core/dev.c:9817
 do_setlink+0xdd6/0x4670 net/core/rtnetlink.c:3207
 rtnl_group_changelink net/core/rtnetlink.c:3855 [inline]
 __rtnl_newlink net/core/rtnetlink.c:4023 [inline]
 rtnl_newlink+0x148e/0x1bd0 net/core/rtnetlink.c:4151
 rtnetlink_rcv_msg+0x802/0xc00 net/core/rtnetlink.c:7068
 netlink_rcv_skb+0x226/0x4a0 net/netlink/af_netlink.c:2556
 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
 netlink_unicast+0x7bb/0x940 net/netlink/af_netlink.c:1345
 netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1900
 sock_sendmsg_nosec net/socket.c:775 [inline]
 __sock_sendmsg net/socket.c:790 [inline]
 ____sys_sendmsg+0x9b9/0xa20 net/socket.c:2684
 ___sys_sendmsg+0x2a5/0x360 net/socket.c:2738
 __sys_sendmsg net/socket.c:2770 [inline]
 __do_sys_sendmsg net/socket.c:2775 [inline]
 __se_sys_sendmsg net/socket.c:2773 [inline]
 __x64_sys_sendmsg+0x1b1/0x290 net/socket.c:2773
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff94f19ce59
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ff9500a3028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007ff94f416090 RCX: 00007ff94f19ce59
RDX: 0000000000000000 RSI: 0000200000000180 RDI: 0000000000000008
RBP: 00007ff94f232d6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ff94f416128 R14: 00007ff94f416090 R15: 00007ffcb835f4f8
 </TASK>

Allocated by task 5605:
 kasan_save_stack mm/kasan/common.c:57 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
 poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
 __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:415
 kasan_kmalloc include/linux/kasan.h:263 [inline]
 __kmalloc_cache_noprof+0x318/0x660 mm/slub.c:5451
 _kmalloc_noprof include/linux/slab.h:969 [inline]
 _kzalloc_noprof include/linux/slab.h:1286 [inline]
 hwsim_update_pib+0x88/0x450 drivers/net/ieee802154/mac802154_hwsim.c:101
 hwsim_set_promiscuous_mode+0x196/0x2e0 drivers/net/ieee802154/mac802154_hwsim.c:323
 drv_set_promiscuous_mode+0x159/0x2e0 net/mac802154/driver-ops.h:127
 drv_start net/mac802154/driver-ops.h:195 [inline]
 mac802154_slave_open net/mac802154/iface.c:196 [inline]
 mac802154_wpan_open+0x196e/0x29f0 net/mac802154/iface.c:295
 __dev_open+0x46f/0x850 net/core/dev.c:1702
 __dev_change_flags+0x329/0x820 net/core/dev.c:9754
 netif_change_flags+0x7c/0x1b0 net/core/dev.c:9817
 do_setlink+0xdd6/0x4670 net/core/rtnetlink.c:3207
 rtnl_changelink net/core/rtnetlink.c:3841 [inline]
 __rtnl_newlink net/core/rtnetlink.c:4014 [inline]
 rtnl_newlink+0x15c2/0x1bd0 net/core/rtnetlink.c:4151
 rtnetlink_rcv_msg+0x802/0xc00 net/core/rtnetlink.c:7068
 netlink_rcv_skb+0x226/0x4a0 net/netlink/af_netlink.c:2556
 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
 netlink_unicast+0x7bb/0x940 net/netlink/af_netlink.c:1345
 netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1900
 sock_sendmsg_nosec net/socket.c:775 [inline]
 __sock_sendmsg net/socket.c:790 [inline]
 __sys_sendto+0x626/0x6c0 net/socket.c:2252
 __do_sys_sendto net/socket.c:2259 [inline]
 __se_sys_sendto net/socket.c:2255 [inline]
 __x64_sys_sendto+0xde/0x100 net/socket.c:2255
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 23:
 kasan_save_stack mm/kasan/common.c:57 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:584
 poison_slab_object mm/kasan/common.c:253 [inline]
 __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285
 kasan_slab_free include/linux/kasan.h:235 [inline]
 slab_free_hook mm/slub.c:2700 [inline]
 __rcu_free_sheaf_prepare+0x12d/0x2a0 mm/slub.c:2951
 rcu_free_sheaf+0x31/0x200 mm/slub.c:5909
 rcu_do_batch kernel/rcu/tree.c:2645 [inline]
 rcu_core+0x78b/0x10a0 kernel/rcu/tree.c:2897
 handle_softirqs+0x225/0x840 kernel/softirq.c:622
 run_ksoftirqd+0x36/0x60 kernel/softirq.c:1076
 smpboot_thread_fn+0x57c/0xa80 kernel/smpboot.c:160
 kthread+0x388/0x470 kernel/kthread.c:436
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

The buggy address belongs to the object at ffff88802adb1800
 which belongs to the cache kmalloc-64 of size 64
The buggy address is located 0 bytes inside of
 freed 64-byte region [ffff88802adb1800, ffff88802adb1840)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2adb1
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000000 ffff88813fe1b8c0 dead000000000100 dead000000000122
raw: 0000000000000000 0000000800200020 00000000f5000000 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Unmovable, gfp_mask 0xd2cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 12, tgid 12 (kworker/u8:0), ts 8480159325, free_ts 7414718607
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x22d/0x280 mm/page_alloc.c:1853
 prep_new_page mm/page_alloc.c:1861 [inline]
 get_page_from_freelist+0x24ae/0x2530 mm/page_alloc.c:3941
 __alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5221
 alloc_slab_page mm/slub.c:3289 [inline]
 allocate_slab+0x74/0x5d0 mm/slub.c:3404
 new_slab mm/slub.c:3447 [inline]
 refill_objects+0x328/0x3c0 mm/slub.c:7241
 refill_sheaf mm/slub.c:2827 [inline]
 __pcs_replace_empty_main+0x2e0/0x6b0 mm/slub.c:4692
 alloc_from_pcs mm/slub.c:4790 [inline]
 slab_alloc_node mm/slub.c:4924 [inline]
 __do_kmalloc_node mm/slub.c:5333 [inline]
 __kmalloc_noprof+0x464/0x750 mm/slub.c:5347
 _kmalloc_noprof include/linux/slab.h:973 [inline]
 _kzalloc_noprof include/linux/slab.h:1286 [inline]
 lsm_blob_alloc security/security.c:218 [inline]
 lsm_task_alloc security/security.c:270 [inline]
 security_task_alloc+0x4d/0x330 security/security.c:2785
 copy_process+0x1c57/0x42e0 kernel/fork.c:2269
 kernel_clone+0x2d7/0x940 kernel/fork.c:2745
 user_mode_thread+0x110/0x180 kernel/fork.c:2821
 call_usermodehelper_exec_work+0x5c/0x230 kernel/umh.c:171
 process_one_work kernel/workqueue.c:3314 [inline]
 process_scheduled_works+0xa8e/0x14e0 kernel/workqueue.c:3397
 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3478
 kthread+0x388/0x470 kernel/kthread.c:436
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
page last free pid 10 tgid 10 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 __free_pages_prepare mm/page_alloc.c:1397 [inline]
 __free_frozen_pages+0xc0d/0xd20 mm/page_alloc.c:2938
 vfree+0x1fd/0x330 mm/vmalloc.c:3472
 delayed_vfree_work+0x55/0x80 mm/vmalloc.c:3392
 process_one_work kernel/workqueue.c:3314 [inline]
 process_scheduled_works+0xa8e/0x14e0 kernel/workqueue.c:3397
 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3478
 kthread+0x388/0x470 kernel/kthread.c:436
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

Memory state around the buggy address:
 ffff88802adb1700: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
 ffff88802adb1780: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
>ffff88802adb1800: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
                   ^
 ffff88802adb1880: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
 ffff88802adb1900: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
==================================================================



	

	



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			2026/06/18 06:07
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			KASAN: slab-use-after-free Read in hwsim_set_promiscuous_mode
		

		
		


* Struck through repros no longer work on HEAD.